Depositional environments

@techreport{bornhauser1948possible9,
    author = "Bornhauser, M",
    title = "Possible ancient submarine canyon in southwestern Louisiana",
    year = "1948",
    howpublished = "American Association of Petroleum Geologists Bulletin, v. 32, p. 2287-2290",
    note = "talkorigins\_source = {true}; raw\_reference = {Bornhauser, M., 1948, Possible ancient submarine canyon in southwestern Louisiana: American Association of Petroleum Geologists Bulletin, v. 32, p. 2287-2290.}"
}

@article{kuenen1950turbidity27,
    author = "Kuenen, P. H. and Migliorini, C",
    title = "Turbidity currents as a cause of graded bedding",
    year = "1950",
    journal = "Journal of Geology, v. 58, p. 91-127",
    note = "talkorigins\_source = {true}; raw\_reference = {Kuenen, P. H., and Migliorini, C., 1950, Turbidity currents as a cause of graded bedding: Journal of Geology, v. 58, p. 91-127.}"
}

ABSTRACT The type and distribution of much of the minor topography in the northeastern Pacific basin can be correlated with the accessibility of a given area to deposition from turbidity currents. Deep-sea areas separated from North America by basins or troughs, which act as sediment traps for turbidity currents, are characterized by a highly irregular relief of a few hundred feet. Other areas connected to the continent by a gradual continuous slope are characterized by very smooth plains like those of the North Atlantic sea floor. These plains slope out from the continent except in the vicinity of long ridges on the sea floor. The plains slope around the ridges because the slopes are formed by turbidity currents and the ridges act as dams to deflect the currents to one side. Roug-bottomed basins thousands of feet deep are found in the regions of smooth plains, but with one exception all are inaccessible to turbidity currents because they are surrounded by mountains, or lie on the “lee” side of ridges relative to the general direction of flow of turbidity currents. The exceptional basin is in a seismically active area, and it may have formed too recently to be filled by turbidity-current deposition. Turbidity currents have formed deep-sea fans at the mouths of many submarine canyons, and deep-sea channels cross most, if not all, of the fans. All twelve of the channels which have been explored in any detail hook sharply to the left across the fans. This left hook can be explained as a secondary effect of the action of Coriolis force on the turbidity currents which formed the channels. Without channels, this type of flow would have no tendency to hook left. Unchannelized turbidity currents are required to form the fans.

@article{doi1013065ceae13616bb11d78645000102c1865d,
    author = "Menard, H. W.",
    title = "Deep-Sea Channels, Topography, and Sedimentation",
    year = "1955",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT The type and distribution of much of the minor topography in the northeastern Pacific basin can be correlated with the accessibility of a given area to deposition from turbidity currents. Deep-sea areas separated from North America by basins or troughs, which act as sediment traps for turbidity currents, are characterized by a highly irregular relief of a few hundred feet. Other areas connected to the continent by a gradual continuous slope are characterized by very smooth plains like those of the North Atlantic sea floor. These plains slope out from the continent except in the vicinity of long ridges on the sea floor. The plains slope around the ridges because the slopes are formed by turbidity currents and the ridges act as dams to deflect the currents to one side. Roug-bottomed basins thousands of feet deep are found in the regions of smooth plains, but with one exception all are inaccessible to turbidity currents because they are surrounded by mountains, or lie on the “lee” side of ridges relative to the general direction of flow of turbidity currents. The exceptional basin is in a seismically active area, and it may have formed too recently to be filled by turbidity-current deposition. Turbidity currents have formed deep-sea fans at the mouths of many submarine canyons, and deep-sea channels cross most, if not all, of the fans. All twelve of the channels which have been explored in any detail hook sharply to the left across the fans. This left hook can be explained as a secondary effect of the action of Coriolis force on the turbidity currents which formed the channels. Without channels, this type of flow would have no tendency to hook left. Unchannelized turbidity currents are required to form the fans.",
    url = "https://doi.org/10.1306/5ceae136-16bb-11d7-8645000102c1865d",
    doi = "10.1306/5ceae136-16bb-11d7-8645000102c1865d",
    openalex = "W2076541925",
    references = "doi101086625710, doi101086625932, doi10113000167606195162961dsasc20co2, doi10113000167606195364865eotnam20co2, doi101130001676061955661149dotnpb20co2, doi1013063d93441516b111d78645000102c1865d, doi1013065ceadd7616bb11d78645000102c1865d, doi102110pec51020076, doi1023071438154, doi102307210015"
}

@techreport{bornhauser1960depositional10,
    author = "Bornhauser, M",
    title = "Depositional and structural history of Northwest Hartburg Field, Newton County, Texas",
    year = "1960",
    howpublished = "American Association of Petroleum Geologists Bulletin, v. 44, p. 458-470",
    note = "talkorigins\_source = {true}; raw\_reference = {Bornhauser, M., 1960, Depositional and structural history of Northwest Hartburg Field, Newton County, Texas: American Association of Petroleum Geologists Bulletin, v. 44, p. 458-470.}"
}

@misc{sullwold1961turbidites56,
    author = "Sullwold, H. H. and Jr",
    title = "Turbidites in Oil Exploration, in Peterson, J. A., and Osmond, J. C., eds., Geometry of Sand Bodies",
    year = "1961",
    howpublished = "American Association of Petroleum Geologists, p. 63-81",
    note = "talkorigins\_source = {true}; raw\_reference = {Sullwold, H. H., Jr., 1961, Turbidites in Oil Exploration, in Peterson, J. A., and Osmond, J. C., eds., Geometry of Sand Bodies: American Association of Petroleum Geologists, p. 63-81.}"
}

@book{bouma1962sedimentology11,
    author = "Bouma, A. H",
    title = "Sedimentology of some flysch deposits",
    year = "1962",
    publisher = "Amsterdam, Elsevier, 168 p",
    note = "talkorigins\_source = {true}; raw\_reference = {Bouma, A. H., 1962, Sedimentology of some flysch deposits: Amsterdam, Elsevier, 168 p.}"
}

@article{walker1967turebidite58,
    author = "Walker, R. G",
    title = "Turebidite sedimentary structures and their relationship to proximal and distal depositional environments",
    year = "1967",
    journal = "Journal of Sedimentary Petrology, v. 37, p. 25-43",
    note = "talkorigins\_source = {true}; raw\_reference = {Walker, R. G., 1967, Turebidite sedimentary structures and their relationship to proximal and distal depositional environments: Journal of Sedimentary Petrology, v. 37, p. 25-43.}"
}

@techreport{paine1968stratigraphy50,
    author = "Paine, R",
    title = "Stratigraphy and sedimentation of subsurface Hackberry wedge and associated beds of southwestern Louisiana",
    year = "1968",
    howpublished = "American Association of Petroleum Geologists Bulletin, v. 52, p. 322-342",
    note = "talkorigins\_source = {true}; raw\_reference = {Paine, R., 1968, Stratigraphy and sedimentation of subsurface Hackberry wedge and associated beds of southwestern Louisiana: American Association of Petroleum Geologists Bulletin, v. 52, p. 322-342.}"
}

@techreport{bandy1969middle1,
    author = "Bandy, O. L. and Arnal, R. E",
    title = "Middle Tertiary Basin development, San Joaquin Valley, California",
    year = "1969",
    howpublished = "Geological Society of America Bulletin, v. 80, p. 783-820",
    note = "talkorigins\_source = {true}; raw\_reference = {Bandy, O. L., and Arnal, R. E., 1969, Middle Tertiary Basin development, San Joaquin Valley, California: Geological Society of America Bulletin, v. 80, p. 783-820.}"
}

Abstract The depositional environments of La Jolla canyon, fan-valley, and fan are well known from closely spaced sounding lines, deep-diving vehicle observations, numerous undisturbed box cores, and continuous reflection profiles. The narrow rock-walled canyon changes seaward at 300 fm (549 m) to a wider valley cut into the compacted clayey sediments of a fan, and bordered by discontinuous leveelike embankments. The fan-valley merges gradually into the relatively flat floor of San Diego trough. Numerous dives into the fan-valley have shown precipitous walls along the outside of the bends of the winding channel. Slumping is taking place actively from these walls and large slump blocks of clay are common on the floor. Small scour depressions around isolated erratics suggest the erosive effect of relatively weak currents in some places but, for the most part, the muddy floor seems to have been little disturbed in recent years. Diagonal tension cracks cut the floor locally. Box cores show that most of the sediment deposited on the valley floor in the past few thousand years consists of poorly sorted clayey silt, underlain by discontinuous layers of well-sorted fine-grained sand with a few coarse sand grains, gravel, and mud balls. Sand layers occur in 94 percent of the valley axis cores, of which 26 percent are graded; 59 percent have parallel laminations; and 41 percent have current-ripple cross-laminations. Sand layers are less common in the cores from levees and from the small discontinuous terraces along the sides of the fan-valley. Cores from the open fan have less and finer grained sand. In all these environments the sand shows no consistent or systematic grain-size variation with increasing water depths. Some of the coarsest sediments, including gravel and mud balls, are found in sand farthest from shore and at the greatest depths. The character of the sand and the finding of shallow-water Foraminifera indicate the probability that sand has been carried from the coastal area along the valley axes and spilled over the levees onto the open fan. However, there is little evidence of recent high-velocity, high-density turbidity currents, because, in general, the covering mud layer is distinctly separated from the underlying sand deposits, and therefore does not suggest deposition at the terminus of a turbidity current. Also, the discontinuous character of the sands and series of laminae with heavy mineral concentrations indicate introduction by a traction type of pulsating current, such as has been seen during vehicle dives, and also has been measured in the few available current-meter records. The locally precipitous fan-valley walls and outcrops of gravel, and the sand layers on the levees and open fan, may be the product of stronger currents that moved down the valley during earlier more pluvial periods, when greater quantities of sediment entered the canyon heads. Possible confirmation of this idea comes from the available C-14 dates in plant layers, which suggest that deposition in the past few thousand years may have been considerably slower than that indicated for the Pleistocene. The finer sediments may be largely the result of slow downslope movement of slightly higher density muddy waters coming from the coastal areas. Continuous reflection profiles have shown that the inner La Jolla fan has only a thin cover of unconsolidated sediments overlying the folded and faulted Miocene-Pliocene rocks. The outer fan and adjacent San Diego trough contain a thick section (more than 1,000 m) of Quaternary sediments with probable buried older channels and possible thick lenses of sand sediments.

@article{doi1013065d25c61516c111d78645000102c1865d,
    author = "Shepard, R. F. Dill F. P. and Dill, R. F. and Rad, Ulrich Von",
    title = "Physiography and Sedimentary Processes of La Jolla Submarine Fan and Fan-Valley, California",
    year = "1969",
    journal = "AAPG Bulletin",
    abstract = "Abstract The depositional environments of La Jolla canyon, fan-valley, and fan are well known from closely spaced sounding lines, deep-diving vehicle observations, numerous undisturbed box cores, and continuous reflection profiles. The narrow rock-walled canyon changes seaward at 300 fm (549 m) to a wider valley cut into the compacted clayey sediments of a fan, and bordered by discontinuous leveelike embankments. The fan-valley merges gradually into the relatively flat floor of San Diego trough. Numerous dives into the fan-valley have shown precipitous walls along the outside of the bends of the winding channel. Slumping is taking place actively from these walls and large slump blocks of clay are common on the floor. Small scour depressions around isolated erratics suggest the erosive effect of relatively weak currents in some places but, for the most part, the muddy floor seems to have been little disturbed in recent years. Diagonal tension cracks cut the floor locally. Box cores show that most of the sediment deposited on the valley floor in the past few thousand years consists of poorly sorted clayey silt, underlain by discontinuous layers of well-sorted fine-grained sand with a few coarse sand grains, gravel, and mud balls. Sand layers occur in 94 percent of the valley axis cores, of which 26 percent are graded; 59 percent have parallel laminations; and 41 percent have current-ripple cross-laminations. Sand layers are less common in the cores from levees and from the small discontinuous terraces along the sides of the fan-valley. Cores from the open fan have less and finer grained sand. In all these environments the sand shows no consistent or systematic grain-size variation with increasing water depths. Some of the coarsest sediments, including gravel and mud balls, are found in sand farthest from shore and at the greatest depths. The character of the sand and the finding of shallow-water Foraminifera indicate the probability that sand has been carried from the coastal area along the valley axes and spilled over the levees onto the open fan. However, there is little evidence of recent high-velocity, high-density turbidity currents, because, in general, the covering mud layer is distinctly separated from the underlying sand deposits, and therefore does not suggest deposition at the terminus of a turbidity current. Also, the discontinuous character of the sands and series of laminae with heavy mineral concentrations indicate introduction by a traction type of pulsating current, such as has been seen during vehicle dives, and also has been measured in the few available current-meter records. The locally precipitous fan-valley walls and outcrops of gravel, and the sand layers on the levees and open fan, may be the product of stronger currents that moved down the valley during earlier more pluvial periods, when greater quantities of sediment entered the canyon heads. Possible confirmation of this idea comes from the available C-14 dates in plant layers, which suggest that deposition in the past few thousand years may have been considerably slower than that indicated for the Pleistocene. The finer sediments may be largely the result of slow downslope movement of slightly higher density muddy waters coming from the coastal areas. Continuous reflection profiles have shown that the inner La Jolla fan has only a thin cover of unconsolidated sediments overlying the folded and faulted Miocene-Pliocene rocks. The outer fan and adjacent San Diego trough contain a thick section (more than 1,000 m) of Quaternary sediments with probable buried older channels and possible thick lenses of sand sediments.",
    url = "https://doi.org/10.1306/5d25c615-16c1-11d7-8645000102c1865d",
    doi = "10.1306/5d25c615-16c1-11d7-8645000102c1865d",
    openalex = "W2172061626",
    references = "doi1010160025322764900453, doi1010160025322768900157, doi101086627187, doi101111j136530911965tb01550x, doi10113000167606195970279tdispa20co2, doi1013065d25b6a516c111d78645000102c1865d, doi102110pec51020076, openalexw3120543430, openalexw579005446, openalexw580680426"
}

ABSTRACT The growth pattern of a deep-sea fan relates events in and around the fan-valleys to the structure and morphology of the open fan. The growth pattern cannot be determined without knowledge of the origin and recent history of the fan-valley system. The mapping of La Jolla and San Lucas deep-sea fans with the deep-towed instrument package developed at Marine Physical Laboratory of the Scripps Institution of Oceanography details the fine-scale morphology, structure, and internal fill of the fan-valleys and suggests the growth patterns of these fans. The La Jolla fan, 20 km west of Scripps Institution, has one meandering fan-valley that extends across the entire fan. Except on the toe of the fan, the deeply incised valley has terraced walls with steeper walls on the outside of meanders. Very low-relief levees border the fan-valley in some localities. The present erosional valley bypasses the partly buried remnants of an older distributary system on the lower fan. The San Lucas fan, off the southern tip of the peninsula of Baja California, shows a depositional lobe of sediment, or suprafan, below the short, leveed fan-valley extending from San Jose Canyon. The suprafan appears as a convex-upward bulge on a radial profile of the fan. The surface of the suprafan has a series of discontinuous depressions up to 55 m deep and 1 km wide. The depressions are generally asymmetric in cross section, commonly have terraced walls, and are underlain by coarse sand and gravel. They are interpreted to be channel remnants. A model for deep-sea fan growth, based on this study, predicts that deposition on a fan will be localized in a suprafan at the end of large, leveed valleys commonly found on, and generally confined to, the upper reaches of deep-sea fans. The suprafan normally is on the midfan and is characterized by numerous smaller distributary channels. Rapid aggradation in the suprafan coupled with migration and meandering of the channels produces a surface marked by isolated depressions or channel remnants. Uniform deposition, producing a symmetrical half-cone morphology, results from the shifting through time of fan-valleys across the area of the fan.

@article{doi1013065d25cc7916c111d78645000102c1865d,
    author = "Normark, William R.",
    title = "Growth Patterns of Deep-Sea Fans",
    year = "1970",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT The growth pattern of a deep-sea fan relates events in and around the fan-valleys to the structure and morphology of the open fan. The growth pattern cannot be determined without knowledge of the origin and recent history of the fan-valley system. The mapping of La Jolla and San Lucas deep-sea fans with the deep-towed instrument package developed at Marine Physical Laboratory of the Scripps Institution of Oceanography details the fine-scale morphology, structure, and internal fill of the fan-valleys and suggests the growth patterns of these fans. The La Jolla fan, 20 km west of Scripps Institution, has one meandering fan-valley that extends across the entire fan. Except on the toe of the fan, the deeply incised valley has terraced walls with steeper walls on the outside of meanders. Very low-relief levees border the fan-valley in some localities. The present erosional valley bypasses the partly buried remnants of an older distributary system on the lower fan. The San Lucas fan, off the southern tip of the peninsula of Baja California, shows a depositional lobe of sediment, or suprafan, below the short, leveed fan-valley extending from San Jose Canyon. The suprafan appears as a convex-upward bulge on a radial profile of the fan. The surface of the suprafan has a series of discontinuous depressions up to 55 m deep and 1 km wide. The depressions are generally asymmetric in cross section, commonly have terraced walls, and are underlain by coarse sand and gravel. They are interpreted to be channel remnants. A model for deep-sea fan growth, based on this study, predicts that deposition on a fan will be localized in a suprafan at the end of large, leveed valleys commonly found on, and generally confined to, the upper reaches of deep-sea fans. The suprafan normally is on the midfan and is characterized by numerous smaller distributary channels. Rapid aggradation in the suprafan coupled with migration and meandering of the channels produces a surface marked by isolated depressions or channel remnants. Uniform deposition, producing a symmetrical half-cone morphology, results from the shifting through time of fan-valleys across the area of the fan.",
    url = "https://doi.org/10.1306/5d25cc79-16c1-11d7-8645000102c1865d",
    doi = "10.1306/5d25cc79-16c1-11d7-8645000102c1865d",
    openalex = "W1979345769",
    references = "doi101086621596, doi101086623509, doi101086625999, doi101086627271, doi101126science1523721502, doi101130001676061969801859dfpap20co2, doi1013065ceae13616bb11d78645000102c1865d, doi1013065d25c61516c111d78645000102c1865d, doi101306bc743d7f16be11d78645000102c1865d, openalexw580680426"
}

@techreport{normark1970growth47,
    author = "Normark, W. R",
    title = "Growth patterns of deep sea fans",
    year = "1970",
    howpublished = "American Association of Petroleum Geologists Bulletin, v. 54, p. 2170-2195",
    note = "talkorigins\_source = {true}; raw\_reference = {Normark, W. R., 1970, Growth patterns of deep sea fans: American Association of Petroleum Geologists Bulletin, v. 54, p. 2170-2195.}"
}

@article{benson1971geology4,
    author = "Benson, P. H",
    title = "Geology of the Oligocene Hackberry trend, Gillis English Bayou - Manchester area, Calcasieu Parish, Louisiana",
    year = "1971",
    journal = "Gulf Coast Association of Geological Societies Transactions, v. 21, p. 1-14",
    note = "talkorigins\_source = {true}; raw\_reference = {Benson, P. H., 1971, Geology of the Oligocene Hackberry trend, Gillis English Bayou - Manchester area, Calcasieu Parish, Louisiana: Gulf Coast Association of Geological Societies Transactions, v. 21, p. 1-14.}"
}

@techreport{walker1971nondeltaic59,
    author = "Walker, R. G",
    title = "Nondeltaic depositional environments in the Catskill clastic wedge (Upper Devonian) of central Pennsylvania",
    year = "1971",
    howpublished = "Geological Society of America Bulletin, v. 82, p. 1305-1326",
    note = "talkorigins\_source = {true}; raw\_reference = {Walker, R. G., 1971, Nondeltaic depositional environments in the Catskill clastic wedge (Upper Devonian) of central Pennsylvania: Geological Society of America Bulletin, v. 82, p. 1305-1326.}"
}

@misc{bazeley1972san2,
    author = "Bazeley, W",
    title = "San Emidio Nose Field",
    year = "1972",
    howpublished = "American Association of Petroleum Geologists, v. 16, p. 297-312",
    note = "talkorigins\_source = {true}; raw\_reference = {Bazeley, W., 1972, San Emidio Nose Field: American Association of Petroleum Geologists, v. 16, p. 297-312.}"
}

@techreport{davies1972deep17,
    author = "Davies, D. K",
    title = "Deep sea sediments and their sedimentation, Gulf of Mexico",
    year = "1972",
    howpublished = "American Association of Petroleum Geologists Bulletin, v. 56, p. 2212-2239",
    note = "talkorigins\_source = {true}; raw\_reference = {Davies, D. K., 1972, Deep sea sediments and their sedimentation, Gulf of Mexico: American Association of Petroleum Geologists Bulletin, v. 56, p. 2212-2239.}"
}

Navy Fan is a deep-sea fan forming as a result of the overflow of sediment from San Diego Trough into San Clemente Basin. It appears to have preserved its growth pattern unmodified by the effects of the Holocene transgression or of tectonic activity. Since the beginning of the last glaciation about 56 $$km^{3}$$ of sediment has been deposited on the fan. The fan is fed by Navy Channel, a deep gorge which cuts through the basement volcanic rock of a threshold 1,500 m deep which separates San Clemente Basin from San Diego Trough. Although it is situated 50 km offshore, Navy Channel contains gravels. The upper fan is crossed by a leveed depositional fan-valley which opens out onto the suprafan: an area of rapid sedimentation characterized by many shallow, shifting channels. Seaward of the suprafan, the lower fan passes into two small ponded basins within San Clemente Basin. The sediments of the fan comprise turbidite sands and muds and hemipelagic muds. Near-surface distribution of the sediments, determined from more than 100 cores, shows that the thickness, abundance, and grain size of turbidite sands decrease distally on the fan and that fine-grained sediments become proportionally more important. The depth of acoustic penetration with high-frequency (3.5 kHz) reflection profiling is low over the fan-valley and suprafan and increases distally. These and other spatial variations generally support concepts of proximality developed for ancient turbidites. The hemipelagic muds have a sand fraction of radiolaria and foraminifera; the sand fraction of the turbidite muds is mainly mica. The turbidite muds are siltier than the hemipelagic muds and are found in graded beds up to 30-cm thick.

@article{doi101086627725,
    author = "Normark, William R. and Piper, David J. W.",
    title = "Sediments and Growth Pattern of Navy Deep-Sea Fan, San Clemente Basin, California Borderland",
    year = "1972",
    journal = "The Journal of Geology",
    abstract = "Navy Fan is a deep-sea fan forming as a result of the overflow of sediment from San Diego Trough into San Clemente Basin. It appears to have preserved its growth pattern unmodified by the effects of the Holocene transgression or of tectonic activity. Since the beginning of the last glaciation about 56 $$km^{3}$$ of sediment has been deposited on the fan. The fan is fed by Navy Channel, a deep gorge which cuts through the basement volcanic rock of a threshold 1,500 m deep which separates San Clemente Basin from San Diego Trough. Although it is situated 50 km offshore, Navy Channel contains gravels. The upper fan is crossed by a leveed depositional fan-valley which opens out onto the suprafan: an area of rapid sedimentation characterized by many shallow, shifting channels. Seaward of the suprafan, the lower fan passes into two small ponded basins within San Clemente Basin. The sediments of the fan comprise turbidite sands and muds and hemipelagic muds. Near-surface distribution of the sediments, determined from more than 100 cores, shows that the thickness, abundance, and grain size of turbidite sands decrease distally on the fan and that fine-grained sediments become proportionally more important. The depth of acoustic penetration with high-frequency (3.5 kHz) reflection profiling is low over the fan-valley and suprafan and increases distally. These and other spatial variations generally support concepts of proximality developed for ancient turbidites. The hemipelagic muds have a sand fraction of radiolaria and foraminifera; the sand fraction of the turbidite muds is mainly mica. The turbidite muds are siltier than the hemipelagic muds and are found in graded beds up to 30-cm thick.",
    url = "https://doi.org/10.1086/627725",
    doi = "10.1086/627725",
    openalex = "W1975723602",
    references = "doi10113000167606195970279tdispa20co2, doi101130001676061969801163psotmr20co2, doi101130spe107, doi1013065d25c61516c111d78645000102c1865d, doi1013065d25cc7916c111d78645000102c1865d, doi10130674d716452b2111d78648000102c1865d, doi1015159781400876525046, doi102110pec51020014, doi102110pec65080192, openalexw3120543430"
}

ABSTRACT The southwesterly prevailing wind of the Gulf of Guinea strikes symmetrically on the nose of the Niger delta, causing divergent longshore drifts which meet opposing drifts near Lagos and Fernando Poo. Submarine canyons channel about 1 million cu m of sand a year from each pair of opposing drifts to feed submarine fans on either side of the delta foot. In times of low sea level axial distributaries of the Niger feed a third, now inactive, submarine fan in front of the delta. At the time of the last low sea level numerous submarine canyons formed on the front of the Niger delta, and their heads cut back into the Benin Formation continental sands. As the sea rose, these canyon heads formed wide estuaries which have since been filled. All Quaternary canyons except three currently scoured by resedimented longshore drift material have been filled. Because the Niger delta has prograded toward the southwest throughout the Tertiary and because the prevailing wind has blown persistently from the southwest, the longshore drift pattern long has been as it is now, and the two corners of the delta have been areas of high concentrations of submarine canyon formation. There may have been a third area of high concentration of submarine canyons between the Cross River and Niger deltas when these were separate. Recognition of the submarine fan environment leads to a new symmetrical five-layer interpretation of the structure of the Niger delta: (5) top continental sand unit (Benin Formation); (4) transitional sand/shale unit (Agbada Formation); (3) marine shale unit (Akata Formation); (2) transitional shale-sand unit (newly distinguished); (1) bottom submarine fan sand unit (newly distinguished). Other deltas feeding into waters of oceanic depths may have a comparable structure.

@article{doi101306819a41a216c511d78645000102c1865d,
    author = "Burke, Kevin",
    title = "Longshore Drift, Submarine Canyons, and Submarine Fans in Development of Niger Delta",
    year = "1972",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT The southwesterly prevailing wind of the Gulf of Guinea strikes symmetrically on the nose of the Niger delta, causing divergent longshore drifts which meet opposing drifts near Lagos and Fernando Poo. Submarine canyons channel about 1 million cu m of sand a year from each pair of opposing drifts to feed submarine fans on either side of the delta foot. In times of low sea level axial distributaries of the Niger feed a third, now inactive, submarine fan in front of the delta. At the time of the last low sea level numerous submarine canyons formed on the front of the Niger delta, and their heads cut back into the Benin Formation continental sands. As the sea rose, these canyon heads formed wide estuaries which have since been filled. All Quaternary canyons except three currently scoured by resedimented longshore drift material have been filled. Because the Niger delta has prograded toward the southwest throughout the Tertiary and because the prevailing wind has blown persistently from the southwest, the longshore drift pattern long has been as it is now, and the two corners of the delta have been areas of high concentrations of submarine canyon formation. There may have been a third area of high concentration of submarine canyons between the Cross River and Niger deltas when these were separate. Recognition of the submarine fan environment leads to a new symmetrical five-layer interpretation of the structure of the Niger delta: (5) top continental sand unit (Benin Formation); (4) transitional sand/shale unit (Agbada Formation); (3) marine shale unit (Akata Formation); (2) transitional shale-sand unit (newly distinguished); (1) bottom submarine fan sand unit (newly distinguished). Other deltas feeding into waters of oceanic depths may have a comparable structure.",
    url = "https://doi.org/10.1306/819a41a2-16c5-11d7-8645000102c1865d",
    doi = "10.1306/819a41a2-16c5-11d7-8645000102c1865d",
    openalex = "W2013494769"
}

@book{fisher1972clastic19,
    author = "Fisher, W. L. and Brown, L. F. and Jr",
    title = "Clastic depositional systems - a genetic approach to facies analysis",
    year = "1972",
    publisher = "Bureau of Economic Geology: University of Texas at Austin, p. 161-183",
    note = "talkorigins\_source = {true}; raw\_reference = {Fisher, W. L., and Brown, L. F., Jr., 1972, Clastic depositional systems - a genetic approach to facies analysis: Bureau of Economic Geology: University of Texas at Austin, p. 161-183.}"
}

@misc{mutti1972le40,
    author = "Mutti, E. and Ricci Lucchi, F",
    title = "Le torbiditi dell'Appennino settentrionale",
    year = "1972",
    howpublished = "introduzione all'ananisi di facies: Memoirs Soc. Geol. Italiana, v. 11, p. 161-199",
    note = "talkorigins\_source = {true}; raw\_reference = {Mutti, E., and Ricci Lucchi, F., 1972, Le torbiditi dell'Appennino settentrionale: introduzione all'ananisi di facies: Memoirs Soc. Geol. Italiana, v. 11, p. 161-199.}"
}

@misc{mutti1972un39,
    author = "Mutti, E. and Ghibaudo, G",
    title = "Un esempio di torbiditi di conoide sottomarina estern",
    year = "1972",
    howpublished = "le Arenarie di San Salvatore (Formazione di Bobbio, Miocene) nell'Appennino de Piacenza. Memorie dell'Accademia delle Scienze di Torino, Classe di Scienze Fisiche, Mathematiche e Naturali, Series 4, No.16, 40 p",
    note = "talkorigins\_source = {true}; raw\_reference = {Mutti, E., and Ghibaudo, G., 1972, Un esempio di torbiditi di conoide sottomarina estern: le Arenarie di San Salvatore (Formazione di Bobbio, Miocene) nell'Appennino de Piacenza. Memorie dell'Accademia delle Scienze di Torino, Classe di Scienze Fisiche, Mathematiche e Naturali, Series 4, No.16, 40 p.}"
}

@article{berg1973deepwater5,
    author = "Berg, R. R. and Findley, R",
    title = "Deep-water interpretation of Upper Wilcox sandstones from core study, Katy Field, Texas",
    year = "1973",
    journal = "Gulf Coast Association of Geological Societies Transactions, v. 23, p. 259-265",
    note = "talkorigins\_source = {true}; raw\_reference = {Berg, R. R., and Findley, R., 1973, Deep-water interpretation of Upper Wilcox sandstones from core study, Katy Field, Texas: Gulf Coast Association of Geological Societies Transactions, v. 23, p. 259-265.}"
}

@article{bouma1973leveedchannel12,
    author = "Bouma, A. H",
    title = "Leveed-channel deposits, turbidites and contourites in the deeper parts of the Gulf of Mexico",
    year = "1973",
    journal = "Gulf Coast Association of Geological Societies Transactions, p. 368-376",
    note = "talkorigins\_source = {true}; raw\_reference = {Bouma, A. H., 1973, Leveed-channel deposits, turbidites and contourites in the deeper parts of the Gulf of Mexico: Gulf Coast Association of Geological Societies Transactions, p. 368-376.}"
}

@article{crossref1973turbidites,
    title = "Turbidites and Deep-Water Sedimentation",
    year = "1973",
    journal = "Earth-Science Reviews",
    url = "https://doi.org/10.1016/0012-8252(73)90033-0",
    doi = "10.1016/0012-8252(73)90033-0",
    number = "4",
    pages = "389",
    volume = "9"
}

@misc{nelsom1973submarine43,
    author = "Nelsom, C. H. and Kulm, L. D",
    title = "Submarine fans and deep-sea channels, in Middleton, G. V., and Bouma, A. H., eds., Turbidites and deep-water sedimentation",
    year = "1973",
    howpublished = "Society of Economic Paleontologists and Mineralogists, p. 39-78",
    note = "talkorigins\_source = {true}; raw\_reference = {Nelsom, C. H., and Kulm, L. D., 1973, Submarine fans and deep-sea channels, in Middleton, G. V., and Bouma, A. H., eds., Turbidites and deep-water sedimentation: Society of Economic Paleontologists and Mineralogists, p. 39-78.}"
}

@book{walker1973moppingup60,
    author = "Walker, R. G",
    title = "Mopping-up the turbidite mess, in Ginsburg, R. N., ed., Evolving Concepts in Sedimentology",
    year = "1973",
    publisher = "Baltimore, John Hopkins Press, p. 1-37",
    note = "talkorigins\_source = {true}; raw\_reference = {Walker, R. G., 1973, Mopping-up the turbidite mess, in Ginsburg, R. N., ed., Evolving Concepts in Sedimentology: Baltimore, John Hopkins Press, p. 1-37.}"
}

@misc{walker1973turbidite63,
    author = "Walker, R. G. and Mutti, E",
    title = "Turbidite Facies and Facies Associations, in Turbidites and Deep-Water Sedimentation",
    year = "1973",
    howpublished = "SEPM, p. 119-157",
    note = "talkorigins\_source = {true}; raw\_reference = {Walker, R. G., and Mutti, E., 1973, Turbidite Facies and Facies Associations, in Turbidites and Deep-Water Sedimentation: SEPM, p. 119-157.}"
}

@misc{nelson1974depositional44,
    author = "Nelson, C. H. and Nilsen, T. H",
    title = "Depositional trends of modern and ancient deep-sea fans, in Modern and Ancient Geosynclinal Sedimentation",
    year = "1974",
    howpublished = "SEPM Special Publication 19, p. 69-91",
    note = "talkorigins\_source = {true}; raw\_reference = {Nelson, C. H., and Nilsen, T. H., 1974, Depositional trends of modern and ancient deep-sea fans, in Modern and Ancient Geosynclinal Sedimentation: SEPM Special Publication 19, p. 69-91.}"
}

@book{whitaker1974ancient64,
    author = "Whitaker, J. H. McD",
    title = "Ancient submarine canyons and fan valleys, in Modern and Ancient Geosynclinal Sedimentation, 19 of SEPM Special Publications",
    year = "1974",
    publisher = "Society of Economic Paleontologists and Mineralogists, p. 106-125",
    note = "talkorigins\_source = {true}; raw\_reference = {Whitaker, J. H. McD., 1974, Ancient submarine canyons and fan valleys, in Modern and Ancient Geosynclinal Sedimentation, 19 of SEPM Special Publications: Society of Economic Paleontologists and Mineralogists, p. 106-125.}"
}

@misc{biddle1975channel8,
    author = "Biddle, K. T. and Maher, J. C. and Carter, P. D",
    title = "Channel Turbidite Sandstones in the Elk Hills Member of the Monterey Shale, in Maher, J. C., ed., Petroleum Geology of the Naval Peeetroleum Reserve No.1, Elk Hills, Kern County, California, 912 of USGS Professional Paper",
    year = "1975",
    howpublished = "United States Geological Survey, p. 79-85",
    note = "talkorigins\_source = {true}; raw\_reference = {Biddle, K. T., Maher, J. C., and Carter, P. D., 1975, Channel Turbidite Sandstones in the Elk Hills Member of the Monterey Shale, in Maher, J. C., ed., Petroleum Geology of the Naval Peeetroleum Reserve No.1, Elk Hills, Kern County, California, 912 of USGS Professional Paper: United States Geological Survey, p. 79-85.}"
}

The focus of these notes is on the use of primary sedimentary structures and stratification sequence as tools for interpretation of depositional environment of clastic sediments, emphasizing advances in understanding that the authors judge to be important. To accomplish the primary objective, several topics have been selected. Experimental flume studies are summarized with emphasis on work which extends the understanding of distribution of bed forms over increased ranges of grain size, flow depths, or velocity. Studies of modern and ancient sedimentary sequences are used to illustrate and interpret environments of deposition. Fluvial sediments are reviewed to show how experimentally derived generalizations are applied or qualified to interpret natural environments.

