Miocene

@article{doi101038242240a0,
    author = "Hsü, K. J. and Ryan, William B. F. and Cita, Maria Bianca",
    title = "Late Miocene Desiccation of the Mediterranean",
    year = "1973",
    journal = "Nature",
    url = "https://doi.org/10.1038/242240a0",
    doi = "10.1038/242240a0",
    openalex = "W2133346363",
    references = "doi1010160016703788903158, doi101038228199a0, doi101111j136530911971tb00228x, doi102113gssgfbulls6iv79751"
}

@article{doi101007bf00602586,
    author = "Hs�, Kenneth J.",
    title = "The miocene desiccation of the Mediterranean and its climatical and zoogeographical implications",
    year = "1974",
    journal = "Die Naturwissenschaften",
    url = "https://doi.org/10.1007/bf00602586",
    doi = "10.1007/bf00602586",
    openalex = "W2121494202",
    references = "doi101038228199a0"
}

ABSTRACT In Sicily, Messinian evaporitic sedimentary deposits are developed under a wide variety of hypersaline conditions and in environments ranging from continental margin (subaerial), to basin‐margin supratidal, to intertidal, to subtidal and out into the hypersaline basin proper. The actual water depth at the time of deposition is indeterminate; however, relative terms such as ‘wave base’ and ‘photic zone’ are utilized. The inter‐fingering relationships of specific evaporitic facies having clear and recognizable physical characteristics are presented. These include sub‐aerial deposits of nodular calcium sulphate formed displacively within clastic sediments; gypsiferous rudites, arenites and arenitic marls, all of which are reworked sediments and are mixed in varying degrees with other clastic materials (subaerial, supratidal, and intertidal to deep basinal deposits). Laminated calcium sulphate alternating with very thin carbonate interlaminae and having two different aspects; one being even and continuous and the other of a wavy, irregular appearance (subtidal, intertidal, and supratidal deposits). Nodular calcium sulphate beds, usually associated with wavy, irregular laminated beds (supratidal, sabkha deposits); very coarsely crystalline gypsum beds (selenite), associated with more even, laminated beds (subaqueous, intertidal to subtidal deposits); wavy anastomozing gypsum beds, composed of very fine, often broken crystals (subaqueous, current‐swept deposits); halite having hopper and chevron structures (supratidal to intertidal); and halite, potash salts, etc. having continuous laminated structure (subaqueous, possibly basinal). Evidence for diagenetic changes is observed in the calcium sulphate deposits which apparently formed by tectonic stress and also by migrating hypersaline waters. These observations suggest that the common, massive form of alabastrine gypsum (or anhydrite, in the subsurface) may not always be ascribed to original depositional features, to syndiagenesis or to early diagenesis but may be the result of late diagenesis.

@article{doi101111j136530911976tb00107x,
    author = "Schreiber, B. and Friedman, Gerald M. and Decima, A. and Schreiber, Edward",
    title = "Depositional environments of Upper Miocene (Messinian) evaporite deposits of the Sicilian Basin*",
    year = "1976",
    journal = "Sedimentology",
    abstract = "ABSTRACT In Sicily, Messinian evaporitic sedimentary deposits are developed under a wide variety of hypersaline conditions and in environments ranging from continental margin (subaerial), to basin‐margin supratidal, to intertidal, to subtidal and out into the hypersaline basin proper. The actual water depth at the time of deposition is indeterminate; however, relative terms such as ‘wave base’ and ‘photic zone’ are utilized. The inter‐fingering relationships of specific evaporitic facies having clear and recognizable physical characteristics are presented. These include sub‐aerial deposits of nodular calcium sulphate formed displacively within clastic sediments; gypsiferous rudites, arenites and arenitic marls, all of which are reworked sediments and are mixed in varying degrees with other clastic materials (subaerial, supratidal, and intertidal to deep basinal deposits). Laminated calcium sulphate alternating with very thin carbonate interlaminae and having two different aspects; one being even and continuous and the other of a wavy, irregular appearance (subtidal, intertidal, and supratidal deposits). Nodular calcium sulphate beds, usually associated with wavy, irregular laminated beds (supratidal, sabkha deposits); very coarsely crystalline gypsum beds (selenite), associated with more even, laminated beds (subaqueous, intertidal to subtidal deposits); wavy anastomozing gypsum beds, composed of very fine, often broken crystals (subaqueous, current‐swept deposits); halite having hopper and chevron structures (supratidal to intertidal); and halite, potash salts, etc. having continuous laminated structure (subaqueous, possibly basinal). Evidence for diagenetic changes is observed in the calcium sulphate deposits which apparently formed by tectonic stress and also by migrating hypersaline waters. These observations suggest that the common, massive form of alabastrine gypsum (or anhydrite, in the subsurface) may not always be ascribed to original depositional features, to syndiagenesis or to early diagenesis but may be the result of late diagenesis.",
    url = "https://doi.org/10.1111/j.1365-3091.1976.tb00107.x",
    doi = "10.1111/j.1365-3091.1976.tb00107.x",
    openalex = "W2170327774",
    references = "doi101111j136530911971tb00228x, doi10130674d7131b2b2111d78648000102c1865d"
}

ABSTRACT Quantitative geophysical calculations which take into consideration the isostatic loading of sediment overburden, the overlying water cover, and the thermal cooling history of the continental edge, and its adjacent oceanic lithosphere, demonstrate the foundering of the margins of the western Mediterranean had already commenced in the Aquitanian stage of the early Miocene. The calculations are based on magnitudes and rates of sediment accumulation observed along a profile of three commercial boreholes into the subsurface of the continental shelf of southern France. By the time of the late Miocene (Messinian) salinity crisis, the depth of the seafloor within the Balearic basin exceeded 2.5 km. Sea‐level fluctuations induced by evaporitic draw‐down permitted the exposure of large tracts of the former submerged continental margins to subaerial processes. The measured magnitude of sediment removal by erosion and channel incision near the outer shelf of the modern Gulf of Lion surpasses 1 km. The subsidence history of this shelf platform south of France provides new evidence that the continental lithosphere behaves as if it is rigidly coupled to its oceanic counterpart commencing with the initial phase of the pull‐apart. No major vertical fault displacements have subsequently offset their overlying crustal layers. The sedimentary shaping and construction of the margin seaward of the Rhône delta resulted in a pronounced shelf edge migration and slope progradation during the pre‐salinity crisis Miocene. It has taken 5 million years of predominant upbuilding to establish a new equilibrium profile similar in cross‐section to the precrisis depositional surfaces created by outbuilding.

@article{doi101111j136530911976tb00109x,
    author = "Ryan, William B. F.",
    title = "Quantitative evaluation of the depth of the western Mediterranean before, during and after the Late Miocene salinity crisis",
    year = "1976",
    journal = "Sedimentology",
    abstract = "ABSTRACT Quantitative geophysical calculations which take into consideration the isostatic loading of sediment overburden, the overlying water cover, and the thermal cooling history of the continental edge, and its adjacent oceanic lithosphere, demonstrate the foundering of the margins of the western Mediterranean had already commenced in the Aquitanian stage of the early Miocene. The calculations are based on magnitudes and rates of sediment accumulation observed along a profile of three commercial boreholes into the subsurface of the continental shelf of southern France. By the time of the late Miocene (Messinian) salinity crisis, the depth of the seafloor within the Balearic basin exceeded 2.5 km. Sea‐level fluctuations induced by evaporitic draw‐down permitted the exposure of large tracts of the former submerged continental margins to subaerial processes. The measured magnitude of sediment removal by erosion and channel incision near the outer shelf of the modern Gulf of Lion surpasses 1 km. The subsidence history of this shelf platform south of France provides new evidence that the continental lithosphere behaves as if it is rigidly coupled to its oceanic counterpart commencing with the initial phase of the pull‐apart. No major vertical fault displacements have subsequently offset their overlying crustal layers. The sedimentary shaping and construction of the margin seaward of the Rhône delta resulted in a pronounced shelf edge migration and slope progradation during the pre‐salinity crisis Miocene. It has taken 5 million years of predominant upbuilding to establish a new equilibrium profile similar in cross‐section to the precrisis depositional surfaces created by outbuilding.",
    url = "https://doi.org/10.1111/j.1365-3091.1976.tb00109.x",
    doi = "10.1111/j.1365-3091.1976.tb00109.x",
    openalex = "W2004141608"
}

@article{doi1010160025322778900324,
    author = "Ryan, William B. F. and Cita, Maria Bianca",
    title = "The nature and distribution of Messinian erosional surfaces — Indicators of a several-kilometer-deep Mediterranean in the Miocene",
    year = "1978",
    journal = "Marine Geology",
    url = "https://doi.org/10.1016/0025-3227(78)90032-4",
    doi = "10.1016/0025-3227(78)90032-4",
    openalex = "W1982540125",
    references = "doi101111j136530911971tb00228x"
}

