Oxygen isotopes of East Asian dinosaurs reveal exceptionally cold Early Cretaceous climates | INSTITUT DE PHYSIQUE DU GLOBE DE PARIS

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  Oxygen isotopes of East Asian dinosaurs reveal exceptionally cold Early Cretaceous climates

Type de publication:

Journal Article

Source:

Proceedings of the National Academy of Sciences of the United States of America, Volume 108, Ticket 13, p.5179-5183 (2011)

ISBN:

0027-8424

Numéro d'accès:

WOS:000288894800013

Mots-clés:

UMR 7154 ; Paléomagnétisme ; vertebrate phosphate ∣ oxygen isotopes ∣ paleoclimate

Résumé:

Early Cretaceous vertebrate assemblages from East Asia and particularly the Jehol Biota of northeastern China flourished during a period of highly debated climatic history. While the unique characters of these continental faunas have been the subject of various speculations about their biogeographic history, little attention has been paid to their possible climatic causes. Here we address this question using the oxygen isotope composition of apatite phosphate (δ18Op) from various reptile remains recovered from China, Thailand, and Japan. δ18Op values indicate that cold terrestrial climates prevailed at least in this part of Asia during the Barremian— early Albian interval. Estimated mean air temperatures of about 10  4 °C at midlatitudes (∼42 °N) correspond to present day cool temperate climatic conditions. Such low temperatures are in agreement with previous reports of cold marine temperatures during this part of the Early Cretaceous, as well as with the widespread occurrence of the temperate fossil wood genus Xenoxylon and the absence of thermophilic reptiles such as crocodilians in northeastern China. The unique character of the Jehol Biota is thus not only the result of its evolutionary and biogeographical history but is also due to rather cold local climatic conditions linked to the paleolatitudinal position of northeastern China and globalicehouse climates that prevailed during this part of the Early Cretaceous.

Notes:

Times Cited: 0This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1011369108/-/DCSupplemental.