@book{doi102110scn7502,
    author = "Harms, J. C. and Southard, John B. and Spearing, Darwin and Walker, Roger G.",
    title = "Depositional Environments as Interpreted from Primary Sedimentary and Stratigraphic Sequences",
    year = "1975",
    booktitle = "SEPM (Society for Sedimentary Geology) eBooks",
    abstract = "The focus of these notes is on the use of primary sedimentary structures and stratification sequence as tools for interpretation of depositional environment of clastic sediments, emphasizing advances in understanding that the authors judge to be important. To accomplish the primary objective, several topics have been selected. Experimental flume studies are summarized with emphasis on work which extends the understanding of distribution of bed forms over increased ranges of grain size, flow depths, or velocity. Studies of modern and ancient sedimentary sequences are used to illustrate and interpret environments of deposition. Fluvial sediments are reviewed to show how experimentally derived generalizations are applied or qualified to interpret natural environments.",
    url = "https://doi.org/10.2110/scn.75.02",
    doi = "10.2110/scn.75.02",
    openalex = "W1527847239"
}

@techreport{bennetts1976characteristics3,
    author = "Bennetts, K. R. W. and Pilkey, O. H",
    title = "Characteristics of three turbidites, Hispaniola-Caicos Basin",
    year = "1976",
    howpublished = "Geological Society of America Bulletin, no. 87, p. 1291-1300",
    note = "talkorigins\_source = {true}; raw\_reference = {Bennetts, K. R. W., and Pilkey, O. H., 1976, Characteristics of three turbidites, Hispaniola-Caicos Basin: Geological Society of America Bulletin, no. 87, p. 1291-1300.}"
}

@article{berg1976densityflow6,
    author = "Berg, R. R. and Powell, R. R",
    title = "Density-flow origin for Frio reservoir sandstones, Nine Mile Point Field, Aransas County, Texas",
    year = "1976",
    journal = "Gulf Coast Association of Geological Societies Transactions, v. 26, p. 310-319",
    note = "talkorigins\_source = {true}; raw\_reference = {Berg, R. R., and Powell, R. R., 1976, Density-flow origin for Frio reservoir sandstones, Nine Mile Point Field, Aransas County, Texas: Gulf Coast Association of Geological Societies Transactions, v. 26, p. 310-319.}"
}

@article{chnelson1976thinbedded,
    author = "C. H. Nelson, W. R. Normark, A. H.",
    title = "Thin-Bedded Turbidites in Modern Submarine Canyons and Fans: ABSTRACT",
    year = "1976",
    journal = "AAPG Bulletin",
    url = "https://doi.org/10.1306/83d927f8-16c7-11d7-8645000102c1865d",
    doi = "10.1306/83d927f8-16c7-11d7-8645000102c1865d",
    volume = "60"
}

@misc{embley1976new18,
    author = "Embley, R. W",
    title = "New evidence for occurrence of debris flow deposits in the deep sea",
    year = "1976",
    howpublished = "Geology, v. 4, p. 371-374",
    note = "talkorigins\_source = {true}; raw\_reference = {Embley, R. W., 1976, New evidence for occurrence of debris flow deposits in the deep sea: Geology, v. 4, p. 371-374.}"
}

@article{stuart1976form55,
    author = "Stuart, C. J. and Caughey, C. A",
    title = "Form and composition of the Mississippi fan",
    year = "1976",
    journal = "Gulf Coast Association of Geological Societies Transactions, v. 26, p. 333-343",
    note = "talkorigins\_source = {true}; raw\_reference = {Stuart, C. J., and Caughey, C. A., 1976, Form and composition of the Mississippi fan: Gulf Coast Association of Geological Societies Transactions, v. 26, p. 333-343.}"
}

@misc{walker1976facies61,
    author = "Walker, R. G",
    title = "Facies Models 2. Turbidites and associated coarse clastic deposits",
    year = "1976",
    howpublished = "Geoscience Canada, v. 3, p. 25-36",
    note = "talkorigins\_source = {true}; raw\_reference = {Walker, R. G., 1976, Facies Models 2. Turbidites and associated coarse clastic deposits: Geoscience Canada, v. 3, p. 25-36.}"
}

@article{berg1977characteristics7,
    author = "Berg, R. R. and Tedford, F. J",
    title = "Characteristics of Wilcox gas reservoirs, Northeast Thompsonville Field, Jim Hogg and Webb Counties, Texas",
    year = "1977",
    journal = "Gulf Coast Association of Geological Societies Transactions, v. 27, p. 6-19",
    note = "talkorigins\_source = {true}; raw\_reference = {Berg, R. R., and Tedford, F. J., 1977, Characteristics of Wilcox gas reservoirs, Northeast Thompsonville Field, Jim Hogg and Webb Counties, Texas: Gulf Coast Association of Geological Societies Transactions, v. 27, p. 6-19.}"
}

@article{carlson1977submarine,
    author = "Carlson, Paul R.",
    title = "Submarine canyons and deep-sea fans",
    year = "1977",
    journal = "Earth-Science Reviews",
    url = "https://doi.org/10.1016/0012-8252(77)90101-5",
    doi = "10.1016/0012-8252(77)90101-5",
    number = "1",
    pages = "104-105",
    volume = "13"
}

ABSTRACT The vertical and lateral stratigraphic relations of facies and facies associations, palaeocurrent directions, and geometry and internal organization of associated thick‐bedded and coarse‐grained bodies of sandstone provide the framework for distinguishing five thin‐bedded turbidite facies in the Eocene Hecho Group, south‐central Pyrenees, Spain. Each facies is characterized by a number of primary features which are palaeoenvironmental indicators by themselves. These features and their palaeoenvironmental significance are summarized below. The impressive regularity and lateral persistence of bedding and depositional structures, combined with the association of thin hemipelagic intercalations are typical characteristics of the basin plain thin‐bedded turbidites. Lateral variations in bed thickness, internal structures, grain size, sand: shale ratio, and amounts of hemipelagic intercalations are present in these sediments, but take place so gradually that they cannot generally be recognized at the scale of even very large exposures. The basin plain facies has a remarkable character of uniformity over great distances and considerable stratigraphic thicknesses. Thickening‐upward and/or symmetric cycles with individual thicknesses ranging from a few metres to a few tens of metres are typical of lobe‐fringe thin‐bedded turbidites. The sediments that comprise the cycles contain small but recognizable variations in bed thickness and sand: shale ratio. The diagnostic cyclic pattern can be detected in relatively small exposures. It should be noted that in absence of coarse‐grained and thick‐bedded sandstone of the depositional lobes the above cyclic pattern is diagnostic of fan‐fringe areas. An extremely irregular bedding pattern with lensing, wedding, and amalgamation of individual beds over very short distances, sharp rippled tops of many beds, and internal depositional structures indicative of mainly tractional processes without substantial fallout, are typical and exclusive characteristics of channelmouth thin‐bedded turbidites. Bundles of interbedded thin‐bedded sandstone and mudstone as thick as a few metres that are separated in vertical sequences by mudstone units of roughly similar or greater thickness are typical of interchannel thin‐bedded turbidites. The most diagnostic feature of this depositional environment is the presence of beds of sandstone filling broad shallow channels as probable crevasse‐splays. Thin, thoroughly rippled sandstone beds with marked divergence of the bedding attitude characterize the channel‐margin facies. The divergence or expansion in thickness, is consistently toward the channel axis. Small and shallow channels filled with thin‐bedded deposits, interpreted here as crevasses cut into channel edges or levees during period of severe overbanking are also characteristic.

@article{doi101111j136530911977tb00122x,
    author = "Mutti, Emiliano",
    title = "Distinctive thin‐bedded turbidite facies and related depositional environments in the Eocene Hecho Group (South‐central Pyrenees, Spain)",
    year = "1977",
    journal = "Sedimentology",
    abstract = "ABSTRACT The vertical and lateral stratigraphic relations of facies and facies associations, palaeocurrent directions, and geometry and internal organization of associated thick‐bedded and coarse‐grained bodies of sandstone provide the framework for distinguishing five thin‐bedded turbidite facies in the Eocene Hecho Group, south‐central Pyrenees, Spain. Each facies is characterized by a number of primary features which are palaeoenvironmental indicators by themselves. These features and their palaeoenvironmental significance are summarized below. The impressive regularity and lateral persistence of bedding and depositional structures, combined with the association of thin hemipelagic intercalations are typical characteristics of the basin plain thin‐bedded turbidites. Lateral variations in bed thickness, internal structures, grain size, sand: shale ratio, and amounts of hemipelagic intercalations are present in these sediments, but take place so gradually that they cannot generally be recognized at the scale of even very large exposures. The basin plain facies has a remarkable character of uniformity over great distances and considerable stratigraphic thicknesses. Thickening‐upward and/or symmetric cycles with individual thicknesses ranging from a few metres to a few tens of metres are typical of lobe‐fringe thin‐bedded turbidites. The sediments that comprise the cycles contain small but recognizable variations in bed thickness and sand: shale ratio. The diagnostic cyclic pattern can be detected in relatively small exposures. It should be noted that in absence of coarse‐grained and thick‐bedded sandstone of the depositional lobes the above cyclic pattern is diagnostic of fan‐fringe areas. An extremely irregular bedding pattern with lensing, wedding, and amalgamation of individual beds over very short distances, sharp rippled tops of many beds, and internal depositional structures indicative of mainly tractional processes without substantial fallout, are typical and exclusive characteristics of channelmouth thin‐bedded turbidites. Bundles of interbedded thin‐bedded sandstone and mudstone as thick as a few metres that are separated in vertical sequences by mudstone units of roughly similar or greater thickness are typical of interchannel thin‐bedded turbidites. The most diagnostic feature of this depositional environment is the presence of beds of sandstone filling broad shallow channels as probable crevasse‐splays. Thin, thoroughly rippled sandstone beds with marked divergence of the bedding attitude characterize the channel‐margin facies. The divergence or expansion in thickness, is consistently toward the channel axis. Small and shallow channels filled with thin‐bedded deposits, interpreted here as crevasses cut into channel edges or levees during period of severe overbanking are also characteristic.",
    url = "https://doi.org/10.1111/j.1365-3091.1977.tb00122.x",
    doi = "10.1111/j.1365-3091.1977.tb00122.x",
    openalex = "W2162397024",
    references = "doi1010079783642962912, doi1010160025322770900447, doi1010160025322772900734, doi101111j136530911975tb01638x, doi101111j136530911976tb00038x, doi101306212f6cb72b2411d78648000102c1865d, doi1013065d25b6a516c111d78645000102c1865d, doi1013065d25cc7916c111d78645000102c1865d, doi10130674d716452b2111d78648000102c1865d, doi102110pec65080034"
}

@book{parker1977deepsea51,
    author = "Parker, J. R",
    title = "Deep-sea sands, in Developments in Petroleum Geology",
    year = "1977",
    publisher = "Essex, England, Applied Science Publications, Limited, v. 1, p. 225-242",
    note = "talkorigins\_source = {true}; raw\_reference = {Parker, J. R., 1977, Deep-sea sands, in Developments in Petroleum Geology: Essex, England, Applied Science Publications, Limited, v. 1, p. 225-242.}"
}

@book{parker1977lower52,
    author = "Parker, J. R",
    title = "Lower Tertiary sand development in the central North Sea, in Developments in Petroleum Geology",
    year = "1977",
    publisher = "Essex, England, Applied Science Publications, Limited, v. 1, p. 447-453",
    note = "talkorigins\_source = {true}; raw\_reference = {Parker, J. R., 1977, Lower Tertiary sand development in the central North Sea, in Developments in Petroleum Geology: Essex, England, Applied Science Publications, Limited, v. 1, p. 447-453.}"
}

@misc{bouma1978intraslope13,
    author = "Bouma, A. H. and Smith, L. B. and Sidner, B. R. and McKee, T. R",
    title = "Intraslope basin in Northwest Gulf of Mexico, in, 7 of AAPG Studies in Geology",
    year = "1978",
    howpublished = "American Association of Petroleum Geologists, p. 289-302",
    note = "talkorigins\_source = {true}; raw\_reference = {Bouma, A. H., Smith, L. B., Sidner, B. R., and McKee, T. R., 1978, Intraslope basin in Northwest Gulf of Mexico, in, 7 of AAPG Studies in Geology: American Association of Petroleum Geologists, p. 289-302.}"
}

Abstract Five main facies of deep-water clastic rocks can be defined: classic turbidites, massive sandstones, pebbly sandstones, conglomerates, and debris flows (with slumps and slides). The classic turbidites consist of monotonously parallel-interbedded sandstones and shales without channeling; internal sedimentary structures include grading, parallel lamination, and cross-lamination. Massive sandstones are thicker, coarser, and commonly channelized. They lack the sedimentary structures of classic turbidites, but do contain evidence of dewatering during deposition. Pebbly sandstones tend to be well graded, and can contain parallel stratification and large-scale cross-stratification. Conglomerates are characterized by inverse and normal grading, parallel and cross-stratification, and commonly have a preferred clast fabric (imbrication). Both the pebbly sandstones and conglomerates commonly are channelized. The facies can be fitted into a model of submarine-fan deposition. Modern fans are subdivided into an upper fan (suprafan), characterized by (1) a single deep channel with levees, (2) a middle fan, built up from suprafan lobes that periodically switch in position, and (3) a topographically smooth lower fan. The suprafan lobes have shallow, braided channels on their inner parts, but the outer suprafan lobes are smooth, and grade basinward into the smooth lower fan and basin plain. The smooth suprafan lobes and lower fan are characterized by deposition of the classic turbidite facies, and the braided part of the suprafan lobes by massive and pebbly sandstones. When one lobe is abandoned and another starts to prograde elsewhere, the first lobe is blanketed by mud, forming a potential stratigraphic trap. The upper-fan channel is an area of coarse sediment deposition, or conglomerates where gravel and boulders are supplied to the basin. During fan progradation, thickening- and coarsening-upward facies sequences can be formed in a manner analogous to those of deltas. Fan channels also can be abandoned progressively, forming thinning- and fining-upward sequences similar to those of fluvial or distributary channels. These sequences can be identified on electric logs. Where basin shales act as hydrocarbon-source areas, the classic turbidites can act as conduits, leading the hydrocarbons to the thicker, laterally coalesced massive and pebbly sandstones of the braided suprafan lobes. These bodies can be of the order of 25 km in diameter, and up to 100 m thick. The coarse deposits of the upper-fan channel also might form good reservoirs, being bounded by shales (levee deposits) on either side, and possibly by shales above if the fan-channel system is abandoned. Such channels can be tens of kilometers long, several kilometers wide, and a few hundred meters deep. Reservoirs may be present in all of these environments.

@article{doi101306c1ea4f7716c911d78645000102c1865d,
    author = "Walker, Roger G.",
    title = "Deep-Water Sandstone Facies and Ancient Submarine Fans: Models for Exploration for Stratigraphic Traps",
    year = "1978",
    journal = "AAPG Bulletin",
    abstract = "Abstract Five main facies of deep-water clastic rocks can be defined: classic turbidites, massive sandstones, pebbly sandstones, conglomerates, and debris flows (with slumps and slides). The classic turbidites consist of monotonously parallel-interbedded sandstones and shales without channeling; internal sedimentary structures include grading, parallel lamination, and cross-lamination. Massive sandstones are thicker, coarser, and commonly channelized. They lack the sedimentary structures of classic turbidites, but do contain evidence of dewatering during deposition. Pebbly sandstones tend to be well graded, and can contain parallel stratification and large-scale cross-stratification. Conglomerates are characterized by inverse and normal grading, parallel and cross-stratification, and commonly have a preferred clast fabric (imbrication). Both the pebbly sandstones and conglomerates commonly are channelized. The facies can be fitted into a model of submarine-fan deposition. Modern fans are subdivided into an upper fan (suprafan), characterized by (1) a single deep channel with levees, (2) a middle fan, built up from suprafan lobes that periodically switch in position, and (3) a topographically smooth lower fan. The suprafan lobes have shallow, braided channels on their inner parts, but the outer suprafan lobes are smooth, and grade basinward into the smooth lower fan and basin plain. The smooth suprafan lobes and lower fan are characterized by deposition of the classic turbidite facies, and the braided part of the suprafan lobes by massive and pebbly sandstones. When one lobe is abandoned and another starts to prograde elsewhere, the first lobe is blanketed by mud, forming a potential stratigraphic trap. The upper-fan channel is an area of coarse sediment deposition, or conglomerates where gravel and boulders are supplied to the basin. During fan progradation, thickening- and coarsening-upward facies sequences can be formed in a manner analogous to those of deltas. Fan channels also can be abandoned progressively, forming thinning- and fining-upward sequences similar to those of fluvial or distributary channels. These sequences can be identified on electric logs. Where basin shales act as hydrocarbon-source areas, the classic turbidites can act as conduits, leading the hydrocarbons to the thicker, laterally coalesced massive and pebbly sandstones of the braided suprafan lobes. These bodies can be of the order of 25 km in diameter, and up to 100 m thick. The coarse deposits of the upper-fan channel also might form good reservoirs, being bounded by shales (levee deposits) on either side, and possibly by shales above if the fan-channel system is abandoned. Such channels can be tens of kilometers long, several kilometers wide, and a few hundred meters deep. Reservoirs may be present in all of these environments.",
    url = "https://doi.org/10.1306/c1ea4f77-16c9-11d7-8645000102c1865d",
    doi = "10.1306/c1ea4f77-16c9-11d7-8645000102c1865d",
    openalex = "W4253862311",
    references = "doi101086625710, doi101111j136530911975tb00290x, doi101111j136530911976tb00051x, doi101111j136530911977tb00122x, doi10113000167606195970279tdispa20co2, doi101130001676061969801859dfpap20co2, doi10113000167606197586737gfmfrc20co2, doi101144pygs3511, doi101306212f6cb72b2411d78648000102c1865d, doi1013065d25c61516c111d78645000102c1865d, doi1013065d25cc7916c111d78645000102c1865d, doi10130674d716452b2111d78648000102c1865d"
}

@article{lund1978preplatform36,
    author = "Lund, J. W. and King, J. S. and Berlitz, R. and Gilreath, J. A",
    title = "Pre-platform exploration of High Island, Blocks A-560 and A-561",
    year = "1978",
    journal = "Gulf Coast Association of Geological Societies Transactions, v. 28, p. 273-294",
    note = "talkorigins\_source = {true}; raw\_reference = {Lund, J. W., King, J. S., Berlitz, R., and Gilreath, J. A., 1978, Pre-platform exploration of High Island, Blocks A-560 and A-561: Gulf Coast Association of Geological Societies Transactions, v. 28, p. 273-294.}"
}

@article{nilsen1978turbidites45,
    author = "Nilsen, T. H",
    title = "Turbidites of the Northern Appennines",
    year = "1978",
    journal = "Introduction to facies analysis: International Geology Review, v. 20, p. 125-166",
    note = "talkorigins\_source = {true}; raw\_reference = {Nilsen, T. H., 1978, Turbidites of the Northern Appennines: Introduction to facies analysis: International Geology Review, v. 20, p. 125-166.}"
}

The growth-pattern concept for modern submarine fans has been reviewed and broadened by additional data published or obtained in the last five years. The similarities in morphology, structure, and surficial-sedimentation patterns among modern fans from different geographic and geologic settings support a general growth-pattern model that can be applied to ancient turbidite deposits. Most submarine fans have three recognizable morphologic divisions that are related to distinct facies associations for sandy and coarser turbidites. (1) The large-leveed valley(s) of the upper fan produce wide (1 to 5 km) valley-floor deposits that are the coarsest on the fan and are deposited in meandering or braided, shallow channels within the general confines of the valley. These coarse deposits grade laterally into finer grained and more regularly bedded levee sands and silts. (2) The middle-fan region is recognized as a convex-upward depositional bulge on a radial profile and includes a depositional lobe or suprafan at the terminus of the leveed valley. The coarsening- and thickening-upward sequence of sandy turbidites on the upper suprafan are cut by numerous channels, channel remnants, and isolated depressions, whereas the lower suprafan is relatively free of such features. Suprafan channels are generally less than 1 km across and probably are filled by thinning-and fining-upward sequences. (3) The lower fan division is characteristically free of channel features (and coarse turbidites), is nearly flat-wing or ponded, and, therefore, is indistinguishable morphologically from basin-plain or abyssal-plain settings in many cases. Basin shape and relief and the ultimate size of the fan appear less important than sediment-input parameters, such as the grain-size distribution and rate of sediment supply, in controlling development of the three morphologic divisions of the fan. Specifically, canyon-fed systems common along western North America tend to have a single-leveed valley terminating in a suprafan depositional lobe; some fans, such as the Monterey, have slightly more complex features where more than one canyon is involved in fan development. If the grain-size distribution is weighted toward the silt and clay fractions as in some delta-fed systems, the fans tend to have multiple-leveed valleys on the upper fan (although only one may be active at any given time), to have long valleys crossing much of the fan, and to lack (or have poorly developed) suprafan relief.

@article{normark1978fan,
    author = "Normark, William R.",
    title = "Fan Valleys, Channels, and Depositional Lobes on Modern Submarine Fans: Characters for Recognition of Sandy Turbidite Environments",
    year = "1978",
    journal = "AAPG Bulletin",
    abstract = "The growth-pattern concept for modern submarine fans has been reviewed and broadened by additional data published or obtained in the last five years. The similarities in morphology, structure, and surficial-sedimentation patterns among modern fans from different geographic and geologic settings support a general growth-pattern model that can be applied to ancient turbidite deposits. Most submarine fans have three recognizable morphologic divisions that are related to distinct facies associations for sandy and coarser turbidites. (1) The large-leveed valley(s) of the upper fan produce wide (1 to 5 km) valley-floor deposits that are the coarsest on the fan and are deposited in meandering or braided, shallow channels within the general confines of the valley. These coarse deposits grade laterally into finer grained and more regularly bedded levee sands and silts. (2) The middle-fan region is recognized as a convex-upward depositional bulge on a radial profile and includes a depositional lobe or suprafan at the terminus of the leveed valley. The coarsening- and thickening-upward sequence of sandy turbidites on the upper suprafan are cut by numerous channels, channel remnants, and isolated depressions, whereas the lower suprafan is relatively free of such features. Suprafan channels are generally less than 1 km across and probably are filled by thinning-and fining-upward sequences. (3) The lower fan division is characteristically free of channel features (and coarse turbidites), is nearly flat-wing or ponded, and, therefore, is indistinguishable morphologically from basin-plain or abyssal-plain settings in many cases. Basin shape and relief and the ultimate size of the fan appear less important than sediment-input parameters, such as the grain-size distribution and rate of sediment supply, in controlling development of the three morphologic divisions of the fan. Specifically, canyon-fed systems common along western North America tend to have a single-leveed valley terminating in a suprafan depositional lobe; some fans, such as the Monterey, have slightly more complex features where more than one canyon is involved in fan development. If the grain-size distribution is weighted toward the silt and clay fractions as in some delta-fed systems, the fans tend to have multiple-leveed valleys on the upper fan (although only one may be active at any given time), to have long valleys crossing much of the fan, and to lack (or have poorly developed) suprafan relief.",
    url = "https://doi.org/10.1306/c1ea4f72-16c9-11d7-8645000102c1865d",
    doi = "10.1306/c1ea4f72-16c9-11d7-8645000102c1865d",
    number = "6",
    openalex = "W1989132023",
    pages = "912-931",
    volume = "62",
    references = "doi1010160025322776900839, doi101029jc074i018p04544, doi101086627725, doi101111j136530911977tb00122x, doi101130001676061969801859dfpap20co2, doi10113000167606197182563gotbdf20co2, doi1013065ceae13616bb11d78645000102c1865d, doi1013065d25c61516c111d78645000102c1865d, doi1013065d25cc7916c111d78645000102c1865d, openalexw580680426"
}

@techreport{normark1978fan48,
    author = "Normark, W. R",
    title = "Fan valleys, channels, and depositional lobes on modern submarine fans",
    year = "1978",
    howpublished = "characters for recognition of sandy turbidite environments: American Association of Petroleum Geologists Bulletin, v. 62, p. 912-931",
    note = "talkorigins\_source = {true}; raw\_reference = {Normark, W. R., 1978, Fan valleys, channels, and depositional lobes on modern submarine fans: characters for recognition of sandy turbidite environments: American Association of Petroleum Geologists Bulletin, v. 62, p. 912-931.}"
}

@misc{stanley1978sedimentation54,
    author = "Stanley, D. J. and Kelling, G",
    title = "Sedimentation in Submarine Canyons, Fans, and Trenches",
    year = "1978",
    howpublished = "Dowden, Hutchinson and Ross, Inc., 395 p",
    note = "talkorigins\_source = {true}; raw\_reference = {Stanley, D. J., and Kelling, G., 1978, Sedimentation in Submarine Canyons, Fans, and Trenches: Dowden, Hutchinson and Ross, Inc., 395 p.}"
}

@techreport{walker1978deepwater62,
    author = "Walker, R. G",
    title = "Deep-water sandstone facies and ancient submarine fans",
    year = "1978",
    howpublished = "models for exploration for stratigraphic traps: American Association of Petroleum Geologists Bulletin, v. 62, p. 932-966",
    note = "talkorigins\_source = {true}; raw\_reference = {Walker, R. G., 1978, Deep-water sandstone facies and ancient submarine fans: models for exploration for stratigraphic traps: American Association of Petroleum Geologists Bulletin, v. 62, p. 932-966.}"
}

@misc{woodbury1978gulf65,
    author = "Woodbury, H. O. and Spotts, J. H. and Akers, W. H",
    title = "Gulf of Mexico continental-slope sediments and sedimentation, in, 7 of AAPG Studies in Geology",
    year = "1978",
    howpublished = "p. 117-137",
    note = "talkorigins\_source = {true}; raw\_reference = {Woodbury, H. O., Spotts, J. H., and Akers, W. H., 1978, Gulf of Mexico continental-slope sediments and sedimentation, in, 7 of AAPG Studies in Geology: p. 117-137.}"
}

@techreport{buffler1979miocene15,
    author = "Buffler, R. T. and McMillen, K. J",
    title = "Miocene submarine fans in deep western Gulf of Mexico as interpreted from seismic reflection profiles",
    year = "1979",
    howpublished = "American Association of Petroleum Geologists Bulletin, v. 63, p. 426",
    note = "talkorigins\_source = {true}; raw\_reference = {Buffler, R. T., and McMillen, K. J., 1979, Miocene submarine fans in deep western Gulf of Mexico as interpreted from seismic reflection profiles: American Association of Petroleum Geologists Bulletin, v. 63, p. 426.}"
}

@article{christina1979the16,
    author = "Christina, C. C. and Martin, K. G",
    title = "The Lower Tuscaloosa trend of south- central Louisiana",
    year = "1979",
    journal = {You ain't seen nothing till you've seen the Tuscaloosa": Gulf Coast Association of Geological Societies Transactions, v. 29, p. 37-41},
    note = {talkorigins\_source = {true}; raw\_reference = {Christina, C. C., and Martin, K. G., 1979, The Lower Tuscaloosa trend of south- central Louisiana: "You ain't seen nothing till you've seen the Tuscaloosa": Gulf Coast Association of Geological Societies Transactions, v. 29, p. 37-41.}}
}

ABSTRACT The deep‐tow instrument package of Scripps Institution of Oceanography provides a unique opportunity to delineate small‐scale features of a size comparable to those features usually described from ancient deep‐sea fan deposits. On Navy Fan, the deep‐tow side‐scanning sonar readily detected steep channel walls and steps and terraces within channels. The most striking features observed in side‐scan are large crescentic depressions commonly occurring in groups. These appear to be large scours or flutes carved by turbidity currents. Four distinct acoustic facies were mapped on the basis of qualitative assessment of reflectivity of 4 kHz reflection profiles. There is a distinct increase in depth of acoustic penetration, number of sub‐bottom reflectors, and reflector continuity from the upper fan‐valley to the lower fan. These changes are accompanied by a decrease in surface relief. Navy Fan is made up of three active sectors. The active upper fan is dominated by a single channel with prominent levees that decrease in height downstream. The active mid‐fan region or suprafan is where sand is deposited. Well defined distributary channels with steps, terraces, and other mesotopography terminate in depositional lobes. Interchannel areas are rough, containing giant scours as well as other relief. The active lower fan accumulates mud and silt and is without resolvable surface morphology. The morphological features seen on Navy Fan other than levees, interchannel areas, and lobes are principally erosional. The distributary channels are up to 0.5 km wide and 5–15 m deep. Such features, because of their large size and low relief, are rarely completely exposed or easily detectable in ancient rock sequences. Some flute‐shaped scours are larger than channels in cross section but many are 5‐30 m across and 1‐2 m deep. If observed in ancient rocks transverse to palaeo‐current direction, they would perhaps be indistinguishable from channels. Surface sediment distribution combined with fan morphology can be used to relate modern sediments to facies models for ancient fan sediments. Gravel and sand occur in the upper valley, massive sand beds in the mid‐fan distributary channels, classical complete Bouma sequences on depositional lobes, incomplete Bouma sequences (lacking division a) on the lower mid‐fan, and Bouma sequence with lenticular shape or other limited extent on mid‐fan interchannel areas and on levees.