@article{doi101038342163a0,
    author = "Quade, Jay and Cerling, Thure E. and Bowman, John R.",
    title = "Development of Asian monsoon revealed by marked ecological shift during the latest Miocene in northern Pakistan",
    year = "1989",
    journal = "Nature",
    url = "https://doi.org/10.1038/342163a0",
    doi = "10.1038/342163a0",
    openalex = "W1995968891",
    references = "doi1010970001069419600900000018, doi101130001676061985961407cg20co2"
}

Oxygen isotope records and glaciomarine sediments indicate at least an intermittent presence of large continental ice sheets on Antarctica since the earliest Oligocene (circa 35 Ma). The growth and decay of ice sheets during the Oligocene to modern “ice house world” caused glacioeustatic sea level changes. The early Eocene was an ice‐free “greenhouse world,” but it is not clear if ice sheets existed during the middle to late Eocene “doubt house world.” Benthic foraminiferal δ 18 O records place limits on the history of glaciation, suggesting the presence of ice sheets at least intermittently since the earliest Oligocene. The best indicator of ice growth is a coeval increase in global benthic and western equatorial planktonic δ 18 O records. Although planktonic isotope records from the western equatorial regions are limited, subtropical planktonic foraminifera may also record such ice volume changes. It is difficult to apply these established principles to the Cenozoic δ 18 O record because of the lack of adequate data and problems in stratigraphic correlations that obscure isotope events. We improved Oligocene to Miocene correlations of δ 18 O records and erected eight oxygen isotope zones (Oi1‐Oi2, Mi1‐Mi6). Benthic foraminiferal δ 18 O increases which are associated with the bases of Zones Oil (circa 35.8 Ma), Oi2 (circa 32.5 Ma), and Mil (circa 23.5 Ma) can be linked with δ 18 O increases in subtropical planktonic foraminifera and with intervals of glacial sedimentation on or near Antarctica. Our new correlations of middle Miocene benthic and western equatorial planktonic δ 18 O records show remarkable agreement in timing and amplitude. We interpret benthic‐planktonic covariance to reflect substantial ice volume increases near the bases of Zones Mi2 (circa 16.1 Ma), Mi3 (circa 13.6 Ma), and possibly Mi5 (circa 11.3 Ma). Possible glacioeustatic lowerings are associated with the δ 18 O increases which culminated with the bases of Zone Mi4 (circa 12.6 Ma) and Mi6 (circa 9.6 Ma), although low‐latitude planktonic δ 18 O records are required to test this. These inferred glacioeustatic lowerings can be linked to seismic and rock disconformities. For example, we link 12 Oligocene‐early late Miocene inferred glacioeustatic lowerings with 12 of the sequence boundaries (= inferred eustatic lowerings) of Haq et al. (1987).

@article{doi10102990jb02015,
    author = "Miller, Kenneth G. and Wright, James D. and Fairbanks, Richard G.",
    title = "Unlocking the Ice House: Oligocene‐Miocene oxygen isotopes, eustasy, and margin erosion",
    year = "1991",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "Oxygen isotope records and glaciomarine sediments indicate at least an intermittent presence of large continental ice sheets on Antarctica since the earliest Oligocene (circa 35 Ma). The growth and decay of ice sheets during the Oligocene to modern “ice house world” caused glacioeustatic sea level changes. The early Eocene was an ice‐free “greenhouse world,” but it is not clear if ice sheets existed during the middle to late Eocene “doubt house world.” Benthic foraminiferal δ 18 O records place limits on the history of glaciation, suggesting the presence of ice sheets at least intermittently since the earliest Oligocene. The best indicator of ice growth is a coeval increase in global benthic and western equatorial planktonic δ 18 O records. Although planktonic isotope records from the western equatorial regions are limited, subtropical planktonic foraminifera may also record such ice volume changes. It is difficult to apply these established principles to the Cenozoic δ 18 O record because of the lack of adequate data and problems in stratigraphic correlations that obscure isotope events. We improved Oligocene to Miocene correlations of δ 18 O records and erected eight oxygen isotope zones (Oi1‐Oi2, Mi1‐Mi6). Benthic foraminiferal δ 18 O increases which are associated with the bases of Zones Oil (circa 35.8 Ma), Oi2 (circa 32.5 Ma), and Mil (circa 23.5 Ma) can be linked with δ 18 O increases in subtropical planktonic foraminifera and with intervals of glacial sedimentation on or near Antarctica. Our new correlations of middle Miocene benthic and western equatorial planktonic δ 18 O records show remarkable agreement in timing and amplitude. We interpret benthic‐planktonic covariance to reflect substantial ice volume increases near the bases of Zones Mi2 (circa 16.1 Ma), Mi3 (circa 13.6 Ma), and possibly Mi5 (circa 11.3 Ma). Possible glacioeustatic lowerings are associated with the δ 18 O increases which culminated with the bases of Zone Mi4 (circa 12.6 Ma) and Mi6 (circa 9.6 Ma), although low‐latitude planktonic δ 18 O records are required to test this. These inferred glacioeustatic lowerings can be linked to seismic and rock disconformities. For example, we link 12 Oligocene‐early late Miocene inferred glacioeustatic lowerings with 12 of the sequence boundaries (= inferred eustatic lowerings) of Haq et al. (1987).",
    url = "https://doi.org/10.1029/90jb02015",
    doi = "10.1029/90jb02015",
    openalex = "W2054410655",
    references = "doi1010160033589473900525, doi101029jc082i027p03843, doi101029jd094id15p18409, doi101029pa002i001p00001, doi101038342637a0, doi10106311671982, doi101126science19442701121, doi101126science23547931156, doi102973dsdpproc291171975, openalexw3160761443"
}

@article{doi1010160031018294902518,
    author = "Flower, B. P. and Kennett, James P.",
    title = "The middle Miocene climatic transition: East Antarctic ice sheet development, deep ocean circulation and global carbon cycling",
    year = "1994",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    url = "https://doi.org/10.1016/0031-0182(94)90251-8",
    doi = "10.1016/0031-0182(94)90251-8",
    openalex = "W2165473271",
    references = "doi101007bf02861083, doi101016004724849090011y, doi1010160305440386900580, doi101016s0047248485800026, doi10102990jb02015, doi101029gm032, doi101029jc082i027p03843, doi101029pa002i001p00001, doi101029pa004i004p00413, doi101038307620a0, doi101126science23547931156, doi1011300091761319920200569eoiseo23co2, doi101146annurevea05050177001535, doi1023071485903, doi102973dsdpproc291171975, openalexw609835849"
}

@article{doi1010160012821x9500207s,
    author = "Hilgen, F.J. and Krijgsman, Wout and Langereis, Cor G. and Lourens, Lucas Joost and Santarelli, A. and Zachariasse, W.J.",
    title = "Extending the astronomical (polarity) time scale into the Miocene",
    year = "1995",
    journal = "Earth and Planetary Science Letters",
    url = "https://doi.org/10.1016/0012-821x(95)00207-s",
    doi = "10.1016/0012-821x(95)00207-s",
    openalex = "W2147985533"
}

@article{doi10103838229,
    author = "Cerling, Thure E. and Harris, John and MacFadden, Bruce J. and Leakey, Meave G. and Quade, Jay and Eisenmann, Véra and Ehleringer, James R.",
    title = "Global vegetation change through the Miocene/Pliocene boundary",
    year = "1997",
    journal = "Nature",
    url = "https://doi.org/10.1038/38229",
    doi = "10.1038/38229",
    openalex = "W1675802314",
    references = "doi101007bf00392238, doi1010160016703778901990, doi1010160016703781902441, doi10102992jb01202, doi101038324237a0, doi101038342163a0, doi101038359117a0, doi101146annurevpp40060189002443, doi102110pec9504, openalexw89992403"
}

Some considerations on the palaeogeography of the Mediterranean and Paratethys Oligocene to Miocene are presented in ten time-slices. The time-slices start with the vanishing Tethys Ocean in the late Eocene and the birth of two new marine realms at its western end: the Mediterranean Sea and the intercontinental Eurasian Paratethys basin. The time-slices were selected according to general palaeogeographic changes of seaways and arising land bridges for continental migrations. The palaeogeographic sketches were based on Cenozoic plate reconstructions, and the intermediate levels are interpolated accordingly. Strong changes occurred in the history of the Paratethys. From an open ocean in the Eocene with connections to the Polar Sea via the Turgai Strait, it changed to an enclosed basin in the early Oligocene with reduced salinity and endemic faunas. From the middle Oligocene on, the basin opened again, reaching a maximum connection with the Indian Ocean during late Oligocene and early Miocene (late Chattian ‐ early Burdigalian). Intermittent seaways and regional close-off of basins with endemic development characterize the late Burdigalian and middle Miocene. By the mid-Serravallian the final disconnection of the Paratethys occurred, and since Sarmatian time reduced salinity conditions and endemisms prevailed. The Mediterranean was the connecting sea between Indo-Pacific and Atlantic Oceans until the late Burdigalian. With the collision of the Arabian and Anatolian plates in the late Burdigalian, an Eurasian ‐ African landbridge opened for mammal migrations. A short interruption is proposed for the Langhian transgression, followed by a final closure in the Serravallian.

