Palaeoenvironmental reconstruction of the Sarmatian (Middle Miocene) Central Paratethys based on palaeontological and geochernical analyses of foraminifera, ostracods, gastropods and rodents
| Autor: | Vincent Balter, Christophe Lécuyer, Miiklos Monostori, Emoke Toth, Ágnes Görög, Pierre Moissette |
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| Přispěvatelé: | HAS-HNHM Research Group for Paleontology, Hungarian Natural History Museum (Magyar Természettudományi Múzeum), Department of Palaeontology, Eötvös Loránd University (ELTE), PaleoEnvironnements et PaleobioSphere (PEPS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Sciences de la Terre (LST), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL) |
| Jazyk: | angličtina |
| Rok vydání: | 2010 |
| Předmět: |
Mediterranean climate
Delta 010506 paleontology [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Structural basin 010502 geochemistry & geophysics 01 natural sciences Isotopes of oxygen Foraminifera chemistry.chemical_compound Paleontology 14. Life underwater 0105 earth and related environmental sciences geochemistry Hungary biology Stable isotope ratio foraminifera Geology biology.organism_classification Middle Miocene chemistry ostracods Carbonate Transgressive |
| Zdroj: | Geological Magazine Geological Magazine, Cambridge University Press (CUP), 2010, 147 (2), pp.299-314. ⟨10.1017/S0016756809990203⟩ Geological Magazine, 2010, 147 (2), pp.299-314. ⟨10.1017/S0016756809990203⟩ |
| ISSN: | 0016-7568 1469-5081 |
| Popis: | Palaeoenvironmental changes in the upper Middle Miocene Central Paratethys were reconstructed by using qualitative and quantitative palaeontological analyses of foraminifera and ostracods, coupled with trace elemental (Mg/Ca) and stable isotope (δ18O and δ13C) analyses of their carbonate skeletons and of gastropod shells. Mean annual air temperatures were estimated using the oxygen isotope composition of contemporaneous rodent teeth. The studied aquatic fossils come from two boreholes in the Zsámbék Basin (northern central Hungary), while the terrestrial ones are from localities in NE Hungary and E Romania. In the studied Sarmatian successions, three zones could be distinguished, based on palaeontological and geochemical results. At the Badenian/Sarmatian boundary, faunal diversity decreased markedly. In the lower zone a transgressive event culminated in a seawater incursion into the semi-open basin system of the Central Paratethys. Stable bottom-water temperature (~15 °C) and variable salinities (20–32 ‰) are estimated for the Early Sarmatian Sea. The faunal changes (notably a strong reduction in biodiversity) occurring at the boundary between the lower and the middle zone can be explained by a sea-level highstand with dysoxic conditions. A relative sea-level fall is documented at the end of this middle zone. After a short regressive event, a marine connection between the Paratethys and the Mediterranean was established at the beginning of the upper zone. This is indicated by an increased microfaunal diversity and the re-appearance of marine Badenian ostracods and foraminifera, which are completely absent from the older Sarmatian series. During the upper zone, the temperatures and salinities are estimated to have fluctuated from 15 °C to 21 °C and from 15 ‰ to 43 ‰, respectively. |
| Databáze: | OpenAIRE |
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