@article{doi101111j136530911979tb00971x,
    author = "Normark, William R. and Piper, David J. W. and Hess, Gordon R.",
    title = "Distributary channels, sand lobes, and mesotopography of Navy Submarine Fan, California Borderland, with applications to ancient fan sediments",
    year = "1979",
    journal = "Sedimentology",
    abstract = "ABSTRACT The deep‐tow instrument package of Scripps Institution of Oceanography provides a unique opportunity to delineate small‐scale features of a size comparable to those features usually described from ancient deep‐sea fan deposits. On Navy Fan, the deep‐tow side‐scanning sonar readily detected steep channel walls and steps and terraces within channels. The most striking features observed in side‐scan are large crescentic depressions commonly occurring in groups. These appear to be large scours or flutes carved by turbidity currents. Four distinct acoustic facies were mapped on the basis of qualitative assessment of reflectivity of 4 kHz reflection profiles. There is a distinct increase in depth of acoustic penetration, number of sub‐bottom reflectors, and reflector continuity from the upper fan‐valley to the lower fan. These changes are accompanied by a decrease in surface relief. Navy Fan is made up of three active sectors. The active upper fan is dominated by a single channel with prominent levees that decrease in height downstream. The active mid‐fan region or suprafan is where sand is deposited. Well defined distributary channels with steps, terraces, and other mesotopography terminate in depositional lobes. Interchannel areas are rough, containing giant scours as well as other relief. The active lower fan accumulates mud and silt and is without resolvable surface morphology. The morphological features seen on Navy Fan other than levees, interchannel areas, and lobes are principally erosional. The distributary channels are up to 0.5 km wide and 5–15 m deep. Such features, because of their large size and low relief, are rarely completely exposed or easily detectable in ancient rock sequences. Some flute‐shaped scours are larger than channels in cross section but many are 5‐30 m across and 1‐2 m deep. If observed in ancient rocks transverse to palaeo‐current direction, they would perhaps be indistinguishable from channels. Surface sediment distribution combined with fan morphology can be used to relate modern sediments to facies models for ancient fan sediments. Gravel and sand occur in the upper valley, massive sand beds in the mid‐fan distributary channels, classical complete Bouma sequences on depositional lobes, incomplete Bouma sequences (lacking division a) on the lower mid‐fan, and Bouma sequence with lenticular shape or other limited extent on mid‐fan interchannel areas and on levees.",
    url = "https://doi.org/10.1111/j.1365-3091.1979.tb00971.x",
    doi = "10.1111/j.1365-3091.1979.tb00971.x",
    openalex = "W2063746375",
    references = "doi101086627725, nelson1974depositional"
}

Five main facies of deep-water clastic rocks can be defined: classic turbidites, massive sandstones, pebbly sandstones, conglomerates, and debris flows (with slumps and slides). The classic turbidites consist of monotonously parallel-interbedded sandstones and shales without channeling; internal sedimentary structures include grading, parallel lamination, and cross-lamination. Massive sandstones are thicker, coarser, and commonly channelized. They lack the sedimentary structures of classic turbidites, but do contain evidence of dewatering during deposition. Pebbly sandstones tend to be well graded, and can contain parallel stratification and large-scale cross-stratification. Conglomerates are characterized by inverse and normal grading, parallel and cross-stratification, nd commonly have a preferred clast fabric (imbrication). Both the pebbly sandstones and conglomerates commonly are channelized. The facies can be fitted into a model of submarine-fan deposition. Modern fans are subdivided into an upper fan (suprafan), characterized by (1) a single deep channel with levees, (2) a middle fan, built up from suprafan lobes that periodically switch in position, and (3) a topographically smooth lower fan. The suprafan lobes have shallow, braided channels on their inner parts, but the outer suprafan lobes are smooth, and grade basinward into the smooth lower fan and basin plain. The smooth suprafan lobes and lower fan are characterized by deposition of the classic turbidite facies, and the braided part of the suprafan lobes by massive and pebbly sandstones. When one lobe is abandoned and another starts to prograde elsewhere, the first lobe is blanketed by mud, forming a potential stratigraphic trap. The upper-fan channel is an area of coarse sediment deposition, or conglomerates where gravel and boulders are supplied to the basin. During fan progradation, thickening- and coarsening-upward facies sequences can be formed in a manner analogous to those of deltas. Fan channels also can be abandoned progressively, forming thinning- and fining-upward sequences similar to those of fluvial or distributary channels. These sequences can be identified on electric logs. Where basin shales act as hydrocarbon-source areas, the classic turbidites can act as conduits, leading the hydrocarbons to the thicker, laterally coalesced massive and pebbly sandstones of the braided suprafan lobes. These bodies can be of the order of 25 km in diameter, and up to 100 m thick. The coarse deposits of the upper-fan channel also might form good reservoirs, being bounded by shales (levee deposits) on either side, and possibly by shales above if the fan-channel system is abandoned. Such channels can be tens of kilometers long, several kilometers wide, and a few hundred meters deep. Reservoirs may be present in all of these environments.

@article{doi1013062f9182e316ce11d78645000102c1865d,
    author = "Aalto, K. R.",
    title = "Deep-Water Sandstone Facies and Ancient Submarine Fans: Models for Exploration for Stratigraphic Traps: Discussion",
    year = "1979",
    journal = "AAPG Bulletin",
    abstract = "Five main facies of deep-water clastic rocks can be defined: classic turbidites, massive sandstones, pebbly sandstones, conglomerates, and debris flows (with slumps and slides). The classic turbidites consist of monotonously parallel-interbedded sandstones and shales without channeling; internal sedimentary structures include grading, parallel lamination, and cross-lamination. Massive sandstones are thicker, coarser, and commonly channelized. They lack the sedimentary structures of classic turbidites, but do contain evidence of dewatering during deposition. Pebbly sandstones tend to be well graded, and can contain parallel stratification and large-scale cross-stratification. Conglomerates are characterized by inverse and normal grading, parallel and cross-stratification, nd commonly have a preferred clast fabric (imbrication). Both the pebbly sandstones and conglomerates commonly are channelized. The facies can be fitted into a model of submarine-fan deposition. Modern fans are subdivided into an upper fan (suprafan), characterized by (1) a single deep channel with levees, (2) a middle fan, built up from suprafan lobes that periodically switch in position, and (3) a topographically smooth lower fan. The suprafan lobes have shallow, braided channels on their inner parts, but the outer suprafan lobes are smooth, and grade basinward into the smooth lower fan and basin plain. The smooth suprafan lobes and lower fan are characterized by deposition of the classic turbidite facies, and the braided part of the suprafan lobes by massive and pebbly sandstones. When one lobe is abandoned and another starts to prograde elsewhere, the first lobe is blanketed by mud, forming a potential stratigraphic trap. The upper-fan channel is an area of coarse sediment deposition, or conglomerates where gravel and boulders are supplied to the basin. During fan progradation, thickening- and coarsening-upward facies sequences can be formed in a manner analogous to those of deltas. Fan channels also can be abandoned progressively, forming thinning- and fining-upward sequences similar to those of fluvial or distributary channels. These sequences can be identified on electric logs. Where basin shales act as hydrocarbon-source areas, the classic turbidites can act as conduits, leading the hydrocarbons to the thicker, laterally coalesced massive and pebbly sandstones of the braided suprafan lobes. These bodies can be of the order of 25 km in diameter, and up to 100 m thick. The coarse deposits of the upper-fan channel also might form good reservoirs, being bounded by shales (levee deposits) on either side, and possibly by shales above if the fan-channel system is abandoned. Such channels can be tens of kilometers long, several kilometers wide, and a few hundred meters deep. Reservoirs may be present in all of these environments.",
    url = "https://doi.org/10.1306/2f9182e3-16ce-11d7-8645000102c1865d",
    doi = "10.1306/2f9182e3-16ce-11d7-8645000102c1865d",
    openalex = "W2056452793",
    references = "doi1010160016714277900096, doi101086625710, doi101111j136530911975tb00290x, doi101111j136530911976tb00051x, doi101111j136530911977tb00122x, doi101130001676061969801859dfpap20co2, doi10113000167606197586737gfmfrc20co2, doi1013065d25c0f916c111d78645000102c1865d, doi1013065d25c2d316c111d78645000102c1865d, doi1013065d25c61516c111d78645000102c1865d, doi1013065d25cc7916c111d78645000102c1865d, doi10130674d7262b2b2111d78648000102c1865d, doi102110scn7502, openalexw3120543430, paine1968stratigraphy"
}

@article{foss1979depositional20,
    author = "Foss, D. C",
    title = "Depositional environment of Woodbine sandstones, Polk County, Texas",
    year = "1979",
    journal = "Gulf Coast Association of Geological Societies Transactions, v. 29, p. 83-94",
    note = "talkorigins\_source = {true}; raw\_reference = {Foss, D. C., 1979, Depositional environment of Woodbine sandstones, Polk County, Texas: Gulf Coast Association of Geological Societies Transactions, v. 29, p. 83-94.}"
}

@techreport{heritier1979frigg23,
    author = "Heritier, F. E. and Lossel, P. and Wathne, E",
    title = "Frigg Field - large submarine fan trap in lower Eocene rocks of the North Sea",
    year = "1979",
    howpublished = "American Association of Petroleum Geologists Bulletin, v. 63, p. 1999-2020",
    note = "talkorigins\_source = {true}; raw\_reference = {Heritier, F. E., Lossel, P., and Wathne, E., 1979, Frigg Field - large submarine fan trap in lower Eocene rocks of the North Sea: American Association of Petroleum Geologists Bulletin, v. 63, p. 1999-2020.}"
}

@misc{laporte1979ancient28,
    author = "Laporte, L. F",
    title = "Ancient Environments [2nd ed.]",
    year = "1979",
    howpublished = "Englewood Cliffs, New Jersey, Prentice-Hall",
    note = "talkorigins\_source = {true}; raw\_reference = {Laporte, L. F., 1979, Ancient Environments [2nd ed.]: Englewood Cliffs, New Jersey, Prentice-Hall.}"
}

@misc{moore1979investigation37,
    author = "Moore, G. T. and Woodbury, H. O. and Worzel, J. L. and Watkins, J. S. and Starke, G. W",
    title = "Investigation of the Mississippi Fan, Gulf of Mexico, in Geological and Geophysical Investigations of Continental Margins, 29 of AAPG Memoirs",
    year = "1979",
    howpublished = "p. 383-402",
    note = "talkorigins\_source = {true}; raw\_reference = {Moore, G. T., Woodbury, H. O., Worzel, J. L., Watkins, J. S., and Starke, G. W., 1979, Investigation of the Mississippi Fan, Gulf of Mexico, in Geological and Geophysical Investigations of Continental Margins, 29 of AAPG Memoirs: p. 383-402.}"
}

@book{mutti1979turbidites38,
    author = "Mutti, E",
    title = "Turbidites et cones sous-marins profonds, in Sedimemtation detritique (fluviatile, littorale et marine), 1979 of Institut de Geologie de l'University de Fribourg, Short Course",
    year = "1979",
    publisher = "Fribourg, Institut de Geologie de l'University de Fribourg, p. 353-419",
    note = "talkorigins\_source = {true}; raw\_reference = {Mutti, E., 1979, Turbidites et cones sous-marins profonds, in Sedimemtation detritique (fluviatile, littorale et marine), 1979 of Institut de Geologie de l'University de Fribourg, Short Course: Fribourg, Institut de Geologie de l'University de Fribourg, p. 353-419.}"
}

@article{nardin1979a42,
    author = "Nardin, T. R. and Hein, F. J. and Gorsline, D. S. and Edwards, B. D",
    title = "A review of mass movement processes, sediment and acoustic characteristics, and contrasts in slope and base-of-slope systems versus canyon-fan-basin floor systems, in Geology of Continental Slopes",
    year = "1979",
    journal = "SEPM Special Publication 27, p. 61-73",
    note = "talkorigins\_source = {true}; raw\_reference = {Nardin, T. R., Hein, F. J., Gorsline, D. S., and Edwards, B. D., 1979, A review of mass movement processes, sediment and acoustic characteristics, and contrasts in slope and base-of-slope systems versus canyon-fan-basin floor systems, in Geology of Continental Slopes: SEPM Special Publication 27, p. 61-73.}"
}

@article{openalexw1560313239,
    author = "Hendry, Hugh E.",
    title = "Sedimentation in Submarine Canyons, Fans and Trenches",
    year = "1979",
    journal = "Geoscience Canada",
    openalex = "W1560313239"
}

@article{doi1010160037073880900524,
    author = "Stow, Dorrik A. V. and Shanmugam, Ganapathy",
    title = "Sequence of structures in fine-grained turbidites: Comparison of recent deep-sea and ancient flysch sediments",
    year = "1980",
    journal = "Sedimentary Geology",
    url = "https://doi.org/10.1016/0037-0738(80)90052-4",
    doi = "10.1016/0037-0738(80)90052-4",
    openalex = "W2025308240",
    references = "doi1010160012825279900023, doi1010160037073874900177, doi10108000288306196910420225, doi101111j136530911977tb00122x, doi101111j136530911979tb00915x, doi101111j136530911980tb01156x, doi101144gsjgs13410019, doi10130674d716452b2111d78648000102c1865d, doi10130674d71adc2b2111d78648000102c1865d, openalexw2993540452, openalexw3120543430"
}

Canyon Wall Sedimentation and Lateral Infill: Some Ancient Examples. Smithsonian Contributions to the Marine Sciences, number 4, 32 pages, 17 figures, 1980.-Submarine canyon wall and tributary sequences at three Annot Sandstone localities in the French Maritime Alps record early-stage resedimentation events in proximal sectors of the Tertiary Annot Basin. Canyon margin lithofacies are distinctive in that they comprise a more variable suite of stratal types than intracanyon slope, canyon axis, distal fan and basin series of the same formation. Characteristic criteria include the highly variable geometry and spatial distribution of the series of strata, irregular bedding thickness, paleocurrent directions that diverge from the predominant regional patterns, and discontinuities within the formation and between the Annot Sandstone and the older marine shale series (Eocene Marnes bleues) forming the canyon margins. Three distinctive sandstone stratification types dominate the "grs d'Annot" canyon wall association: type 1 units, moderately to well-stratified and massive (often amalgamated), emplaced by debris flow and a continuum of sediment-fluid flow mechanism, not specifically identifiable in the field; some thick sand layers may represent deposition as 'quick' beds from high-concentration underflows, possibly gradational between liquified and turbidity current flows; type 2 units, displaying slightly to extensive deformed horizons within but not throughout the beds, probably are related to liquefied flow and post-depositional liquefaction processes; and type 3 units, emplaced 'en masse' and in some cases showing complete disruption of primary stratification (chaotic bedding), are identified as slides and slumps. In addition to the three above types, lower proportions of graded, generally thin 'classic' sandstone turbidites (T+, Tp, and Tp-.) and mudstone turbidites are recognized.

@article{doi105479si019607684,
    author = "Stanley, Daniel Jean",
    title = "Submarine Canyon Wall Sedimentation and Lateral Infill: Some Ancient Examples",
    year = "1980",
    journal = "Smithsonian contributions to the marine sciences",
    abstract = {Canyon Wall Sedimentation and Lateral Infill: Some Ancient Examples. Smithsonian Contributions to the Marine Sciences, number 4, 32 pages, 17 figures, 1980.-Submarine canyon wall and tributary sequences at three Annot Sandstone localities in the French Maritime Alps record early-stage resedimentation events in proximal sectors of the Tertiary Annot Basin. Canyon margin lithofacies are distinctive in that they comprise a more variable suite of stratal types than intracanyon slope, canyon axis, distal fan and basin series of the same formation. Characteristic criteria include the highly variable geometry and spatial distribution of the series of strata, irregular bedding thickness, paleocurrent directions that diverge from the predominant regional patterns, and discontinuities within the formation and between the Annot Sandstone and the older marine shale series (Eocene Marnes bleues) forming the canyon margins. Three distinctive sandstone stratification types dominate the "grs d'Annot" canyon wall association: type 1 units, moderately to well-stratified and massive (often amalgamated), emplaced by debris flow and a continuum of sediment-fluid flow mechanism, not specifically identifiable in the field; some thick sand layers may represent deposition as 'quick' beds from high-concentration underflows, possibly gradational between liquified and turbidity current flows; type 2 units, displaying slightly to extensive deformed horizons within but not throughout the beds, probably are related to liquefied flow and post-depositional liquefaction processes; and type 3 units, emplaced 'en masse' and in some cases showing complete disruption of primary stratification (chaotic bedding), are identified as slides and slumps. In addition to the three above types, lower proportions of graded, generally thin 'classic' sandstone turbidites (T+, Tp, and Tp-.) and mudstone turbidites are recognized.},
    url = "https://doi.org/10.5479/si.01960768.4",
    doi = "10.5479/si.01960768.4",
    openalex = "W2088468668",
    references = "carlson1977submarine, doi101098rsta19560020, doi101111j136530911975tb00290x, doi1013062f9182e316ce11d78645000102c1865d, doi10130674d7262b2b2111d78648000102c1865d, doi101306c1ea4f7716c911d78645000102c1865d, doi102110scn8403, openalexw1560313239, openalexw2993540452, openalexw3120543430, openalexw580680426"
}

@misc{fritz1980reinterpretation21,
    author = "Fritz, W. J",
    title = {Reinterpretation of the depositional environment of the Yellowstone "fossil forests},
    year = "1980",
    howpublished = "Geology, v. 8, p. 309-313",
    note = {talkorigins\_source = {true}; raw\_reference = {Fritz, W. J., 1980, Reinterpretation of the depositional environment of the Yellowstone "fossil forests": Geology, v. 8, p. 309-313.}}
}

@article{link1980the34,
    author = "Link, M. H. and Nilsen, T. H",
    title = "The Rocks Sandstone, an Eocene sand-rich deep-sea fan deposit, northern Santa Lucia range, California",
    year = "1980",
    journal = "Journal of Sedimentary Petrology, v. 50, p. 583-601",
    note = "talkorigins\_source = {true}; raw\_reference = {Link, M. H., and Nilsen, T. H., 1980, The Rocks Sandstone, an Eocene sand-rich deep-sea fan deposit, northern Santa Lucia range, California: Journal of Sedimentary Petrology, v. 50, p. 583-601.}"
}

@techreport{nilsen1980modern46,
    author = "Nilsen, T. H",
    title = "Modern and ancient submarine fans",
    year = "1980",
    howpublished = "Discussions of papers by R.G. Walker aand W.R. Normark: American Association of Petroleum Geologists Bulletin, v. 64, p. 1094-1101",
    note = "talkorigins\_source = {true}; raw\_reference = {Nilsen, T. H., 1980, Modern and ancient submarine fans: Discussions of papers by R.G. Walker aand W.R. Normark: American Association of Petroleum Geologists Bulletin, v. 64, p. 1094-1101.}"
}

@techreport{normark1980modern49,
    author = "Normark, W. R",
    title = "Modern and ancient submarine fans",
    year = "1980",
    howpublished = "reply: American Association of Petroleum Geologists Bulletin, v. 64, p. 1108-1112",
    note = "talkorigins\_source = {true}; raw\_reference = {Normark, W. R., 1980, Modern and ancient submarine fans: reply: American Association of Petroleum Geologists Bulletin, v. 64, p. 1108-1112.}"
}

@article{hiscott1981deep24,
    author = "Hiscott, R. N",
    title = "Deep sea fan deposits in the Macigno Formation (Middle- Upper Oilgocene) of the Gordana Valley, Northern Appennines, Italy",
    year = "1981",
    journal = "Discussion: Journal of Sedimentary Petrology, v. 51, p. 1015-1021",
    note = "talkorigins\_source = {true}; raw\_reference = {Hiscott, R. N., 1981, Deep sea fan deposits in the Macigno Formation (Middle- Upper Oilgocene) of the Gordana Valley, Northern Appennines, Italy: Discussion: Journal of Sedimentary Petrology, v. 51, p. 1015-1021.}"
}

@misc{kelts1981turbidites26,
    author = "Kelts, K. and Arthur, M. A",
    title = "Turbidites after ten years of deep-sea drilling - wringing out the mop?, in Warme, J. E., Douglas, R. G., and Winterer, E. L., eds., The Deep Sea Drilling Project",
    year = "1981",
    howpublished = "A decade of progress, 32 of SEPM Special Publication: SEPM, p. 91-127",
    note = "talkorigins\_source = {true}; raw\_reference = {Kelts, K., and Arthur, M. A., 1981, Turbidites after ten years of deep-sea drilling - wringing out the mop?, in Warme, J. E., Douglas, R. G., and Winterer, E. L., eds., The Deep Sea Drilling Project: A decade of progress, 32 of SEPM Special Publication: SEPM, p. 91-127.}"
}

@misc{retallack1981comment53,
    author = "Retallack, G. and Fritz, W. J",
    title = {Comment and reply on "Reinterpretation of the depositional environment of the Yellowstone fossil forests},
    year = "1981",
    howpublished = "Geology, v. 9, p. 52-54",
    note = {talkorigins\_source = {true}; raw\_reference = {Retallack, G., and Fritz, W. J., 1981, Comment and reply on "Reinterpretation of the depositional environment of the Yellowstone fossil forests": Geology, v. 9, p. 52-54.}}
}

Sandstone Depositional Environments has proven to be one of AAPG's all-time best sellers, with multiple reprints and extensive use as a university textbook. The volume is specifically designed for the non-sedimentologist, the petroleum geologist, or the field geologist who needs to use sandstone depositional environments in facies reconstruction and environmental interpretations. Prediction of subsurface sandstone trends, diagenetic style, and continuity of reservoir porosity is strongly dependent on an understanding of original depositional environments. The volume consists of twelve chapters, each covering a major environmental setting for sandstone deposition from terrestrial to deep marine (glacial, eolian, alluvial fan, lacustrine, fluvial, deltaic, estuarine, tidal flat, barrier island, continental shelf, continental slope, and submarine fan). For each environment the modern depositional processes are described and compared to subsurface examples, with abundant illustrations and photographs. Different scales and perspectives are reviewed, using aerial photos, maps, seismic, cross sections, outcrops, cores, and thin sections. Each chapter is organized in a manner that it can be used effectively and independently for teaching purposes or as an analog reference for field study and subsurface interpretation.

@book{doi101306m31424,
    author = "Scholle, Peter A. and Spearing, Darwin",
    title = "Sandstone Depositional Environments",
    year = "1982",
    booktitle = "American Association of Petroleum Geologists eBooks",
    abstract = "Sandstone Depositional Environments has proven to be one of AAPG's all-time best sellers, with multiple reprints and extensive use as a university textbook. The volume is specifically designed for the non-sedimentologist, the petroleum geologist, or the field geologist who needs to use sandstone depositional environments in facies reconstruction and environmental interpretations. Prediction of subsurface sandstone trends, diagenetic style, and continuity of reservoir porosity is strongly dependent on an understanding of original depositional environments. The volume consists of twelve chapters, each covering a major environmental setting for sandstone deposition from terrestrial to deep marine (glacial, eolian, alluvial fan, lacustrine, fluvial, deltaic, estuarine, tidal flat, barrier island, continental shelf, continental slope, and submarine fan). For each environment the modern depositional processes are described and compared to subsurface examples, with abundant illustrations and photographs. Different scales and perspectives are reviewed, using aerial photos, maps, seismic, cross sections, outcrops, cores, and thin sections. Each chapter is organized in a manner that it can be used effectively and independently for teaching purposes or as an analog reference for field study and subsurface interpretation.",
    url = "https://doi.org/10.1306/m31424",
    doi = "10.1306/m31424",
    openalex = "W1866543612"
}

@misc{harms1982structures22,
    author = "Harms, J. C. and Southard, J. B. and Walker, R. G",
    title = "Structures and sequences in clastic rocks",
    year = "1982",
    howpublished = "Society of Economic Paleontologists and Mineralogists, Short Course \#9. Variously paginated",
    note = "talkorigins\_source = {true}; raw\_reference = {Harms, J. C., Southard, J. B., and Walker, R. G., 1982, Structures and sequences in clastic rocks. Society of Economic Paleontologists and Mineralogists, Short Course \#9. Variously paginated.}"
}

@misc{howell1982sedimentology25,
    author = "Howell, D. G. and Normark, W. R",
    title = "Sedimentology of submarine fans, in Scholle, P. A., and Spearing, D. R., eds., Sandstone depositional environments, 31 of AAPG Memoirs",
    year = "1982",
    howpublished = "Tulsa, OK, AAPG, p. 365-404",
    note = "talkorigins\_source = {true}; raw\_reference = {Howell, D. G., and Normark, W. R., 1982, Sedimentology of submarine fans, in Scholle, P. A., and Spearing, D. R., eds., Sandstone depositional environments, 31 of AAPG Memoirs: Tulsa, OK, AAPG, p. 365-404.}"
}

@book{leipzig1982stratigraphy29,
    author = "Leipzig, M. R",
    title = "Stratigraphy, Sedimentation and Depositional Environments of the Late Cretaceous Pictured Cliffs Sandstone, Fruitland Formation, Kirtland Shale and Early Tertiary Ojo Alamo Sandstone; Eastern San Juan Basin, New Mexico [MS dissert.]",
    year = "1982",
    publisher = "University of Wisconsin-Milwaukee, 555 p",
    note = "talkorigins\_source = {true}; raw\_reference = {Leipzig, M. R., 1982, Stratigraphy, Sedimentation and Depositional Environments of the Late Cretaceous Pictured Cliffs Sandstone, Fruitland Formation, Kirtland Shale and Early Tertiary Ojo Alamo Sandstone; Eastern San Juan Basin, New Mexico [MS dissert.]: University of Wisconsin-Milwaukee, 555 p.}"
}

@techreport{link1982sedimentology35,
    author = "Link, M. H. and Welton, J. E",
    title = "Sedimentology and reservoir potential of Matilija Sandstone",
    year = "1982",
    howpublished = "an Eocene sand-rich deep-sea fan and shallow marine complex, southern California: American Association of Petroleum Geologists Bulletin, v. 66, p. 1514-1534",
    note = "talkorigins\_source = {true}; raw\_reference = {Link, M. H., and Welton, J. E., 1982, Sedimentology and reservoir potential of Matilija Sandstone: an Eocene sand-rich deep-sea fan and shallow marine complex, southern California: American Association of Petroleum Geologists Bulletin, v. 66, p. 1514-1534.}"
}

@misc{tillman1982deep57,
    author = "Tillman, R. W. and Ali, S. A",
    title = "Deep water canyons, fans and facies",
    year = "1982",
    howpublished = "models for stratigraphic trap exploration, 26 of AAPG Reprint Series: Tulsa, OK, American Association of Petroleum Geologists, 596 p",
    note = "talkorigins\_source = {true}; raw\_reference = {Tillman, R. W., and Ali, S. A., 1982, Deep water canyons, fans and facies: models for stratigraphic trap exploration, 26 of AAPG Reprint Series: Tulsa, OK, American Association of Petroleum Geologists, 596 p.}"
}

ABSTRACT The late Pleistocene and Holocene stratigraphy of Navy Fan is mapped in detail from more than 100 cores. Thirteen 14 C dates of plant detritus and of organic‐rich mud beds show that a marked change in sediment supply from sandy to muddy turbidites occurred between 9000 and 12,000 years ago. They also confirm the correlation of several individual depositional units. The sediment dispersal pattern is primarily controlled by basin configuration and fan morphology, particularly the geometry of distributary channels, which show abrupt 60° bends related to the Pleistocene history of lobe progradation. The Holocene turbidity currents are depositing on, and modifying only slightly, a relict Pleistocene morphology. The uppermost turbidite is a thin sand to mud bed on the upper‐fan valley levées and on parts of the mid‐fan. Most of its sediment volume is in a mud bed on the lower fan and basin plain downslope from a sharp bend in the mid‐fan distributary system. Little sediment occurs farther downstream within this distributary system. It appears that most of the turbidity current overtopped the levée at the channel bend, a process referred to as flow stripping. The muddy upper part of the flow continued straight down to the basin plain. The residual more sandy base of the flow in the distributary channel was not thick enough to maintain itself as gradient decreased and the channel opened out on to the mid‐fan lobe. Flow stripping may occur in any turbidity current that is thick relative to channel depth and that flows in a channel with sharp bends. Where thick sandy currents are stripped, levée and mid‐fan erosion may occur, but the residual current in the channel will lose much of its power and deposit rapidly. In thick muddy currents, progressive overflow of mud will cause less declaration of the residual channelised current. Thus both size and sand‐to‐mud ratio of turbidity currents feeding a fan are important factors controlling morphologic features and depositional areas on fans. The size‐frequency variation for different types of turbidity currents is estimated from the literature and related to the evolution of fan morphology.

@article{doi101111j136530911983tb00702x,
    author = "Piper, David J. W. and Normark, William R.",
    title = "Turbidite depositional patterns and flow characteristics, Navy Submarine Fan, California Borderland",
    year = "1983",
    journal = "Sedimentology",
    abstract = "ABSTRACT The late Pleistocene and Holocene stratigraphy of Navy Fan is mapped in detail from more than 100 cores. Thirteen 14 C dates of plant detritus and of organic‐rich mud beds show that a marked change in sediment supply from sandy to muddy turbidites occurred between 9000 and 12,000 years ago. They also confirm the correlation of several individual depositional units. The sediment dispersal pattern is primarily controlled by basin configuration and fan morphology, particularly the geometry of distributary channels, which show abrupt 60° bends related to the Pleistocene history of lobe progradation. The Holocene turbidity currents are depositing on, and modifying only slightly, a relict Pleistocene morphology. The uppermost turbidite is a thin sand to mud bed on the upper‐fan valley levées and on parts of the mid‐fan. Most of its sediment volume is in a mud bed on the lower fan and basin plain downslope from a sharp bend in the mid‐fan distributary system. Little sediment occurs farther downstream within this distributary system. It appears that most of the turbidity current overtopped the levée at the channel bend, a process referred to as flow stripping. The muddy upper part of the flow continued straight down to the basin plain. The residual more sandy base of the flow in the distributary channel was not thick enough to maintain itself as gradient decreased and the channel opened out on to the mid‐fan lobe. Flow stripping may occur in any turbidity current that is thick relative to channel depth and that flows in a channel with sharp bends. Where thick sandy currents are stripped, levée and mid‐fan erosion may occur, but the residual current in the channel will lose much of its power and deposit rapidly. In thick muddy currents, progressive overflow of mud will cause less declaration of the residual channelised current. Thus both size and sand‐to‐mud ratio of turbidity currents feeding a fan are important factors controlling morphologic features and depositional areas on fans. The size‐frequency variation for different types of turbidity currents is estimated from the literature and related to the evolution of fan morphology.",
    url = "https://doi.org/10.1111/j.1365-3091.1983.tb00702.x",
    doi = "10.1111/j.1365-3091.1983.tb00702.x",
    openalex = "W2103765846",
    references = "doi101016001174717090001x, doi1010160019103580900974, doi1010160025322776900633, doi101086627725, doi101111j136530911979tb00971x, doi10113000167606197485859lcotpe20co2, doi101130001676061976871291cotthb20co2, doi101130001676061979901165bsthap20co2, doi101306212f79b42b2411d78648000102c1865d, openalexw3120543430"
}

Summary Based on a large amount of published data and stimulated by the papers and discussion at the International Workshop on Fine-Grained Sediments held in Halifax, Canada in August 1982, we have attempted a synthesis of deep-water fine-grained sediment facies. Three main facies groups related to depositional processes can be identified: turbidites, contourites and pelagites/hemipelagites. There is a continuum between the different processes and hence a continuum between facies. Nevertheless, it is possible to define several distinct facies models within each of these groups on the basis of sedimentary structures, texture and composition, and to provisionally interpret these in terms of depositional hydrodynamics. Patterns of horizontal and vertical facies distribution can be related to depositional subenvironments. There is much variability within and departure from the facies models we propose, and many interesting and problematic areas of research remain in the quest for better understanding of deep-water fine-grained sediments.