@article{openalexw2339284632,
    author = "Fred, Von",
    title = "Palaeogeographic Considerations for Mediterranean and Paratethys Seaways (Oligocene to Miocene)",
    year = "1998",
    abstract = "Some considerations on the palaeogeography of the Mediterranean and Paratethys Oligocene to Miocene are presented in ten time-slices. The time-slices start with the vanishing Tethys Ocean in the late Eocene and the birth of two new marine realms at its western end: the Mediterranean Sea and the intercontinental Eurasian Paratethys basin. The time-slices were selected according to general palaeogeographic changes of seaways and arising land bridges for continental migrations. The palaeogeographic sketches were based on Cenozoic plate reconstructions, and the intermediate levels are interpolated accordingly. Strong changes occurred in the history of the Paratethys. From an open ocean in the Eocene with connections to the Polar Sea via the Turgai Strait, it changed to an enclosed basin in the early Oligocene with reduced salinity and endemic faunas. From the middle Oligocene on, the basin opened again, reaching a maximum connection with the Indian Ocean during late Oligocene and early Miocene (late Chattian ‐ early Burdigalian). Intermittent seaways and regional close-off of basins with endemic development characterize the late Burdigalian and middle Miocene. By the mid-Serravallian the final disconnection of the Paratethys occurred, and since Sarmatian time reduced salinity conditions and endemisms prevailed. The Mediterranean was the connecting sea between Indo-Pacific and Atlantic Oceans until the late Burdigalian. With the collision of the Arabian and Anatolian plates in the late Burdigalian, an Eurasian ‐ African landbridge opened for mammal migrations. A short interruption is proposed for the Langhian transgression, followed by a final closure in the Serravallian.",
    url = "https://openalex.org/W2339284632",
    openalex = "W2339284632",
    references = "doi1010160040195188902594, doi10113000917613198614535scaia20co2, doi102110pec8537, doi102110pec85370211, doi102110pec88010071, doi102110pec95040129, doi1023073060311, openalexw3190829860, openalexw625363362, openalexw878004301"
}

@article{doi105860choice373363,
    title = "The Miocene land mammals of Europe",
    year = "2000",
    journal = "Choice Reviews Online",
    url = "https://doi.org/10.5860/choice.37-3363",
    doi = "10.5860/choice.37-3363",
    openalex = "W62530489"
}

@article{doi10103835075035,
    author = "An, Zhisheng and Kutzbach, John E. and Prell, Warren L and Porter, Stephen C.",
    title = "Evolution of Asian monsoons and phased uplift of the Himalaya–Tibetan plateau since Late Miocene times",
    year = "2001",
    journal = "Nature",
    url = "https://doi.org/10.1038/35075035",
    doi = "10.1038/35075035",
    openalex = "W1637856870",
    references = "doi1010160031018289901430, doi10102993rg02030, doi101029jb091ib03p03664, doi10103831447, doi101038342163a0, doi101038375305a0, doi10103838229, doi101126science25550521663, doi101126science2765313788, doi1011300091761319880160649iolcmb23co2"
}

Spectral analyses of an uninterrupted 5.5-million-year (My)-long chronology of late Oligocene-early Miocene climate and ocean carbon chemistry from two deep-sea cores recovered in the western equatorial Atlantic reveal variance concentrated at all Milankovitch frequencies. Exceptional spectral power in climate is recorded at the 406-thousand-year (ky) period eccentricity band over a 3.4-million-year period [20 to 23.4 My ago (Ma)] as well as in the 125- and 95-ky bands over a 1.3-million-year period (21.7 to 23.0 Ma) of suspected low greenhouse gas levels. Moreover, a major transient glaciation at the epoch boundary (approximately 23 Ma), Mi-1, corresponds with a rare orbital congruence involving obliquity and eccentricity. The anomaly, which consists of low-amplitude variance in obliquity (a node) and a minimum in eccentricity, results in an extended period (approximately 200 ky) of low seasonality orbits favorable to ice-sheet expansion on Antarctica.

@article{doi101126science1058288,
    author = "Zachos, James C. and Shackleton, Nicholas J and Revenaugh, J. and Pälike, Heiko and Flower, B. P.",
    title = "Climate Response to Orbital Forcing Across the Oligocene-Miocene Boundary",
    year = "2001",
    journal = "Science",
    abstract = "Spectral analyses of an uninterrupted 5.5-million-year (My)-long chronology of late Oligocene-early Miocene climate and ocean carbon chemistry from two deep-sea cores recovered in the western equatorial Atlantic reveal variance concentrated at all Milankovitch frequencies. Exceptional spectral power in climate is recorded at the 406-thousand-year (ky) period eccentricity band over a 3.4-million-year period [20 to 23.4 My ago (Ma)] as well as in the 125- and 95-ky bands over a 1.3-million-year period (21.7 to 23.0 Ma) of suspected low greenhouse gas levels. Moreover, a major transient glaciation at the epoch boundary (approximately 23 Ma), Mi-1, corresponds with a rare orbital congruence involving obliquity and eccentricity. The anomaly, which consists of low-amplitude variance in obliquity (a node) and a minimum in eccentricity, results in an extended period (approximately 200 ky) of low seasonality orbits favorable to ice-sheet expansion on Antarctica.",
    url = "https://doi.org/10.1126/science.1058288",
    doi = "10.1126/science.1058288",
    openalex = "W2061161672",
    references = "doi10102996pa00571"
}

@article{doi101016s0031018203003675,
    author = "Böhme, Madelaine",
    title = "The Miocene Climatic Optimum: evidence from ectothermic vertebrates of Central Europe",
    year = "2003",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    url = "https://doi.org/10.1016/s0031-0182(03)00367-5",
    doi = "10.1016/s0031-0182(03)00367-5",
    openalex = "W2016706802",
    references = "doi101016003101828890096x, doi1010160031018294902518, doi101016s0031018297001089, doi105860choice373363, doi105962bhlpart22969, openalexw2339284632"
}

Magnesium/calcium data from Southern Ocean planktonic foraminifera demonstrate that high-latitude (approximately 55 degrees S) southwest Pacific sea surface temperatures (SSTs) cooled 6 degrees to 7 degrees C during the middle Miocene climate transition (14.2 to 13.8 million years ago). Stepwise surface cooling is paced by eccentricity forcing and precedes Antarctic cryosphere expansion by approximately 60 thousand years, suggesting the involvement of additional feedbacks during this interval of inferred low-atmospheric partial pressure of CO2 (pCO2). Comparing SSTs and global carbon cycling proxies challenges the notion that episodic pCO2 drawdown drove this major Cenozoic climate transition. SST, salinity, and ice-volume trends suggest instead that orbitally paced ocean circulation changes altered meridional heat/vapor transport, triggering ice growth and global cooling.

@article{doi101126science1100061,
    author = "Shevenell, Amelia and Kennett, James P. and Lea, David W.",
    title = "Middle Miocene Southern Ocean Cooling and Antarctic Cryosphere Expansion",
    year = "2004",
    journal = "Science",
    abstract = "Magnesium/calcium data from Southern Ocean planktonic foraminifera demonstrate that high-latitude (approximately 55 degrees S) southwest Pacific sea surface temperatures (SSTs) cooled 6 degrees to 7 degrees C during the middle Miocene climate transition (14.2 to 13.8 million years ago). Stepwise surface cooling is paced by eccentricity forcing and precedes Antarctic cryosphere expansion by approximately 60 thousand years, suggesting the involvement of additional feedbacks during this interval of inferred low-atmospheric partial pressure of CO2 (pCO2). Comparing SSTs and global carbon cycling proxies challenges the notion that episodic pCO2 drawdown drove this major Cenozoic climate transition. SST, salinity, and ice-volume trends suggest instead that orbitally paced ocean circulation changes altered meridional heat/vapor transport, triggering ice growth and global cooling.",
    url = "https://doi.org/10.1126/science.1100061",
    doi = "10.1126/science.1100061",
    openalex = "W2070511571",
    references = "doi1010160031018294902518, doi101126science29255252310"
}

@article{doi101130b252751,
    author = "Coates, Anthony G. and Collins, Laurel S. and Aubry, Marie‐Pierre and Berggren, William A.",
    title = "The Geology of the Darien, Panama, and the late Miocene-Pliocene collision of the Panama arc with northwestern South America",
    year = "2004",
    journal = "Geological Society of America Bulletin",
    url = "https://doi.org/10.1130/b25275.1",
    doi = "10.1130/b25275.1",
    openalex = "W1989154502"
}

