Dolomite

@article{berry1979house,
    author = "Berry, R. J. and Jackson, W. B.",
    title = "House Mice on Enewetak Atoll",
    year = "1979",
    journal = "Journal of Mammalogy",
    url = "https://doi.org/10.2307/1379782",
    doi = "10.2307/1379782",
    number = "1",
    pages = "222-225",
    volume = "60"
}

Currents at Enewetak Atoll, Marshall Islands, were measured on the reef margins, in the channels, and in the lagoon. Lagoon circulation is dominated by wind‐driven downwind surface flow and an upwind middepth return flow. This wind‐driven flow has the characteristics of an Ekman spiral in an enclosed sea. Lagoon flushing is accomplished primarily by surf‐driven water input over the windward (eastern) reefs and southerly drift out the South Channel. Mean water residence time is 1 month, while water entering the northern portion of the atoll takes about 4 months to exit.

@article{atkinson1981circulation,
    author = "Atkinson, M. and Smith, S. V. and Stroup, E. D.",
    title = "Circulation in Enewetak Atoll lagoon1",
    year = "1981",
    journal = "Limnology and Oceanography",
    abstract = "Currents at Enewetak Atoll, Marshall Islands, were measured on the reef margins, in the channels, and in the lagoon. Lagoon circulation is dominated by wind‐driven downwind surface flow and an upwind middepth return flow. This wind‐driven flow has the characteristics of an Ekman spiral in an enclosed sea. Lagoon flushing is accomplished primarily by surf‐driven water input over the windward (eastern) reefs and southerly drift out the South Channel. Mean water residence time is 1 month, while water entering the northern portion of the atoll takes about 4 months to exit.",
    url = "https://doi.org/10.4319/lo.1981.26.6.1074",
    doi = "10.4319/lo.1981.26.6.1074",
    number = "6",
    pages = "1074-1083",
    volume = "26"
}

Dolomite is present 1,250–1,400 m below sea level in Eocene strata of Enewetak Atoll. Petrographically, the deep Enewetak dolomite postdates brittle compaction of rigid grains in the host Eocene strata. The 87 Sr/ 86 Sr ratio of these dolomites (0.70865–0.70901) indicates that they formed at one or more times between the middle Miocene and the present. Since the top of the lower Miocene is more than 900 m above the deep dolomitic interval, the dolomite must have formed at a minimum burial depth of 900 m. Stable-oxygen-isotope determinations suggest dolomite precipitation from cold marine water. Lower Miocene and Eocene carbonate strata on the atoll are apparently in open communication with cold, modern ocean water, suggesting that those same strata were in open communication with ocean water during dolomitization. At a depth of about 1,000 m, modern Pacific Ocean water becomes undersaturated with respect to calcite but is still supersaturated with respect to dolomite. Therefore, it is proposed that the deep Enewetak dolomite precipitated from cold, deep ocean water (undersaturated with respect to calcite) at a burial depth of more than 900 m.

@article{doi10113000917613198412217pagcot20co2,
    author = "Saller, Arthur",
    title = "Petrologic and geochemical constraints on the origin of subsurface dolomite, Enewetak Atoll: An example of dolomitization by normal seawater",
    year = "1984",
    journal = "Geology",
    abstract = "Dolomite is present 1,250–1,400 m below sea level in Eocene strata of Enewetak Atoll. Petrographically, the deep Enewetak dolomite postdates brittle compaction of rigid grains in the host Eocene strata. The 87 Sr/ 86 Sr ratio of these dolomites (0.70865–0.70901) indicates that they formed at one or more times between the middle Miocene and the present. Since the top of the lower Miocene is more than 900 m above the deep dolomitic interval, the dolomite must have formed at a minimum burial depth of 900 m. Stable-oxygen-isotope determinations suggest dolomite precipitation from cold marine water. Lower Miocene and Eocene carbonate strata on the atoll are apparently in open communication with cold, modern ocean water, suggesting that those same strata were in open communication with ocean water during dolomitization. At a depth of about 1,000 m, modern Pacific Ocean water becomes undersaturated with respect to calcite but is still supersaturated with respect to dolomite. Therefore, it is proposed that the deep Enewetak dolomite precipitated from cold, deep ocean water (undersaturated with respect to calcite) at a burial depth of more than 900 m.",
    url = "https://doi.org/10.1130/0091-7613(1984)12<217:pagcot>2.0.co;2",
    doi = "10.1130/0091-7613(1984)12<217:pagcot>2.0.co;2",
    openalex = "W2080128143"
}