@article{doi101144gslsp19840150138,
    author = "Stow, Dorrik A. V. and Piper, David J. W.",
    title = "Deep-water fine-grained sediments: facies models",
    year = "1984",
    journal = "Geological Society London Special Publications",
    abstract = "Summary Based on a large amount of published data and stimulated by the papers and discussion at the International Workshop on Fine-Grained Sediments held in Halifax, Canada in August 1982, we have attempted a synthesis of deep-water fine-grained sediment facies. Three main facies groups related to depositional processes can be identified: turbidites, contourites and pelagites/hemipelagites. There is a continuum between the different processes and hence a continuum between facies. Nevertheless, it is possible to define several distinct facies models within each of these groups on the basis of sedimentary structures, texture and composition, and to provisionally interpret these in terms of depositional hydrodynamics. Patterns of horizontal and vertical facies distribution can be related to depositional subenvironments. There is much variability within and departure from the facies models we propose, and many interesting and problematic areas of research remain in the quest for better understanding of deep-water fine-grained sediments.",
    url = "https://doi.org/10.1144/gsl.sp.1984.015.01.38",
    doi = "10.1144/gsl.sp.1984.015.01.38",
    openalex = "W2040337214",
    references = "doi1010079783642758294, doi1010160025322767900515, doi1010160025322776900839, doi1010160025322778900944, doi1010160025322779900860, doi1010160037073880900524, doi10108000288306196910420225, doi101086627725, doi101306c1ea4f7716c911d78645000102c1865d"
}

@techreport{leipzig1984stratigraphy30,
    author = "Leipzig, M. R",
    title = "Stratigraphy, Sedimentology and Depositional Environments of the Late Cretaceous/Early Tertiary Transition, Eastern San Juan Basin, New Mexico",
    year = "1984",
    howpublished = "New Mexico Bureau of Mines and Mineral Resources Bulletin, v. 142, no. 5, p. 109-256",
    note = "talkorigins\_source = {true}; raw\_reference = {Leipzig, M. R., 1984, Stratigraphy, Sedimentology and Depositional Environments of the Late Cretaceous/Early Tertiary Transition, Eastern San Juan Basin, New Mexico: New Mexico Bureau of Mines and Mineral Resources Bulletin, v. 142, no. 5, p. 109-256.}"
}

@book{bouma1986submarine14,
    author = "Bouma, A. and Normark, W. R. and Barnes, N. E",
    title = "Submarine fans and related turbidite systems",
    year = "1986",
    publisher = "New York, Springer Verlag, 351 p",
    note = "talkorigins\_source = {true}; raw\_reference = {Bouma, A., Normark, W. R., and Barnes, N. E., 1986, Submarine fans and related turbidite systems: New York, Springer Verlag, 351 p.}"
}

ABSTRACT New eustatic concepts developed primarily at Exxon Production Research complement the many technical improvements in seismic data and allow us to better predict reservoir and seal in Gulf of Mexico sediments. We can now more successfully integrate biostratigraphic and environmental interpretation of well data with sequence and seismic facies interpretation by using a succession of environmentally related chronostratigraphic units, called systems tracts. Of particular interest, because of their economic potential, are deposits formed during eustatic lowstands, the lowstand systems tract. Three principal phases of lowstand deposition are recognized: basin floor fan, slope fan and prograding complex. Basin floor fans in the Gulf of Mexico typically occur in topographic lows and consist of sands of high porosity and permeability in multilayered beds with gross thickness of 5 to 50 meters. Slope fans contain discrete sands in submarine channels, typically 5 to 40 meters thick with good porosity and permeability. Overbank sands associated with the slope fan are thin (1–30 cm), but may have excellent porosity and permeability. Rapid sedimentation during late Pliocene and Pleistocene time has also resulted in major accumulation of slump deposits, primarily associated with the slope fan. Prograding complex sands occur as stacked sands in shallow marine to fluvial environments deposited at or below the previous shelf edge, and in turbidite fans at the toes of the prograding clinoforms. Stratigraphic entrapment by internal shale seals is characteristic of many of the deep-water lowstand deposits. Sands of the shallow water portion of the prograding complex generally require structural entrapment. INTRODUCTION Interpretation of Gulf of Mexico shelf, slope and basin sediments is moving into a new era. The combination of improved seismic technology with the new "sequence stratigraphy" (Vail, 1988) significantly enhances our ability to predict reservoir and seal in both stratigraphic and structural prospects. New seismic technology applied to stratigraphic interpretation centers on the routine use of 3-D surveys, with their enhanced resolution and on improved migration of stratigraphic as well as structural events. Emphasis on direct detection and prediction of hydrocarbons from seismic data has produced a bonus for stratigraphic analysis through improved control over phase and amplitude during processing. Finally, interactive interpretation of both seismic sections and of quantitative seismic attributes, integrated with well data via improved synthetic seismograms, opens marvelous new doors for the modern Gulf Coast explorationist. The new eustatic concepts of sedimentary response to cycles of sea level change complement this technical progress. These concepts have particular application in the Gulf of Mexico because:High rates of sedimentation of prograding siliciclastic sediments into a deep basin provide a wide variety of seismically resolvable sedimentary responses to cyclic sea level changes.Structural deformation contemporaneous with sedimentation enhances the thickness and the seismic expression of the resulting deposits.The relationship of cyclical alternation of continental glaciation and of warm relatively ice-free times during the Pleistocene is well established and provides a laboratory for the study of the associated effects of eustatic sea level cycles on sedimentation.

@article{doi1040435695ms,
    author = "Sangree, J. B. and Vail, P.A. and Sneider, A.M.",
    title = "Evolution Of Facies Interpretation Of The Shelf-Slope: Application Of The New Eustatic Framework To The Gulf Of Mexico",
    year = "1988",
    journal = "Offshore Technology Conference",
    abstract = {ABSTRACT New eustatic concepts developed primarily at Exxon Production Research complement the many technical improvements in seismic data and allow us to better predict reservoir and seal in Gulf of Mexico sediments. We can now more successfully integrate biostratigraphic and environmental interpretation of well data with sequence and seismic facies interpretation by using a succession of environmentally related chronostratigraphic units, called systems tracts. Of particular interest, because of their economic potential, are deposits formed during eustatic lowstands, the lowstand systems tract. Three principal phases of lowstand deposition are recognized: basin floor fan, slope fan and prograding complex. Basin floor fans in the Gulf of Mexico typically occur in topographic lows and consist of sands of high porosity and permeability in multilayered beds with gross thickness of 5 to 50 meters. Slope fans contain discrete sands in submarine channels, typically 5 to 40 meters thick with good porosity and permeability. Overbank sands associated with the slope fan are thin (1–30 cm), but may have excellent porosity and permeability. Rapid sedimentation during late Pliocene and Pleistocene time has also resulted in major accumulation of slump deposits, primarily associated with the slope fan. Prograding complex sands occur as stacked sands in shallow marine to fluvial environments deposited at or below the previous shelf edge, and in turbidite fans at the toes of the prograding clinoforms. Stratigraphic entrapment by internal shale seals is characteristic of many of the deep-water lowstand deposits. Sands of the shallow water portion of the prograding complex generally require structural entrapment. INTRODUCTION Interpretation of Gulf of Mexico shelf, slope and basin sediments is moving into a new era. The combination of improved seismic technology with the new "sequence stratigraphy" (Vail, 1988) significantly enhances our ability to predict reservoir and seal in both stratigraphic and structural prospects. New seismic technology applied to stratigraphic interpretation centers on the routine use of 3-D surveys, with their enhanced resolution and on improved migration of stratigraphic as well as structural events. Emphasis on direct detection and prediction of hydrocarbons from seismic data has produced a bonus for stratigraphic analysis through improved control over phase and amplitude during processing. Finally, interactive interpretation of both seismic sections and of quantitative seismic attributes, integrated with well data via improved synthetic seismograms, opens marvelous new doors for the modern Gulf Coast explorationist. The new eustatic concepts of sedimentary response to cycles of sea level change complement this technical progress. These concepts have particular application in the Gulf of Mexico because:High rates of sedimentation of prograding siliciclastic sediments into a deep basin provide a wide variety of seismically resolvable sedimentary responses to cyclic sea level changes.Structural deformation contemporaneous with sedimentation enhances the thickness and the seismic expression of the resulting deposits.The relationship of cyclical alternation of continental glaciation and of warm relatively ice-free times during the Pleistocene is well established and provides a laboratory for the study of the associated effects of eustatic sea level cycles on sedimentation.},
    url = "https://doi.org/10.4043/5695-ms",
    doi = "10.4043/5695-ms",
    openalex = "W1976977730"
}

@phdthesis{leipzig1989the31,
    author = "Leipzig, M. R",
    title = "The Stratigraphy, Sedimentology and Depositional Environments of the Late Cretaceous Pictured Cliffs Sandstone, Fruitland and Kirtland Formations and the Early Tertiary Ojo Alamo Sandstone. Eastern San Juan Basin, New Mexico. The Saga Continues [PhD dissert.]",
    year = "1989",
    publisher = "University of Wisconsin - Milwaukee and Madison, 978 p",
    note = "talkorigins\_source = {true}; raw\_reference = {Leipzig, M. R., 1989, The Stratigraphy, Sedimentology and Depositional Environments of the Late Cretaceous Pictured Cliffs Sandstone, Fruitland and Kirtland Formations and the Early Tertiary Ojo Alamo Sandstone. Eastern San Juan Basin, New Mexico. The Saga Continues [PhD dissert.]: University of Wisconsin - Milwaukee and Madison, 978 p.}"
}

ABSTRACT The Mississippi Fan is a large, mud-dominated submarine fan over 4 km thick that was deposited in the deep Gulf of Mexico during the late Pliocene and Pleistocene. Analysis of 19000 km of multifold seismic data across the fan defined 17 seismic sequences, each characterized by a series of channel, levee, and associated overbank deposits, along with other mass transport deposits. At the base of nine sequences are a series of seismic facies consisting of mounded, hummocky, chaotic, and subparallel reflections, which constitute 10–20% of the sediments in the sequence. These facies are externally mounded in cross section and occur in two general regions of the fan. In the upper and middle fan, they occur below channels and are elongated in shape, mimicking the channel’s distribution. In the middle to lower fan, they have a fan-shaped distribution, increasing in width downfan. These facies are interpreted to have formed as disorganized slides, debris flows, and turbidites, and are informally called mass transport complexes. Overlying this basal interval and characteristic of all sequences are well-developed channel-levee systems, which constitute 80–90% of the fan’s sediments. Channels consist of high-amplitude, subparallel reflections. Levee sediments have subparallel reflections that have moderate to high amplitudes at the base changing upward to low amplitude. The vertical change in amplitude may reflect a decrease in the grain size and bed thickness of the levee sediments. Overbank sediments consist of interbedded subparallel to hummocky and mounded reflections, suggesting both turbidites derived from the channel, as well as slides and debris flows derived from the slope. Pliocene–Pleistocene eustatic cycles are interpreted to have been the major factor controlling the timing and style of sedimentation in the fan. Mass transport complexes are interpreted to have formed during a lowering of sea level, and reflect sediments derived from retrogressive slumping during the formation of submarine canyons in the upper slope and outer shelf. Channel-levee systems were deposited when sea level was near its lowest position and sediment derived from deltas was transported into the deep basin via submarine canyons. During highstands in sea level, a thin layer of hemipelagic sediment was deposited on the fan surface. The Mississippi Fan serves as an exploration model for mud-dominated submarine fans and has four prospective reservoir facies: channel sands with linear trends, unchannelized sands beyond the downdip terminus of the channel (possible lobes), potentially sand-prone levees immediately adjacent to initial channels deposited in some sequences, and limited parts of mass transport complexes.

@article{doi1013060c9b2321171011d78645000102c1865d,
    author = "Weimer, Paul",
    title = "Sequence Stratigraphy, Facies Geometries, and Depositional History of the Mississippi Fan, Gulf of Mexico",
    year = "1990",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT The Mississippi Fan is a large, mud-dominated submarine fan over 4 km thick that was deposited in the deep Gulf of Mexico during the late Pliocene and Pleistocene. Analysis of 19000 km of multifold seismic data across the fan defined 17 seismic sequences, each characterized by a series of channel, levee, and associated overbank deposits, along with other mass transport deposits. At the base of nine sequences are a series of seismic facies consisting of mounded, hummocky, chaotic, and subparallel reflections, which constitute 10–20\% of the sediments in the sequence. These facies are externally mounded in cross section and occur in two general regions of the fan. In the upper and middle fan, they occur below channels and are elongated in shape, mimicking the channel’s distribution. In the middle to lower fan, they have a fan-shaped distribution, increasing in width downfan. These facies are interpreted to have formed as disorganized slides, debris flows, and turbidites, and are informally called mass transport complexes. Overlying this basal interval and characteristic of all sequences are well-developed channel-levee systems, which constitute 80–90\% of the fan’s sediments. Channels consist of high-amplitude, subparallel reflections. Levee sediments have subparallel reflections that have moderate to high amplitudes at the base changing upward to low amplitude. The vertical change in amplitude may reflect a decrease in the grain size and bed thickness of the levee sediments. Overbank sediments consist of interbedded subparallel to hummocky and mounded reflections, suggesting both turbidites derived from the channel, as well as slides and debris flows derived from the slope. Pliocene–Pleistocene eustatic cycles are interpreted to have been the major factor controlling the timing and style of sedimentation in the fan. Mass transport complexes are interpreted to have formed during a lowering of sea level, and reflect sediments derived from retrogressive slumping during the formation of submarine canyons in the upper slope and outer shelf. Channel-levee systems were deposited when sea level was near its lowest position and sediment derived from deltas was transported into the deep basin via submarine canyons. During highstands in sea level, a thin layer of hemipelagic sediment was deposited on the fan surface. The Mississippi Fan serves as an exploration model for mud-dominated submarine fans and has four prospective reservoir facies: channel sands with linear trends, unchannelized sands beyond the downdip terminus of the channel (possible lobes), potentially sand-prone levees immediately adjacent to initial channels deposited in some sequences, and limited parts of mass transport complexes.",
    url = "https://doi.org/10.1306/0c9b2321-1710-11d7-8645000102c1865d",
    doi = "10.1306/0c9b2321-1710-11d7-8645000102c1865d",
    openalex = "W2121411543",
    references = "doi1010079781461251149, doi10100797814684827684, doi10100797894009324181, doi10100797894017280964, doi101007bf02431072, doi1010160025322771900533, doi1010160031018288900089, doi10113000167606198798728qcosdc20co2, doi10130603b59a5816d111d78645000102c1865d, doi101306703c9109170711d78645000102c1865d, doi101306703c910e170711d78645000102c1865d, doi10130694887889170411d78645000102c1865d, doi1040435695ms"
}

@misc{leipzig1990the32,
    author = "Leipzig, M. R",
    title = "The stratigraphy, electrofacies and depositional environments of the Reklaw Formation of Goliad and adjacent counties, south Texas",
    year = "1990",
    howpublished = "American Association of Petroleum Geologists, v. 215, no. 1, p. 76-84",
    note = "talkorigins\_source = {true}; raw\_reference = {Leipzig, M. R., 1990, The stratigraphy, electrofacies and depositional environments of the Reklaw Formation of Goliad and adjacent counties, south Texas: American Association of Petroleum Geologists, v. 215, no. 1, p. 76-84.}"
}

@misc{leipzig1990the33,
    author = "Leipzig, M. R. and Jetelina, D",
    title = "The Gibbs Sand- A new Wilcox reservoir in south Texas. Geologic and engineering considerations",
    year = "1990",
    howpublished = "American Association of Petroleum Geologists; In Prep",
    note = "talkorigins\_source = {true}; raw\_reference = {Leipzig, M. R., and Jetelina, D., 1990, The Gibbs Sand- A new Wilcox reservoir in south Texas. Geologic and engineering considerations: American Association of Petroleum Geologists; In Prep.}"
}

ABSTRACT High‐resolution seismic boomer profiles, with a vertical resolution of less than 1 m, together with piston cores and previous side‐scan sonar data, are used to describe late Quaternary sedimentation on the Var deep‐sea fan. Chronological control is provided by foram biostratigraphy and radiocarbon dating in cores, and is extended over the fan by seismic correlation. Regional erosional events correspond to the oxygen isotopic stage 2 and 6 glacial maxima. Cores and seismic data define a widespread surface sand layer that is correlated with prodelta failure in 1979 and subsequent submarine cable breaks. Numerical modelling constrains the character of this 1979 turbidity current. It originated from a relatively small slide on the upper prodelta that put sufficient material in suspension to form an accelerating turbidity current which eroded sand from the Var Canyon. The turbidity current was only 30 m thick on the Upper Valley, but experienced significant flow expansion in the Middle Valley to thicknesses of more than 120 m, where it spilled over the eastern Var Sedimentary Ridge at a velocity of about 2·5 m s −1. Other Holocene turbidity currents (with a recurrence interval of 1000 years) were somewhat muddier and thicker, but also deposited sand on the levees of the Middle Valley, and are inferred to have had a similar slide‐related origin. Late Pleistocene turbidity currents deposited thick mud beds on the Var Sedimentary Ridge. The presence of sediment waves and the mean cross‐flow slope inferred from levee asymmetry indicates that some of these flows were many hundreds of metres thick and flowed at velocities of about 0·35 m s −1. This contrast with Holocene turbidites suggests that a slide origin is unlikely. Estimated times for deposition of thick mud beds on the levees are many days to weeks. The Late Pleistocene flows may therefore result from hyperpycnal flow of glacial outwash in the Var River. The variation in the Late Pleistocene to Holocene turbidite sedimentation is controlled more by variations in sediment supply than by sea‐level change.

@article{doi101111j136530911993tb01350x,
    author = "Piper, David J. W. and Savoye, Bruno",
    title = "Processes of late Quaternary turbidity current flow and deposition on the Var deep‐sea fan, north‐west Mediterranean Sea",
    year = "1993",
    journal = "Sedimentology",
    abstract = "ABSTRACT High‐resolution seismic boomer profiles, with a vertical resolution of less than 1 m, together with piston cores and previous side‐scan sonar data, are used to describe late Quaternary sedimentation on the Var deep‐sea fan. Chronological control is provided by foram biostratigraphy and radiocarbon dating in cores, and is extended over the fan by seismic correlation. Regional erosional events correspond to the oxygen isotopic stage 2 and 6 glacial maxima. Cores and seismic data define a widespread surface sand layer that is correlated with prodelta failure in 1979 and subsequent submarine cable breaks. Numerical modelling constrains the character of this 1979 turbidity current. It originated from a relatively small slide on the upper prodelta that put sufficient material in suspension to form an accelerating turbidity current which eroded sand from the Var Canyon. The turbidity current was only 30 m thick on the Upper Valley, but experienced significant flow expansion in the Middle Valley to thicknesses of more than 120 m, where it spilled over the eastern Var Sedimentary Ridge at a velocity of about 2·5 m s −1. Other Holocene turbidity currents (with a recurrence interval of 1000 years) were somewhat muddier and thicker, but also deposited sand on the levees of the Middle Valley, and are inferred to have had a similar slide‐related origin. Late Pleistocene turbidity currents deposited thick mud beds on the Var Sedimentary Ridge. The presence of sediment waves and the mean cross‐flow slope inferred from levee asymmetry indicates that some of these flows were many hundreds of metres thick and flowed at velocities of about 0·35 m s −1. This contrast with Holocene turbidites suggests that a slide origin is unlikely. Estimated times for deposition of thick mud beds on the levees are many days to weeks. The Late Pleistocene flows may therefore result from hyperpycnal flow of glacial outwash in the Var River. The variation in the Late Pleistocene to Holocene turbidite sedimentation is controlled more by variations in sediment supply than by sea‐level change.",
    url = "https://doi.org/10.1111/j.1365-3091.1993.tb01350.x",
    doi = "10.1111/j.1365-3091.1993.tb01350.x",
    openalex = "W2073452764",
    references = "doi101007bf02431072, doi101029jc074i018p04544"
}

ABSTRACT Sandy turbidite sedimentation on the Mississippi Fan, initiated during the falling and maximum relative lowstand stages of sea level during the last glacio-eustatic cycle, was significant well into the mid to late sea level rise until the Holocene, 12,000–11,000 yr B.P. or slightly thereafter. Several factors suggest this late continuation of sandy turbidite sedimentation: (1) landward extension of the Mississippi Canyon into the mid-shelf water depths as sea level rose, (2) a major increase in glacial meltwater discharge and sediment loads (pebble to clay size) delivered directly to the head of the canyon by the Mississippi River during the rising sea level, (3) probable persistent interception of longshore drift by the canyon as it eroded landward, (4) steep gradients at the head of the canyon that favored slumping of depocenters and formation of turbidity currents, and (5) absence of expected coarse-grained lithologies and deltaic stratal patterns within the canyon, indicating sediment bypass through the canyon into deep water. The late sand-prone turbidite sedimentation inferred herein for the Mississippi Fan is compatible with the occurrence of sandy turbidites in the middle Amazon Fan subsequent to 13,285 ±650 yr B.P. and significant deposition of turbidites and clastics until the Holocene elsewhere in the deep ocean. Sand-prone turbidite sedimentation into the middle/late rise of sea level is in contrast to the common perception of sequence-stratigraphic models. This perception assumes that turbidite and fan sedimentation occurs mainly during falling, maximum lowstand, and early rise of sea level. Late continuation of significant sandy turbidite sedimentation will impact concepts of subsurface stratigraphic calibration, inferences of depositional systems, and reservoir predictions.

@article{doi101306bdff8e16171811d78645000102c1865d,
    author = "Kolla, V. and Perlmutter, Martin A.",
    title = "Timing of Turbidite Sedimentation on the Mississippi Fan",
    year = "1993",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT Sandy turbidite sedimentation on the Mississippi Fan, initiated during the falling and maximum relative lowstand stages of sea level during the last glacio-eustatic cycle, was significant well into the mid to late sea level rise until the Holocene, 12,000–11,000 yr B.P. or slightly thereafter. Several factors suggest this late continuation of sandy turbidite sedimentation: (1) landward extension of the Mississippi Canyon into the mid-shelf water depths as sea level rose, (2) a major increase in glacial meltwater discharge and sediment loads (pebble to clay size) delivered directly to the head of the canyon by the Mississippi River during the rising sea level, (3) probable persistent interception of longshore drift by the canyon as it eroded landward, (4) steep gradients at the head of the canyon that favored slumping of depocenters and formation of turbidity currents, and (5) absence of expected coarse-grained lithologies and deltaic stratal patterns within the canyon, indicating sediment bypass through the canyon into deep water. The late sand-prone turbidite sedimentation inferred herein for the Mississippi Fan is compatible with the occurrence of sandy turbidites in the middle Amazon Fan subsequent to 13,285 ±650 yr B.P. and significant deposition of turbidites and clastics until the Holocene elsewhere in the deep ocean. Sand-prone turbidite sedimentation into the middle/late rise of sea level is in contrast to the common perception of sequence-stratigraphic models. This perception assumes that turbidite and fan sedimentation occurs mainly during falling, maximum lowstand, and early rise of sea level. Late continuation of significant sandy turbidite sedimentation will impact concepts of subsurface stratigraphic calibration, inferences of depositional systems, and reservoir predictions.",
    url = "https://doi.org/10.1306/bdff8e16-1718-11d7-8645000102c1865d",
    doi = "10.1306/bdff8e16-1718-11d7-8645000102c1865d",
    openalex = "W2127029893",
    references = "doi101038342637a0, doi101111j136530911983tb00702x, doi101126science24148691043, doi1011300091761319890170926rosstm23co2, doi1013060c9b2321171011d78645000102c1865d, doi10130694887889170411d78645000102c1865d, doi101306bc743d7f16be11d78645000102c1865d, doi102110pec88010125, doi102307211375, doi1040435695ms, normark1978fan"
}

ABSTRACT Depositional systems in deep-water basin margins can be classified on the basis of grain size and feeder system into 12 classes: mud-rich, mud/sand-rich, sand-rich, and gravel-rich “point-source submarine fans;” mud-rich, mud/sand-rich, sand-rich, and gravel-rich “multiple-source submarine ramps;” and mud-rich, mud/sand-rich, sand-rich, and gravel-rich “linear-source slope aprons.” The size and stability of channels and the organization of the depositional sequences decreases toward a linear source as does the length:width ratio of the system. As grain size increases, so does slope gradient, impersistence of channel systems, and tendency for channels to migrate. As grain size diminishes, there is an increase in the size of the source area, the size of the depositional system, the downcurrent length, the persistence and size of flows, fan channels, channel-levee systems, and in the tendency to meander and for major slumps and sheet sands to reach the lower fan and basin plain. The exact positioning of any one depositional system within the scheme cannot always be precise, and the position may be altered by changes in tectonics, climate, supply, and sea level. However, the models derived from each system are sufficiently different to significantly affect the nature of petroleum prospectivity and reservoir pattern. Understanding and recognizing this variability is crucial to all elements of the exploration-production chain. In exploration, initial evaluations of prospectivity and commerciality rely on the accurate stratigraphic prediction of reservoir facies, architecture, and trapping styles. For field appraisal and reservoir development, a similar appreciation of variability aids reservoir description by capturing the distribution and architecture of reservoir and nonreservoir facies and their impact on reservoir delineation, reservoir behavior, and production performance.

@article{doi101306a25fe3bf171b11d78645000102c1865d,
    author = "Reading, Harold G. and Richards, Marcus",
    title = "Turbidite Systems in Deep-Water Basin Margins Classified by Grain Size and Feeder System",
    year = "1994",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT Depositional systems in deep-water basin margins can be classified on the basis of grain size and feeder system into 12 classes: mud-rich, mud/sand-rich, sand-rich, and gravel-rich “point-source submarine fans;” mud-rich, mud/sand-rich, sand-rich, and gravel-rich “multiple-source submarine ramps;” and mud-rich, mud/sand-rich, sand-rich, and gravel-rich “linear-source slope aprons.” The size and stability of channels and the organization of the depositional sequences decreases toward a linear source as does the length:width ratio of the system. As grain size increases, so does slope gradient, impersistence of channel systems, and tendency for channels to migrate. As grain size diminishes, there is an increase in the size of the source area, the size of the depositional system, the downcurrent length, the persistence and size of flows, fan channels, channel-levee systems, and in the tendency to meander and for major slumps and sheet sands to reach the lower fan and basin plain. The exact positioning of any one depositional system within the scheme cannot always be precise, and the position may be altered by changes in tectonics, climate, supply, and sea level. However, the models derived from each system are sufficiently different to significantly affect the nature of petroleum prospectivity and reservoir pattern. Understanding and recognizing this variability is crucial to all elements of the exploration-production chain. In exploration, initial evaluations of prospectivity and commerciality rely on the accurate stratigraphic prediction of reservoir facies, architecture, and trapping styles. For field appraisal and reservoir development, a similar appreciation of variability aids reservoir description by capturing the distribution and architecture of reservoir and nonreservoir facies and their impact on reservoir delineation, reservoir behavior, and production performance.",
    url = "https://doi.org/10.1306/a25fe3bf-171b-11d7-8645000102c1865d",
    doi = "10.1306/a25fe3bf-171b-11d7-8645000102c1865d",
    openalex = "W2112508324",
    references = "doi1010160012825288900645, doi101111j136530911983tb00702x, doi101111j136530911993tb01347x, doi10113000167606198394459ftaspi20co2, doi10130603b5b6aa16d111d78645000102c1865d, doi1013060c9b2321171011d78645000102c1865d, doi1013062f9182e316ce11d78645000102c1865d, doi1013065d25cc7916c111d78645000102c1865d, doi101306703c9109170711d78645000102c1865d, doi101306819a41a216c511d78645000102c1865d, doi101306ad4619e916f711d78645000102c1865d, doi101306ad462b3716f711d78645000102c1865d, doi101306bdff8e16171811d78645000102c1865d, normark1978fan, openalexw425049407"
}

ABSTRACT Seismic facies in Gulf of Mexico intraslope basins reflect the interplay of a variety of deep-water depositional processes and the evolution of accommodation space on the slope. This interplay of processes results in a transition from an early, sand-prone ponded basin-fill succession (ponded facies assemblage) to a later shale-prone, slope-bypass succession (bypass facies assemblage). Convergent-baselapping facies in combination with localized chaotic and draping facies dominate the ponded facies assemblage. Stratigraphic relationships among these three units illustrate how fill-and-spill depositional processes occur within ponded-basin accommodation space. Convergent-thinning facies with widespread chaotic and draping facies dominate the bypass facies assemblage. These units represent filling of different types of slope accommodation space. The transition from ponded to bypass facies assemblages can be sharp or gradational over hundreds of meters. Transitions occured across the central Gulf of Mexico during the late Pliocene between 2.0 and 1.8 Ma, and in the early Pleistocene between 1.2 and 1.0 Ma. Nearly synchronous transitions throughout basins in the upper to middle slope suggest that increased sediment supply, resulting from a second-order sea level fall, and capture of large drainage areas by the Mississippi River during the Pleistocene are the primary controls on development of this large-scale stratigraphic architecture.

@article{doi1013061d9bc5d9172d11d78645000102c1865d,
    author = "Prather, Bradford E. and Booth, J. R. and Steffens, G. S. and Craig, P. A.",
    title = "Classification, Lithologic Calibration, and Stratigraphic Succession of Seismic Facies of Intraslope Basins, Deep-Water Gulf of Mexico",
    year = "1998",
    journal = "AAPG Bulletin",
    abstract = "ABSTRACT Seismic facies in Gulf of Mexico intraslope basins reflect the interplay of a variety of deep-water depositional processes and the evolution of accommodation space on the slope. This interplay of processes results in a transition from an early, sand-prone ponded basin-fill succession (ponded facies assemblage) to a later shale-prone, slope-bypass succession (bypass facies assemblage). Convergent-baselapping facies in combination with localized chaotic and draping facies dominate the ponded facies assemblage. Stratigraphic relationships among these three units illustrate how fill-and-spill depositional processes occur within ponded-basin accommodation space. Convergent-thinning facies with widespread chaotic and draping facies dominate the bypass facies assemblage. These units represent filling of different types of slope accommodation space. The transition from ponded to bypass facies assemblages can be sharp or gradational over hundreds of meters. Transitions occured across the central Gulf of Mexico during the late Pliocene between 2.0 and 1.8 Ma, and in the early Pleistocene between 1.2 and 1.0 Ma. Nearly synchronous transitions throughout basins in the upper to middle slope suggest that increased sediment supply, resulting from a second-order sea level fall, and capture of large drainage areas by the Mississippi River during the Pleistocene are the primary controls on development of this large-scale stratigraphic architecture.",
    url = "https://doi.org/10.1306/1d9bc5d9-172d-11d7-8645000102c1865d",
    doi = "10.1306/1d9bc5d9-172d-11d7-8645000102c1865d",
    openalex = "W1951460972",
    references = "crossref1978gulf, crossref1995cenozoic, doi10100797814684827687, doi1010160025322771900533, doi10108000206817809471524, doi101111j136530911983tb00702x, doi101126science23547931156, doi1011300091761319940220511sranmf23co2, doi101130dnaggnaa97, doi10130603b59a5816d111d78645000102c1865d, doi1013060c9b2321171011d78645000102c1865d, doi101306ad461b9216f711d78645000102c1865d, doi101306bdff8e16171811d78645000102c1865d, doi101306m65604c6, doi102110pec83060121"
}

Abstract A Geographic Information System (GIS) database incorporating information from 241 publications, theses, and dissertations; well logs and paleontologic reports; and interpreted University of Texas Institute for Geophysics (UTIG) deep-basin seismic lines was used to map and interpret 18 basinwide genetic stratigraphic sequences that form the Gulf of Mexico basin Cenozoic fill. Eight principal extrabasinal fluvial axes provided the bulk of the sediment infill in the basin. First-order temporal and spatial use of these axes reflects four continent-scale phases of crustal uplift. Abundant sediment supply has prograded the northern and northwestern basin margin 150 to 180 mi (240 to 290 km) from its inherited Cretaceous position. Margin outbuilding has been locally and briefly interrupted by hypersubsidence due to salt withdrawal and mass wasting. Three depositional systems tracts characterize Cenozoic genetic sequences: (1) fluvial -> delta -> delta-fed apron, (2) coastal plain -> shore zone -> shelf -> shelf-fed apron, and (3) delta flank -> submarine fan. One or more examples of the fluvial -> delta -> delta-fed apron systems tract occur in each of the major genetic sequences. Immense volumes of sand have bypassed the shelf margin to be deposited in slope and base-of-slope systems, primarily within fluvial -> delta -> delta-fed apron system tracts, during all major Paleogene and Neogene depositional episodes. Deposition and preservation of volumetrically significant coastal plain -> shore zone -> shelf -> shelf-fed apron tracts is typical of Paleogene through Miocene depositional episodes only. Fan system origin was commonly associated with major continental margin failures, but large submarine canyons occur mainly in Pleistocene sequences. Thick, potential reservoir sand bodies occur in offlapping delta-fed slope and subjacent basin floor aprons, in autochthonous slope aprons and related infills of slide scars and canyon cuts, and in submarine fans.