@article{doi101016jpalaeo200603020,
    author = "Popov, Sergej V. and Shcherba, I. G. and Ilyina, Lubov B. and Nevesskaya, L. A. and Paramonova, Nina P. and Khondkarian, Sergej O. and Magyar, Imre",
    title = "Late Miocene to Pliocene palaeogeography of the Paratethys and its relation to the Mediterranean",
    year = "2006",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    url = "https://doi.org/10.1016/j.palaeo.2006.03.020",
    doi = "10.1016/j.palaeo.2006.03.020",
    openalex = "W2011948344",
    references = "doi105860choice373363, openalexw2339284632"
}

@article{doi101016jpalaeo200603042,
    author = "Fortelius, Mikael and Eronen, Jussi T. and Liu, Liping and Pushkina, Diana and Тесаков, А. С. and Вислобокова, И. А. and Zhang, Zhaoqun",
    title = "Late Miocene and Pliocene large land mammals and climatic changes in Eurasia",
    year = "2006",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    url = "https://doi.org/10.1016/j.palaeo.2006.03.042",
    doi = "10.1016/j.palaeo.2006.03.042",
    openalex = "W2152671517",
    references = "openalexw2339284632"
}

@article{doi101007s0053100702699,
    author = "Reuter, Markus and Piller, Werner E. and Harzhauser, Mathias and Mandić, Oleg and Berning, Björn and Rögl, Fred and Kroh, Andreas and Aubry, Marie‐Pierre and Wielandt‐Schuster, Ulrike and Hamedani, Ali",
    title = "The Oligo-/Miocene Qom Formation (Iran): evidence for an early Burdigalian restriction of the Tethyan Seaway and closure of its Iranian gateways",
    year = "2007",
    journal = "International Journal of Earth Sciences",
    url = "https://doi.org/10.1007/s00531-007-0269-9",
    doi = "10.1007/s00531-007-0269-9",
    openalex = "W2107711737",
    references = "doi101017s0094837300011507, openalexw2339284632"
}

@article{doi101016jjcz200705001,
    author = "Harzhauser, Mathias and Kroh, Andreas and Mandić, Oleg and Piller, Werner E. and Göhlich, Ursula B. and Reuter, Markus and Berning, Björn",
    title = "Biogeographic responses to geodynamics: A key study all around the Oligo–Miocene Tethyan Seaway",
    year = "2007",
    journal = "Zoologischer Anzeiger",
    url = "https://doi.org/10.1016/j.jcz.2007.05.001",
    doi = "10.1016/j.jcz.2007.05.001",
    openalex = "W2148542039",
    references = "doi101038267399a0, doi101111j155856461973tb00719x, doi101144gslsp19880370119, doi102110pec98020003, doi1023072407204, doi105860choice373363, openalexw2339284632"
}

@article{doi101016jpalaeo200703031,
    author = "Harzhauser, Mathias and Piller, Werner E.",
    title = "Benchmark data of a changing sea — Palaeogeography, Palaeobiogeography and events in the Central Paratethys during the Miocene",
    year = "2007",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    url = "https://doi.org/10.1016/j.palaeo.2007.03.031",
    doi = "10.1016/j.palaeo.2007.03.031",
    openalex = "W2096537029",
    references = "doi10108000241160410006483, doi1018814epiiugs2004v27i2002, doi102110pec98020003, doi105860choice373363, openalexw2339284632"
}

The Miocene is characterized by a series of key climatic events that led to the founding of the late Cenozoic icehouse mode and the dawn of modern biota. The processes that caused these developments, and particularly the role of atmospheric CO 2 as a forcing factor, are poorly understood. Here we present a CO 2 record based on stomatal frequency data from multiple tree species. Our data show striking CO 2 fluctuations of ≈600–300 parts per million by volume (ppmv). Periods of low CO 2 are contemporaneous with major glaciations, whereas elevated CO 2 of 500 ppmv coincides with the climatic optimum in the Miocene. Our data point to a long-term coupling between atmospheric CO 2 and climate. Major changes in Miocene terrestrial ecosystems, such as the expansion of grasslands and radiations among terrestrial herbivores such as horses, can be linked to these marked fluctuations in CO 2.

@article{doi101073pnas0708588105,
    author = "Kürschner, Wolfram M. and Kvaček, Zlatko and Dilcher, David L.",
    title = "The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of terrestrial ecosystems",
    year = "2008",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "The Miocene is characterized by a series of key climatic events that led to the founding of the late Cenozoic icehouse mode and the dawn of modern biota. The processes that caused these developments, and particularly the role of atmospheric CO 2 as a forcing factor, are poorly understood. Here we present a CO 2 record based on stomatal frequency data from multiple tree species. Our data show striking CO 2 fluctuations of ≈600–300 parts per million by volume (ppmv). Periods of low CO 2 are contemporaneous with major glaciations, whereas elevated CO 2 of 500 ppmv coincides with the climatic optimum in the Miocene. Our data point to a long-term coupling between atmospheric CO 2 and climate. Major changes in Miocene terrestrial ecosystems, such as the expansion of grasslands and radiations among terrestrial herbivores such as horses, can be linked to these marked fluctuations in CO 2.",
    url = "https://doi.org/10.1073/pnas.0708588105",
    doi = "10.1073/pnas.0708588105",
    openalex = "W2051680091",
    references = "doi101073pnas0505267102"
}

Abstract. The global climate system experienced a series of drastic changes during the Cenozoic. In Asia, these include the climate transformation from a zonal pattern to a monsoon-dominated pattern, the disappearance of typical subtropical aridity, and the onset of inland deserts. Despite major advances in the last two decades in characterizing and understanding these climate phenomena, disagreements persist relative to the timing, behaviors and underlying causes. This paper addresses these issues mainly based on two lines of evidence. First, we compiled newly collected data from geological indicators of the Cenozoic environment in China as paleoenvironmental maps of ten intervals. In confirming the earlier observation that a zonal climate pattern was transformed into a monsoonal one, the maps within the Miocene indicate that this change was achieved by the early Miocene, roughly consistent with the onset of loess deposition in China. Although a monsoon-like regime would have existed in the Eocene, it was restricted to tropical-subtropical regions. The latitudinal oscillations of the climate zones during the Paleogene are likely attributable to the imbalance in evolution of polar ice-sheets between the two hemispheres. Secondly, we examine the relevant depositional and soil forming processes of the Miocene loess-soil sequences to determine the circulation characteristics with emphasis on the early Miocene. Continuous eolian deposition in the middle reaches of the Yellow River since the early Miocene firmly indicates the formation of inland deserts, which have been constantly maintained during the past 22 Ma. Grain-size gradients between loess sections indicate northerly dust-carrying winds from northern sources, a clear indication of an Asian winter monsoon system. Meanwhile, well-developed Luvisols show evidence that moisture from the oceans reached northern China. This evidence shows the coexistence of two kinds of circulations, one from the ocean carrying moisture and another from the inland deserts transporting dust. The formation of the early Miocene paleosols resulted from interactive soil forming and dust deposition processes in these two seasonally alternating monsoonal circulations. The much stronger development of the early Miocene soils compared to those in the Quaternary loess indicates that summer monsoons were either significantly stronger, more persistent through the year, or both. These lines of evidence indicate a joint change in circulation and inland aridity by the early Miocene and suggest a dynamic linkage of them. Our recent sensitivity tests with a general circulation model, along with relevant geological data, suggest that the onset of these contrasting wet/dry responses, as well as the change from the "planetary" subtropical aridity pattern to the "inland" aridity pattern, resulted from the combined effects of Tibetan uplift and withdrawal of the Paratethys seaway in central Asia, as suggested by earlier experiments. The spreading of South China Sea also helped to enhance the south-north contrast of humidity. The Miocene loess record provides a vital insight that these tectonic factors had evolved by the early Miocene to a threshold sufficient to cause this major climate reorganization in Asia.