@article{saller1984petrologic,
    author = "Saller, Arthur H.",
    title = "Petrologic and geochemical constraints on the origin of subsurface dolomite, Enewetak Atoll: An example of dolomitization by normal seawater",
    year = "1984",
    journal = "Geology",
    url = "https://doi.org/10.1130/0091-7613(1984)12<217:pagcot>2.0.co;2",
    doi = "10.1130/0091-7613(1984)12<217:pagcot>2.0.co;2",
    number = "4",
    pages = "217",
    volume = "12"
}

@misc{saller1984petrologic1,
    author = "Saller, A",
    title = "Petrologic and geochemical constraints on the origin of subsurface dolomite, Enewetak Atoll",
    year = "1984",
    howpublished = "Geology, v. 12, p. 217-220",
    note = "talkorigins\_source = {true}; raw\_reference = {Saller, A., 1984, Petrologic and geochemical constraints on the origin of subsurface dolomite, Enewetak Atoll: Geology, v. 12, p. 217-220.}"
}

Most dolomite forms as a calcium-rich and/or poorly ordered metastable phase when seawater is actively circulated through carbonate sediments. Modification of seawater by evaporation, mixing with meteoric water, and/or sulfate reduction promotes dolomitization, but is not necessary. The extensive circulation which is necessary for massive dolomitization can be caused by density or elevation head, or by convection induced by geothermal heat. Progressive stabilization of metastable dolomite (replacement by more stable phases), especially at slightly elevated temperatures in the subsurface, results in crystal enlargement and chemical modification which masks original properties.

@article{doi10540800221368332112,
    author = "Land, Lynton S.",
    title = "The Origin of Massive Dolomite",
    year = "1985",
    journal = "Journal of Geological Education",
    abstract = "Most dolomite forms as a calcium-rich and/or poorly ordered metastable phase when seawater is actively circulated through carbonate sediments. Modification of seawater by evaporation, mixing with meteoric water, and/or sulfate reduction promotes dolomitization, but is not necessary. The extensive circulation which is necessary for massive dolomitization can be caused by density or elevation head, or by convection induced by geothermal heat. Progressive stabilization of metastable dolomite (replacement by more stable phases), especially at slightly elevated temperatures in the subsurface, results in crystal enlargement and chemical modification which masks original properties.",
    url = "https://doi.org/10.5408/0022-1368-33.2.112",
    doi = "10.5408/0022-1368-33.2.112",
    openalex = "W2517847674"
}

@article{goldstein1996dolomite,
    author = "Goldstein, Robert H.",
    title = "Dolomite from Reflux of Moderate Salinity Brine, Enewetak Atoll: ABSTRACT",
    year = "1996",
    journal = "AAPG Bulletin",
    url = "https://doi.org/10.1306/522b2c4b-1727-11d7-8645000102c1865d",
    doi = "10.1306/522b2c4b-1727-11d7-8645000102c1865d",
    volume = "80"
}

@incollection{buddemeier2004hydrogeology,
    author = "Buddemeier, Robert W. and Oberdorfer, June A.",
    title = "Hydrogeology of Enewetak Atoll",
    year = "2004",
    booktitle = "Developments in Sedimentology",
    url = "https://doi.org/10.1016/s0070-4571(04)80044-x",
    doi = "10.1016/s0070-4571(04)80044-x",
    pages = "667-692"
}

Abstract Dolostones in the Cayman Formation on Grand Cayman and Cayman Brac, which are the product of two and possibly three phases of dolomitization, are formed of very small (The recognition that individual dolomite crystals, irrespective of their size, may be architecturally heterogeneous carries important implications for dolomite genesis. Many interpretations of finely crystalline dolostones, for example, have tacitly assumed that they formed through one phase of dolomitization. In the Cayman Formation, however, dolomite crystals as small as 10 μm are characterized by internal heterogeneities that record their development through multiple, time-separated growth phases. Any model developed to explain dolomitization must take this into account. The interpretation of chemical data, for example, must consider the multiple-stage development of the dolostones that is evident from their internal zoning and discontinuities.

@article{doi102110jsr2005014,
    author = "Jones, Brian",
    title = "Dolomite Crystal Architecture: Genetic Implications for the Origin of the Tertiary Dolostones of the Cayman Islands",
    year = "2005",
    journal = "Journal of Sedimentary Research",
    abstract = "Abstract Dolostones in the Cayman Formation on Grand Cayman and Cayman Brac, which are the product of two and possibly three phases of dolomitization, are formed of very small (The recognition that individual dolomite crystals, irrespective of their size, may be architecturally heterogeneous carries important implications for dolomite genesis. Many interpretations of finely crystalline dolostones, for example, have tacitly assumed that they formed through one phase of dolomitization. In the Cayman Formation, however, dolomite crystals as small as 10 μm are characterized by internal heterogeneities that record their development through multiple, time-separated growth phases. Any model developed to explain dolomitization must take this into account. The interpretation of chemical data, for example, must consider the multiple-stage development of the dolostones that is evident from their internal zoning and discontinuities.",
    url = "https://doi.org/10.2110/jsr.2005.014",
    doi = "10.2110/jsr.2005.014",
    openalex = "W2001388672",
    references = "goldstein1996dolomite"
}

