Long-period orbital control on middle Miocene global cooling: Integrated stratigraphy and astronomical tuning of the Blue Clay Formation on Malta

Abstract One of the richest occurrences of fossil Mammalia in Europe was discovered in 1834 in the Helvetian (middle Miocene) deposits of Sansan in southwestern France. Nearly all groups are represented, from Chiroptera to proboscidians. The extraordinary richness of the deposit makes statistical treatment possible. Although many changes occurred in the marshy to lacustrine environment during the time of deposition, as reflected in clays, marls, limestones, and molasse, the amplitude of the changes never was large enough to destroy the balance that prevailed through the Helvetian in the area. Restudy of the fossil materials collected over a long period of time resulted in some nomenclatural changes.

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Clay mineralogy of the Tertiary onshore and offshore strata of the British Isles

Clay Minerals ◽

10.1180/0009855064110195 ◽

2006 ◽

Vol 41 (1) ◽

pp. 5-46 ◽

Cited By ~ 12

Author(s):

J. M. Huggett ◽

R. W. O'B. Knox

Keyword(s):

North Sea ◽

Volcanic Ash ◽

Middle Miocene ◽

Clay Mineralogy ◽

British Isles ◽

Subsequent Increase ◽

The North ◽

Clay Deposits ◽

The North Sea ◽

Clay Formation

AbstractTertiary sediments are of restricted occurrence in the onshore British Isles but occur extensively offshore, attaining thicknesses of ~4 km in the Faroe—Shetland Basin and ~3 km in the North Sea Basin. Clay mineral stratigraphic studies of the North Sea Paleocene to Lower Miocene successions show a dominance of smectite (and smectite-rich illite-smectite) with minor illite, kaolin and chlorite. Abundant smectite in the Paleocene and Eocene reflects alteration of volcanic ash derived from pyroclastic activity associated with the opening of the North Atlantic between Greenland and Europe. However, the persistence of high smectite into the Oligocene and Middle Miocene indicates that smectite-rich soils on adjacent land areas may also have been an important source of detrital clays. An upwards change to illite-dominated assemblages in the Middle Miocene reflects higher rates of erosion and detrital clay supply, with a subsequent increase in chlorite reflecting climatic cooling. The persistence of smectite-rich assemblages to depths of >3000 m in the offshore indicates little burial-related diagenesis within the mudstone succession, possibly as a consequence of over-pressuring. Despite the importance of Paleocene and Eocene sandstones as hydrocarbon reservoirs in the North Sea and Faroe-Shetland basins, there are few published details of the authigenic clays. The principal clay cements in these sandstones are kaolin and chlorite, with only minor illite reported.The offshore successions provide a valuable background to the interpretation of the more intensively studied, but stratigraphically less complete, onshore Tertiary successions. The most extensive onshore successions occur in the London and Hampshire basins where sediments of Paleocene to earliest Oligocene age are preserved. Here clay assemblages are dominated by illite and smectite with subordinate kaolin and chlorite. The relatively large smectite content of these successions is also attributed primarily to the alteration of volcanic ash. Associated non-smectitic clays are largely detrital in origin and sourced from areas to the west, with reworking of laterites and “china clay” deposits developed over Cornish granites. Authigenic clays include glauconite (sensu lato), early diagenetic kaolin that has replaced muscovite (principally in the London Clay Formation of the London Basin) and smectite that has replaced ash. Pedogenesis has extensively modified the assemblages in the Reading Formation and Solent Group. Tertiary sediments are largely missing from onshore northern and western Britain, but clays and sands of Eocene and Oligocene age are locally preserved in small fault-bounded basins. Here, clay assemblages are dominated by kaolin with minor illite.

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Integrated stratigraphy and 40Ar/39Ar chronology of the early to middle Miocene Upper Freshwater Molasse in western Bavaria (Germany)

International Journal of Earth Sciences ◽

10.1007/s00531-009-0475-8 ◽

2009 ◽

Vol 99 (8) ◽

pp. 1859-1886 ◽

Cited By ~ 40

Author(s):

Hayfaa Abdul Aziz ◽

Madelaine Böhme ◽

Alexander Rocholl ◽

Jerome Prieto ◽

Jan R. Wijbrans ◽

...

Keyword(s):

Middle Miocene ◽

Upper Freshwater Molasse ◽

Integrated Stratigraphy

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Middle Miocene oxygen minimum zone expansion offshore West Africa: Evidence for global cooling precursor events

Geology ◽

10.1130/g30070a.1 ◽

2009 ◽

Vol 37 (8) ◽

pp. 699-702 ◽

Cited By ~ 11

Author(s):

S. Kender ◽

V.L. Peck ◽

R.W. Jones ◽

M.A. Kaminski

Keyword(s):

West Africa ◽

Middle Miocene ◽

Oxygen Minimum Zone ◽

Global Cooling ◽

Minimum Zone ◽

Oxygen Minimum

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Late Cenozoic continuous aridification in the western Qaidam Basin: evidence from sporopollen records

Climate of the Past Discussions ◽

10.5194/cpd-9-1485-2013 ◽

2013 ◽

Vol 9 (2) ◽

pp. 1485-1508 ◽

Cited By ~ 10

Author(s):

Y. F. Miao ◽

X. M. Fang ◽

F. L. Wu ◽

M. T. Cai ◽

C. H. Song ◽

...