@article{doi1013068626c37f173b11d78645000102c1865d,
    author = "Galloway, William E. and Ganey-Curry, Patricia and Li, Xiang and Buffler, Richard T.",
    title = "Cenozoic Depositional History of the Gulf of Mexico Basin",
    year = "2000",
    journal = "AAPG Bulletin",
    abstract = "Abstract A Geographic Information System (GIS) database incorporating information from 241 publications, theses, and dissertations; well logs and paleontologic reports; and interpreted University of Texas Institute for Geophysics (UTIG) deep-basin seismic lines was used to map and interpret 18 basinwide genetic stratigraphic sequences that form the Gulf of Mexico basin Cenozoic fill. Eight principal extrabasinal fluvial axes provided the bulk of the sediment infill in the basin. First-order temporal and spatial use of these axes reflects four continent-scale phases of crustal uplift. Abundant sediment supply has prograded the northern and northwestern basin margin 150 to 180 mi (240 to 290 km) from its inherited Cretaceous position. Margin outbuilding has been locally and briefly interrupted by hypersubsidence due to salt withdrawal and mass wasting. Three depositional systems tracts characterize Cenozoic genetic sequences: (1) fluvial -\> delta -\> delta-fed apron, (2) coastal plain -\> shore zone -\> shelf -\> shelf-fed apron, and (3) delta flank -\> submarine fan. One or more examples of the fluvial -\> delta -\> delta-fed apron systems tract occur in each of the major genetic sequences. Immense volumes of sand have bypassed the shelf margin to be deposited in slope and base-of-slope systems, primarily within fluvial -\> delta -\> delta-fed apron system tracts, during all major Paleogene and Neogene depositional episodes. Deposition and preservation of volumetrically significant coastal plain -\> shore zone -\> shelf -\> shelf-fed apron tracts is typical of Paleogene through Miocene depositional episodes only. Fan system origin was commonly associated with major continental margin failures, but large submarine canyons occur mainly in Pleistocene sequences. Thick, potential reservoir sand bodies occur in offlapping delta-fed slope and subjacent basin floor aprons, in autochthonous slope aprons and related infills of slide scars and canyon cuts, and in submarine fans.",
    url = "https://doi.org/10.1306/8626c37f-173b-11d7-8645000102c1865d",
    doi = "10.1306/8626c37f-173b-11d7-8645000102c1865d",
    openalex = "W2105082865",
    references = "caughey1981deltaic, doi10100797814684827687, doi1010079783642610189, doi1010160025322771900533, doi101086629710, doi1011300091761319930210483nagmhf23co2, doi101130dnaggnaj245, doi1013060c9b2321171011d78645000102c1865d, doi1013061d9bc5bb172d11d78645000102c1865d, doi1013061d9bc5d9172d11d78645000102c1865d, doi101306703c9afa170711d78645000102c1865d, doi101306bdff8876171811d78645000102c1865d, doi101306bdff8f88171811d78645000102c1865d, doi102110pec95040129, doi105724gcs84050109, openalexw1599441881"
}

Abstract Most submarine fans are supplied with both sand and mud, but these become segregated during transport, typically with the sand becoming concentrated in channels and channel-termination lobes. New data from high-resolution seismic reflection surveys and Deep Sea Drilling Project (DSDP)/Ocean Drilling Program (ODP) wells from a variety of fans allow a synthesis of the architecture of those submarine fans that have important sand deposits. By analyzing architectural elements, we can better understand issues important for petroleum geology, such as the reservoir properties of the sand bodies and their lateral continuity and vertical connectivity. Our analysis of fan architecture is based principally on the Amazon and Hueneme fans, generally perceived to be classic examples of muddy and sandy systems, respectively. We recognize depositional elements, for example, channel deposits, levees, and lobes, from seismic reflection data and document sediment character in different elements from DSDP/ODP drill cores. We show the utility for petroleum geology of evaluating sandy and muddy elements rather than characterizing entire fans as sand rich or mud rich. We suggest that fan classification should include evaluation of source-sediment volumes and grain size, as well as the probable processes of turbidity-current initiation, because these factors control the character of fan elements and their response to changes in sea level, sediment supply, and autocyclic changes in channel pattern. Basin morphology, controlled by tectonics, influences overall geometry, as well as the balance between aggradation and progradation.

@article{doi1013068626cacd173b11d78645000102c1865d,
    author = "Piper, David J. W. and Normark, William R.",
    title = "Sandy Fans-From Amazon to Hueneme and Beyond",
    year = "2001",
    journal = "AAPG Bulletin",
    abstract = "Abstract Most submarine fans are supplied with both sand and mud, but these become segregated during transport, typically with the sand becoming concentrated in channels and channel-termination lobes. New data from high-resolution seismic reflection surveys and Deep Sea Drilling Project (DSDP)/Ocean Drilling Program (ODP) wells from a variety of fans allow a synthesis of the architecture of those submarine fans that have important sand deposits. By analyzing architectural elements, we can better understand issues important for petroleum geology, such as the reservoir properties of the sand bodies and their lateral continuity and vertical connectivity. Our analysis of fan architecture is based principally on the Amazon and Hueneme fans, generally perceived to be classic examples of muddy and sandy systems, respectively. We recognize depositional elements, for example, channel deposits, levees, and lobes, from seismic reflection data and document sediment character in different elements from DSDP/ODP drill cores. We show the utility for petroleum geology of evaluating sandy and muddy elements rather than characterizing entire fans as sand rich or mud rich. We suggest that fan classification should include evaluation of source-sediment volumes and grain size, as well as the probable processes of turbidity-current initiation, because these factors control the character of fan elements and their response to changes in sea level, sediment supply, and autocyclic changes in channel pattern. Basin morphology, controlled by tectonics, influences overall geometry, as well as the balance between aggradation and progradation.",
    url = "https://doi.org/10.1306/8626cacd-173b-11d7-8645000102c1865d",
    doi = "10.1306/8626cacd-173b-11d7-8645000102c1865d",
    openalex = "W2082942560",
    references = "doi1010160012825288900645, doi101130001676061969801859dfpap20co2"
}

Analyses of 3-D seismic data in predominantly basin-floor settings offshore Indonesia, Nigeria, and the Gulf of Mexico, reveal the extensive presence of gravity-flow depositional elements. Five key elements were observed: (1) turbidity-flow leveed channels, (2) channel-overbank sediment waves and levees, (3) frontal splays or distributary-channel complexes, (4) crevasse-splay complexes, and (5) debris-flow channels, lobes, and sheets. Each depositional element displays a unique morphology and seismic expression. The reservoir architecture of each of these depositional elements is a function of the interaction between sedimentary process, sea-floor morphology, and sediment grain-size distribution. (1) Turbidity-flow leveed-channel widths range from greater than 3 km to less than 200 m. Sinuosity ranges from moderate to high, and channel meanders in most instances migrate down-system. The high-amplitude reflection character that commonly characterizes these features suggests the presence of sand within the channels. In some instances, high-sinuosity channels are associated with (2) channel-overbank sediment-wave development in proximal overbank levee settings, especially in association with outer channel bends. These sediment waves reach heights of 20 m and spacings of 2-3 km. The crests of these sediment waves are oriented normal to the inferred transport direction of turbidity flows, and the waves have migrated in an up-flow direction. Channel-margin levee thickness decreases systematically down-system. Where levee thickness can no longer be resolved seismically, high-sinuosity channels feed (3) frontal splays or low-sinuosity, distributary-channel complexes. Low-sinuosity distributary-channel complexes are expressed as lobate sheets up to 5-10 km wide and tens of kilometers long that extend to the distal edges of these systems. They likely comprise sheet-like sandstone units consisting of shallow channelized and associated sand-rich overbank deposits. Also observed are (4) crevasse-splay deposits, which form as a result of the breaching of levees, commonly at channel bends. Similar to frontal splays, but smaller in size, these deposits commonly are characterized by sheet-like turbidites. (5) Debris-flow deposits comprise low-sinuosity channel fills, narrow elongate lobes, and sheets and are characterized seismically by contorted, chaotic, low-amplitude reflection patterns. These deposits commonly overlie striated or grooved pavements that can be up to tens of kilometers long, 15 m deep, and 25 m wide. Where flows are unconfined, striation patterns suggest that divergent flow is common. Debris-flow deposits extend as far basinward as turbidites, and individual debris-flow units can reach 80 m in thickness and commonly are marked by steep edges. Transparent to chaotic seismic reflection character suggest that these deposits are mud-rich. Stratigraphically, deep-water basin-floor successions commonly are characterized by mass-transport deposits at the base, overlain by turbidite frontal-splay deposits and subsequently by leveed-channel deposits. Capping this succession is another mass-transport unit ultimately overlain and draped by condensed-section deposits. This succession can be related to a cycle of relative sea-level change and associated events at the corresponding shelf edge. Commonly, deposition of a deep-water sequence is initiated with the onset of relative sea-level fall and ends with subsequent rapid relative sea-level rise.

@article{doi101306111302730367,
    author = "Posamentier, Henry W. and Kolla, V.",
    title = "Seismic Geomorphology and Stratigraphy of Depositional Elements in Deep-Water Settings",
    year = "2003",
    journal = "Journal of Sedimentary Research",
    abstract = "Analyses of 3-D seismic data in predominantly basin-floor settings offshore Indonesia, Nigeria, and the Gulf of Mexico, reveal the extensive presence of gravity-flow depositional elements. Five key elements were observed: (1) turbidity-flow leveed channels, (2) channel-overbank sediment waves and levees, (3) frontal splays or distributary-channel complexes, (4) crevasse-splay complexes, and (5) debris-flow channels, lobes, and sheets. Each depositional element displays a unique morphology and seismic expression. The reservoir architecture of each of these depositional elements is a function of the interaction between sedimentary process, sea-floor morphology, and sediment grain-size distribution. (1) Turbidity-flow leveed-channel widths range from greater than 3 km to less than 200 m. Sinuosity ranges from moderate to high, and channel meanders in most instances migrate down-system. The high-amplitude reflection character that commonly characterizes these features suggests the presence of sand within the channels. In some instances, high-sinuosity channels are associated with (2) channel-overbank sediment-wave development in proximal overbank levee settings, especially in association with outer channel bends. These sediment waves reach heights of 20 m and spacings of 2-3 km. The crests of these sediment waves are oriented normal to the inferred transport direction of turbidity flows, and the waves have migrated in an up-flow direction. Channel-margin levee thickness decreases systematically down-system. Where levee thickness can no longer be resolved seismically, high-sinuosity channels feed (3) frontal splays or low-sinuosity, distributary-channel complexes. Low-sinuosity distributary-channel complexes are expressed as lobate sheets up to 5-10 km wide and tens of kilometers long that extend to the distal edges of these systems. They likely comprise sheet-like sandstone units consisting of shallow channelized and associated sand-rich overbank deposits. Also observed are (4) crevasse-splay deposits, which form as a result of the breaching of levees, commonly at channel bends. Similar to frontal splays, but smaller in size, these deposits commonly are characterized by sheet-like turbidites. (5) Debris-flow deposits comprise low-sinuosity channel fills, narrow elongate lobes, and sheets and are characterized seismically by contorted, chaotic, low-amplitude reflection patterns. These deposits commonly overlie striated or grooved pavements that can be up to tens of kilometers long, 15 m deep, and 25 m wide. Where flows are unconfined, striation patterns suggest that divergent flow is common. Debris-flow deposits extend as far basinward as turbidites, and individual debris-flow units can reach 80 m in thickness and commonly are marked by steep edges. Transparent to chaotic seismic reflection character suggest that these deposits are mud-rich. Stratigraphically, deep-water basin-floor successions commonly are characterized by mass-transport deposits at the base, overlain by turbidite frontal-splay deposits and subsequently by leveed-channel deposits. Capping this succession is another mass-transport unit ultimately overlain and draped by condensed-section deposits. This succession can be related to a cycle of relative sea-level change and associated events at the corresponding shelf edge. Commonly, deposition of a deep-water sequence is initiated with the onset of relative sea-level fall and ends with subsequent rapid relative sea-level rise.",
    url = "https://doi.org/10.1306/111302730367",
    doi = "10.1306/111302730367",
    openalex = "W1483157968",
    references = "doi101007978146848276818, doi10100797814684827684, doi101086629747, doi101086648221, doi101111j136530911983tb00702x, doi1013061d9bc5d9172d11d78645000102c1865d, doi1013062dc4091c0e4711d78643000102c1865d, doi1013062f9182e316ce11d78645000102c1865d, doi1013065d25cc7916c111d78645000102c1865d, doi101306a25fe3bf171b11d78645000102c1865d, doi101306m26490c5, doi102110csp9907, doi105724gcs00150782, nardin1979a, normark1978fan, openalexw1570283708, openalexw3120543430, openalexw362631153"
}

@article{covault2007highstand,
    author = "Covault, Jacob A. and Normark, William R. and Romans, Brian W. and Graham, Stephan A.",
    title = "Highstand fans in the California borderland: The overlooked deep-water depositional systems",
    year = "2007",
    journal = "Geology",
    url = "https://doi.org/10.1130/g23800a.1",
    doi = "10.1130/g23800a.1",
    number = "9",
    openalex = "W2084064600",
    pages = "783",
    volume = "35",
    references = "doi10100797814684827686, doi101016jquascirev200403006, doi101016s0025322702006771, doi10112111908210, doi101126science1059549, doi101130g225051, doi1013065d25c61516c111d78645000102c1865d, doi1013065d25cc7916c111d78645000102c1865d, doi101306bc743d7f16be11d78645000102c1865d, doi101306m26490c6"
}

Abstract The Mississippian Barnett Formation of the Fort Worth Basin is a classic shale-gas system in which the rock is the source, reservoir, and seal. Barnett strata were deposited in a deeper water foreland basin that had poor circulation with the open ocean. For most of the basin's history, bottom waters were euxinic, preserving organic matter and, thus, creating a rich source rock, along with abundant framboidal pyrite. The Barnett interval comprises a variety of facies but is dominated by fine-grained (clay- to silt-size) particles. Three general lithofacies are recognized on the basis of mineralogy, fabric, biota, and texture: (1) laminated siliceous mudstone; (2) laminated argillaceous lime mudstone (marl); and (3) skeletal, argillaceous lime packstone. Each facies contains abundant pyrite and phosphate (apatite), which are especially common at hardgrounds. Carbonate concretions, a product of early diagenesis, are also common. The entire Barnett biota is composed of debris transported to the basin from the shelf or upper oxygenated slope by hemipelagic mud plumes, dilute turbidites, and debris flows. Biogenic sediment was also sourced from the shallower, better oxygenated water column. Barnett deposition is estimated to have occurred over a 25-m.y. period, and despite the variations in sublithofacies, sedimentation style remained remarkably similar throughout this span of time.

@article{doi10130611020606059,
    author = "Loucks, Robert G. and Ruppel, Stephen C.",
    title = "Mississippian Barnett Shale: Lithofacies and depositional setting of a deep-water shale-gas succession in the Fort Worth Basin, Texas",
    year = "2007",
    journal = "AAPG Bulletin",
    abstract = "Abstract The Mississippian Barnett Formation of the Fort Worth Basin is a classic shale-gas system in which the rock is the source, reservoir, and seal. Barnett strata were deposited in a deeper water foreland basin that had poor circulation with the open ocean. For most of the basin's history, bottom waters were euxinic, preserving organic matter and, thus, creating a rich source rock, along with abundant framboidal pyrite. The Barnett interval comprises a variety of facies but is dominated by fine-grained (clay- to silt-size) particles. Three general lithofacies are recognized on the basis of mineralogy, fabric, biota, and texture: (1) laminated siliceous mudstone; (2) laminated argillaceous lime mudstone (marl); and (3) skeletal, argillaceous lime packstone. Each facies contains abundant pyrite and phosphate (apatite), which are especially common at hardgrounds. Carbonate concretions, a product of early diagenesis, are also common. The entire Barnett biota is composed of debris transported to the basin from the shelf or upper oxygenated slope by hemipelagic mud plumes, dilute turbidites, and debris flows. Biogenic sediment was also sourced from the shallower, better oxygenated water column. Barnett deposition is estimated to have occurred over a 25-m.y. period, and despite the variations in sublithofacies, sedimentation style remained remarkably similar throughout this span of time.",
    url = "https://doi.org/10.1306/11020606059",
    doi = "10.1306/11020606059",
    openalex = "W2166476646",
    references = "doi1010160016703796002098, doi101038142234b0, doi101046j13653091200100360x, doi1013065ceadd7616bb11d78645000102c1865d"
}

Abstract The concept of turbidite has evolved so much since its original definition by Kuenen and Migliorini in 1950 – i.e. the deposit of turbidity currents exemplified by the sandy flysch successions of the Northern Apennines – that it is now used to define a variety of deposits, some of which have little in common with sandy flysch formations in terms of facies, geometry and geological significance. The extension of the concept to other geodynamic settings and deposits of non‐siliciclastic composition is considered only briefly in the concluding sections. With the diffusion of the concept of turbidity current, in the 1950s and early 1960s, an entirely new branch of sedimentology came into being, concerned with the inventory of sedimentary structures, palaeocurrent measurements and bedding patterns. The most representative expression of this branch came from the ‘Dutch school’ of Philip H. Kuenen and his students. Between the late 1960s and the mid‐1970s, there was a new development: facies analysis, in terms of modern environments and depositional systems. This development led to the introduction and discussion of ‘fan models’ that became an increasingly thorny issue with the accumulation of data from modern deep‐marine settings. In particular, most researchers emphasized the importance of channel and lobe elements and their mutual relationships in space and time. These models may differ in terms of specific features, e.g. canyon‐fed versus delta‐fed ramp settings and terminology, but the basic distinction between channels (sediment pathways), lobes and basin plains (sheet‐like depositional features) was and still is widely retained – a model that simply refers to a system where a distributary channel passes downstream to a depositional zone, like in most fluvio‐deltaic systems. Great caution should, however, be exercised when comparing modern and ancient fans – a problem discussed at length in the Committee on Submarine Fans I convened by A.H. Bouma and held in Pittsburgh in 1982. Different data sets and geological contexts, scaling problems and terminology still cast doubt over how meaningful such a comparison may be. Despite the many problems encountered, the elemental approach provides an easy, essentially descriptive tool to significantly compare recent with ancient, recent with recent, and ancient with ancient systems. Beginning in the 1970s, process‐oriented facies analysis led to increasingly complex facies classification schemes, which showed substantial departures from the classic Bouma sequence and introduced many new concepts: proximal versus distal sedimentation, sediment bypass and flow efficiency, in addition to deflection, reflection and ponding of turbidity currents in confined basins. During the last two decades, there has been an increased interest in attempting to interpret the incredibly detailed submarine landscapes obtained through advances in marine geology, technology and high‐resolution three‐dimensional seismic data provided by the oil industry. Outcrop ‘analogues’ derived from orogenic belts are used commonly to improve the interpretation of seismic‐reflection facies, although their actual value may be questioned in many cases. Seismic–stratigraphic concepts are used routinely to describe and interpret turbidite systems of continental margin basins where cyclic sea‐level variations are thought to be essentially controlled by eustasy. These concepts are difficult to apply to flysch basins, where the tectonic control on the development of cycles of relative sea‐level variations appears to be dominant. In particular, the huge volumes of sediment involved in the infill of flysch basins imply amounts of uplift of the source areas and subsidence of the receiving basins that clearly outstrip those of divergent continental margins controlled by eustasy and thermal subsidence. Cycles of tectonic uplift and denudation (Davisian‐type cycles in the sense of Mutti et al., 1996) apparently play a major role here. Most recent attempts to understand turbidite deposition are related to the increased economic importance of turbidite sandbodies as hydrocarbon reservoirs in many offshore basins (e.g. Gulf of Mexico, West Africa, Brazil, the North Sea). The many problems inherent to this situation have been reviewed extensively in a workshop held in Parma in 2002; only some of these problems are reconsidered briefly in this paper. Sandy turbidite systems can be generated by the resedimentation of deltaic deposits through submarine slides or be derived directly from flood‐generated hyperpycnal flows; in the latter case, climatic variations must have played a fundamental role in controlling flood frequency and magnitude with time. Recognizing these two different types of system is not always easy and requires a good understanding of the geological context of the basin under consideration and particularly of the role of marginal fluvio‐deltaic systems from which turbidites are ultimately derived. Unfortunately, this kind of integrated analysis is still in its infancy. There are other types of turbidite deposits, such as the calcareous flysch of the Western Alps and the Northern Apennines, whose origin still remains a matter of debate in terms of sediment source and triggering mechanisms of large‐volume turbidity currents essentially loaded with fine‐grained biogenic sediment. Some authors have referred to these sediments either as ‘megaturbidites’ or ‘seismoturbidites’. The importance of tectonic control and geodynamic setting is stressed for turbidite systems of orogenic belt basins, which is justified both by historical reasons (turbidites were from their recognition included in the definition of flysch) and recent studies of thrust belts. The time is now ripe for reconsidering these sediments within a broader framework that takes into account the enormous quantity of data and concepts that have been developed in the last 50 years; this in itself raises a problem, and no small one: the accuracy and quality of data collected in the field and the training of young scientists. How many field geologists are being produced in these times of increasingly computerized geology; and how good are they?

@article{doi101111j13653091200801019x,
    author = "Mutti, Emiliano and Bernoulli, Daniel and Lucchi, Franco Ricci and Tinterri, Roberto",
    title = "Turbidites and turbidity currents from Alpine ‘flysch’ to the exploration of continental margins",
    year = "2008",
    journal = "Sedimentology",
    abstract = "Abstract The concept of turbidite has evolved so much since its original definition by Kuenen and Migliorini in 1950 – i.e. the deposit of turbidity currents exemplified by the sandy flysch successions of the Northern Apennines – that it is now used to define a variety of deposits, some of which have little in common with sandy flysch formations in terms of facies, geometry and geological significance. The extension of the concept to other geodynamic settings and deposits of non‐siliciclastic composition is considered only briefly in the concluding sections. With the diffusion of the concept of turbidity current, in the 1950s and early 1960s, an entirely new branch of sedimentology came into being, concerned with the inventory of sedimentary structures, palaeocurrent measurements and bedding patterns. The most representative expression of this branch came from the ‘Dutch school’ of Philip H. Kuenen and his students. Between the late 1960s and the mid‐1970s, there was a new development: facies analysis, in terms of modern environments and depositional systems. This development led to the introduction and discussion of ‘fan models’ that became an increasingly thorny issue with the accumulation of data from modern deep‐marine settings. In particular, most researchers emphasized the importance of channel and lobe elements and their mutual relationships in space and time. These models may differ in terms of specific features, e.g. canyon‐fed versus delta‐fed ramp settings and terminology, but the basic distinction between channels (sediment pathways), lobes and basin plains (sheet‐like depositional features) was and still is widely retained – a model that simply refers to a system where a distributary channel passes downstream to a depositional zone, like in most fluvio‐deltaic systems. Great caution should, however, be exercised when comparing modern and ancient fans – a problem discussed at length in the Committee on Submarine Fans I convened by A.H. Bouma and held in Pittsburgh in 1982. Different data sets and geological contexts, scaling problems and terminology still cast doubt over how meaningful such a comparison may be. Despite the many problems encountered, the elemental approach provides an easy, essentially descriptive tool to significantly compare recent with ancient, recent with recent, and ancient with ancient systems. Beginning in the 1970s, process‐oriented facies analysis led to increasingly complex facies classification schemes, which showed substantial departures from the classic Bouma sequence and introduced many new concepts: proximal versus distal sedimentation, sediment bypass and flow efficiency, in addition to deflection, reflection and ponding of turbidity currents in confined basins. During the last two decades, there has been an increased interest in attempting to interpret the incredibly detailed submarine landscapes obtained through advances in marine geology, technology and high‐resolution three‐dimensional seismic data provided by the oil industry. Outcrop ‘analogues’ derived from orogenic belts are used commonly to improve the interpretation of seismic‐reflection facies, although their actual value may be questioned in many cases. Seismic–stratigraphic concepts are used routinely to describe and interpret turbidite systems of continental margin basins where cyclic sea‐level variations are thought to be essentially controlled by eustasy. These concepts are difficult to apply to flysch basins, where the tectonic control on the development of cycles of relative sea‐level variations appears to be dominant. In particular, the huge volumes of sediment involved in the infill of flysch basins imply amounts of uplift of the source areas and subsidence of the receiving basins that clearly outstrip those of divergent continental margins controlled by eustasy and thermal subsidence. Cycles of tectonic uplift and denudation (Davisian‐type cycles in the sense of Mutti et al., 1996) apparently play a major role here. Most recent attempts to understand turbidite deposition are related to the increased economic importance of turbidite sandbodies as hydrocarbon reservoirs in many offshore basins (e.g. Gulf of Mexico, West Africa, Brazil, the North Sea). The many problems inherent to this situation have been reviewed extensively in a workshop held in Parma in 2002; only some of these problems are reconsidered briefly in this paper. Sandy turbidite systems can be generated by the resedimentation of deltaic deposits through submarine slides or be derived directly from flood‐generated hyperpycnal flows; in the latter case, climatic variations must have played a fundamental role in controlling flood frequency and magnitude with time. Recognizing these two different types of system is not always easy and requires a good understanding of the geological context of the basin under consideration and particularly of the role of marginal fluvio‐deltaic systems from which turbidites are ultimately derived. Unfortunately, this kind of integrated analysis is still in its infancy. There are other types of turbidite deposits, such as the calcareous flysch of the Western Alps and the Northern Apennines, whose origin still remains a matter of debate in terms of sediment source and triggering mechanisms of large‐volume turbidity currents essentially loaded with fine‐grained biogenic sediment. Some authors have referred to these sediments either as ‘megaturbidites’ or ‘seismoturbidites’. The importance of tectonic control and geodynamic setting is stressed for turbidite systems of orogenic belt basins, which is justified both by historical reasons (turbidites were from their recognition included in the definition of flysch) and recent studies of thrust belts. The time is now ripe for reconsidering these sediments within a broader framework that takes into account the enormous quantity of data and concepts that have been developed in the last 50 years; this in itself raises a problem, and no small one: the accuracy and quality of data collected in the field and the training of young scientists. How many field geologists are being produced in these times of increasingly computerized geology; and how good are they?",
    url = "https://doi.org/10.1111/j.1365-3091.2008.01019.x",
    doi = "10.1111/j.1365-3091.2008.01019.x",
    openalex = "W2126274779",
    references = "doi1010160012825286900012, doi1010160012825289900020, doi101016jmargeo200410001, doi101016jmarpetgeo200309001, doi101016s0070457108709543, doi10102995rg03287, doi101086629606, doi101086629747, doi101111j13653091200801016x, doi101130001676061959701089tifotp20co2, doi101306212f7f312b2411d78648000102c1865d, doi101306mth7510, doi102110pec88010039, doi102110pec88010109, doi105860choice295709, openalexw1570283708, openalexw3160761443"
}

@article{doi101130g310811,
    author = "Covault, Jacob A. and Graham, Stephan A.",
    title = "Submarine fans at all sea-level stands: Tectono-morphologic and climatic controls on terrigenous sediment delivery to the deep sea",
    year = "2010",
    journal = "Geology",
    url = "https://doi.org/10.1130/g31081.1",
    doi = "10.1130/g31081.1",
    openalex = "W2322744307",
    references = "covault2007highstand, doi101306bdff8e16171811d78645000102c1865d"
}

Abstract Diagenesis exerts a strong control on the quality and heterogeneity of most clastic reservoirs. Variations in the distribution of diagenetic alterations usually accentuate the variations in depositional porosity and permeability. Linking the types and distribution of diagenetic processes to the depositional facies and sequence-stratigraphic framework of clastic successions provides a powerful tool to predict the distribution of diagenetic alterations controlling quality and heterogeneity. The heterogeneity patterns of sandstone reservoirs, which determine the volumes, flow rates, and recovery of hydrocarbons, are controlled by geometry and internal structures of sand bodies, grain size, sorting, degree of bioturbation, provenance, and by the types, volumes, and distribution of diagenetic alterations. Variations in the pathways of diagenetic evolution are linked to (1) depositional facies, hence pore-water chemistry, depositional porosity and permeability, types and amounts of intrabasinal grains, and extent of bioturbation; (2) detrital sand composition; (3) rate of deposition (controlling residence time of sediments at specific near-surface, geochemical conditions); and (4) burial thermal history of the basin. The amounts and types of intrabasinal grains are also controlled by changes in the relative sea level and, therefore, can be predicted in the context of sequence stratigraphy, particularly in paralic and shallow marine environments. Changes in the relative sea level exert significant control on the types and extent of near-surface shallow burial diagenetic alterations, which in turn influence the pathways of burial diagenetic and reservoir quality evolution of clastic reservoirs. Carbonate cementation is more extensive in transgressive systems tract (TST) sandstones, particularly below parasequence boundaries, transgressive surface, and maximum flooding surface because of the abundance of carbonate bioclasts and organic matter, bioturbation, and prolonged residence time of the sediments at and immediately below the sea floor caused by low sedimentation rates, which also enhance the formation of glaucony. Eogenetic grain-coating berthierine, odinite, and smectite, formed mostly in TST and early highstand systems tract deltaic and estuarine sandstones, are transformed into ferrous chlorite during mesodiagenesis, helping preserve reservoir quality through the inhibition of quartz cementation. The infiltration of grain-coating smectitic clays is more extensive in braided than in meandering fluvial sandstones, forming flow barriers in braided amalgamated reservoirs, and may either help preserve porosity during burial because of quartz overgrowth inhibition or reduce it by enhancing intergranular pressure dissolution. Diagenetic modifications along sequence boundaries are characterized by considerable dissolution and kaolinization of feldspars, micas, and mud intraclasts under wet and warm climates, whereas a semiarid climate may lead to the formation of calcrete dolocrete cemented layers. Turbidite sandstones are typically cemented by carbonate along the contacts with interbedded mudrocks or carbonate mudstones and marls, as well as along layers of concentration of carbonate bioclasts and intraclasts. Commonly, hybrid carbonate turbidite arenites are pervasively cemented. Proximal, massive turbidites normally show only scattered spherical or ovoid carbonate concretions. Improved geologic models based on the connections among diagenesis, depositional facies, and sequence-stratigraphic surfaces and intervals may not only contribute to optimized production through the design of appropriate simulation models for improved or enhanced oil recovery strategies, as well as for CO2 geologic sequestration, but also support more effective hydrocarbon exploration through reservoir quality prediction.