@article{doi105194cp41532008,
    author = "Guo, Zhengtang and Sun, Bainian and Zhang, Zhongshi and Peng, Shuyang and Xiao, Guoqiao and Ge, Junyi and Hao, Qingzhen and Qiao, Ying and Liang, Meiyan and Liu, Jianfang and Yin, Qiuzhen and Wei, J. J.",
    title = "A major reorganization of Asian climate by the early Miocene",
    year = "2008",
    journal = "Climate of the past",
    abstract = {Abstract. The global climate system experienced a series of drastic changes during the Cenozoic. In Asia, these include the climate transformation from a zonal pattern to a monsoon-dominated pattern, the disappearance of typical subtropical aridity, and the onset of inland deserts. Despite major advances in the last two decades in characterizing and understanding these climate phenomena, disagreements persist relative to the timing, behaviors and underlying causes. This paper addresses these issues mainly based on two lines of evidence. First, we compiled newly collected data from geological indicators of the Cenozoic environment in China as paleoenvironmental maps of ten intervals. In confirming the earlier observation that a zonal climate pattern was transformed into a monsoonal one, the maps within the Miocene indicate that this change was achieved by the early Miocene, roughly consistent with the onset of loess deposition in China. Although a monsoon-like regime would have existed in the Eocene, it was restricted to tropical-subtropical regions. The latitudinal oscillations of the climate zones during the Paleogene are likely attributable to the imbalance in evolution of polar ice-sheets between the two hemispheres. Secondly, we examine the relevant depositional and soil forming processes of the Miocene loess-soil sequences to determine the circulation characteristics with emphasis on the early Miocene. Continuous eolian deposition in the middle reaches of the Yellow River since the early Miocene firmly indicates the formation of inland deserts, which have been constantly maintained during the past 22 Ma. Grain-size gradients between loess sections indicate northerly dust-carrying winds from northern sources, a clear indication of an Asian winter monsoon system. Meanwhile, well-developed Luvisols show evidence that moisture from the oceans reached northern China. This evidence shows the coexistence of two kinds of circulations, one from the ocean carrying moisture and another from the inland deserts transporting dust. The formation of the early Miocene paleosols resulted from interactive soil forming and dust deposition processes in these two seasonally alternating monsoonal circulations. The much stronger development of the early Miocene soils compared to those in the Quaternary loess indicates that summer monsoons were either significantly stronger, more persistent through the year, or both. These lines of evidence indicate a joint change in circulation and inland aridity by the early Miocene and suggest a dynamic linkage of them. Our recent sensitivity tests with a general circulation model, along with relevant geological data, suggest that the onset of these contrasting wet/dry responses, as well as the change from the "planetary" subtropical aridity pattern to the "inland" aridity pattern, resulted from the combined effects of Tibetan uplift and withdrawal of the Paratethys seaway in central Asia, as suggested by earlier experiments. The spreading of South China Sea also helped to enhance the south-north contrast of humidity. The Miocene loess record provides a vital insight that these tectonic factors had evolved by the early Miocene to a threshold sufficient to cause this major climate reorganization in Asia.},
    url = "https://doi.org/10.5194/cp-4-153-2008",
    doi = "10.5194/cp-4-153-2008",
    openalex = "W2135644396",
    references = "doi10102992jb02280, doi10102994jb03098, doi101029pa002i001p00001, doi10103835021000, doi10103835075035, doi101038359117a0, doi101038416159a, doi101126science1059412, doi101126science25550521663, doi101126science2875451269"
}

@article{doi101016jrevpalbo200908001,
    author = "Jiménez‐Moreno, Gonzalo and Fauquette, Séverine and Suc, Jean‐Pierre",
    title = "Miocene to Pliocene vegetation reconstruction and climate estimates in the Iberian Peninsula from pollen data",
    year = "2009",
    journal = "Review of Palaeobotany and Palynology",
    url = "https://doi.org/10.1016/j.revpalbo.2009.08.001",
    doi = "10.1016/j.revpalbo.2009.08.001",
    openalex = "W2028908634",
    references = "doi101073pnas0505267102, openalexw2339284632"
}

@article{doi101016jearscirev201202003,
    author = "Miao, Yunfa and Herrmann, Mark and Wu, Fuli and Yan, Xiaoli and Yang, Shengli",
    title = "What controlled Mid–Late Miocene long-term aridification in Central Asia? — Global cooling or Tibetan Plateau uplift: A review",
    year = "2012",
    journal = "Earth-Science Reviews",
    url = "https://doi.org/10.1016/j.earscirev.2012.02.003",
    doi = "10.1016/j.earscirev.2012.02.003",
    openalex = "W1993190436",
    references = "doi101016jepsl200511028, doi101038ngeo351, doi101073pnas0505267102, doi105194cp41532008, openalexw2339284632"
}

@article{doi101016jearscirev201202005,
    author = "Pound, Matthew J. and Haywood, Alan M. and Salzmann, Ulrich and Riding, James B.",
    title = "Global vegetation dynamics and latitudinal temperature gradients during the Mid to Late Miocene (15.97–5.33Ma)",
    year = "2012",
    journal = "Earth-Science Reviews",
    url = "https://doi.org/10.1016/j.earscirev.2012.02.005",
    doi = "10.1016/j.earscirev.2012.02.005",
    openalex = "W2071434576",
    references = "doi101017s0022336000036362, doi101073pnas0505267102, doi101130b262311, doi1016660022336020050790185bgabhg20co2"
}

@article{doi101016jearscirev201508007,
    author = "Flecker, Rachel and Krijgsman, Wout and Capella, Walter and Martins, César C. and Dmitrieva, Evelina and Mayser, Jan Peter and Marzocchi, Alice and Modestou, Sevasti and Ochoa, Diana and Simon, Dirk and Tulbure, M.A. and van den Berg, Bas and van der Schee, Marlies and de Lange, Gert J. and Ellam, R. M. and Govers, Rob and Gutjahr, Marcus and Hilgen, Frits and Kouwenhoven, Tanja J. and Lofi, Johanna and Meijer, Paul and Sierro, Francisco Javier and Bachiri, Naima and Barhoun, Nadia and Alami, Abdelwahid Chakor and Chacón, B. and Flores, José‐Abel and Gregory, John and Howard, James D. and Lunt, Daniel J. and Ochoa, M. and Pancost, Richard D. and Vincent, Stephen J. and Yousfi, M.Z.",
    title = "Evolution of the Late Miocene Mediterranean–Atlantic gateways and their impact on regional and global environmental change",
    year = "2015",
    journal = "Earth-Science Reviews",
    url = "https://doi.org/10.1016/j.earscirev.2015.08.007",
    doi = "10.1016/j.earscirev.2015.08.007",
    openalex = "W1942290710",
    references = "doi101016jearscirev200911004, doi101016jmargeo201402002, doi101016jsedgeo200602005, doi101038nature05163, doi101038nature08555"
}

Uranium-lead geochronology in detrital zircons and provenance analyses in eight boreholes and two surface stratigraphic sections in the northern Andes provide insight into the time of closure of the Central American Seaway. The timing of this closure has been correlated with Plio-Pleistocene global oceanographic, atmospheric, and biotic events. We found that a uniquely Panamanian Eocene detrital zircon fingerprint is pronounced in middle Miocene fluvial and shallow marine strata cropping out in the northern Andes but is absent in underlying lower Miocene and Oligocene strata. We contend that this fingerprint demonstrates a fluvial connection, and therefore the absence of an intervening seaway, between the Panama arc and South America in middle Miocene times; the Central American Seaway had vanished by that time.

@article{doi101126scienceaaa2815,
    author = "Montes, Camilo and Cardona, A. and Jaramillo, Carlos and Pardo, Andrés and Silva, J. C. and Valencia, V. and Ayala, Carolina and Pérez-Ángel, Lina C. and Rodriguez-Parra, L. A. and Ramirez, V. and Niño, H.",
    title = "Middle Miocene closure of the Central American Seaway",
    year = "2015",
    journal = "Science",
    abstract = "Uranium-lead geochronology in detrital zircons and provenance analyses in eight boreholes and two surface stratigraphic sections in the northern Andes provide insight into the time of closure of the Central American Seaway. The timing of this closure has been correlated with Plio-Pleistocene global oceanographic, atmospheric, and biotic events. We found that a uniquely Panamanian Eocene detrital zircon fingerprint is pronounced in middle Miocene fluvial and shallow marine strata cropping out in the northern Andes but is absent in underlying lower Miocene and Oligocene strata. We contend that this fingerprint demonstrates a fluvial connection, and therefore the absence of an intervening seaway, between the Panama arc and South America in middle Miocene times; the Central American Seaway had vanished by that time.",
    url = "https://doi.org/10.1126/science.aaa2815",
    doi = "10.1126/science.aaa2815",
    openalex = "W2033260914",
    references = "doi101016003101829090178a, doi101016jepsl200909013, doi1010292005gc001100, doi1010292011jb008959, doi101126science21545381351, doi1011300091761320010290207ropuoo20co2, doi101130b252751, doi101130b305281, doi101130g322371, doi101144gsjgs14460893"
}

@article{doi101038ngeo2813,
    author = "Herbert, Timothy D. and Lawrence, K. T. and Tzanova, Alexandrina and Peterson, L. C. and Caballero-Gill, Rocio P and Kelly, Christopher S",
    title = "Late Miocene global cooling and the rise of modern ecosystems",
    year = "2016",
    journal = "Nature Geoscience",
    url = "https://doi.org/10.1038/ngeo2813",
    doi = "10.1038/ngeo2813",
    openalex = "W2526517389",
    references = "doi101007s004420050311, doi1010160016703788901329, doi101016jearscirev201203002, doi101016s0016703798000970, doi10102996jb00104, doi10103838229, doi101126science1059412, doi10121411ba618, doi101214ba1339616472, doi102973odpprocsr1271281992"
}