Keyword(s):

Tibetan Plateau ◽

Middle Miocene ◽

Qaidam Basin ◽

East Asian ◽

The Tibetan Plateau ◽

Late Cenozoic ◽

Plateau Uplift ◽

Western Qaidam Basin ◽

Global Cooling ◽

Tibetan Plateau Uplift

Abstract. Cenozoic climate changes in inner Asia provide a basis for understanding linkages between global cooling, the Tibetan Plateau uplift, and possibly the development of the East Asian monsoon. Based on the compiled palynological results from the western Qaidam Basin, this study reconstructed an 18 Ma record of changing vegetation and paleoclimates since the middle Miocene. Thermophilic taxa percentages were highest between 18 and 14 Ma and decreased after 14 Ma, corresponding closely with the Middle Miocene Climatic Optimum (MMCO) between 18 and 14 Ma and the following global climatic cooling. After 3.6 Ma, the thermophilic taxa percentages further decreased, showing the inevitable relations with the ice-sheets enlargement in the North Hemisphere. During the same period of time, the increase in xerophytic taxa percentages and decrease in conifers percentages imply aridification in both the basin and surrounding mountains since 18 Ma. These results indicate that global cooling mainly controlled the climate change from a relative warm-wet stage to a cold-dry stage during the late Cenozoic at the western Qaidam Basin, and that the Tibetan Plateau uplift also contributed in contrast to the East Asian summer monsoon.

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Regional trends in clay mineral fluxes to the Queensland margin and ties to middle Miocene global cooling

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/j.palaeo.2005.09.010 ◽

2006 ◽

Vol 233 (3-4) ◽

pp. 204-224 ◽

Cited By ~ 4

Author(s):

Cédric M. John ◽

Thierry Adatte ◽

Maria Mutti

Keyword(s):

Clay Mineral ◽

Middle Miocene ◽

Regional Trends ◽

Global Cooling

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Long-period eccentricity control on sedimentary sequences in the continental Madrid Basin (middle Miocene, Spain)

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2009.11.011 ◽

2010 ◽

Vol 289 (1-2) ◽

pp. 220-231 ◽

Cited By ~ 34

Author(s):

Hemmo A. Abels ◽

Hayfaa Abdul Aziz ◽

Wout Krijgsman ◽

Sander J.B. Smeets ◽

Frederik J. Hilgen

Keyword(s):

Middle Miocene ◽

Long Period ◽

Sedimentary Sequences

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Neogene amphibians and reptiles (Caudata, Anura, Gekotta, Lacertilia, Testudines) from south of Western Siberia, Russia and Northeastern Kazakhstan

10.7287/peerj.preprints.2365 ◽

2016 ◽

Author(s):

Davit Vasilyan ◽

Vladimir Zazhigin ◽

Madelaine Böhme

Keyword(s):

Northern Hemisphere ◽

Middle Miocene ◽

Western Siberia ◽

Bufo Bufo ◽

Early Miocene ◽

Early Pleistocene ◽

Published Data ◽

Molecular Clocks ◽

Western Asia ◽

Global Cooling

Background. Now-a-day territory of Western Siberia has the poorest diversity of amphibians and reptiles within the Palaearctic Realm, influenced by unfavourable climate. Less is known about the origin and emergence of it. Aside from better-explored European Neogene records of amphibians and reptiles, the Neogene herpetofauna of Western Asia is understudied. The few available studies on amphibian and reptile fossil assemblages need critical reviews and new interpretations considering the latest knowledge of the European record. The comparison with European record will provide data on palaeobiogeographic affiliations of the region as well as origin and emergence of the now-a-day fauna of Western Siberia. Beside these, a study providing overview about the earliest occurences of certain amphibian linages, that can be used for the calibration of the molecular clocks, is missing. Methods and Results. The amphibian and reptile fauna from over 40 Western Siberian, Russia and Northeastern Kazakhian localities ranging from Middle Miocene to Early Pleistocene has been studied. In the study the published data has been considered and critically reviewed and newly interpreted. More then 50 amphibian and reptile taxa has been identified belonging to families Hynobiidae, Cryptobranchidae, Salamandridae, Palaeobatrachidae, Bombinatoridae, Pelobatidae, Hylidae, Bufonidae, Ranidae, Gekkonidae, Lacertidae and Emydidae. Palaeobiogeographic analysis for those group has been done. For 12 localities, palaeoprecipitation values have been estimated using the bioclimatic analysis of herpetofaunal assemblage. Conclusions. The Neogene assemblage of Westren Sibera is dominated by groups (Palaeobatrachidae, Bombina, Hyla, Bufo bufo) with European affinities. A small part of assemblage includes Eastern Palaearctic taxa (e.g. Hynobiidae, Tylototriton, Bufotes viridis, R. arvalis). For several taxa (e.g. Mioproteus, Hyla, Bombina) the Western Siberian records of represent the most east Eurasian records of these groups. The most divers faunas are found in the Middle Miocene, whereas the poorest towards Early Pleistocene. This tendency could be referred to the progressive global cooling of the climate in Northern Hemisphere. Our results showed higher-amplitude changes of precipitation development in Western Siberia from Early Miocene to Pliocene, than earlier assumed.

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