Early Cretaceous high latitude marine reptile assemblages from Southern Australia
Date
2006
Authors
Kear, Benjamin Philip
Schroeder, Natalie I.
Vickers-Rich, Patricia
Rich, Thomas H.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Paludicola, 2006; 5(4):200-205
Statement of Responsibility
Benjamin P. Kear, Natalie I. Schroeder, Patricia Vickers-Rich and Thomas H. Rich
Conference Name
Abstract
The Lower Cretaceous (Aptian-Albian) southern high latitude deposits of Australia have yielded a diverse range of marine
reptile fossils. Ichthyosaurs and at least five distinct plesiosaur taxa have been recorded. Most of the current marine reptile
specimens are derived from the predominantly Aptian Bulldog Shale and Wallumbilla Formation. These units, famous for
producing opal, represent shallow epicontinental marine depositional environments. Fragmentary plesiosaur remains have also
been recovered from high latitude non-marine deposits of the Wonthaggi, Eumeralla, and Griman Creek formations. These are
Aptian to middle Albian in age, and comprise fine-grained fluviatile/estuarine sediments laid down in inland rift valleys and
coastal flood plains near the Cretaceous southern polar circle. Estimates of palaeolatitude place most of southern Australia at
around 60º to 80º S during the late Early Cretaceous. Sedimentary structures, fossils, isotope data, and climatic modeling
indicate highly seasonal cool-cold conditions possibly with winter freezing. This contrasts markedly with climate regimes
typically tolerated by modern aquatic reptiles, but suggests that some Mesozoic forms may have possessed adaptations to cope
with low average water temperatures.
School/Discipline
School of Earth and Environmental Sciences
Dissertation Note
Provenance
Description
© by the Rochester Institute of Vertebrate Palaeontology