Abstract In the past decade, more than 20 new natural gas fields have been discovered in laterally discontinuous dolomites of the Upper Ordovician Black River Group in south-central New York. The dolomites form around basement-rooted wrench faults that are detectable on seismic data. Most fields occur in and around elongate fault-bounded structural lows interpreted to be negative flower structures. Away from these faults, the formation is composed of impermeable limestone and forms the lateral seal for the reservoirs. In most cases, the faults die out within the overlying Trenton Limestone and Utica Shale. Most porosity occurs in saddle dolomite-coated vugs, breccias, and fractured zones. Matrix porosity is uncommon in the Black River cores described for this study. The patchy distribution around basement-rooted faults and geochemical and fluid-inclusion analyses supports a fault-related hydrothermal origin for the saddle and matrix dolomites. This play went for many years without detection because of its unconventional structural setting (i.e., structural lows versus highs). Using the appropriate integrated structural-stratigraphic-diagenetic model, more hydrothermal dolomite natural gas reservoirs are likely to be discovered in the Black River of New York and in carbonates around the world.

@article{doi10130604260605078,
    author = "Smith, Langhorne B.",
    title = "Origin and reservoir characteristics of Upper Ordovician Trenton–Black River hydrothermal dolomite reservoirs in New York",
    year = "2006",
    journal = "AAPG Bulletin",
    abstract = "Abstract In the past decade, more than 20 new natural gas fields have been discovered in laterally discontinuous dolomites of the Upper Ordovician Black River Group in south-central New York. The dolomites form around basement-rooted wrench faults that are detectable on seismic data. Most fields occur in and around elongate fault-bounded structural lows interpreted to be negative flower structures. Away from these faults, the formation is composed of impermeable limestone and forms the lateral seal for the reservoirs. In most cases, the faults die out within the overlying Trenton Limestone and Utica Shale. Most porosity occurs in saddle dolomite-coated vugs, breccias, and fractured zones. Matrix porosity is uncommon in the Black River cores described for this study. The patchy distribution around basement-rooted faults and geochemical and fluid-inclusion analyses supports a fault-related hydrothermal origin for the saddle and matrix dolomites. This play went for many years without detection because of its unconventional structural setting (i.e., structural lows versus highs). Using the appropriate integrated structural-stratigraphic-diagenetic model, more hydrothermal dolomite natural gas reservoirs are likely to be discovered in the Black River of New York and in carbonates around the world.",
    url = "https://doi.org/10.1306/04260605078",
    doi = "10.1306/04260605078",
    openalex = "W2010296282",
    references = "doi10130605220605164"
}

Abstract Structurally controlled hydrothermal dolomite (HTD) reservoir facies and associated productive leached limestones are major hydrocarbon producers in North America and are receiving increased exploration attention globally. They include multiple trends in the Ordovician (locally, Silurian and Devonian) of the Michigan, Appalachian, and other basins of eastern Canada and the United States, and in the Devonian and Mississippian of the Western Canada sedimentary basin. They also occur in Jurassic hosts along rifted Atlantic margins, in the Jurassic–Cretaceous of the Arabian Gulf region and elsewhere. Hydrothermal dolomitization is defined as dolomitization occurring under burial conditions, commonly at shallow depths, by fluids (typically very saline) with temperature and pressure (T and P) higher than the ambient T and P of the host formation. The latter commonly is limestone. Proof of a hydrothermal origin for HTD reservoir facies requires integration of burial-thermal history plots, fluid-inclusion temperature data, and constraints on timing of emplacement. Hydrothermal dolomite reservoir facies are part of a spectrum of hydrothermal mineral deposits that include sedimentary-exhalative lead-zinc ore bodies and HTD-hosted Mississippi Valley–type sulfide deposits. All three hydrothermal deposits show a strong structural control by extensional and/or strike-slip (wrench) faults, with fluid flow typically focused at transtensional and dilational structural sites and in the hanging wall. Transtensional sags above negative flower structures on wrench faults are favored drilling sites for HTD reservoir facies. Saddle dolomite in both replacive and void-filling modes is characteristic of HTD facies. For many reservoirs, matrix-replacive dolomite and saddle dolomite appear to have formed near-contemporaneously and from the same fluid and temperature conditions. The original host facies exerts a major influence on the lateral extent of dolomitization, resultant textures, pore type, and pore volume. Breccias, zebra fabrics, shear microfractures, and other rock characteristics record short-term shear stress and pore-fluid-pressure transients, particularly proximal to active faults. High-temperature hydrothermal pulses may alter kerogen in host limestones, a process designated “forced maturation.” Basement highs, underlying sandstone (and/or carbonate?) aquifers (probably overpressured), and overlying and internal shale seals and aquitards also may constrain or influence HTD emplacement. Although many questions and uncertainties remain, particularly in terms of Mg and brine source and mass balance, recognition and active exploration of the HTD play continues to expand. Increasing use of three-dimensional seismic imagery and seismic anomaly mapping, combined with horizontal drilling oblique to linear trends defined by structural sags, helps to reduce risk.