@article{doi101016jgloplacha201709013,
    author = "Palcu, Dan V. and Golovina, L. А. and Vernyhorova, Yu.V. and Попов, С. В. and Krijgsman, Wout",
    title = "Middle Miocene paleoenvironmental crises in Central Eurasia caused by changes in marine gateway configuration",
    year = "2017",
    journal = "Global and Planetary Change",
    url = "https://doi.org/10.1016/j.gloplacha.2017.09.013",
    doi = "10.1016/j.gloplacha.2017.09.013",
    openalex = "W2759017310",
    references = "doi101016jmargeo201402002"
}

The late Miocene offers the opportunity to assess the sensitivity of the Earth's climate to orbital forcing and to changing boundary conditions, such as ice volume and greenhouse gas concentrations, on a warmer-than-modern Earth. Here we investigate the relationships between low- and high-latitude climate variability in an extended succession from the subtropical northwestern Pacific Ocean. Our high-resolution benthic isotope record in combination with paired mixed layer isotope and Mg/Ca-derived temperature data reveal that a long-term cooling trend was synchronous with intensification of the Asian winter monsoon and strengthening of the biological pump from ~7 Ma until ~5.5 Ma. The climate shift occurred at the end of a global δ13C decrease, suggesting that changes in the carbon cycle involving the terrestrial and deep ocean carbon reservoirs were instrumental in driving late Miocene climate cooling. The inception of cooler climate conditions culminated with ephemeral Northern Hemisphere glaciations between 6.0 and 5.5 Ma.

@article{doi101038s41467018039501,
    author = "Holbourn, Ann E and Kuhnt, Wolfgang and Clemens, Steven C and Kochhann, Karlos G D and Jöhnck, Janika and Lübbers, Julia and Andersen, Nils",
    title = "Late Miocene climate cooling and intensification of southeast Asian winter monsoon.",
    year = "2018",
    journal = "Nature communications",
    abstract = "The late Miocene offers the opportunity to assess the sensitivity of the Earth's climate to orbital forcing and to changing boundary conditions, such as ice volume and greenhouse gas concentrations, on a warmer-than-modern Earth. Here we investigate the relationships between low- and high-latitude climate variability in an extended succession from the subtropical northwestern Pacific Ocean. Our high-resolution benthic isotope record in combination with paired mixed layer isotope and Mg/Ca-derived temperature data reveal that a long-term cooling trend was synchronous with intensification of the Asian winter monsoon and strengthening of the biological pump from \textasciitilde 7 Ma until \textasciitilde 5.5 Ma. The climate shift occurred at the end of a global δ13C decrease, suggesting that changes in the carbon cycle involving the terrestrial and deep ocean carbon reservoirs were instrumental in driving late Miocene climate cooling. The inception of cooler climate conditions culminated with ephemeral Northern Hemisphere glaciations between 6.0 and 5.5 Ma.",
    url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC5910391/",
    doi = "10.1038/s41467-018-03950-1",
    pmcid = "PMC5910391",
    pmid = "29679005"
}

@article{doi101130g402281,
    author = "Super, J. R. and Thomas, Ellen and Pagani, Mark and Huber, Matthew and O’Brien, Charlotte L. and Hull, Pincelli M.",
    title = "North Atlantic temperature and pCO2 coupling in the early-middle Miocene",
    year = "2018",
    journal = "Geology",
    url = "https://doi.org/10.1130/g40228.1",
    doi = "10.1130/g40228.1",
    openalex = "W2800436021",
    references = "doi101038ngeo2813"
}

Abstract The Miocene epoch (23.03–5.33 Ma) was a time interval of global warmth, relative to today. Continental configurations and mountain topography transitioned toward modern conditions, and many flora and fauna evolved into the same taxa that exist today. Miocene climate was dynamic: long periods of early and late glaciation bracketed a ∼2 Myr greenhouse interval—the Miocene Climatic Optimum (MCO). Floras, faunas, ice sheets, precipitation, p CO 2, and ocean and atmospheric circulation mostly (but not ubiquitously) covaried with these large changes in climate. With higher temperatures and moderately higher p CO 2 (∼400–600 ppm), the MCO has been suggested as a particularly appropriate analog for future climate scenarios, and for assessing the predictive accuracy of numerical climate models—the same models that are used to simulate future climate. Yet, Miocene conditions have proved difficult to reconcile with models. This implies either missing positive feedbacks in the models, a lack of knowledge of past climate forcings, or the need for re‐interpretation of proxies, which might mitigate the model‐data discrepancy. Our understanding of Miocene climatic, biogeochemical, and oceanic changes on broad spatial and temporal scales is still developing. New records documenting the physical, chemical, and biotic aspects of the Earth system are emerging, and together provide a more comprehensive understanding of this important time interval. Here, we review the state‐of‐the‐art in Miocene climate, ocean circulation, biogeochemical cycling, ice sheet dynamics, and biotic adaptation research as inferred through proxy observations and modeling studies.

@article{doi1010292020pa004037,
    author = "Steinthorsdottir, Margret and Coxall, Helen K. and de Boer, Agatha M. and Huber, Matthew and Barbolini, Natasha and Bradshaw, Catherine P. and Burls, Natalie and Feakins, Sarah J. and Gasson, E. and Henderiks, Jorijntje and Holbourn, Ann and Kiel, Steffen and Kohn, Matthew J. and Knorr, Gregor and Kürschner, Wolfram M. and Lear, Caroline H. and Liebrand, Diederik and Lunt, Daniel J. and Mörs, Thomas and Pearson, Paul N. and Pound, Matthew J. and Stoll, Heather and Strömberg, Caroline A. E.",
    title = "The Miocene: The Future of the Past",
    year = "2020",
    journal = "Paleoceanography and Paleoclimatology",
    abstract = "Abstract The Miocene epoch (23.03–5.33 Ma) was a time interval of global warmth, relative to today. Continental configurations and mountain topography transitioned toward modern conditions, and many flora and fauna evolved into the same taxa that exist today. Miocene climate was dynamic: long periods of early and late glaciation bracketed a ∼2 Myr greenhouse interval—the Miocene Climatic Optimum (MCO). Floras, faunas, ice sheets, precipitation, p CO 2, and ocean and atmospheric circulation mostly (but not ubiquitously) covaried with these large changes in climate. With higher temperatures and moderately higher p CO 2 (∼400–600 ppm), the MCO has been suggested as a particularly appropriate analog for future climate scenarios, and for assessing the predictive accuracy of numerical climate models—the same models that are used to simulate future climate. Yet, Miocene conditions have proved difficult to reconcile with models. This implies either missing positive feedbacks in the models, a lack of knowledge of past climate forcings, or the need for re‐interpretation of proxies, which might mitigate the model‐data discrepancy. Our understanding of Miocene climatic, biogeochemical, and oceanic changes on broad spatial and temporal scales is still developing. New records documenting the physical, chemical, and biotic aspects of the Earth system are emerging, and together provide a more comprehensive understanding of this important time interval. Here, we review the state‐of‐the‐art in Miocene climate, ocean circulation, biogeochemical cycling, ice sheet dynamics, and biotic adaptation research as inferred through proxy observations and modeling studies.",
    url = "https://doi.org/10.1029/2020pa004037",
    doi = "10.1029/2020pa004037",
    openalex = "W3115744292",
    references = "doi101016b9780444594259000299, doi101016jmargeo201402002, doi101017cbo9781107415324024, doi1010292004pa001071, doi101038242240a0, doi101038nature03135, doi101038nature06588, doi101038nature06949, doi101038ngeo2813, doi1010510004636120041335, doi101126sciadvaaz1346, doi101126science1116412, doi101126scienceaaa2815, doi1016410006356820010510933teotwa20co2, doi1018814epiiugs2013v36i3002, doi1023071485834, doi105860choice373363, openalexw1480092759"
}

During the Mid-Miocene Climatic Optimum [MMCO, ~14 to 17 million years (Ma) ago], global temperatures were similar to predicted temperatures for the coming century. Limited megathermal paleoclimatic and fossil data are known from this period, despite its potential as an analog for future climate conditions. Here, we report a rich middle Miocene rainforest biome, the Zhangpu biota (~14.7 Ma ago), based on material preserved in amber and associated sedimentary rocks from southeastern China. The record shows that the mid-Miocene rainforest reached at least 24.2°N and was more widespread than previously estimated. Our results not only highlight the role of tropical rainforests acting as evolutionary museums for biodiversity at the generic level but also suggest that the MMCO probably strongly shaped the East Asian biota via the northern expansion of the megathermal rainforest biome. The Zhangpu biota provides an ideal snapshot for biodiversity redistribution during global warming.