@article{doi10130604211009178,
    author = "Morad, S. and Al‐Ramadan, Khalid and Ketzer, Marcelo and Ros, Luiz Fernando De",
    title = "The impact of diagenesis on the heterogeneity of sandstone reservoirs: A review of the role of depositional facies and sequence stratigraphy",
    year = "2010",
    journal = "AAPG Bulletin",
    abstract = "Abstract Diagenesis exerts a strong control on the quality and heterogeneity of most clastic reservoirs. Variations in the distribution of diagenetic alterations usually accentuate the variations in depositional porosity and permeability. Linking the types and distribution of diagenetic processes to the depositional facies and sequence-stratigraphic framework of clastic successions provides a powerful tool to predict the distribution of diagenetic alterations controlling quality and heterogeneity. The heterogeneity patterns of sandstone reservoirs, which determine the volumes, flow rates, and recovery of hydrocarbons, are controlled by geometry and internal structures of sand bodies, grain size, sorting, degree of bioturbation, provenance, and by the types, volumes, and distribution of diagenetic alterations. Variations in the pathways of diagenetic evolution are linked to (1) depositional facies, hence pore-water chemistry, depositional porosity and permeability, types and amounts of intrabasinal grains, and extent of bioturbation; (2) detrital sand composition; (3) rate of deposition (controlling residence time of sediments at specific near-surface, geochemical conditions); and (4) burial thermal history of the basin. The amounts and types of intrabasinal grains are also controlled by changes in the relative sea level and, therefore, can be predicted in the context of sequence stratigraphy, particularly in paralic and shallow marine environments. Changes in the relative sea level exert significant control on the types and extent of near-surface shallow burial diagenetic alterations, which in turn influence the pathways of burial diagenetic and reservoir quality evolution of clastic reservoirs. Carbonate cementation is more extensive in transgressive systems tract (TST) sandstones, particularly below parasequence boundaries, transgressive surface, and maximum flooding surface because of the abundance of carbonate bioclasts and organic matter, bioturbation, and prolonged residence time of the sediments at and immediately below the sea floor caused by low sedimentation rates, which also enhance the formation of glaucony. Eogenetic grain-coating berthierine, odinite, and smectite, formed mostly in TST and early highstand systems tract deltaic and estuarine sandstones, are transformed into ferrous chlorite during mesodiagenesis, helping preserve reservoir quality through the inhibition of quartz cementation. The infiltration of grain-coating smectitic clays is more extensive in braided than in meandering fluvial sandstones, forming flow barriers in braided amalgamated reservoirs, and may either help preserve porosity during burial because of quartz overgrowth inhibition or reduce it by enhancing intergranular pressure dissolution. Diagenetic modifications along sequence boundaries are characterized by considerable dissolution and kaolinization of feldspars, micas, and mud intraclasts under wet and warm climates, whereas a semiarid climate may lead to the formation of calcrete dolocrete cemented layers. Turbidite sandstones are typically cemented by carbonate along the contacts with interbedded mudrocks or carbonate mudstones and marls, as well as along layers of concentration of carbonate bioclasts and intraclasts. Commonly, hybrid carbonate turbidite arenites are pervasively cemented. Proximal, massive turbidites normally show only scattered spherical or ovoid carbonate concretions. Improved geologic models based on the connections among diagenesis, depositional facies, and sequence-stratigraphic surfaces and intervals may not only contribute to optimized production through the design of appropriate simulation models for improved or enhanced oil recovery strategies, as well as for CO2 geologic sequestration, but also support more effective hydrocarbon exploration through reservoir quality prediction.",
    url = "https://doi.org/10.1306/04211009178",
    doi = "10.1306/04211009178",
    openalex = "W2138821921",
    references = "crossref1996the, doi101007978940172809615, doi1010160037073888901340, doi101016jearscirev200902004, doi101016s0012825202001058, doi10113000167606198394222ponaps20co2, doi101306212f76bc2b2411d78648000102c1865d, doi1013062dc409160e4711d78643000102c1865d, doi10130661eedabc173e11d78645000102c1865d, doi101306d4267a692b2611d78648000102c1865d, doi1015159780691209401, doi102110csp9907, doi102110pec88010109, doi105860choice301532, doi105860choice342173, openalexw3044656254"
}

Abstract Flows with high suspended sediment concentrations are common in many sedimentary environments, and their flow properties may show a transitional behaviour between fully turbulent and quasi‐laminar plug flows. The characteristics of these transitional flows are known to be a function of both clay concentration and type, as well as the applied fluid stress, but so far the interaction of these transitional flows with a loose sediment bed has received little attention. Information on this type of interaction is essential for the recognition and prediction of sedimentary structures formed by cohesive transitional flows in, for example, fluvial, estuarine and deep‐marine deposits. This paper investigates the behaviour of rapidly decelerated to steady flows that contain a mixture of sand, silt and clay, and explores the effect of different clay (kaolin) concentrations on the dynamics of flow over a mobile bed, and the bedforms and stratification produced. Experiments were conducted in a recirculating slurry flume capable of transporting high clay concentrations. Ultrasonic Doppler velocity profiling was used to measure the flow velocity within these concentrated suspension flows. The development of current ripples under decelerated flows of differing kaolin concentration was documented and evolution of their height, wavelength and migration rate quantified. This work confirms past work over smooth, fixed beds which showed that, as clay concentration rises, a distinct sequence of flow types is generated: turbulent flow, turbulence‐enhanced transitional flow, lower transitional plug flow, upper transitional plug flow and a quasi‐laminar plug flow. Each of these flow types produces an initial flat bed upon rapid flow deceleration, followed by reworking of these deposits through the development of current ripples during the subsequent steady flow in turbulent flow, turbulence‐enhanced transitional flow and lower transitional plug flow. The initial flat beds are structureless, but have diagnostic textural properties, caused by differential settling of sand, silt and cohesive mud, which forms characteristic bipartite beds that initially consist of sand overlain by silt or clay. As clay concentration in the formative flow increases, ripples first increase in mean height and wavelength under turbulence‐enhanced transitional flow and lower transitional plug‐flow regimes, which is attributed to the additional turbulence generated under these flows that subsequently causes greater lee side erosion. As clay concentration increases further from a lower transitional plug flow, ripples cease to exist under the upper transitional plug flow and quasi‐laminar plug flow conditions investigated herein. This disappearance of ripples appears due to both turbulence suppression at higher clay concentrations, as well as the increasing shear strength of the bed sediment that becomes more difficult to erode as clay concentration increases. The stratification within the ripples formed after rapid deceleration of the transitional flows reflects the availability of sediment from the bipartite bed. The exact nature of the ripple cross‐stratification in these flows is a direct function of the duration of the formative flow and the texture of the initial flat bed, and ripples do not form in cohesive flows with a Reynolds number smaller than ca 12 000. Examples are given of how the unique properties of the current ripples and plane beds, developing below decelerated transitional flows, could aid in the interpretation of depositional processes in modern and ancient sediments. This interpretation includes a new model for hybrid beds that explains their formation in terms of a combination of vertical grain‐size segregation and longitudinal flow transformation.

@article{doi101111j13653091201101247x,
    author = "Baas, Jaco H. and Best, Jim and Peakall, Jeff",
    title = "Depositional processes, bedform development and hybrid bed formation in rapidly decelerated cohesive (mud–sand) sediment flows",
    year = "2011",
    journal = "Sedimentology",
    abstract = "Abstract Flows with high suspended sediment concentrations are common in many sedimentary environments, and their flow properties may show a transitional behaviour between fully turbulent and quasi‐laminar plug flows. The characteristics of these transitional flows are known to be a function of both clay concentration and type, as well as the applied fluid stress, but so far the interaction of these transitional flows with a loose sediment bed has received little attention. Information on this type of interaction is essential for the recognition and prediction of sedimentary structures formed by cohesive transitional flows in, for example, fluvial, estuarine and deep‐marine deposits. This paper investigates the behaviour of rapidly decelerated to steady flows that contain a mixture of sand, silt and clay, and explores the effect of different clay (kaolin) concentrations on the dynamics of flow over a mobile bed, and the bedforms and stratification produced. Experiments were conducted in a recirculating slurry flume capable of transporting high clay concentrations. Ultrasonic Doppler velocity profiling was used to measure the flow velocity within these concentrated suspension flows. The development of current ripples under decelerated flows of differing kaolin concentration was documented and evolution of their height, wavelength and migration rate quantified. This work confirms past work over smooth, fixed beds which showed that, as clay concentration rises, a distinct sequence of flow types is generated: turbulent flow, turbulence‐enhanced transitional flow, lower transitional plug flow, upper transitional plug flow and a quasi‐laminar plug flow. Each of these flow types produces an initial flat bed upon rapid flow deceleration, followed by reworking of these deposits through the development of current ripples during the subsequent steady flow in turbulent flow, turbulence‐enhanced transitional flow and lower transitional plug flow. The initial flat beds are structureless, but have diagnostic textural properties, caused by differential settling of sand, silt and cohesive mud, which forms characteristic bipartite beds that initially consist of sand overlain by silt or clay. As clay concentration in the formative flow increases, ripples first increase in mean height and wavelength under turbulence‐enhanced transitional flow and lower transitional plug‐flow regimes, which is attributed to the additional turbulence generated under these flows that subsequently causes greater lee side erosion. As clay concentration increases further from a lower transitional plug flow, ripples cease to exist under the upper transitional plug flow and quasi‐laminar plug flow conditions investigated herein. This disappearance of ripples appears due to both turbulence suppression at higher clay concentrations, as well as the increasing shear strength of the bed sediment that becomes more difficult to erode as clay concentration increases. The stratification within the ripples formed after rapid deceleration of the transitional flows reflects the availability of sediment from the bipartite bed. The exact nature of the ripple cross‐stratification in these flows is a direct function of the duration of the formative flow and the texture of the initial flat bed, and ripples do not form in cohesive flows with a Reynolds number smaller than ca 12 000. Examples are given of how the unique properties of the current ripples and plane beds, developing below decelerated transitional flows, could aid in the interpretation of depositional processes in modern and ancient sediments. This interpretation includes a new model for hybrid beds that explains their formation in terms of a combination of vertical grain‐size segregation and longitudinal flow transformation.",
    url = "https://doi.org/10.1111/j.1365-3091.2011.01247.x",
    doi = "10.1111/j.1365-3091.2011.01247.x",
    openalex = "W1527721266",
    references = "doi101007bf00301484, doi101016jmarpetgeo200902012, doi101016s0264817299000112"
}

Abstract Climbing‐ripple cross‐lamination is most commonly deposited by turbidity currents when suspended load fallout and bedload transport occur contemporaneously. The angle of ripple climb reflects the ratio of suspended load fallout and bedload sedimentation rates, allowing for the calculation of the flow properties and durations of turbidity currents. Three areas exhibiting thick (>50 m) sections of deep‐water climbing‐ripple cross‐lamination deposits are the focus of this study: (i) the Miocene upper Mount Messenger Formation in the Taranaki Basin, New Zealand; (ii) the Permian Skoorsteenberg Formation in the Tanqua depocentre of the Karoo Basin, South Africa; and (iii) the lower Pleistocene Magnolia Field in the Titan Basin, Gulf of Mexico. Facies distributions and local contextual information indicate that climbing‐ripple cross‐lamination in each area was deposited in an ‘off‐axis’ setting where flows were expanding due to loss of confinement or a decrease in slope gradient. The resultant reduction in flow thickness, Reynolds number, shear stress and capacity promoted suspension fallout and thus climbing‐ripple cross‐lamination formation. Climbing‐ripple cross‐lamination in the New Zealand study area was deposited both outside of and within channels at an inferred break in slope, where flows were decelerating and expanding. In the South Africa study area, climbing‐ripple cross‐lamination was deposited due to a loss of flow confinement. In the Magnolia study area, an abrupt decrease in gradient near a basin sill caused flow deceleration and climbing‐ripple cross‐lamination deposition in off‐axis settings. Sedimentation rate and accumulation time were calculated for 44 climbing‐ripple cross‐lamination sedimentation units from the three areas using TDURE, a mathematical model developed by Baas et al. (2000). For T c divisions and T bc beds averaging 26 cm and 37 cm thick, respectively, average climbing‐ripple cross‐lamination and whole bed sedimentation rates were 0·15 mm sec −1 and 0·26 mm sec −1 and average accumulation times were 27 min and 35 min, respectively. In some instances, distinct stratigraphic trends of sedimentation rate give insight into the evolution of the depositional environment. Climbing‐ripple cross‐lamination in the three study areas is developed in very fine‐grained to fine‐grained sand, suggesting a grain size dependence on turbidite climbing‐ripple cross‐lamination formation. Indeed, the calculated sedimentation rates correlate well with the rate of sedimentation due to hindered settling of very fine‐grained and fine‐grained sand–water suspensions at concentrations of up to 20% and 2·5%, respectively. For coarser grains, hindered settling rates at all concentrations are much too high to form climbing‐ripple cross‐lamination, resulting in the formation of massive/structureless S 3 or T a divisions.

@article{doi101111j13653091201101283x,
    author = "Jobe, Zane and Lowe, Donald R. and Morris, William R.",
    title = "Climbing‐ripple successions in turbidite systems: depositional environments, sedimentation rates and accumulation times",
    year = "2011",
    journal = "Sedimentology",
    abstract = "Abstract Climbing‐ripple cross‐lamination is most commonly deposited by turbidity currents when suspended load fallout and bedload transport occur contemporaneously. The angle of ripple climb reflects the ratio of suspended load fallout and bedload sedimentation rates, allowing for the calculation of the flow properties and durations of turbidity currents. Three areas exhibiting thick (>50 m) sections of deep‐water climbing‐ripple cross‐lamination deposits are the focus of this study: (i) the Miocene upper Mount Messenger Formation in the Taranaki Basin, New Zealand; (ii) the Permian Skoorsteenberg Formation in the Tanqua depocentre of the Karoo Basin, South Africa; and (iii) the lower Pleistocene Magnolia Field in the Titan Basin, Gulf of Mexico. Facies distributions and local contextual information indicate that climbing‐ripple cross‐lamination in each area was deposited in an ‘off‐axis’ setting where flows were expanding due to loss of confinement or a decrease in slope gradient. The resultant reduction in flow thickness, Reynolds number, shear stress and capacity promoted suspension fallout and thus climbing‐ripple cross‐lamination formation. Climbing‐ripple cross‐lamination in the New Zealand study area was deposited both outside of and within channels at an inferred break in slope, where flows were decelerating and expanding. In the South Africa study area, climbing‐ripple cross‐lamination was deposited due to a loss of flow confinement. In the Magnolia study area, an abrupt decrease in gradient near a basin sill caused flow deceleration and climbing‐ripple cross‐lamination deposition in off‐axis settings. Sedimentation rate and accumulation time were calculated for 44 climbing‐ripple cross‐lamination sedimentation units from the three areas using TDURE, a mathematical model developed by Baas et al. (2000). For T c divisions and T bc beds averaging 26 cm and 37 cm thick, respectively, average climbing‐ripple cross‐lamination and whole bed sedimentation rates were 0·15 mm sec −1 and 0·26 mm sec −1 and average accumulation times were 27 min and 35 min, respectively. In some instances, distinct stratigraphic trends of sedimentation rate give insight into the evolution of the depositional environment. Climbing‐ripple cross‐lamination in the three study areas is developed in very fine‐grained to fine‐grained sand, suggesting a grain size dependence on turbidite climbing‐ripple cross‐lamination formation. Indeed, the calculated sedimentation rates correlate well with the rate of sedimentation due to hindered settling of very fine‐grained and fine‐grained sand–water suspensions at concentrations of up to 20\% and 2·5\%, respectively. For coarser grains, hindered settling rates at all concentrations are much too high to form climbing‐ripple cross‐lamination, resulting in the formation of massive/structureless S 3 or T a divisions.",
    url = "https://doi.org/10.1111/j.1365-3091.2011.01283.x",
    doi = "10.1111/j.1365-3091.2011.01283.x",
    openalex = "W1908834558",
    references = "doi101111j13653091200901073x, doi102110jsr2009035"
}

@incollection{posamentier2011deepwater,
    author = "POSAMENTIER, HENRY W. and WALKER, ROGER G.",
    title = "Deep-Water Turbidites and Submarine Fans",
    year = "2011",
    booktitle = "Facies Models Revisited",
    url = "https://doi.org/10.2110/pec.06.84.0399",
    doi = "10.2110/pec.06.84.0399",
    pages = "399-520"
}

Gravity-driven flows on the seafloor are the largest, yet least well understood, sediment transport agents on Earth. Recent exploration wells in ultradeep basins have revealed the presence of large sandy submarine fan systems of enigmatic facies types, many hundreds of kilometers from paleocoastlines. These sedimentary deposits often defy conventional turbidite or debrite interpretations, having a character suggestive of deposition from flows with transient turbulent-laminar rheologies. In the Wilcox Formation (Gulf of Mexico), inferred transitional flow deposits have distinctive stratigraphic stacking patterns, from fine-grained debrites to coarser grained turbidites. The vertical sequence of beds is here inferred to reflect the longitudinal bed distribution in response to lobe progradation, and demonstrates a transition from well-mixed turbulent flow, to progressively more rheologically stratified flow, and eventually to fully laminar flow. The progressive development of internal rheological boundaries resulted in a high-concentration but fluidal basal layer, and an upper quasi-laminar layer with an overriding sheared dilute turbidity current. The long runout of the flows is linked to their high silt and clay content; it is most likely flow expansion at the channel-lobe transition that drives flow transformation. This process-based model may be applicable to many deep-water settings and provides a framework within which to interpret the stratigraphic and spatial distribution of these complex deposits.

@article{doi101130g334101,
    author = "Kane, Ian and Pontén, Anna",
    title = "Submarine transitional flow deposits in the Paleogene Gulf of Mexico",
    year = "2012",
    journal = "Geology",
    abstract = "Gravity-driven flows on the seafloor are the largest, yet least well understood, sediment transport agents on Earth. Recent exploration wells in ultradeep basins have revealed the presence of large sandy submarine fan systems of enigmatic facies types, many hundreds of kilometers from paleocoastlines. These sedimentary deposits often defy conventional turbidite or debrite interpretations, having a character suggestive of deposition from flows with transient turbulent-laminar rheologies. In the Wilcox Formation (Gulf of Mexico), inferred transitional flow deposits have distinctive stratigraphic stacking patterns, from fine-grained debrites to coarser grained turbidites. The vertical sequence of beds is here inferred to reflect the longitudinal bed distribution in response to lobe progradation, and demonstrates a transition from well-mixed turbulent flow, to progressively more rheologically stratified flow, and eventually to fully laminar flow. The progressive development of internal rheological boundaries resulted in a high-concentration but fluidal basal layer, and an upper quasi-laminar layer with an overriding sheared dilute turbidity current. The long runout of the flows is linked to their high silt and clay content; it is most likely flow expansion at the channel-lobe transition that drives flow transformation. This process-based model may be applicable to many deep-water settings and provides a framework within which to interpret the stratigraphic and spatial distribution of these complex deposits.",
    url = "https://doi.org/10.1130/g33410.1",
    doi = "10.1130/g33410.1",
    openalex = "W2325095476",
    references = "doi101016jmarpetgeo200902012, doi101016jsedgeo201009010, doi101111j13653091200901073x"
}

Hybrid fl ows comprising both turbidity current and submarine debris fl ow are a signifi cant departure from many previous infl uential models for submarine sediment density fl ows. Hybrid beds containing cohesive debrite and turbidite are common in distal depositional environments, as shown by detailed observations from more than 20 modern and ancient systems worldwide. Hybrid fl ows, and cohesive debris fl ows more generally, are best classifi ed in terms of a continuum of decreasing cohesive debris fl ow strength. High-strength cohesive debris fl ows tend to be clast rich and relatively thick, and their deposit extends back to near the site of original slope failure. They are typically confi ned to higher gradient continental slopes, but may occasionally form megabeds on basin plains, in both cases overlain by a thin turbidite. Intermediate-strength cohesive debris fl ows typically contain clasts, but their deposits may be <1 or 2 m thick on low-gradient fan fringes, and are encased in turbidite sand and mud. Clasts may be fartraveled, and meter-sized clasts can be rafted long distances across very low gradients if they are less dense than surrounding fl ow. Low-strength cohesive debris fl ows generally lack mud clasts, and as cohesive strength decreases further there is a transition into fl uid mud layers that do not support sand. Intermediate-and low-strength cohesive debrites are consistently absent in more proximal parts of submarine systems, where faster moving sediment-charged fl ows are more likely to be turbulent. Intermediatestrength debris fl ows can run out for long distances on low gradients without hydroplaning. Very low strength cohesive debris fl ows most likely form through late-stage transformations near the site of debrite deposition, and emplaced gently to avoid mixing with surrounding seawater. The location and geometry of cohesive debrites in hybrid beds are controlled strongly by seafl oor morphology and small changes in gradient. Debrites occur as fringes around raised channel-levee ridges, or in the central and lowest parts of basin plains lacking such ridges. Small variations in mud fraction produce profound changes in cohesive strength, fl ow viscosity, permeability, and the time taken for excess pore pressures to dissipate that span multiple orders of magnitude. Reduction in fl ow speed can also cause substantial increases in viscosity and yield strength in shear thinning muddy fl uids. Small amounts of sediment can dampen or extinguish turbulence, especially as fl ow decelerates, affecting how sediment is supported or deposited. This ensures that cohesive debris fl ows and hybrid fl ows have a rich variety of behaviors.

@article{doi101130ges007931,
    author = "Talling, Peter J.",
    title = "Hybrid submarine flows comprising turbidity current and cohesive debris flow: Deposits, theoretical and experimental analyses, and generalized models",
    year = "2013",
    journal = "Geosphere",
    abstract = "Hybrid fl ows comprising both turbidity current and submarine debris fl ow are a signifi cant departure from many previous infl uential models for submarine sediment density fl ows. Hybrid beds containing cohesive debrite and turbidite are common in distal depositional environments, as shown by detailed observations from more than 20 modern and ancient systems worldwide. Hybrid fl ows, and cohesive debris fl ows more generally, are best classifi ed in terms of a continuum of decreasing cohesive debris fl ow strength. High-strength cohesive debris fl ows tend to be clast rich and relatively thick, and their deposit extends back to near the site of original slope failure. They are typically confi ned to higher gradient continental slopes, but may occasionally form megabeds on basin plains, in both cases overlain by a thin turbidite. Intermediate-strength cohesive debris fl ows typically contain clasts, but their deposits may be <1 or 2 m thick on low-gradient fan fringes, and are encased in turbidite sand and mud. Clasts may be fartraveled, and meter-sized clasts can be rafted long distances across very low gradients if they are less dense than surrounding fl ow. Low-strength cohesive debris fl ows generally lack mud clasts, and as cohesive strength decreases further there is a transition into fl uid mud layers that do not support sand. Intermediate-and low-strength cohesive debrites are consistently absent in more proximal parts of submarine systems, where faster moving sediment-charged fl ows are more likely to be turbulent. Intermediatestrength debris fl ows can run out for long distances on low gradients without hydroplaning. Very low strength cohesive debris fl ows most likely form through late-stage transformations near the site of debrite deposition, and emplaced gently to avoid mixing with surrounding seawater. The location and geometry of cohesive debrites in hybrid beds are controlled strongly by seafl oor morphology and small changes in gradient. Debrites occur as fringes around raised channel-levee ridges, or in the central and lowest parts of basin plains lacking such ridges. Small variations in mud fraction produce profound changes in cohesive strength, fl ow viscosity, permeability, and the time taken for excess pore pressures to dissipate that span multiple orders of magnitude. Reduction in fl ow speed can also cause substantial increases in viscosity and yield strength in shear thinning muddy fl uids. Small amounts of sediment can dampen or extinguish turbulence, especially as fl ow decelerates, affecting how sediment is supported or deposited. This ensures that cohesive debris fl ows and hybrid fl ows have a rich variety of behaviors.",
    url = "https://doi.org/10.1130/ges00793.1",
    doi = "10.1130/ges00793.1",
    openalex = "W2122272026",
    references = "doi101016jmarpetgeo200902012, doi1010292009jf001514, doi101038nature06273, doi101046j13653091199900204x, doi101046j13653091200100360x, doi101111j136530911995tb00395x, doi101111j13653091201201353x, doi101306212f7f312b2411d78648000102c1865d, doi102475ajs25012849, openalexw1570283708"
}

The contourite paradigm was conceived a few decades ago, yet there remains a need to establish a sound connection between contourite deposits, basin evolution and oceanographic processes. Significant recent advances have been enabled by various factors, including the establishment of two IGCP projects and the realisation of several IODP expeditions. Contourites were first described in the Northern and Southern Atlantic Ocean, and since then, have been discovered in every major ocean basin and even in lakes. The 120 major contourite areas presently known are associated to myriad oceanographic processes in surface, intermediate and deep-water masses. The increasing recognition of these deposits is influencing palaeoclimatology & palaeoceanography, slope-stability/geological hazard assessment, and hydrocarbon exploration. Nevertheless, there is a pressing need for a better understanding of the sedimentological and oceanographic processes governing contourites, which involve dense bottom currents, tides, eddies, deep-sea storms, internal waves and tsunamis. Furthermore, in light of the latest knowledge on oceanographic processes and other governing factors (e.g. sediment supply and sea-level), existing facies models must now be revised. Persistent oceanographic processes significantly affect the seafloor, resulting in large-scale depositional and erosional features. Various classifications have been proposed to subdivide a continuous spectrum of partly overlapping features. Although much progress has been made in the large-scale, geophysically based recognition of these deposits, there remains a lack of unambiguous and commonly accepted diagnostic criteria for deciphering the small-scaled contourite facies and for distinguishing them from turbidite ones. Similarly, the study of sandy deposits generated or affected by bottom currents, which is still in its infancy, offers great research potential: these deposits might prove invaluable as future reservoir targets. Expectations for the forthcoming analysis of data from the IODP Expedition 339 are high, as this work promises to tackle much of the aforementioned lack of knowledge. In the near future, geologists, oceanographers and benthic biologists will have to work in concert to achieve synergy in contourite research to demonstrate the importance of bottom currents in continental margin sedimentation and evolution.

@article{doi101016jmargeo201403011,
    author = "Rebesco, Michele and Hernández‐Molina, F. Javier and Rooij, David Van and Wåhlin, Anna",
    title = "Contourites and associated sediments controlled by deep-water circulation processes: State-of-the-art and future considerations",
    year = "2014",
    journal = "Marine Geology",
    abstract = "The contourite paradigm was conceived a few decades ago, yet there remains a need to establish a sound connection between contourite deposits, basin evolution and oceanographic processes. Significant recent advances have been enabled by various factors, including the establishment of two IGCP projects and the realisation of several IODP expeditions. Contourites were first described in the Northern and Southern Atlantic Ocean, and since then, have been discovered in every major ocean basin and even in lakes. The 120 major contourite areas presently known are associated to myriad oceanographic processes in surface, intermediate and deep-water masses. The increasing recognition of these deposits is influencing palaeoclimatology \& palaeoceanography, slope-stability/geological hazard assessment, and hydrocarbon exploration. Nevertheless, there is a pressing need for a better understanding of the sedimentological and oceanographic processes governing contourites, which involve dense bottom currents, tides, eddies, deep-sea storms, internal waves and tsunamis. Furthermore, in light of the latest knowledge on oceanographic processes and other governing factors (e.g. sediment supply and sea-level), existing facies models must now be revised. Persistent oceanographic processes significantly affect the seafloor, resulting in large-scale depositional and erosional features. Various classifications have been proposed to subdivide a continuous spectrum of partly overlapping features. Although much progress has been made in the large-scale, geophysically based recognition of these deposits, there remains a lack of unambiguous and commonly accepted diagnostic criteria for deciphering the small-scaled contourite facies and for distinguishing them from turbidite ones. Similarly, the study of sandy deposits generated or affected by bottom currents, which is still in its infancy, offers great research potential: these deposits might prove invaluable as future reservoir targets. Expectations for the forthcoming analysis of data from the IODP Expedition 339 are high, as this work promises to tackle much of the aforementioned lack of knowledge. In the near future, geologists, oceanographers and benthic biologists will have to work in concert to achieve synergy in contourite research to demonstrate the importance of bottom currents in continental margin sedimentation and evolution.",
    url = "https://doi.org/10.1016/j.margeo.2014.03.011",
    doi = "10.1016/j.margeo.2014.03.011",
    openalex = "W2145619152",
    references = "doi101016jearscirev201009010, doi101016jmarpetgeo201007008, doi101016s0264817299000112, doi101029ar071p0029, doi105670oceanog199107, doi105860choice301532, openalexw4306246725"
}

Normark in the early 1970s when I was revising my first paper on Amazon Fan based on the excellent review he had just provided. He had already become one of the foremost authorities on modern fans. After that, I had the good fortune to interact with Bill numerous times during his career including at meetings, collaboration on publications, and describing Amazon Fan cores together during Ocean Drilling Program Leg 155. Early on

@article{doi101130ges010901,
    author = "Damuth, John E. and Olson, Hilary Clement",
    title = "Latest Quaternary sedimentation in the northern Gulf of Mexico Intraslope Basin Province: I. Sediment facies and depositional processes",
    year = "2015",
    journal = "Geosphere",
    abstract = "Normark in the early 1970s when I was revising my first paper on Amazon Fan based on the excellent review he had just provided. He had already become one of the foremost authorities on modern fans. After that, I had the good fortune to interact with Bill numerous times during his career including at meetings, collaboration on publications, and describing Amazon Fan cores together during Ocean Drilling Program Leg 155. Early on",
    url = "https://doi.org/10.1130/ges01090.1",
    doi = "10.1130/ges01090.1",
    openalex = "W2194143925",
    references = "crossref1978gulf, doi101086627725"
}

When we look back the contributions on submarine fans during the past 65 years (1950–2015), the empirical data on 21 modern submarine fans and 10 ancient deep-water systems, published by the results of the First COMFAN (Committee on FANs) Meeting (Bouma et al., 1985a), have remained the single most significant compilation of data on submarine fans. The 1970s were the “heyday” of submarine fan models. In the 21st century, the general focus has shifted from submarine fans to submarine mass movements, internal waves and tides, and contourites. The purpose of this review is to illustrate the complexity of issues surrounding the origin and classification of submarine fans. The principal elements of submarine fans, composed of canyons, channels, and lobes, are discussed using nine modern case studies from the Mediterranean Sea, the Equatorial Atlantic, the Gulf of Mexico, the North Pacific, the NE Indian Ocean (Bay of Bengal), and the East Sea (Korea). The Annot Sandstone (Eocene–Oligocene), exposed at Peira-Cava area, SE France, which served as the type locality for the “Bouma Sequence”, was reexamined. The field details are documented in questioning the validity of the model, which was the basis for the turbidite-fan link. The 29 fan-related models that are of conceptual significance, developed during the period 1970–2015, are discussed using modern and ancient systems. They are: (1) the classic submarine fan model with attached lobes, (2) the detached-lobe model, (3) the channel-levee complex without lobes, (4) the delta-fed ramp model, (5) the gully-lobe model, (6) the suprafan lobe model, (7) the depositional lobe model, (8) the fan lobe model, (9) the ponded lobe model, (10) the nine models based on grain size and sediment source, (11) the four fan models based on tectonic settings, (12) the Jackfork debrite model, (13) the basin-floor fan model, (14) supercritical and subcritical fans, and (15) the three types of fan reservoirs. Each model is unique, and the long-standing belief that submarine fans are composed of turbidites, in particular, of gravelly and sandy high-density turbidites, is a myth. This is because there are no empirical data to validate the existence of gravelly and sandy high-density turbidity currents in the modern marine environments. Also, there are no experimental documentation of true turbidity currents that can transport gravels and coarse sands in turbulent suspension. Mass-transport processes, which include slides, slumps, and debris flows (but not turbidity currenrs), are the most viable mechanisms for transporting gravels and sands into the deep sea. The prevailing notion that submarine fans develop during periods of sea-level lowstands is also a myth. The geologic reality is that frequent short-term events that last for only a few minutes to several hours or days (e.g., earthquakes, meteorite impacts, tsunamis, tropical cyclones, etc.) are more important in controlling deposition of deep-water sands than sporadic long-term events that last for thousands to millions of years (e.g., lowstand systems tract). Submarine fans are still in a stage of muddled turbidite paradigm because the concept of high-density turbidity currents is incommensurable.