@article{doi10130605220605164,
    author = "Davies, Graham R. and Smith, Langhorne B.",
    title = "Structurally controlled hydrothermal dolomite reservoir facies: An overview",
    year = "2006",
    journal = "AAPG Bulletin",
    abstract = "Abstract Structurally controlled hydrothermal dolomite (HTD) reservoir facies and associated productive leached limestones are major hydrocarbon producers in North America and are receiving increased exploration attention globally. They include multiple trends in the Ordovician (locally, Silurian and Devonian) of the Michigan, Appalachian, and other basins of eastern Canada and the United States, and in the Devonian and Mississippian of the Western Canada sedimentary basin. They also occur in Jurassic hosts along rifted Atlantic margins, in the Jurassic–Cretaceous of the Arabian Gulf region and elsewhere. Hydrothermal dolomitization is defined as dolomitization occurring under burial conditions, commonly at shallow depths, by fluids (typically very saline) with temperature and pressure (T and P) higher than the ambient T and P of the host formation. The latter commonly is limestone. Proof of a hydrothermal origin for HTD reservoir facies requires integration of burial-thermal history plots, fluid-inclusion temperature data, and constraints on timing of emplacement. Hydrothermal dolomite reservoir facies are part of a spectrum of hydrothermal mineral deposits that include sedimentary-exhalative lead-zinc ore bodies and HTD-hosted Mississippi Valley–type sulfide deposits. All three hydrothermal deposits show a strong structural control by extensional and/or strike-slip (wrench) faults, with fluid flow typically focused at transtensional and dilational structural sites and in the hanging wall. Transtensional sags above negative flower structures on wrench faults are favored drilling sites for HTD reservoir facies. Saddle dolomite in both replacive and void-filling modes is characteristic of HTD facies. For many reservoirs, matrix-replacive dolomite and saddle dolomite appear to have formed near-contemporaneously and from the same fluid and temperature conditions. The original host facies exerts a major influence on the lateral extent of dolomitization, resultant textures, pore type, and pore volume. Breccias, zebra fabrics, shear microfractures, and other rock characteristics record short-term shear stress and pore-fluid-pressure transients, particularly proximal to active faults. High-temperature hydrothermal pulses may alter kerogen in host limestones, a process designated “forced maturation.” Basement highs, underlying sandstone (and/or carbonate?) aquifers (probably overpressured), and overlying and internal shale seals and aquitards also may constrain or influence HTD emplacement. Although many questions and uncertainties remain, particularly in terms of Mg and brine source and mass balance, recognition and active exploration of the HTD play continues to expand. Increasing use of three-dimensional seismic imagery and seismic anomaly mapping, combined with horizontal drilling oblique to linear trends defined by structural sags, helps to reduce risk.",
    url = "https://doi.org/10.1306/05220605164",
    doi = "10.1306/05220605164",
    openalex = "W2119037023",
    references = "doi1010160191814186900210, doi1010160191814186900222, doi1011300016760619881001666ssf23co2, doi1011300016760619911030001oamolc23co2, doi1011300091761319861499fetfob20co2, doi1011300091761319880160551harffp23co2, doi101146annurevea17050189001041, doi101306212f7b9e2b2411d78648000102c1865d, doi101306212f8ad52b2411d78648000102c1865d, doi102475ajs3012112, openalexw2103810229"
}

@incollection{lee2006geochemicalpetrologic,
    author = "Lee, Cin-Ty Aeolus",
    title = "Geochemical/petrologic constraints on the origin of cratonic mantle",
    year = "2006",
    booktitle = "Geophysical Monograph Series",
    url = "https://doi.org/10.1029/164gm08",
    doi = "10.1029/164gm08",
    openalex = "W1589366413",
    pages = "89-114",
    references = "doi101007bf00371878, doi101007bf00373711, doi1010160012821x96001549, doi1010160016703784904150, doi101016004019519390295u, doi10102993rg01249, doi101093petrology253713, doi101093petrology293625, doi101093petrology3161353, doi101146annurevea16050188002551"
}

