@article{BougeoisDupontNivetdeRafelisetal.2018,
  author    = {Bougeois, Laurie and Dupont-Nivet, Guillaume and de Rafelis, Marc and Tindall, Julia C. and Proust, Jean-Noel and Reichart, Gert-Jan and de Nooijer, Lennart J. and Guo, Zhaojie and Ormukov, Cholponbelk},
  title     = {Asian monsoons and aridification response to Paleogene sea retreat and Neogene westerly shielding indicated by seasonality in Paratethys oysters},
  series = {Earth and planetary science letters},
  volume    = {485},
  journal   = {Earth and planetary science letters},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0012-821X},
  doi       = {10.1016/j.epsl.2017.12.036},
  pages     = {99 -- 110},
  year      = {2018},
  abstract  = {Asian climate patterns, characterised by highly seasonal monsoons and continentality, are thought to originate in the Eocene epoch (56 to 34 million years ago - Ma) in response to global climate, Tibetan Plateau uplift and the disappearance of the giant Proto-Paratethys sea formerly extending over Eurasia. The influence of this sea on Asian climate has hitherto not been constrained by proxy records despite being recognised as a major driver by climate models. We report here strongly seasonal records preserved in annual lamina of Eocene oysters from the Proto-Paratethys with sedimentological and numerical data showing that monsoons were not dampened by the sea and that aridification was modulated by westerly moisture sourced from the sea. Hot and arid summers despite the presence of the sea suggest a strong anticyclonic zone at Central Asian latitudes and an orographic effect from the emerging Tibetan Plateau. Westerly moisture precipitating during cold and wetter winters appear to have decreased in two steps. First in response to the late Eocene (34-37 Ma) sea retreat; second by the orogeny of the Tian Shan and Pamir ranges shielding the westerlies after 25 Ma. Paleogene sea retreat and Neogene westerly shielding thus provide two successive mechanisms forcing coeval Asian desertification and biotic crises.},
  language  = {en}
}
@article{BougeoisdeRafelisReichartetal.2016,
  author    = {Bougeois, Laurie and de Rafelis, Marc and Reichart, Gert-Jan and de Nooijer, Lennart J. and Dupont-Nivet, Guillaume},
  title     = {Mg/Ca in fossil oyster shells as palaeotemperature proxy, an example from the Palaeogene of Central Asia},
  series = {Palaeogeography, palaeoclimatology, palaeoecology : an international journal for the geo-sciences},
  volume    = {441},
  journal   = {Palaeogeography, palaeoclimatology, palaeoecology : an international journal for the geo-sciences},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0031-0182},
  doi       = {10.1016/j.palaeo.2015.09.052},
  pages     = {611 -- 626},
  year      = {2016},
  abstract  = {Fossil oyster shells are well-suited to provide palaeotemperature proxies from geologic to seasonal timescales due to their ubiquitous occurrence from Triassic to Quaternary sediments, the seasonal nature of their shell growth and their relative strong resistance to post-mortem alteration. However, the common use to translate calcitic oxygen isotopes into palaeotemperatures is challenged by uncertainties in accounting for past seawater delta O-18, especially in shallow coastal environment where oysters calcify. In principle, the Mg/Ca ratio in oyster shells can provide an alternative palaeothermometer. Several studies provided temperature calibrations for this potential proxy based on modem species, nevertheless their application to palaeo-studies remains hitherto unexplored. Here, we show that past temperature variability in seawater can be obtained from Mg/Ca analyses from selected fossil oyster species and specimens. High-resolution Mg/Ca profiles, combined with delta O-18, were obtained along 41 fossil oyster shells of seven different species from the Palaeogene Proto-Paratethys sea (Central Asia) found in similar as well as different depositional age and environments providing comparison. Suitable Mg/Ca profiles, defined by continuous cyclicity and reproducibility within one shell, are found to be consistent for specimens of the same species but differ systematically between species, implying a dominant species-specific effect on the Mg/Ca signal. Two species studied here (Ostrea (Turkostrea) strictiplicata and Sokolowia buhsii) provide an excellent proxy for palaeoclimate reconstruction from China to Europe in Palaeogene marine sediments. More generally, the protocol developed here can be applied to identify other fossil oyster species suitable for palaeoclimate reconstructions. (C) 2015 Elsevier B.V. All rights reserved.},
  language  = {en}
}