@article{doi101016jjop201508011,
    author = "Shanmugam, G.",
    title = "Submarine fans: A critical retrospective (1950–2015)",
    year = "2016",
    journal = "Journal of Palaeogeography",
    abstract = "When we look back the contributions on submarine fans during the past 65 years (1950–2015), the empirical data on 21 modern submarine fans and 10 ancient deep-water systems, published by the results of the First COMFAN (Committee on FANs) Meeting (Bouma et al., 1985a), have remained the single most significant compilation of data on submarine fans. The 1970s were the “heyday” of submarine fan models. In the 21st century, the general focus has shifted from submarine fans to submarine mass movements, internal waves and tides, and contourites. The purpose of this review is to illustrate the complexity of issues surrounding the origin and classification of submarine fans. The principal elements of submarine fans, composed of canyons, channels, and lobes, are discussed using nine modern case studies from the Mediterranean Sea, the Equatorial Atlantic, the Gulf of Mexico, the North Pacific, the NE Indian Ocean (Bay of Bengal), and the East Sea (Korea). The Annot Sandstone (Eocene–Oligocene), exposed at Peira-Cava area, SE France, which served as the type locality for the “Bouma Sequence”, was reexamined. The field details are documented in questioning the validity of the model, which was the basis for the turbidite-fan link. The 29 fan-related models that are of conceptual significance, developed during the period 1970–2015, are discussed using modern and ancient systems. They are: (1) the classic submarine fan model with attached lobes, (2) the detached-lobe model, (3) the channel-levee complex without lobes, (4) the delta-fed ramp model, (5) the gully-lobe model, (6) the suprafan lobe model, (7) the depositional lobe model, (8) the fan lobe model, (9) the ponded lobe model, (10) the nine models based on grain size and sediment source, (11) the four fan models based on tectonic settings, (12) the Jackfork debrite model, (13) the basin-floor fan model, (14) supercritical and subcritical fans, and (15) the three types of fan reservoirs. Each model is unique, and the long-standing belief that submarine fans are composed of turbidites, in particular, of gravelly and sandy high-density turbidites, is a myth. This is because there are no empirical data to validate the existence of gravelly and sandy high-density turbidity currents in the modern marine environments. Also, there are no experimental documentation of true turbidity currents that can transport gravels and coarse sands in turbulent suspension. Mass-transport processes, which include slides, slumps, and debris flows (but not turbidity currenrs), are the most viable mechanisms for transporting gravels and sands into the deep sea. The prevailing notion that submarine fans develop during periods of sea-level lowstands is also a myth. The geologic reality is that frequent short-term events that last for only a few minutes to several hours or days (e.g., earthquakes, meteorite impacts, tsunamis, tropical cyclones, etc.) are more important in controlling deposition of deep-water sands than sporadic long-term events that last for thousands to millions of years (e.g., lowstand systems tract). Submarine fans are still in a stage of muddled turbidite paradigm because the concept of high-density turbidity currents is incommensurable.",
    url = "https://doi.org/10.1016/j.jop.2015.08.011",
    doi = "10.1016/j.jop.2015.08.011",
    openalex = "W2309593205",
    references = "behrmann2006rapid, crossref1978gulf, crossref1996the, doi1010160012825286900012, doi10102997rg00426, doi101046j144016142002t01501102ax, doi10108000288306196910420225, doi101111j13653091200700926x, doi101111j13653091200801019x, doi101130081372356655, doi101130g332171, doi101130spe65p1, doi101144gslsp19850180103, doi101306212f7f312b2411d78648000102c1865d, doi1013065ceae13616bb11d78645000102c1865d, doi1043249781912281589, doi105860choice295709, doi105860choice342173, doi105860choice444462, doi107208chicago97802264581060010001, openalexw2267844404"
}

The heads of submarine canyons represent a critical link in the transfer of sediment from terrestrial sources to deep basin sinks. Here we report data on grain size, bathymetry, and geochronology from twenty-five modern submarine canyons that suggest this link to be very sensitive to the distance between the canyon head and the shoreline, and, to a lesser extent, wave energy. These data show the width of this zone filters the caliber of sediment delivered into deep water, which has significant implications for understanding sediment budgets and the distribution of reservoir and seal facies.

@article{doi102110jsr201664,
    author = "Sweet, Michael and Blum, Michael D.",
    title = "Connections Between Fluvial To Shallow Marine Environments and Submarine Canyons: Implications For Sediment Transfer To Deep Water",
    year = "2016",
    journal = "Journal of Sedimentary Research",
    abstract = "The heads of submarine canyons represent a critical link in the transfer of sediment from terrestrial sources to deep basin sinks. Here we report data on grain size, bathymetry, and geochronology from twenty-five modern submarine canyons that suggest this link to be very sensitive to the distance between the canyon head and the shoreline, and, to a lesser extent, wave energy. These data show the width of this zone filters the caliber of sediment delivered into deep water, which has significant implications for understanding sediment budgets and the distribution of reservoir and seal facies.",
    url = "https://doi.org/10.2110/jsr.2016.64",
    doi = "10.2110/jsr.2016.64",
    openalex = "W2538757038",
    references = "doi101007bf02431072, doi101016jearscirev200906008, doi10130607010404023"
}

Abstract This paper presents a model of facies distribution within a set of early Cretaceous, deep‐lacustrine, partially confined turbidite fans (Sea Lion Fan, Sea Lion North Fan and Otter Fan) in the North Falkland Basin, South Atlantic. As a whole, ancient deep‐lacustrine turbidite systems are under‐represented in the literature when compared with those documented in marine basins. Lacustrine turbidite systems can form extensive, good quality hydrocarbon reservoirs, making the understanding of such systems crucial to exploration within lacustrine basins. An integrated analysis of seismic cross‐sections, seismic amplitude extraction maps and 455 m of core has enabled the identification of a series of turbidite fans. The deposits of these fans have been separated into lobe axis, lobe fringe and lobe distal fringe settings. Seismic architectures, observed in the seismic amplitude extraction maps, are interpreted to represent geologically associated heterogeneities, including: feeder systems, terminal mouth lobes, flow deflection, sinuous lobe axis deposits, flow constriction and stranded lobe fringe areas. When found in combination, these architectures suggest ‘partial confinement’ of a system, something that appears to be a key feature in the lacustrine turbidite setting of the North Falkland Basin. Partial confinement of a system occurs when depositionally generated topography controls the flow‐pathway and deposition of subsequent turbidite fan deposits. The term ‘partial confinement’ provides an expression for categorising a system whose depositional boundaries are unconfined by the margins of the basin, yet exhibit evidence of internal confinement, primarily controlled by depositional topography. Understanding the controls that dictate partial confinement; and the resultant distribution of sand‐prone facies within deep‐lacustrine turbidite fans, is important, particularly considering their recent rise as hydrocarbon reservoirs in rift and failed‐rift settings.

@article{doi101111sed12483,
    author = "Dodd, Thomas J.H. and McCarthy, David and Richards, Philip C.",
    title = "A depositional model for deep‐lacustrine, partially confined, turbidite fans: Early Cretaceous, North Falkland Basin",
    year = "2018",
    journal = "Sedimentology",
    abstract = "Abstract This paper presents a model of facies distribution within a set of early Cretaceous, deep‐lacustrine, partially confined turbidite fans (Sea Lion Fan, Sea Lion North Fan and Otter Fan) in the North Falkland Basin, South Atlantic. As a whole, ancient deep‐lacustrine turbidite systems are under‐represented in the literature when compared with those documented in marine basins. Lacustrine turbidite systems can form extensive, good quality hydrocarbon reservoirs, making the understanding of such systems crucial to exploration within lacustrine basins. An integrated analysis of seismic cross‐sections, seismic amplitude extraction maps and 455 m of core has enabled the identification of a series of turbidite fans. The deposits of these fans have been separated into lobe axis, lobe fringe and lobe distal fringe settings. Seismic architectures, observed in the seismic amplitude extraction maps, are interpreted to represent geologically associated heterogeneities, including: feeder systems, terminal mouth lobes, flow deflection, sinuous lobe axis deposits, flow constriction and stranded lobe fringe areas. When found in combination, these architectures suggest ‘partial confinement’ of a system, something that appears to be a key feature in the lacustrine turbidite setting of the North Falkland Basin. Partial confinement of a system occurs when depositionally generated topography controls the flow‐pathway and deposition of subsequent turbidite fan deposits. The term ‘partial confinement’ provides an expression for categorising a system whose depositional boundaries are unconfined by the margins of the basin, yet exhibit evidence of internal confinement, primarily controlled by depositional topography. Understanding the controls that dictate partial confinement; and the resultant distribution of sand‐prone facies within deep‐lacustrine turbidite fans, is important, particularly considering their recent rise as hydrocarbon reservoirs in rift and failed‐rift settings.",
    url = "https://doi.org/10.1111/sed.12483",
    doi = "10.1111/sed.12483",
    openalex = "W2797029103",
    references = "doi101111sed12376"
}

Submarine channel-lobe transition zones separate well-defined channels from welldefined lobes and form morphologically complicated areas, commonly located at breaks in slope. These areas play a vital role in the transfer of sediment through deep-water systems. Extensive outcrop exposures in the Karoo Basin, South Africa, permit investigation of the depositional architecture and evolution of entirely exhumed dip transects of a channel-lobe transition zone for the first time. Furthermore, the excellent paleogeographic constraint allows correlation to genetically related updip channel-levee systems and downdip lobe deposits over 40 km, with strike control over 20 km. Unlike the single time slice afforded by modern systems, the Karoo example uniquely allows study of the temporal shifting of the channel-lobe transition zone and transfer into the stratigraphic record. Key lateral changes along the base of slope include the variation from an interfingering levee-lobe transition zone to a bypass-dominated channel-lobe transition zone over a width of 14 km. Key recognition criteria for channel-lobe transition zones in the ancient record include combinations of scours and megaflutes, composite erosional surfaces, mudstone clast/coarse-grained sediment lags, and remnants of depositional bed forms, such as sediment waves. Documented here in a single channel-lobe transition zone, these features are arranged in a zone of juxtaposed remnant erosional and depositional features. The zone reaches 6 km in length, formed by at least four stages of expansion/contraction or migration. Strike variations and changes in the dimensions of the channel-lobe transition zone through time are interpreted to be the result of physiographic changes and variations in flow dynamics across the base of slope. The dynamic nature of channellobe transition zones results in complicated and composite stratigraphy, with preservation potential generally low but increasing distally and laterally away from the mouth of the feeder channel system. Here, we present the first generic model to account for dynamic channel-lobe transition zone development, encompassing distinctive recognition criteria, fluctuations in the morphology and position of the zone, and the complex transfer into the sedimentary record.

@article{doi101130b317141,
    author = "Brooks, Hannah L. and Hodgson, David M. and Brunt, Rufus L. and Peakall, Jeff and Hofstra, Menno and Flint, Stephen S.",
    title = "Deep-water channel-lobe transition zone dynamics: Processes and depositional architecture, an example from the Karoo Basin, South Africa",
    year = "2018",
    journal = "Geological Society of America Bulletin",
    abstract = "Submarine channel-lobe transition zones separate well-defined channels from welldefined lobes and form morphologically complicated areas, commonly located at breaks in slope. These areas play a vital role in the transfer of sediment through deep-water systems. Extensive outcrop exposures in the Karoo Basin, South Africa, permit investigation of the depositional architecture and evolution of entirely exhumed dip transects of a channel-lobe transition zone for the first time. Furthermore, the excellent paleogeographic constraint allows correlation to genetically related updip channel-levee systems and downdip lobe deposits over 40 km, with strike control over 20 km. Unlike the single time slice afforded by modern systems, the Karoo example uniquely allows study of the temporal shifting of the channel-lobe transition zone and transfer into the stratigraphic record. Key lateral changes along the base of slope include the variation from an interfingering levee-lobe transition zone to a bypass-dominated channel-lobe transition zone over a width of 14 km. Key recognition criteria for channel-lobe transition zones in the ancient record include combinations of scours and megaflutes, composite erosional surfaces, mudstone clast/coarse-grained sediment lags, and remnants of depositional bed forms, such as sediment waves. Documented here in a single channel-lobe transition zone, these features are arranged in a zone of juxtaposed remnant erosional and depositional features. The zone reaches 6 km in length, formed by at least four stages of expansion/contraction or migration. Strike variations and changes in the dimensions of the channel-lobe transition zone through time are interpreted to be the result of physiographic changes and variations in flow dynamics across the base of slope. The dynamic nature of channellobe transition zones results in complicated and composite stratigraphy, with preservation potential generally low but increasing distally and laterally away from the mouth of the feeder channel system. Here, we present the first generic model to account for dynamic channel-lobe transition zone development, encompassing distinctive recognition criteria, fluctuations in the morphology and position of the zone, and the complex transfer into the sedimentary record.",
    url = "https://doi.org/10.1130/b31714.1",
    doi = "10.1130/b31714.1",
    openalex = "W2796516379",
    references = "doi101130ges007931"
}

Abstract Deep‐water mudstones are often considered as background sediments, deposited by vertical suspension fallout, and the range of transport and depositional processes are poorly understood compared with their shallow‐marine counterparts. This study presents a dataset from a 538·50 m thick cored succession through the Permian muddy lower Ecca Group of the Tanqua depocentre (south‐west Karoo Basin, South Africa). This study aims to characterize the range of mudstone facies, transport and depositional processes, and stacking patterns recorded in deep‐water environments prior to deposition of the Tanqua Karoo sandy basin‐floor fans. A combination of macroscopic and microscopic description techniques and ichnological analysis has defined nine sedimentary facies that stack in a repeated pattern to produce 2 to 26 m thick depositional units. The lower part of each unit is characterized by bedded mudstone deposited by dilute, low‐density turbidity currents with evidence for hyperpycnal‐flow processes and sediment remobilization. The upper part of each unit is dominated by more organic‐rich bedded mudstone with common mudstone intraclasts, deposited by debris flows and transitional flows, with scarce indicators of suspension fallout. The intensity of bioturbation and burrow size increases upward through each depositional unit, consistent with a decrease in physicochemically stressed conditions, linked to a lower sediment accumulation rate. This vertical facies transition in the single well dataset can be interpreted to represent relative sea‐level variations; the hyperpycnal stressed conditions in the lower part of the units were driven by relative sea‐level fall, and the more bioturbated upper part of the units represent backstepping, related to relative sea‐level rise. Alternatively, this facies transition may represent autogenic compensational stacking. The prevalence of sediment density flow deposits, even in positions distal or lateral to the sediment entry point, challenges the idea that deep‐water mudstones are primarily the deposits of passive rainout along continental margins.

@article{doi101111sed12614,
    author = "Boulesteix, Kévin and Poyatos‐Moré, Miquel and Flint, Stephen S. and Taylor, Kevin G. and Hodgson, David M. and Hasiotis, Stephen T.",
    title = "Transport and deposition of mud in deep‐water environments: Processes and stratigraphic implications",
    year = "2019",
    journal = "Sedimentology",
    abstract = "Abstract Deep‐water mudstones are often considered as background sediments, deposited by vertical suspension fallout, and the range of transport and depositional processes are poorly understood compared with their shallow‐marine counterparts. This study presents a dataset from a 538·50 m thick cored succession through the Permian muddy lower Ecca Group of the Tanqua depocentre (south‐west Karoo Basin, South Africa). This study aims to characterize the range of mudstone facies, transport and depositional processes, and stacking patterns recorded in deep‐water environments prior to deposition of the Tanqua Karoo sandy basin‐floor fans. A combination of macroscopic and microscopic description techniques and ichnological analysis has defined nine sedimentary facies that stack in a repeated pattern to produce 2 to 26 m thick depositional units. The lower part of each unit is characterized by bedded mudstone deposited by dilute, low‐density turbidity currents with evidence for hyperpycnal‐flow processes and sediment remobilization. The upper part of each unit is dominated by more organic‐rich bedded mudstone with common mudstone intraclasts, deposited by debris flows and transitional flows, with scarce indicators of suspension fallout. The intensity of bioturbation and burrow size increases upward through each depositional unit, consistent with a decrease in physicochemically stressed conditions, linked to a lower sediment accumulation rate. This vertical facies transition in the single well dataset can be interpreted to represent relative sea‐level variations; the hyperpycnal stressed conditions in the lower part of the units were driven by relative sea‐level fall, and the more bioturbated upper part of the units represent backstepping, related to relative sea‐level rise. Alternatively, this facies transition may represent autogenic compensational stacking. The prevalence of sediment density flow deposits, even in positions distal or lateral to the sediment entry point, challenges the idea that deep‐water mudstones are primarily the deposits of passive rainout along continental margins.",
    url = "https://doi.org/10.1111/sed.12614",
    doi = "10.1111/sed.12614",
    openalex = "W2937958085",
    references = "doi1010160012825286900012, doi101016jmarpetgeo201006008, doi10130613271349st613438, openalexw2247901322"
}

An estimated 8.3 billion tonnes of non-biodegradable plastic has been produced over the last 65 years. Much of this is not recycled or disposed of ‘properly’, has a long environmental residence time and accumulates in sedimentary systems worldwide, posing a threat to important ecosystems and potentially human health. We synthesise existing knowledge of seafloor microplastic distribution, and integrate this with process-based sedimentological models of particle transport, to provide new insights, and critically, to identify future research challenges. Compilation of published data shows that microplastics pervade the global seafloor, from abyssal plains to submarine canyons and deep-sea trenches. However, few studies relate microplastic accumulation to sediment transport and deposition. Microplastics may enter directly into the sea as marine litter from shipping and fishing, or indirectly via fluvial and aeolian systems from terrestrial environments. The nature of the entry-point is critical to how terrestrially-sourced microplastics are transferred to offshore sedimentary systems. We present models for physiographic shelf connection types related to the tectono-sedimentary regime of the margin. Beyond the shelf, the principal agents for microplastic transport are: i) gravity-driven transport in sediment-laden flows; ii) settling, or conveyance through biological processes, of material that was formerly floating on the surface or suspended in the water column; iii) transport by thermohaline currents, either during settling or by reworking of deposited microplastics. We compare microplastic settling velocities to natural sediments to understand how appropriate existing sediment transport models are for explaining microplastic dispersal. Based on this analysis, and the relatively well-known behaviour or deep-marine flow types, we explore the expected distribution of microplastic particles, both in individual sedimentary event deposits and within deep-marine depositional systems. Residence time within certain deposit types and depositional environments is anticipated to be variable, which has implications for the likelihood of ingestion and incorporation into the food chain, further transport, or deeper burial. We conclude that integration of process-based sedimentological and stratigraphic knowledge with insights from modern sedimentary systems, and biological activity within them, will provide essential constraints on the transfer of microplastics to deep-marine environments, their distribution and ultimate fate, and the implications that these have for benthic ecosystems.

@article{doi103389feart201900080,
    author = "Kane, Ian and Clare, Michael",
    title = "Dispersion, Accumulation, and the Ultimate Fate of Microplastics in Deep-Marine Environments: A Review and Future Directions",
    year = "2019",
    journal = "Frontiers in Earth Science",
    abstract = "An estimated 8.3 billion tonnes of non-biodegradable plastic has been produced over the last 65 years. Much of this is not recycled or disposed of ‘properly’, has a long environmental residence time and accumulates in sedimentary systems worldwide, posing a threat to important ecosystems and potentially human health. We synthesise existing knowledge of seafloor microplastic distribution, and integrate this with process-based sedimentological models of particle transport, to provide new insights, and critically, to identify future research challenges. Compilation of published data shows that microplastics pervade the global seafloor, from abyssal plains to submarine canyons and deep-sea trenches. However, few studies relate microplastic accumulation to sediment transport and deposition. Microplastics may enter directly into the sea as marine litter from shipping and fishing, or indirectly via fluvial and aeolian systems from terrestrial environments. The nature of the entry-point is critical to how terrestrially-sourced microplastics are transferred to offshore sedimentary systems. We present models for physiographic shelf connection types related to the tectono-sedimentary regime of the margin. Beyond the shelf, the principal agents for microplastic transport are: i) gravity-driven transport in sediment-laden flows; ii) settling, or conveyance through biological processes, of material that was formerly floating on the surface or suspended in the water column; iii) transport by thermohaline currents, either during settling or by reworking of deposited microplastics. We compare microplastic settling velocities to natural sediments to understand how appropriate existing sediment transport models are for explaining microplastic dispersal. Based on this analysis, and the relatively well-known behaviour or deep-marine flow types, we explore the expected distribution of microplastic particles, both in individual sedimentary event deposits and within deep-marine depositional systems. Residence time within certain deposit types and depositional environments is anticipated to be variable, which has implications for the likelihood of ingestion and incorporation into the food chain, further transport, or deeper burial. We conclude that integration of process-based sedimentological and stratigraphic knowledge with insights from modern sedimentary systems, and biological activity within them, will provide essential constraints on the transfer of microplastics to deep-marine environments, their distribution and ultimate fate, and the implications that these have for benthic ecosystems.",
    url = "https://doi.org/10.3389/feart.2019.00080",
    doi = "10.3389/feart.2019.00080",
    openalex = "W2942579012",
    references = "doi101016jenvpol201302031, doi101016jmarpetgeo200301003, doi101016jmarpolbul201105030, doi101016jmarpolbul201109025, doi101021es201811s, doi101038ncomms15611, doi101098rstb20080205, doi101111j13653091201201353x, doi101126sciadv1700782, doi101126science1094559, doi101126science1260352, doi1013062f9182e316ce11d78645000102c1865d, doi101371journalpone0111913, nardin1979a"
}

The threat posed by plastic pollution to marine ecosystems and human health is under increasing scrutiny. Much of the macro- and microplastic in the ocean ends up on the seafloor, with some of the highest concentrations reported in submarine canyons that intersect the continental shelf and directly connect to terrestrial plastic sources. Gravity-driven avalanches, known as turbidity currents, are the primary process for delivering terrestrial sediment and organic carbon to the deep sea through submarine canyons. However, the ability of turbidity currents to transport and bury plastics is essentially unstudied. Using flume experiments, we investigate how turbidity currents transport microplastics, and their role in differential burial of microplastic fragments and fibers. We show that microplastic fragments become relatively concentrated within the base of turbidity currents, whereas fibers are more homogeneously distributed throughout the flow. Surprisingly, the resultant deposits show an opposing trend, as they are enriched with fibers, rather than fragments. We explain this apparent contradiction by a depositional mechanism whereby fibers are preferentially removed from suspension and buried in the deposits as they are trapped between settling sand-grains. Our results suggest that turbidity currents potentially distribute and bury large quantities of microplastics in seafloor sediments.

@article{doi101021acsest9b07527,
    author = "Pohl, Florian and Eggenhuisen, Joris T. and Kane, Ian and Clare, Michael",
    title = "Transport and Burial of Microplastics in Deep-Marine Sediments by Turbidity Currents",
    year = "2020",
    journal = "Environmental Science \& Technology",
    abstract = "The threat posed by plastic pollution to marine ecosystems and human health is under increasing scrutiny. Much of the macro- and microplastic in the ocean ends up on the seafloor, with some of the highest concentrations reported in submarine canyons that intersect the continental shelf and directly connect to terrestrial plastic sources. Gravity-driven avalanches, known as turbidity currents, are the primary process for delivering terrestrial sediment and organic carbon to the deep sea through submarine canyons. However, the ability of turbidity currents to transport and bury plastics is essentially unstudied. Using flume experiments, we investigate how turbidity currents transport microplastics, and their role in differential burial of microplastic fragments and fibers. We show that microplastic fragments become relatively concentrated within the base of turbidity currents, whereas fibers are more homogeneously distributed throughout the flow. Surprisingly, the resultant deposits show an opposing trend, as they are enriched with fibers, rather than fragments. We explain this apparent contradiction by a depositional mechanism whereby fibers are preferentially removed from suspension and buried in the deposits as they are trapped between settling sand-grains. Our results suggest that turbidity currents potentially distribute and bury large quantities of microplastics in seafloor sediments.",
    url = "https://doi.org/10.1021/acs.est.9b07527",
    doi = "10.1021/acs.est.9b07527",
    openalex = "W3010378517",
    references = "doi101016jmarpetgeo201506007, doi101016jsedgeo201009010, doi101021acsest8b05297, doi101021acsest9b01517, doi101038ncomms15611, doi101088174893261012124006, doi101098rsos140317, doi101126sciadv1700782, doi101126science1094559, doi101126science1260352, doi101371journalpone0111913, doi102305iucnch201701en, doi103389feart201900080"
}

Abstract The fringe of fine‐grained deep‐marine systems often exhibits complex sedimentary facies and facies associations, because the presence of clay promotes the development of transient turbulent flows with complex depositional properties. Relatively little is known about the variation of current‐induced sedimentary structures found within these facies. This study provides the first comprehensive description and interpretation of mixed sandstone–mudstone bedforms observed in the fringe of the mud‐rich submarine fan that makes up the Aberystwyth Grits Group and Borth Mudstone Formation (Wales, UK). Using textural and structural descriptions, 158 bedforms in sediment gravity flow deposits were characterized into three main types: ‘classic’ sandy current ripples, large current ripples and low‐amplitude bed‐waves. The sandy current ripples comprise clean sandstone, with average heights and lengths of 11 mm and 141 mm, respectively. The large current ripples are composed of mixed sandstone–mudstone and possess greater dimensions than the sandy current ripples, with an average height of 19 mm and an average length of 274 mm. The low‐amplitude bed‐waves are long thin bedforms composed commonly of mixed sandstone–mudstone, with an average height and length of 10 mm and 354 mm, respectively. The large current ripples and low‐amplitude bed‐waves are strikingly similar to experimental bedforms produced under decelerating mixed sand–mud flows and are interpreted to form beneath transitional flows with enhanced and attenuated near‐bed turbulence, respectively. From the fringe to the distal fringe of the fan, the dominant bedform type changed from sandy current ripples, via large current ripples, to low‐amplitude bed‐waves, suggesting that the flows changed from turbulent to increasingly turbulence‐modulated. It is proposed that the flow Reynolds number reduced, reflecting this flow transformation, from a combination of constant or decreasing flow height, flow deceleration from sediment deposition, and increasing flow viscosity due to the shear‐thinning nature of clay‐rich suspensions. Large current ripples and low‐amplitude bed‐waves are likely to be common in the fringe of other submarine fans. The presence and spatial trends in mixed sand–mud bedform types may be an important tool in interpreting fan fringe environments.

@article{doi101111sed12714,
    author = "Baker, Megan L. and Baas, Jaco H.",
    title = "Mixed sand–mud bedforms produced by transient turbulent flows in the fringe of submarine fans: Indicators of flow transformation",
    year = "2020",
    journal = "Sedimentology",
    abstract = "Abstract The fringe of fine‐grained deep‐marine systems often exhibits complex sedimentary facies and facies associations, because the presence of clay promotes the development of transient turbulent flows with complex depositional properties. Relatively little is known about the variation of current‐induced sedimentary structures found within these facies. This study provides the first comprehensive description and interpretation of mixed sandstone–mudstone bedforms observed in the fringe of the mud‐rich submarine fan that makes up the Aberystwyth Grits Group and Borth Mudstone Formation (Wales, UK). Using textural and structural descriptions, 158 bedforms in sediment gravity flow deposits were characterized into three main types: ‘classic’ sandy current ripples, large current ripples and low‐amplitude bed‐waves. The sandy current ripples comprise clean sandstone, with average heights and lengths of 11 mm and 141 mm, respectively. The large current ripples are composed of mixed sandstone–mudstone and possess greater dimensions than the sandy current ripples, with an average height of 19 mm and an average length of 274 mm. The low‐amplitude bed‐waves are long thin bedforms composed commonly of mixed sandstone–mudstone, with an average height and length of 10 mm and 354 mm, respectively. The large current ripples and low‐amplitude bed‐waves are strikingly similar to experimental bedforms produced under decelerating mixed sand–mud flows and are interpreted to form beneath transitional flows with enhanced and attenuated near‐bed turbulence, respectively. From the fringe to the distal fringe of the fan, the dominant bedform type changed from sandy current ripples, via large current ripples, to low‐amplitude bed‐waves, suggesting that the flows changed from turbulent to increasingly turbulence‐modulated. It is proposed that the flow Reynolds number reduced, reflecting this flow transformation, from a combination of constant or decreasing flow height, flow deceleration from sediment deposition, and increasing flow viscosity due to the shear‐thinning nature of clay‐rich suspensions. Large current ripples and low‐amplitude bed‐waves are likely to be common in the fringe of other submarine fans. The presence and spatial trends in mixed sand–mud bedform types may be an important tool in interpreting fan fringe environments.",
    url = "https://doi.org/10.1111/sed.12714",
    doi = "10.1111/sed.12714",
    openalex = "W3003769838",
    references = "doi101111sed12376"
}

Abstract Flutes and tool marks are commonly observed sedimentary structures on the bases of sandstones in deep‐water successions. These sole structures are universally used as palaeocurrent indicators but, in sharp contrast to most sedimentary structures, they are not used in palaeohydraulic reconstructions or to aid prediction of the spatial distribution of sediments. Since Kuenen's famous 1953 paper, flutes and tool marks in deep‐water systems have been linked to turbidity currents, as reflected in the standard Bouma sequence taught to generations of geologists. Yet, these structures present a series of unaddressed enigmas. Detailed field studies in the 1960s and early 1970s observed that flutes are typically associated with thicker, more proximal beds, whilst tools are generally prevalent in thinner, more distal, beds. Additionally, flutes and tool marks are rarely observed on the same surfaces, and flutes are seen to change downstream from larger wider parabolic to smaller narrower spindle‐shaped forms. No model has been proposed that explains these field‐based observations. This contribution undertakes a radical re‐examination of the formative flow conditions of flutes and tool marks, and demonstrates that they are the products of a wide range of sediment gravity flows, from turbulent flows, through transitional clay‐rich flows, to debris flows. Flutes are not solely the product of turbulent flows, but can continue to form in transitional flows. Grooves are shown to be formed by debris flows, slumps and slides, not turbidity currents, and in many cases the debris flows are linked to the debritic component of hybrid flows. Discontinuous tool marks, including skim (bounce) marks, prod marks and skip marks, are shown to be formed by transitional mud‐rich flows. Consequently, the observed spatial distribution of flutes and tool marks can be explained by a progressive increase in flow cohesivity downstream. This model of flutes and tool marks dovetails with models of hybrid flows that predict such a longitudinal increase in flow cohesivity. However, some deposits show grooves preferentially associated with Bouma T A beds, and these are likely formed by flows transforming from higher to lower cohesion, and are present in basins where hybrid beds are absent or rare. The recognition that sole structures may have no genetic link to the later overlying turbidity current deposits, and can be formed by a wide range of flow types, indicates that the existing pictorial description of the Bouma sequence is incorrect. A modified Bouma sequence is proposed here that addresses these points. In utilizing the advances in fluid dynamics since Kuenen's pioneering research, this study demonstrates that it is possible to use flutes and tool marks to interpret flow type at the point of formation, the nature of flow transformations, and the mechanics of the basal layer. These advances suggest that it is then possible to predict the nature of deposit type down‐dip. This new understanding, in combination with further testing in outcrop of the proposed relationships between sole marks and palaeohydraulics, opens up a wealth of possibilities for improving the understanding of deep‐water clastic environments, with implications for developing more complete facies models, assessing subaqueous geohazards and the resilience of seafloor infrastructure, and advancing our understanding of deep‐water sediments as archives of palaeoenvironmental change.