Abstract Beginning in the late 18th Century, the Dolomite Mountains in Northern Italy have been the location for major sedimentological developments, from the discovery of the mineral dolomite to the formulation of the coral‐reef hypothesis to explain the origin of the massive dolomite structures that define the splendid scenery of the region. Further, the Dolomite Mountains have inspired voluminous research into the origin of dolomite, questioning whether dolomite is a primary precipitate or a secondary replacement product. Recently, with the recognition that microbes can mediate dolomite precipitation, a new geomicrobiological approach, combining the study of modern natural environments with bacterial culture experiments, is now being used to calibrate or interpret microbial evidence derived from the dolomite rock record. This three‐pronged methodology applied to the study of dolomite formation holds great promise for future research into the ‘Dolomite Problem’ and provides a new impetus to revisit the Dolomite Mountains in the 21st Century.

@article{doi101111j13653091200801027x,
    author = "McKenzie, Judith A. and Vásconcelos, Crisógono",
    title = "Dolomite Mountains and the origin of the dolomite rock of which they mainly consist: historical developments and new perspectives",
    year = "2008",
    journal = "Sedimentology",
    abstract = "Abstract Beginning in the late 18th Century, the Dolomite Mountains in Northern Italy have been the location for major sedimentological developments, from the discovery of the mineral dolomite to the formulation of the coral‐reef hypothesis to explain the origin of the massive dolomite structures that define the splendid scenery of the region. Further, the Dolomite Mountains have inspired voluminous research into the origin of dolomite, questioning whether dolomite is a primary precipitate or a secondary replacement product. Recently, with the recognition that microbes can mediate dolomite precipitation, a new geomicrobiological approach, combining the study of modern natural environments with bacterial culture experiments, is now being used to calibrate or interpret microbial evidence derived from the dolomite rock record. This three‐pronged methodology applied to the study of dolomite formation holds great promise for future research into the ‘Dolomite Problem’ and provides a new impetus to revisit the Dolomite Mountains in the 21st Century.",
    url = "https://doi.org/10.1111/j.1365-3091.2008.01027.x",
    doi = "10.1111/j.1365-3091.2008.01027.x",
    openalex = "W1983191214",
    references = "doi101144gslsp20042350102"
}

Replacement dolomite in the Latemar carbonate buildup developed when limestone was infiltrated by reactive fluid. Minor-element, trace-element, and oxygen and carbon isotope compositions of dolomite and precursor limestone constrain the origin of the fluid and fundamental aspects of the flow. Inferred salinity (similar to seawater); temperature (45°–85°C); 87 Sr/ 86 Sr (0.7076–0.7079); Ca/Mg (6 mol fluid/cm 2 rock or (4–7) · 10 7 cm 3 fluid/cm 2 rock. Estimation of time-integrated flux leads to an internally consistent framework for the appropriate interpretation of the oxygen, strontium, and carbon isotope compositions of replacement dolomite. The oxygen and strontium isotope compositions reflect equilibration with dolomitizing fluid and provide a chemical fingerprint of the fluid. The carbon isotope composition of dolomite, however, was simply inherited directly from the precursor limestone in nearly all cases. A quantitative evaluation of the minor- and trace-element budget of dolomitization verifies that a fluid like modern diffuse effluent, but not unmodified seawater, could supply sufficient Fe, Mn, and Zn to enrich dolomite in these elements compared to limestone. If the flux of dolomitizing fluid was similar to that of modern diffuse effluent, ∼0.02 cm 3 /cm 2 · s, the duration of fluid flow and mineral-fluid reaction was short, ∼100 years. The total duration of dolomitization, however, could have been much longer if fluid flow was episodic, as in modern seafloor hydrothermal systems, depending on the time elapsed between episodes of flow. Conversion of limestone to dolomite likely occurred by a mechanism intermediate between the end-member cases of replacement at constant oxygen and carbon and replacement at constant volume.