@article{doi101126sciadvabg0625,
    author = "Wáng, Bó and Shi, Gongle and Xu, Chunpeng and Spicer, Robert A. and Perrichot, Vincent and Schmidt, Alexander R. and Feldberg, Kathrin and Heinrichs, Jochen and Chény, Cédric and Pang, Hong and Liu, Xingyue and Gao, Taiping and Wang, Zixi and Ślipiński, Adam and Solórzano‐Kraemer, Mónica M. and Heads, Sam W. and Thomas, M. Jared and Sadowski, Eva‐Maria and Szwedo, Jacek and Azar, Dany and Nel, André and Liu, Ye and Chen, Jun and Zhang, Qi and Zhang, Qingqing and Luo, Cihang and Yu, Tingting and Zheng, Daran and Zhang, Haichun and Engel, Michael S.",
    title = "The mid-Miocene Zhangpu biota reveals an outstandingly rich rainforest biome in East Asia",
    year = "2021",
    journal = "Science Advances",
    abstract = "During the Mid-Miocene Climatic Optimum [MMCO, \textasciitilde 14 to 17 million years (Ma) ago], global temperatures were similar to predicted temperatures for the coming century. Limited megathermal paleoclimatic and fossil data are known from this period, despite its potential as an analog for future climate conditions. Here, we report a rich middle Miocene rainforest biome, the Zhangpu biota (\textasciitilde 14.7 Ma ago), based on material preserved in amber and associated sedimentary rocks from southeastern China. The record shows that the mid-Miocene rainforest reached at least 24.2°N and was more widespread than previously estimated. Our results not only highlight the role of tropical rainforests acting as evolutionary museums for biodiversity at the generic level but also suggest that the MMCO probably strongly shaped the East Asian biota via the northern expansion of the megathermal rainforest biome. The Zhangpu biota provides an ideal snapshot for biodiversity redistribution during global warming.",
    url = "https://doi.org/10.1126/sciadv.abg0625",
    doi = "10.1126/sciadv.abg0625",
    openalex = "W3157851480",
    references = "doi101016jearscirev201202005, doi101017cbo9780511626838, doi1010292020pa004037, doi101038nature25485, doi101126scienceaad8466, doi101126scienceaai9214, doi101126scienceaat3466, doi1023073515620, doi103897phytokeys596261, openalexw636623882"
}

Among the many inclusions from the exceptionally rich fossiliferous amber of Zhangpu, China (Middle Miocene: Langhian), stingless bees (Apinae: Meliponini) are particularly common, analogous to the merely slightly older amber sites of Mexico and the Dominican Republic. While there is a large number of workers in Zhangpu amber, only two species are represented. The systematics and morphology of the tribe Meliponini is outlined, including a revision to terms of orientation and direction when discussing surfaces and features of appendages, all in order to better discuss the traits of the fossils as well as place them into a broader context in the global systematics of stingless bees. The two amber species are representative of two Old World genera of Meliponini: Tetragonula Moure and Austroplebeia Moure. While the former is widespread across southern Asia, Malesia, Papuasia, and Australia, the latter is today known only from New Guinea and Australia. Neither genus occurs in the environs of Zhangpu today. Tetragonula (Tetragonula) florilega Engel, new species, is a generally typical species of the subgenus although it intermingles traits otherwise found in two large species groups of non-Australian Tetragonula s.str. The species of Austroplebeia from Zhangpu is sufficiently distinct to place in a new subgenus, Anteplebeina Engel. Austroplebeia (Anteplebeina) fujianica Engel, new species, shares a long list of character states with Austroplebeia s.str., including the presence of yellow maculation on the face, mesoscutum, mesoscutellum, and metepisternum, found only in this clade among Asiatic Meliponini. Nonetheless, the species differs in the length of the malar space and various features of wing venation. Keys are provided to the genera in Zhangpu amber and the subgenera of both genera. The diversity of stingless bees in amber is discussed, as well as the presence of these two fossils in the Middle Miocene of mainland Asia in relation to prior divergence time estimates, phylogenetic relationships, as well as the paleogeography of the region and potential biogeographic hypotheses. The biological association of stingless bees with resins, particularly the collection of dipterocarp resins, is discussed as Zhangpu amber is a Class II resin likely produced by an extinct species of Dipterocarpaceae (Malvales). Also discussed are the ecological preferences of modern Tetragonula and Austroplebeia relative to the reconstructed paleoenvironment of the Zhangpu amber rainforest. Emendations to the classification of Meliponini are appended, with the following new taxa proposed: Atrichotrigona Engel, new subgenus of Axestotrigona Moure; Lispotrigona V.H. Gonzalez & Engel, new subgenus of Nannotrigona Cockerell; Asperplebeia Engel, new genus; Nanoplebeia Engel, new subgenus of Plebeia Schwarz; Aphaneuropsis Engel, Koilotrigona Engel, Necrotrigona Engel, Dichrotrigona Engel, Nostotrigona Engel, Ktinotrofia Engel, all new subgenera of Trigona Jurine; Chapadapis Engel, new subgenus of Schwarziana Moure. The following higher groups are also established: Hypotrigonina Engel, new sutribe; Heterotrigonitae Engel, new infratribe; Trigoniscitae Engel, new infratribe.

@article{doi1017161jomi10515734,
    author = "Engel, Michael S. and Herhold, Hollister W. and Davis, Steven R. and Wáng, Bó and Thomas, Jennifer C.",
    title = "Stingless bees in Miocene amber of southeastern China (Hymenoptera: Apidae)",
    year = "2021",
    journal = "Journal of Melittology",
    abstract = "Among the many inclusions from the exceptionally rich fossiliferous amber of Zhangpu, China (Middle Miocene: Langhian), stingless bees (Apinae: Meliponini) are particularly common, analogous to the merely slightly older amber sites of Mexico and the Dominican Republic. While there is a large number of workers in Zhangpu amber, only two species are represented. The systematics and morphology of the tribe Meliponini is outlined, including a revision to terms of orientation and direction when discussing surfaces and features of appendages, all in order to better discuss the traits of the fossils as well as place them into a broader context in the global systematics of stingless bees. The two amber species are representative of two Old World genera of Meliponini: Tetragonula Moure and Austroplebeia Moure. While the former is widespread across southern Asia, Malesia, Papuasia, and Australia, the latter is today known only from New Guinea and Australia. Neither genus occurs in the environs of Zhangpu today. Tetragonula (Tetragonula) florilega Engel, new species, is a generally typical species of the subgenus although it intermingles traits otherwise found in two large species groups of non-Australian Tetragonula s.str. The species of Austroplebeia from Zhangpu is sufficiently distinct to place in a new subgenus, Anteplebeina Engel. Austroplebeia (Anteplebeina) fujianica Engel, new species, shares a long list of character states with Austroplebeia s.str., including the presence of yellow maculation on the face, mesoscutum, mesoscutellum, and metepisternum, found only in this clade among Asiatic Meliponini. Nonetheless, the species differs in the length of the malar space and various features of wing venation. Keys are provided to the genera in Zhangpu amber and the subgenera of both genera. The diversity of stingless bees in amber is discussed, as well as the presence of these two fossils in the Middle Miocene of mainland Asia in relation to prior divergence time estimates, phylogenetic relationships, as well as the paleogeography of the region and potential biogeographic hypotheses. The biological association of stingless bees with resins, particularly the collection of dipterocarp resins, is discussed as Zhangpu amber is a Class II resin likely produced by an extinct species of Dipterocarpaceae (Malvales). Also discussed are the ecological preferences of modern Tetragonula and Austroplebeia relative to the reconstructed paleoenvironment of the Zhangpu amber rainforest. Emendations to the classification of Meliponini are appended, with the following new taxa proposed: Atrichotrigona Engel, new subgenus of Axestotrigona Moure; Lispotrigona V.H. Gonzalez \& Engel, new subgenus of Nannotrigona Cockerell; Asperplebeia Engel, new genus; Nanoplebeia Engel, new subgenus of Plebeia Schwarz; Aphaneuropsis Engel, Koilotrigona Engel, Necrotrigona Engel, Dichrotrigona Engel, Nostotrigona Engel, Ktinotrofia Engel, all new subgenera of Trigona Jurine; Chapadapis Engel, new subgenus of Schwarziana Moure. The following higher groups are also established: Hypotrigonina Engel, new sutribe; Heterotrigonitae Engel, new infratribe; Trigoniscitae Engel, new infratribe.",
    url = "https://doi.org/10.17161/jom.i105.15734",
    doi = "10.17161/jom.i105.15734",
    openalex = "W3198169050",
    references = "barden2020fossil, doi101126sciadvabg0625"
}

Reduced precipitation in the Miocene triggered the geographic contraction of rainforest ecosystems around the world. In Australia, this change was particularly pronounced; mesic rainforest ecosystems that once dominated the landscape transformed into the shrublands, grasslands, and deserts of today. A lack of well-preserved fossils has made it difficult to understand the nature of Australian ecosystems before the aridification. Here, we report on an exceptionally well-preserved rainforest biota from New South Wales, Australia. This Konservat-Lagerstätte hosts a rich diversity of microfossils, plants, insects, spiders, and vertebrate remains preserved in goethite. We document evidence for several species interactions including predation, parasitism, and pollination. The fossils are indicative of an oxbow lake in a mesic rainforest and suggest that rainforest distributions have shifted since the Miocene. The variety of fossils preserved, together with high fidelity of preservation, allows for unprecedented insights into the mesic ecosystems that dominated Australia during the Miocene.