@article{doi101111sed12727,
    author = "Peakall, Jeff and Best, Jim and Baas, Jaco H. and Hodgson, David M. and Clare, Michael and Talling, Peter J. and Dorrell, R. M. and Lee, David R.",
    title = "An integrated process‐based model of flutes and tool marks in deep‐water environments: Implications for palaeohydraulics, the Bouma sequence and hybrid event beds",
    year = "2020",
    journal = "Sedimentology",
    abstract = "Abstract Flutes and tool marks are commonly observed sedimentary structures on the bases of sandstones in deep‐water successions. These sole structures are universally used as palaeocurrent indicators but, in sharp contrast to most sedimentary structures, they are not used in palaeohydraulic reconstructions or to aid prediction of the spatial distribution of sediments. Since Kuenen's famous 1953 paper, flutes and tool marks in deep‐water systems have been linked to turbidity currents, as reflected in the standard Bouma sequence taught to generations of geologists. Yet, these structures present a series of unaddressed enigmas. Detailed field studies in the 1960s and early 1970s observed that flutes are typically associated with thicker, more proximal beds, whilst tools are generally prevalent in thinner, more distal, beds. Additionally, flutes and tool marks are rarely observed on the same surfaces, and flutes are seen to change downstream from larger wider parabolic to smaller narrower spindle‐shaped forms. No model has been proposed that explains these field‐based observations. This contribution undertakes a radical re‐examination of the formative flow conditions of flutes and tool marks, and demonstrates that they are the products of a wide range of sediment gravity flows, from turbulent flows, through transitional clay‐rich flows, to debris flows. Flutes are not solely the product of turbulent flows, but can continue to form in transitional flows. Grooves are shown to be formed by debris flows, slumps and slides, not turbidity currents, and in many cases the debris flows are linked to the debritic component of hybrid flows. Discontinuous tool marks, including skim (bounce) marks, prod marks and skip marks, are shown to be formed by transitional mud‐rich flows. Consequently, the observed spatial distribution of flutes and tool marks can be explained by a progressive increase in flow cohesivity downstream. This model of flutes and tool marks dovetails with models of hybrid flows that predict such a longitudinal increase in flow cohesivity. However, some deposits show grooves preferentially associated with Bouma T A beds, and these are likely formed by flows transforming from higher to lower cohesion, and are present in basins where hybrid beds are absent or rare. The recognition that sole structures may have no genetic link to the later overlying turbidity current deposits, and can be formed by a wide range of flow types, indicates that the existing pictorial description of the Bouma sequence is incorrect. A modified Bouma sequence is proposed here that addresses these points. In utilizing the advances in fluid dynamics since Kuenen's pioneering research, this study demonstrates that it is possible to use flutes and tool marks to interpret flow type at the point of formation, the nature of flow transformations, and the mechanics of the basal layer. These advances suggest that it is then possible to predict the nature of deposit type down‐dip. This new understanding, in combination with further testing in outcrop of the proposed relationships between sole marks and palaeohydraulics, opens up a wealth of possibilities for improving the understanding of deep‐water clastic environments, with implications for developing more complete facies models, assessing subaqueous geohazards and the resilience of seafloor infrastructure, and advancing our understanding of deep‐water sediments as archives of palaeoenvironmental change.",
    url = "https://doi.org/10.1111/sed.12727",
    doi = "10.1111/sed.12727",
    openalex = "W3011315171",
    references = "doi101016jgeomorph201512008, doi101016jmarpetgeo201402016, doi101016jsedgeo201603008, doi101111bre12150, doi101111sed12376, doi101130b309961, doi101130ges007931"
}

Abstract Despite numerous efforts to properly differentiate between contourites and other deep‐water deposits in cores and outcrops, reliable diagnostic criteria are still lacking. The co‐occurrence of downslope and along‐slope sedimentary processes makes it particularly difficult to differentiate these relatively homogeneous deposits. The main aim of this paper is to identify differences in deep‐water sediments based on Principal Component Analysis of grain size and geochemistry, sedimentary facies, and reinforced by microfacies and ichnofacies. The sediments studied were obtained from two International Ocean Drilling Program Expedition 339 sites in mounded and sheeted drifts in the Gulf of Cadiz. The statistical approach led to the discernment of hemipelagites, silty contourites, sandy contourites, bottom current reworked sands, fine‐grained turbidites and debrites over a range of depositional and physiographic elements. These elements are linked to contourite drifts, the drift‐channel transition, the contourite channel and distal upper slope. When bottom currents or gravity‐driven flows are not the dominant depositional process, marine productivity and continental input settling forms the main depositional mechanism in deep‐water environments. This is reflected by a high variability of the first principal component in hemipelagic deposits. The stacked principal component variability of these deposits evidences that the contourite drift and the adjacent contourite channel were influenced by the interrelation of hemipelagic, gravitational and bottom current induced depositional processes. This interrelation questions the paradigm that a drift is made up solely of muddy sediments. The interrelation of sedimentary processes is a consequence of the precession‐driven changes in the intensity of the Mediterranean Outflow Water related to Mediterranean climate variability, which are punctuated by millennial‐scale variability. Associated vertical and lateral shifts of the Mediterranean Outflow Water, and therefore of its interface with the East North Atlantic Central Water, controlled sediment input and favoured turbulent sediment transport in the middle slope. During the interglacial precession maxima/insolation minima, a more vigorous upper core of the Mediterranean Outflow Water and the enhanced impact of the East North Atlantic Central Water – Mediterranean Outflow Water interface allowed for the development of the sandier contourite deposits.

@article{doi101111sed12813,
    author = "Castro, S. De and Hernández‐Molina, F. Javier and de Weger, Wouter and Jiménez-Espejo, F.J. and Rodrı́guez-Tovar, Francisco J. and Mena, Anxo and Llave, Estefanía and Sierro, Francisco Javier",
    title = "Contourite characterization and its discrimination from other deep‐water deposits in the Gulf of Cadiz contourite depositional system",
    year = "2020",
    journal = "Sedimentology",
    abstract = "Abstract Despite numerous efforts to properly differentiate between contourites and other deep‐water deposits in cores and outcrops, reliable diagnostic criteria are still lacking. The co‐occurrence of downslope and along‐slope sedimentary processes makes it particularly difficult to differentiate these relatively homogeneous deposits. The main aim of this paper is to identify differences in deep‐water sediments based on Principal Component Analysis of grain size and geochemistry, sedimentary facies, and reinforced by microfacies and ichnofacies. The sediments studied were obtained from two International Ocean Drilling Program Expedition 339 sites in mounded and sheeted drifts in the Gulf of Cadiz. The statistical approach led to the discernment of hemipelagites, silty contourites, sandy contourites, bottom current reworked sands, fine‐grained turbidites and debrites over a range of depositional and physiographic elements. These elements are linked to contourite drifts, the drift‐channel transition, the contourite channel and distal upper slope. When bottom currents or gravity‐driven flows are not the dominant depositional process, marine productivity and continental input settling forms the main depositional mechanism in deep‐water environments. This is reflected by a high variability of the first principal component in hemipelagic deposits. The stacked principal component variability of these deposits evidences that the contourite drift and the adjacent contourite channel were influenced by the interrelation of hemipelagic, gravitational and bottom current induced depositional processes. This interrelation questions the paradigm that a drift is made up solely of muddy sediments. The interrelation of sedimentary processes is a consequence of the precession‐driven changes in the intensity of the Mediterranean Outflow Water related to Mediterranean climate variability, which are punctuated by millennial‐scale variability. Associated vertical and lateral shifts of the Mediterranean Outflow Water, and therefore of its interface with the East North Atlantic Central Water, controlled sediment input and favoured turbulent sediment transport in the middle slope. During the interglacial precession maxima/insolation minima, a more vigorous upper core of the Mediterranean Outflow Water and the enhanced impact of the East North Atlantic Central Water – Mediterranean Outflow Water interface allowed for the development of the sandier contourite deposits.",
    url = "https://doi.org/10.1111/sed.12813",
    doi = "10.1111/sed.12813",
    openalex = "W3094434723",
    references = "doi101016jgloplacha201508015, doi103390geosciences10020068"
}

The distinction between turbidites, contourites and hemipelagites in modern and ancient deep-water systems has long been a matter of controversy. This is partly because the processes themselves show a degree of overlap as part of a continuum, so that the deposit characteristics also overlap. In addition, the three facies types commonly occur within interbedded sequences of continental margin deposits. The nature of these end-member processes and their physical parameters are becoming much better known and are summarised here briefly. Good progress has also been made over the past decade in recognising differences between end-member facies in terms of their sedimentary structures, facies sequences, ichnofacies, sediment textures, composition and microfabric. These characteristics are summarised here in terms of standard facies models and the variations from these models that are typically encountered in natural systems. Nevertheless, it must be acknowledged that clear distinction is not always possible on the basis of sedimentary characteristics alone, and that uncertainties should be highlighted in any interpretation. A three-scale approach to distinction for all deep-water facies types should be attempted wherever possible, including large-scale (oceanographic and tectonic setting), regional-scale (architecture and association) and small-scale (sediment facies) observations.

@article{doi103390geosciences10020068,
    author = "Stow, Dorrik A. V. and Smillie, Zeinab",
    title = "Distinguishing between Deep-Water Sediment Facies: Turbidites, Contourites and Hemipelagites",
    year = "2020",
    journal = "Geosciences",
    abstract = "The distinction between turbidites, contourites and hemipelagites in modern and ancient deep-water systems has long been a matter of controversy. This is partly because the processes themselves show a degree of overlap as part of a continuum, so that the deposit characteristics also overlap. In addition, the three facies types commonly occur within interbedded sequences of continental margin deposits. The nature of these end-member processes and their physical parameters are becoming much better known and are summarised here briefly. Good progress has also been made over the past decade in recognising differences between end-member facies in terms of their sedimentary structures, facies sequences, ichnofacies, sediment textures, composition and microfabric. These characteristics are summarised here in terms of standard facies models and the variations from these models that are typically encountered in natural systems. Nevertheless, it must be acknowledged that clear distinction is not always possible on the basis of sedimentary characteristics alone, and that uncertainties should be highlighted in any interpretation. A three-scale approach to distinction for all deep-water facies types should be attempted wherever possible, including large-scale (oceanographic and tectonic setting), regional-scale (architecture and association) and small-scale (sediment facies) observations.",
    url = "https://doi.org/10.3390/geosciences10020068",
    doi = "10.3390/geosciences10020068",
    openalex = "W3006008006",
    references = "doi1010079783642684234, doi1010160037073880900524, doi101016jgloenvcha201605009, doi101016jmargeo201403011, doi101016jmarpetgeo200301003, doi101016s0025322799000687, doi10102994pa03039, doi101086625710, doi101111j136530911995tb00395x, doi101111j13653091201201353x, doi101306212f7f312b2411d78648000102c1865d"
}

@article{doi101016jearscirev2021103531,
    author = "Fisher, William L. and Galloway, William E. and Steel, Ronald J. and Olariu, Cornel and Kerans, Charles and Mohrig, David",
    title = "Deep-water depositional systems supplied by shelf-incising submarine canyons: Recognition and significance in the geologic record",
    year = "2021",
    journal = "Earth-Science Reviews",
    url = "https://doi.org/10.1016/j.earscirev.2021.103531",
    doi = "10.1016/j.earscirev.2021.103531",
    openalex = "W3124143180",
    references = "doi101016003707389290052s, doi101016jearscirev200810003, doi101016jmarpetgeo201704008, doi10102997eo00356, doi101038s41598018246306, doi1013060c9b2907171011d78645000102c1865d, doi10130610210505018, doi101306111302730367, doi1013065d25c2d316c111d78645000102c1865d, doi101306703c9af5170711d78645000102c1865d, doi101306bdff8876171811d78645000102c1865d, doi101306m26490c6, doi102110pec88010039, doi102110pec88010125, kolla1990lowstand, openalexw106150921, paine1968stratigraphy"
}

Abstract Turbidites have been regarded as an important sedimentary infilling component in both oceans and lakes, but limited studies have been performed on the mechanisms governing the initiation and development of lacustrine turbidite systems. The present study offers unique insight into the controls and potential extent of ancient lacustrine turbidite systems by an investigation of the Triassic Ordos Lake, where a large turbidite system had been traced across >25 653 km 2. This article shows by comparison that the Triassic Ordos Lake turbidite system is larger than all known modern and ancient lacustrine counterparts. The exceptionally large intracontinental sag basin provided a relatively unconfined environment for the development of the turbidite system, explaining its vast extent. Extraordinary flood events formed during the Carnian Pluvial Episode facilitated continuous sediment supply into the turbidite system, supporting its accumulation. Lacustrine flood‐related turbidity currents travelled as sediment‐laden turbulent flows, showing an increase in the proportion of suspended‐load deposits and a decrease in the proportion of bed‐load deposits downstream from the river mouth. Five architectural elements have been revealed, reflecting a distinctive assemblage of erosional bedforms and depositional bedforms in channel‐lobe systems, and their recognition criteria were established. This study changes the traditional understanding of lacustrine turbidite systems, generally interpreted as having smaller sizes, and demonstrates likewise in the lacustrine realm, that extreme flood events can generate a world‐class deep‐water turbidite system, which can even be comparable with its submarine counterparts. This study also confirms that the combination of low‐gradient slopes and a long‐lived, mixed‐load, prograding fluvial feeder system can produce exceptionally large‐scale deep‐lake flood‐related turbidites. Furthermore, it has implications for the prediction of facies and reservoir quality in ancient lacustrine turbidite systems.

@article{doi101111sed12891,
    author = "Chen, Peng and Xian, Benzhong and Li, Meijun and Liang, Xiaowei and Wu, Qianran and Zhang, Wenmiao and Wang, Junhui and Wang, Zhen and Liu, Jianping",
    title = "A giant lacustrine flood‐related turbidite system in the Triassic Ordos Basin, China: Sedimentary processes and depositional architecture",
    year = "2021",
    journal = "Sedimentology",
    abstract = "Abstract Turbidites have been regarded as an important sedimentary infilling component in both oceans and lakes, but limited studies have been performed on the mechanisms governing the initiation and development of lacustrine turbidite systems. The present study offers unique insight into the controls and potential extent of ancient lacustrine turbidite systems by an investigation of the Triassic Ordos Lake, where a large turbidite system had been traced across >25 653 km 2. This article shows by comparison that the Triassic Ordos Lake turbidite system is larger than all known modern and ancient lacustrine counterparts. The exceptionally large intracontinental sag basin provided a relatively unconfined environment for the development of the turbidite system, explaining its vast extent. Extraordinary flood events formed during the Carnian Pluvial Episode facilitated continuous sediment supply into the turbidite system, supporting its accumulation. Lacustrine flood‐related turbidity currents travelled as sediment‐laden turbulent flows, showing an increase in the proportion of suspended‐load deposits and a decrease in the proportion of bed‐load deposits downstream from the river mouth. Five architectural elements have been revealed, reflecting a distinctive assemblage of erosional bedforms and depositional bedforms in channel‐lobe systems, and their recognition criteria were established. This study changes the traditional understanding of lacustrine turbidite systems, generally interpreted as having smaller sizes, and demonstrates likewise in the lacustrine realm, that extreme flood events can generate a world‐class deep‐water turbidite system, which can even be comparable with its submarine counterparts. This study also confirms that the combination of low‐gradient slopes and a long‐lived, mixed‐load, prograding fluvial feeder system can produce exceptionally large‐scale deep‐lake flood‐related turbidites. Furthermore, it has implications for the prediction of facies and reservoir quality in ancient lacustrine turbidite systems.",
    url = "https://doi.org/10.1111/sed.12891",
    doi = "10.1111/sed.12891",
    openalex = "W3158573202",
    references = "doi101016jsedgeo201603008, doi101126sciadvaba0099"
}

ABSTRACT Deposits of sediment gravity flows in the Aberystwyth Grits Group (Silurian, west Wales, United Kingdom) display evidence that sole marks are suitable for reconstructing depositional processes and environments in deep-marine sedimentary successions. Based on drone imagery, 3D laser scanning, high-resolution sedimentary logging, and detailed descriptions of sole marks, an outcrop 1600 m long between the villages of Aberarth and Llannon was subdivided into seven lithological units, representing: a) mudstone-poor, coarse-grained and thick-bedded submarine channel fills, dominated by the deposits of erosive high-density turbidity currents with flute marks; b) mudstone-rich levee deposits with thin-bedded, fine-grained sandstones formed by low-density turbidity currents that scoured the bed to form flute marks; c) channel–lobe transition-zone deposits, dominated by thick beds, formed by weakly erosive, coarse-grained hybrid events, with pronounced mudstone-rich or sandstone-dominated debritic divisions and groove marks below basal turbiditic divisions, and with subordinate amounts of turbidites and debris-flow deposits; d) tabular, medium- to thick-bedded turbiditic sandstones with flute marks and mixed sandstone–mudstone hybrid event beds mainly with groove marks, interpreted as submarine lobe-axis (or off-axis) deposits; and e) tabular, thin- to medium-bedded, fine-grained, mainly turbiditic sandstones mostly with flute marks, formed in a lobe-fringe environment. Both lobe environments also comprised turbidites with low-amplitude bed waves and large ripples, which are interpreted to represent transient-turbulent flows. The strong relationship between flute marks and turbidites agrees with earlier predictions that turbulent shear flows are essential for the formation of flute marks. Moreover, the observation as part of this study that debris-flow deposits are exclusively associated with groove marks signifies that clay-charged, laminar flows are carriers for tools that are in continuous contact with the bed. A new process model for hybrid event beds, informed by the dominance of tool marks, in particular grooves, below the basal sand division (H1 division of Haughton et al. 2009) and by the rapid change from turbidites in the channel to hybrid event beds in the channel–lobe transition zone, is proposed. This model incorporates profound erosion of clay in the channel by the head of a high-density turbidity current and subsequent transformation of the head into a debris flow following rapid lateral flow expansion at the mouth of the channel. This debris flow forms the groove marks below the H1 division in hybrid event beds. A temporal increase in cohesivity in the body of the hybrid event is used to explain the generation of the H1, H2, and H3 divisions (sensuHaughton et al. 2009) on top of the groove surfaces, involving a combination of longitudinal segregation of bedload and vertical segregation of suspension load. This study thus demonstrates that sole marks can be an integral part of sedimentological studies at different scales, well beyond their traditional use as indicators of paleoflow direction or orientation.

@article{doi102110jsr2020104,
    author = "Baas, Jaco H. and Tracey, Niall D. and Peakall, Jeff",
    title = "Sole marks reveal deep-marine depositional process and environment: Implications for flow transformation and hybrid-event-bed models",
    year = "2021",
    journal = "Journal of Sedimentary Research",
    abstract = "ABSTRACT Deposits of sediment gravity flows in the Aberystwyth Grits Group (Silurian, west Wales, United Kingdom) display evidence that sole marks are suitable for reconstructing depositional processes and environments in deep-marine sedimentary successions. Based on drone imagery, 3D laser scanning, high-resolution sedimentary logging, and detailed descriptions of sole marks, an outcrop 1600 m long between the villages of Aberarth and Llannon was subdivided into seven lithological units, representing: a) mudstone-poor, coarse-grained and thick-bedded submarine channel fills, dominated by the deposits of erosive high-density turbidity currents with flute marks; b) mudstone-rich levee deposits with thin-bedded, fine-grained sandstones formed by low-density turbidity currents that scoured the bed to form flute marks; c) channel–lobe transition-zone deposits, dominated by thick beds, formed by weakly erosive, coarse-grained hybrid events, with pronounced mudstone-rich or sandstone-dominated debritic divisions and groove marks below basal turbiditic divisions, and with subordinate amounts of turbidites and debris-flow deposits; d) tabular, medium- to thick-bedded turbiditic sandstones with flute marks and mixed sandstone–mudstone hybrid event beds mainly with groove marks, interpreted as submarine lobe-axis (or off-axis) deposits; and e) tabular, thin- to medium-bedded, fine-grained, mainly turbiditic sandstones mostly with flute marks, formed in a lobe-fringe environment. Both lobe environments also comprised turbidites with low-amplitude bed waves and large ripples, which are interpreted to represent transient-turbulent flows. The strong relationship between flute marks and turbidites agrees with earlier predictions that turbulent shear flows are essential for the formation of flute marks. Moreover, the observation as part of this study that debris-flow deposits are exclusively associated with groove marks signifies that clay-charged, laminar flows are carriers for tools that are in continuous contact with the bed. A new process model for hybrid event beds, informed by the dominance of tool marks, in particular grooves, below the basal sand division (H1 division of Haughton et al. 2009) and by the rapid change from turbidites in the channel to hybrid event beds in the channel–lobe transition zone, is proposed. This model incorporates profound erosion of clay in the channel by the head of a high-density turbidity current and subsequent transformation of the head into a debris flow following rapid lateral flow expansion at the mouth of the channel. This debris flow forms the groove marks below the H1 division in hybrid event beds. A temporal increase in cohesivity in the body of the hybrid event is used to explain the generation of the H1, H2, and H3 divisions (sensuHaughton et al. 2009) on top of the groove surfaces, involving a combination of longitudinal segregation of bedload and vertical segregation of suspension load. This study thus demonstrates that sole marks can be an integral part of sedimentological studies at different scales, well beyond their traditional use as indicators of paleoflow direction or orientation.",
    url = "https://doi.org/10.2110/jsr.2020.104",
    doi = "10.2110/jsr.2020.104",
    openalex = "W3184323091",
    references = "doi101111sed12376"
}

The deep-marine environment is a complex setting in which numerous processes —settling of pelagic and hemipelagic particles in the water column, sediment gravity flows (downslope density currents; turbid flows), and bottom currents— determine sediment deposition, hence a variety of facies including pelagites/hemipelagites, contourites, turbidites and hyperpycnites. Characterization and differentiation among deep-sea facies is a challenge, and numerous features may be highlighted to this end: sedimentary structures, geochemical data, micropaleontological information, etc. Ichnological information has become a valuable, yet in some cases controversial, proxy, being in most of cases understudied. This paper gathers the existing ichnological information regarding the most frequent deep-sea facies —from those in which ichnological analyses are numerous and detailed (e.g. pelagites/hemipelagites and turbidites), to those for which ichnological information is lacking or imprecise (hyperpycnites and contourites). This review analyses palaeoenvironmental (i.e., ecological and depositional) conditions associated with deep-sea sedimentary processes, influence of these changes on the tracemaker community, and associated ichnological properties. A detailed characterization of trace fossil assemblages, ichnofabrics and ichnofacies is presented. Special attention is paid to variations in trace fossil features, approached through sedimentary facies models and the outcrop/core scale. Similarities and differences among deep-sea facies are underlined to facilitate differentiation. Pelagic/hemipelagic sediments are completely bioturbated, showing biodeformational structures and trace fossils, being characterized by composite ichnofabrics. The trace fossil assemblage of muddy pelagites and hemipelagites is mainly assigned to the Zoophycos ichnofacies, and locally to the distal expression of the Cruziana ichnofacies. Turbidites are colonized mostly from the top, determining an uppermost part that is entirely bioturbated, the spotty layer; below it lies the elite layer, characterized by deep-tier trace fossils. Turbidite beds pertain to two different groups of burrows, either “pre-depositional”, mainly graphogliptids, or “post-depositional” traces. Turbidite deposits are mostly characterized by the Nereites ichnofacies, with differentiation of three ichnosubfacies according to the different parts of the turbiditic systems and the associated palaeoenvironmental conditions. There are no major differences in the trace fossil content of the hyperpycnite facies and the classical post-depositional turbidite, nor in the pelagic/hemipelagic sediments, except for a lower ichnodiversity in the hyperpycnites. Trace fossil assemblages of distal hyperpycnites are mainly assigned to the Nereites ichnofacies, while graphogliptids are scarce or absent. Ichnological features vary within contourites, largely related to palaeoenvironmental conditions, depositional setting, and type of contourite. Ichnodiversity and abundance can be high, especially for mud-silty contourites. The ichnological features of mud-silty contourites are similar to those of the pelagic/hemipelagic sediments (the tiering structure probably being more complex in pelagic/hemipelagic) or to the upper part of the muddy turbidites (contourites probably being more continuously bioturbated). No single archetypal ichnofacies would characterize contourites, mainly assigned to the Zoophycos and Cruziana ichnofacies.

@article{doi101016jearscirev2022104014,
    author = "Rodrı́guez-Tovar, Francisco J.",
    title = "Ichnological analysis: A tool to characterize deep-marine processes and sediments",
    year = "2022",
    journal = "Earth-Science Reviews",
    abstract = "The deep-marine environment is a complex setting in which numerous processes —settling of pelagic and hemipelagic particles in the water column, sediment gravity flows (downslope density currents; turbid flows), and bottom currents— determine sediment deposition, hence a variety of facies including pelagites/hemipelagites, contourites, turbidites and hyperpycnites. Characterization and differentiation among deep-sea facies is a challenge, and numerous features may be highlighted to this end: sedimentary structures, geochemical data, micropaleontological information, etc. Ichnological information has become a valuable, yet in some cases controversial, proxy, being in most of cases understudied. This paper gathers the existing ichnological information regarding the most frequent deep-sea facies —from those in which ichnological analyses are numerous and detailed (e.g. pelagites/hemipelagites and turbidites), to those for which ichnological information is lacking or imprecise (hyperpycnites and contourites). This review analyses palaeoenvironmental (i.e., ecological and depositional) conditions associated with deep-sea sedimentary processes, influence of these changes on the tracemaker community, and associated ichnological properties. A detailed characterization of trace fossil assemblages, ichnofabrics and ichnofacies is presented. Special attention is paid to variations in trace fossil features, approached through sedimentary facies models and the outcrop/core scale. Similarities and differences among deep-sea facies are underlined to facilitate differentiation. Pelagic/hemipelagic sediments are completely bioturbated, showing biodeformational structures and trace fossils, being characterized by composite ichnofabrics. The trace fossil assemblage of muddy pelagites and hemipelagites is mainly assigned to the Zoophycos ichnofacies, and locally to the distal expression of the Cruziana ichnofacies. Turbidites are colonized mostly from the top, determining an uppermost part that is entirely bioturbated, the spotty layer; below it lies the elite layer, characterized by deep-tier trace fossils. Turbidite beds pertain to two different groups of burrows, either “pre-depositional”, mainly graphogliptids, or “post-depositional” traces. Turbidite deposits are mostly characterized by the Nereites ichnofacies, with differentiation of three ichnosubfacies according to the different parts of the turbiditic systems and the associated palaeoenvironmental conditions. There are no major differences in the trace fossil content of the hyperpycnite facies and the classical post-depositional turbidite, nor in the pelagic/hemipelagic sediments, except for a lower ichnodiversity in the hyperpycnites. Trace fossil assemblages of distal hyperpycnites are mainly assigned to the Nereites ichnofacies, while graphogliptids are scarce or absent. Ichnological features vary within contourites, largely related to palaeoenvironmental conditions, depositional setting, and type of contourite. Ichnodiversity and abundance can be high, especially for mud-silty contourites. The ichnological features of mud-silty contourites are similar to those of the pelagic/hemipelagic sediments (the tiering structure probably being more complex in pelagic/hemipelagic) or to the upper part of the muddy turbidites (contourites probably being more continuously bioturbated). No single archetypal ichnofacies would characterize contourites, mainly assigned to the Zoophycos and Cruziana ichnofacies.",
    url = "https://doi.org/10.1016/j.earscirev.2022.104014",
    doi = "10.1016/j.earscirev.2022.104014",
    openalex = "W4220781689",
    references = "doi101016jmarpetgeo201402016, doi101016jsedgeo201603008, doi103390geosciences10020068"
}

Interactions between along-slope bottom currents and down-slope turbidity flows can create a myriad of features and deposits. Despite numerous efforts to differentiate contourites from turbidites and mixed features, reliable diagnostic criteria are still lacking from the stratigraphic and sedimentological viewpoints. The main aim of this study is to develop criteria to differentiate mixed, along-slope-, and down-slope-generated elements from other deep-water deposits across bathymetric, seismic and sediment core data. Mixed (turbidite-contourite) systems can be placed in three main groups based on their location, dimensions, elongation, lateral migration, spatial and temporal variability: 1) turbidite-dominated mixed systems, 2) synchronous systems, and 3) contourite-dominated mixed systems. The persistence of bottom currents —in addition to their velocity, direction, and hydrodynamic fluctuations— is responsible for entraining and redistributing fine-grained particles, carried in suspension by coeval turbidity flows, and reworking previously deposited sediments. Changes in turbidity current velocity, frequency, and duration condition the provision of sediments and development of turbidites along mixed systems. Several preliminary models are also being proposed in this study, in order to enhance our understanding of the lateral and vertical distribution of mixed systems across the sedimentary record. Interactions between along- and down-slope processes may be synchronous, asynchronous or passive. Synchronous interactions typically occur within the same physiographic setting and the two processes interact coevally in space and time. Asynchronous interactions are also common across the modern and ancient sedimentary records, as bottom currents sweep across the deep-water environments during breaks of the turbidity flows. Passive interactions occur along the distal margins of mixed systems, or when the two processes occur near each other but do not cross over in time. Further controlling factors are held to be influential in the evolution of mixed systems at the short- to long-term; varying degrees of confinement, sediment supply or climatic fluctuations can generate cyclic stacking patterns and affect their overall dimensions. Accordingly, mixed systems feature more complex geometries than previously believed, as interactions may generate new secondary processes and features. Such systems form potential plays and may become future targets for energy geosciences and other research fields.

@article{doi101016jearscirev2022104030,
    author = "Rodrigues, Sara and Hernández-Molina, F.J. and Fonnesu, Marco and Miramontes, Elda and Rebesco, Michele and Campbell, D C",
    title = "A new classification system for mixed (turbidite-contourite) depositional systems: Examples, conceptual models and diagnostic criteria for modern and ancient records",
    year = "2022",
    journal = "Earth-Science Reviews",
    abstract = "Interactions between along-slope bottom currents and down-slope turbidity flows can create a myriad of features and deposits. Despite numerous efforts to differentiate contourites from turbidites and mixed features, reliable diagnostic criteria are still lacking from the stratigraphic and sedimentological viewpoints. The main aim of this study is to develop criteria to differentiate mixed, along-slope-, and down-slope-generated elements from other deep-water deposits across bathymetric, seismic and sediment core data. Mixed (turbidite-contourite) systems can be placed in three main groups based on their location, dimensions, elongation, lateral migration, spatial and temporal variability: 1) turbidite-dominated mixed systems, 2) synchronous systems, and 3) contourite-dominated mixed systems. The persistence of bottom currents —in addition to their velocity, direction, and hydrodynamic fluctuations— is responsible for entraining and redistributing fine-grained particles, carried in suspension by coeval turbidity flows, and reworking previously deposited sediments. Changes in turbidity current velocity, frequency, and duration condition the provision of sediments and development of turbidites along mixed systems. Several preliminary models are also being proposed in this study, in order to enhance our understanding of the lateral and vertical distribution of mixed systems across the sedimentary record. Interactions between along- and down-slope processes may be synchronous, asynchronous or passive. Synchronous interactions typically occur within the same physiographic setting and the two processes interact coevally in space and time. Asynchronous interactions are also common across the modern and ancient sedimentary records, as bottom currents sweep across the deep-water environments during breaks of the turbidity flows. Passive interactions occur along the distal margins of mixed systems, or when the two processes occur near each other but do not cross over in time. Further controlling factors are held to be influential in the evolution of mixed systems at the short- to long-term; varying degrees of confinement, sediment supply or climatic fluctuations can generate cyclic stacking patterns and affect their overall dimensions. Accordingly, mixed systems feature more complex geometries than previously believed, as interactions may generate new secondary processes and features. Such systems form potential plays and may become future targets for energy geosciences and other research fields.",
    url = "https://doi.org/10.1016/j.earscirev.2022.104030",
    doi = "10.1016/j.earscirev.2022.104030",
    openalex = "W4224871650",
    references = "doi101016jmarpetgeo201506007, doi101016jmarpetgeo201812023, doi101016s187638041730023x, doi101111sed12772, doi101130b309961, doi102110jsr202036, doi103390geosciences10020068"
}