@article{doi10247508200801,
    author = "Carmichael, Sarah K. and Ferry, John M.",
    title = "Formation of replacement dolomite in the Latemar carbonate buildup, Dolomites, northern Italy: Part 2. Origin of the dolomitizing fluid and the amount and duration of fluid flow",
    year = "2008",
    journal = "American Journal of Science",
    abstract = "Replacement dolomite in the Latemar carbonate buildup developed when limestone was infiltrated by reactive fluid. Minor-element, trace-element, and oxygen and carbon isotope compositions of dolomite and precursor limestone constrain the origin of the fluid and fundamental aspects of the flow. Inferred salinity (similar to seawater); temperature (45°–85°C); 87 Sr/ 86 Sr (0.7076–0.7079); Ca/Mg (6 mol fluid/cm 2 rock or (4–7) · 10 7 cm 3 fluid/cm 2 rock. Estimation of time-integrated flux leads to an internally consistent framework for the appropriate interpretation of the oxygen, strontium, and carbon isotope compositions of replacement dolomite. The oxygen and strontium isotope compositions reflect equilibration with dolomitizing fluid and provide a chemical fingerprint of the fluid. The carbon isotope composition of dolomite, however, was simply inherited directly from the precursor limestone in nearly all cases. A quantitative evaluation of the minor- and trace-element budget of dolomitization verifies that a fluid like modern diffuse effluent, but not unmodified seawater, could supply sufficient Fe, Mn, and Zn to enrich dolomite in these elements compared to limestone. If the flux of dolomitizing fluid was similar to that of modern diffuse effluent, ∼0.02 cm 3 /cm 2 · s, the duration of fluid flow and mineral-fluid reaction was short, ∼100 years. The total duration of dolomitization, however, could have been much longer if fluid flow was episodic, as in modern seafloor hydrothermal systems, depending on the time elapsed between episodes of flow. Conversion of limestone to dolomite likely occurred by a mechanism intermediate between the end-member cases of replacement at constant oxygen and carbon and replacement at constant volume.",
    url = "https://doi.org/10.2475/08.2008.01",
    doi = "10.2475/08.2008.01",
    openalex = "W2129035503",
    references = "doi101016009830049290029q, doi101016c20201040965, doi101016s0016703797001695, doi10103835059215, doi10106311671982, doi101111j15251314199800140x, doi101126science20343851073, doi10113000917613198210516vosstp20co2, openalexw1535539135, openalexw3139812027"
}

Integrated petrographic, geochemical, and fluid inclusion study of fracture mineralization and associated host rock in selected Mississippian and Devonian carbonates extending from southeastern Alberta to northwestern British Columbia, Canada, aims to quantify the type and nature of fluid precipitated saddle dolomite and late calcite cement and their origin. Petrographic and isotopic evidence from both the Devonian and Mississippian fracture-filling carbonates indicate the presence of a hydrothermal fluid source. The δ 18 O isotopic values for the Devonian saddle dolomite (−14.62‰ to −3.75‰ VPDB, average −11.12‰) combined with enriched 87 Sr/ 86 Sr isotopic ratios (0.70827–0.71599, average 0.71006) and higher homogenization temperatures (T h = 74–194.6 °C, average 126.8 °C) and salinity values (7.7–26.6 wt.% NaCl, average 16.2 wt.% NaCl) show significant differences from the Mississippian saddle dolomite, which is characterized by less negative δ 18 O isotopic values (−12.53‰ to −7.82‰ VPDB, average −9.14‰), less radiogenic 87 Sr/ 86 Sr isotopic ratios (0.70859–0.70943, average 0.70887), and lower homogenization temperatures (T h) and salinity values of fluid inclusions (87.6–214.2 °C, average 136.3 °C; 2.0–13.2 wt.% NaCl, average 9.6 wt.% NaCl). Later fracture- and vug-rimming blocky calcite cement records comparable or slightly lower values of δ 18 O (−16.31‰ to −4.08‰ VPDB, average −9.76‰) and 87 Sr/ 86 Sr (0.70784–0.709743, average 0.70868) and much lower salinity values (0–22.5 wt.% NaCl, average 2.86 wt.% NaCl) for samples mostly from the Mississippian age group. These results possibly suggest two different hydrothermal episodes related to early (Antler) and late (Laramide) tectonic events that affected the Western Canada Sedimentary Basin with possible compartmentalization of hydrothermal systems and their associated brines in the basin.