@article{doi101126sciadvabm1406,
    author = "McCurry, Matthew R. and Cantrill, David J. and Smith, Patrick M. and Beattie, Robert and Dettmann, Mary E. and Baranov, Viktor and Magee, C. W. and Nguyen, Jacqueline M. T. and Forster, Marnie and Hinde, Jack and Pogson, R. E. and Wang, Helen and Marjo, Christopher E. and Vasconcelos, Paulo and Frese, Michael",
    title = "A Lagerstätte from Australia provides insight into the nature of Miocene mesic ecosystems",
    year = "2022",
    journal = "Science Advances",
    abstract = "Reduced precipitation in the Miocene triggered the geographic contraction of rainforest ecosystems around the world. In Australia, this change was particularly pronounced; mesic rainforest ecosystems that once dominated the landscape transformed into the shrublands, grasslands, and deserts of today. A lack of well-preserved fossils has made it difficult to understand the nature of Australian ecosystems before the aridification. Here, we report on an exceptionally well-preserved rainforest biota from New South Wales, Australia. This Konservat-Lagerstätte hosts a rich diversity of microfossils, plants, insects, spiders, and vertebrate remains preserved in goethite. We document evidence for several species interactions including predation, parasitism, and pollination. The fossils are indicative of an oxbow lake in a mesic rainforest and suggest that rainforest distributions have shifted since the Miocene. The variety of fossils preserved, together with high fidelity of preservation, allows for unprecedented insights into the mesic ecosystems that dominated Australia during the Miocene.",
    url = "https://doi.org/10.1126/sciadv.abm1406",
    doi = "10.1126/sciadv.abm1406",
    openalex = "W4205371699",
    references = "doi101126sciadvabg0625"
}

decline in the Miocene were recently shown not to be associated with major ice volume expansion, challenging a fundamental paradigm in the functioning of the Antarctic cryosphere. Here, we explore Miocene ice-ocean-climate interactions by presenting a multi-proxy reconstruction of subtropical front migration, bottom water temperature and global ice volume change, using dinoflagellate cyst biogeography, benthic foraminiferal clumped isotopes from offshore Tasmania. We report an equatorward frontal migration and strengthening, concurrent with surface and deep ocean cooling but absence of ice volume change in the mid-late-Miocene. To reconcile these counterintuitive findings, we argue based on new ice sheet modelling that the Antarctic ice sheet progressively lowered in height while expanding seawards, to maintain a stable volume. This can be achieved with rigorous intervention in model precipitation regimes on Antarctica and ice-induced ocean cooling and requires rethinking the interactions between ice, ocean and climate.

@article{doi101038s41467023431064,
    author = "Hou, Suning and Stap, Lennert B. and Paul, Ryan and Nelissen, Mei and Hoem, Frida S. and Ziegler, Martin and Sluijs, Appy and Sangiorgi, Francesca and Bijl, Peter K.",
    title = "Reconciling Southern Ocean fronts equatorward migration with minor Antarctic ice volume change during Miocene cooling",
    year = "2023",
    journal = "Nature Communications",
    abstract = "decline in the Miocene were recently shown not to be associated with major ice volume expansion, challenging a fundamental paradigm in the functioning of the Antarctic cryosphere. Here, we explore Miocene ice-ocean-climate interactions by presenting a multi-proxy reconstruction of subtropical front migration, bottom water temperature and global ice volume change, using dinoflagellate cyst biogeography, benthic foraminiferal clumped isotopes from offshore Tasmania. We report an equatorward frontal migration and strengthening, concurrent with surface and deep ocean cooling but absence of ice volume change in the mid-late-Miocene. To reconcile these counterintuitive findings, we argue based on new ice sheet modelling that the Antarctic ice sheet progressively lowered in height while expanding seawards, to maintain a stable volume. This can be achieved with rigorous intervention in model precipitation regimes on Antarctica and ice-induced ocean cooling and requires rethinking the interactions between ice, ocean and climate.",
    url = "https://doi.org/10.1038/s41467-023-43106-4",
    doi = "10.1038/s41467-023-43106-4",
    openalex = "W4388532251",
    references = "doi1010292022rg000775"
}

Abstract Studying monsoon dynamics during past warm time periods such as the Miocene Climatic Optimum (MCO; ∼16.9–14.5 Ma) could greatly aid in better projecting monsoon intensity, in the context of future greenhouse warming. However, studies on regional MCO temperature change and its effect on the monsoons during this time period are lacking. Here, we present the first high‐resolution, low‐latitude record of sea surface temperature (SST) and paleoceanographic change covering the Miocene Climatic Optimum, in the eastern equatorial Atlantic, at Ocean Drilling Program Site 959, based on TEX 86 paleothermometry. SSTs were ∼1.5°C warmer at the onset of the MCO (16.9 Ma) relative to the pre‐MCO (∼18.3–17.7 Ma). This warming was accompanied by a transient increase in %total organic carbon. Prior to the MCO, sediment composition, geochemical proxy data as well as dinoflagellate cyst assemblages imply a productive surface ocean at Site 959. Immediately following the MCO onset (∼16.9–16.5 Ma), we record an intensification of the West African Monsoon (WAM) characterized by higher amplitude variability in all proxy records on precession to obliquity timescales. We interpret increased orbital‐scale SST, biogenic Ba and dinocyst assemblage variability to represent intensification of equatorial upwelling, forced by the WAM strength. Furthermore, higher SSTs during eccentricity maxima correlate to increased relative abundances of the warm and stratification‐favoring dinocyst Polysphaeridium zoharyi, during periods of low WAM intensity. Finally, while long‐term SSTs decline toward the middle Miocene, maximum SSTs and Polysphaeridium zoharyi abundances occur during MCO peak warming at ∼15.6 Ma.

@article{doi1010292023pa004767,
    author = "Wubben, Evi and Spiering, Bianca and Veenstra, Tjerk and Bos, Remco and Wang, Zongyi and van Dijk, Joost and Raffi, Isabella and Witkowski, Jakub and Hilgen, F.J. and Peterse, Francien and Sangiorgi, Francesca and Sluijs, Appy",
    title = "Tropical Warming and Intensification of the West African Monsoon During the Miocene Climatic Optimum",
    year = "2024",
    journal = "Paleoceanography and Paleoclimatology",
    abstract = "Abstract Studying monsoon dynamics during past warm time periods such as the Miocene Climatic Optimum (MCO; ∼16.9–14.5 Ma) could greatly aid in better projecting monsoon intensity, in the context of future greenhouse warming. However, studies on regional MCO temperature change and its effect on the monsoons during this time period are lacking. Here, we present the first high‐resolution, low‐latitude record of sea surface temperature (SST) and paleoceanographic change covering the Miocene Climatic Optimum, in the eastern equatorial Atlantic, at Ocean Drilling Program Site 959, based on TEX 86 paleothermometry. SSTs were ∼1.5°C warmer at the onset of the MCO (16.9 Ma) relative to the pre‐MCO (∼18.3–17.7 Ma). This warming was accompanied by a transient increase in \%total organic carbon. Prior to the MCO, sediment composition, geochemical proxy data as well as dinoflagellate cyst assemblages imply a productive surface ocean at Site 959. Immediately following the MCO onset (∼16.9–16.5 Ma), we record an intensification of the West African Monsoon (WAM) characterized by higher amplitude variability in all proxy records on precession to obliquity timescales. We interpret increased orbital‐scale SST, biogenic Ba and dinocyst assemblage variability to represent intensification of equatorial upwelling, forced by the WAM strength. Furthermore, higher SSTs during eccentricity maxima correlate to increased relative abundances of the warm and stratification‐favoring dinocyst Polysphaeridium zoharyi, during periods of low WAM intensity. Finally, while long‐term SSTs decline toward the middle Miocene, maximum SSTs and Polysphaeridium zoharyi abundances occur during MCO peak warming at ∼15.6 Ma.",
    url = "https://doi.org/10.1029/2023pa004767",
    doi = "10.1029/2023pa004767",
    openalex = "W4396738433",
    references = "doi1010292022rg000775, doi102973odpprocsr1590181998"
}