@article{doi101139cjes20180226,
    author = "Al‐Aasm, Ihsan S. and Mrad, Carole and Packard, Jeffery",
    title = "Fluid compartmentalization of Devonian and Mississippian dolostones, Western Canada Sedimentary Basin: petrologic and geochemical evidence from fracture mineralization",
    year = "2019",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "Integrated petrographic, geochemical, and fluid inclusion study of fracture mineralization and associated host rock in selected Mississippian and Devonian carbonates extending from southeastern Alberta to northwestern British Columbia, Canada, aims to quantify the type and nature of fluid precipitated saddle dolomite and late calcite cement and their origin. Petrographic and isotopic evidence from both the Devonian and Mississippian fracture-filling carbonates indicate the presence of a hydrothermal fluid source. The δ 18 O isotopic values for the Devonian saddle dolomite (−14.62‰ to −3.75‰ VPDB, average −11.12‰) combined with enriched 87 Sr/ 86 Sr isotopic ratios (0.70827–0.71599, average 0.71006) and higher homogenization temperatures (T h = 74–194.6 °C, average 126.8 °C) and salinity values (7.7–26.6 wt.\% NaCl, average 16.2 wt.\% NaCl) show significant differences from the Mississippian saddle dolomite, which is characterized by less negative δ 18 O isotopic values (−12.53‰ to −7.82‰ VPDB, average −9.14‰), less radiogenic 87 Sr/ 86 Sr isotopic ratios (0.70859–0.70943, average 0.70887), and lower homogenization temperatures (T h) and salinity values of fluid inclusions (87.6–214.2 °C, average 136.3 °C; 2.0–13.2 wt.\% NaCl, average 9.6 wt.\% NaCl). Later fracture- and vug-rimming blocky calcite cement records comparable or slightly lower values of δ 18 O (−16.31‰ to −4.08‰ VPDB, average −9.76‰) and 87 Sr/ 86 Sr (0.70784–0.709743, average 0.70868) and much lower salinity values (0–22.5 wt.\% NaCl, average 2.86 wt.\% NaCl) for samples mostly from the Mississippian age group. These results possibly suggest two different hydrothermal episodes related to early (Antler) and late (Laramide) tectonic events that affected the Western Canada Sedimentary Basin with possible compartmentalization of hydrothermal systems and their associated brines in the basin.",
    url = "https://doi.org/10.1139/cjes-2018-0226",
    doi = "10.1139/cjes-2018-0226",
    openalex = "W2913045111",
    references = "doi1010160016703790901288, doi101016001670379390378a, doi101016016896229090020d, doi101016s0009254199000819, doi1011300091761319821070taatoo20co2, doi1011300091761319861499fetfob20co2, doi101144gslsp20042350102, doi10130604211009178, doi10130605220605164, doi101306212f7b9e2b2411d78648000102c1865d"
}

O values of diagenetic fluids, rare earth element plus yttrium compositions, and petrographic observations of these dolostones are consistent with an early diagenetic origin in a rock-buffered environment. We thus propose that a precursor precipitate from seawater was subsequently dolomitized during early diagenesis in a near-surface setting to produce the large volume of dolostones in the Doushantuo Formation. Our findings suggest that the preponderance of dolomite in Paleozoic and Precambrian deposits likely reflects oceanic conditions specific to those eras and that dolostones can be faithful recorders of environmental conditions in the early oceans.

@article{doi101073pnas1916673117,
    author = "Chang, Biao and Li, Chao and Liu, Deng and Foster, Ian and Tripati, Aradhna and Lloyd, Max K. and Maradiaga, Ingrid and Luo, Genming and An, Zhihui and She, Zhenbing and Xie, Shucheng and Tong, Jinnan and Huang, Junhua and Algeo, Thomas J. and Lyons, Timothy W. and Immenhauser, Adrian",
    title = "Massive formation of early diagenetic dolomite in the Ediacaran ocean: Constraints on the “dolomite problem”",
    year = "2020",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "O values of diagenetic fluids, rare earth element plus yttrium compositions, and petrographic observations of these dolostones are consistent with an early diagenetic origin in a rock-buffered environment. We thus propose that a precursor precipitate from seawater was subsequently dolomitized during early diagenesis in a near-surface setting to produce the large volume of dolostones in the Doushantuo Formation. Our findings suggest that the preponderance of dolomite in Paleozoic and Precambrian deposits likely reflects oceanic conditions specific to those eras and that dolostones can be faithful recorders of environmental conditions in the early oceans.",
    url = "https://doi.org/10.1073/pnas.1916673117",
    doi = "10.1073/pnas.1916673117",
    openalex = "W3032974216",
    references = "doi101007s1143001792910, doi101111sed12202"
}

Integrated petrographic, isotopic, fluid inclusion microthermometry, and geochemical analyses of Paleozoic carbonate successions from multiple boreholes within the Huron Domain, southern Ontario were conducted to characterize the diagenetic history and fluid composition, on a regional scale, and evaluate the nature and origin of dolomitized beds. Multiple generations of non-stochiometric dolomite have been observed. These dolomites occur as both replacement (D1 and D2) and cement (saddle dolomite; SD) and formed either at near-surface to shallow burial zone (D1) or intermediate burial (D2 and SD). Petrographic and geochemical data of dolomite types and calcite cement suggest that these carbonates have experienced multiple fluid events that affected dolomite formation and other diagenetic processes. Cambrian and Ordovician strata have two possibly isolated diagenetic fluid systems; an earlier fluid system that is characterized by a pronounced negative shift in oxygen and carbon isotopic composition, more radiogenic Sr ratios, warm and saline signatures, higher average ∑REE compared to warm water marine brachiopods, negative La anomaly, and positive Ce anomaly; and a later Ordovician system, characterized by less negative shifts in oxygen and carbon isotopes, comparable Th, hypersaline, a less radiogenic, less negative La anomaly, and primarily positive Ce anomaly but also higher average ∑REE compared to warm water marine brachiopods. Ordovician, Silurian, and Devonian Sr isotopic ratios, however, show seawater composition of their respective age as the primary source of diagenetic fluids with minor rock/water interactions. In contrast, the isotopic data of the overlying Silurian and Devonian carbonates show overlaps between δ13C and δ18O values. However, δ18O values show evidence of dolomite recrystallization. D2 shows wide Th values and medium to high salinity values. Higher Th and salinity are observed in SD in the Silurian carbonates, which suggest the involvement of localized fluxes of hydrothermal fluids during its formation during Paleozoic orogenesis. Geochemical proxies suggest that in both age groups the diagenetic fluids were originally of coeval seawater composition, subsequently modified via water-rock interaction possibly related to brines, which were modified by the dissolution of Silurian evaporites from the Salina series. The integration of the obtained data in the present study demonstrates the linkage between fluid flux history, fluid compartmentalization, and related diagenesis during the regional tectonic evolution of the Michigan Basin.

@article{doi103390w13172449,
    author = "Al‐Aasm, Ihsan S. and Crowe, Richard and Tortola, Marco",
    title = "Dolomitization of Paleozoic Successions, Huron Domain of Southern Ontario, Canada: Fluid Flow and Dolomite Evolution",
    year = "2021",
    journal = "Water",
    abstract = "Integrated petrographic, isotopic, fluid inclusion microthermometry, and geochemical analyses of Paleozoic carbonate successions from multiple boreholes within the Huron Domain, southern Ontario were conducted to characterize the diagenetic history and fluid composition, on a regional scale, and evaluate the nature and origin of dolomitized beds. Multiple generations of non-stochiometric dolomite have been observed. These dolomites occur as both replacement (D1 and D2) and cement (saddle dolomite; SD) and formed either at near-surface to shallow burial zone (D1) or intermediate burial (D2 and SD). Petrographic and geochemical data of dolomite types and calcite cement suggest that these carbonates have experienced multiple fluid events that affected dolomite formation and other diagenetic processes. Cambrian and Ordovician strata have two possibly isolated diagenetic fluid systems; an earlier fluid system that is characterized by a pronounced negative shift in oxygen and carbon isotopic composition, more radiogenic Sr ratios, warm and saline signatures, higher average ∑REE compared to warm water marine brachiopods, negative La anomaly, and positive Ce anomaly; and a later Ordovician system, characterized by less negative shifts in oxygen and carbon isotopes, comparable Th, hypersaline, a less radiogenic, less negative La anomaly, and primarily positive Ce anomaly but also higher average ∑REE compared to warm water marine brachiopods. Ordovician, Silurian, and Devonian Sr isotopic ratios, however, show seawater composition of their respective age as the primary source of diagenetic fluids with minor rock/water interactions. In contrast, the isotopic data of the overlying Silurian and Devonian carbonates show overlaps between δ13C and δ18O values. However, δ18O values show evidence of dolomite recrystallization. D2 shows wide Th values and medium to high salinity values. Higher Th and salinity are observed in SD in the Silurian carbonates, which suggest the involvement of localized fluxes of hydrothermal fluids during its formation during Paleozoic orogenesis. Geochemical proxies suggest that in both age groups the diagenetic fluids were originally of coeval seawater composition, subsequently modified via water-rock interaction possibly related to brines, which were modified by the dissolution of Silurian evaporites from the Salina series. The integration of the obtained data in the present study demonstrates the linkage between fluid flux history, fluid compartmentalization, and related diagenesis during the regional tectonic evolution of the Michigan Basin.",
    url = "https://doi.org/10.3390/w13172449",
    doi = "10.3390/w13172449",
    openalex = "W3197435103",
    references = "doi101139cjes20180226"
}

@misc{andsallerNonediagenesis,
    author = "Saller, Arthur",
    title = "Diagenesis of Cenozoic Limestones on Enewetak Atoll (Dolomite, Neomorphism, Radiaxial).",
    year = "None",
    url = "https://doi.org/10.31390/gradschool\_disstheses.3969",
    doi = "10.31390/gradschool\_disstheses.3969"
}