Bedout: An End-Permian Impact Site Off-Shore Northwestern Australia

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0341972BeckerThe cause of the catastrophic mass extinction at the end of the Permian has been the focus of considerable debate. The PIs and others have presented evidence that a major extraterrestrial impact likely triggered a sequence of events leading to the destruction of 90% of marine taxa. The debate regarding the existence and possible effect of a large end-Permian impact strongly resembles the debate associated with the Cretaceous-Tertiary (K/T) impact prior to the identification, confirmation, and recognition of the Chicxulub impact site off the Yucatan Peninsula. Acceptance of a K/T impact increased dramatically with the discovery of the Chicxulub crater.The PIs believe they have preliminary evidence that core taken from the Bedout High, a large subcircular structure located offshore northwestern Australia is, in fact, an impact breccia as it contains shocked minerals, glasses, and geochemical signatures unlike typical terrestrial volcanism. The preliminary age of the core material is ~253 Ma. In addition, other geochemical and petrological evidence genetically links the breccia found in the Bedout structure to other end-Permian impact deposits worldwide. This award will support a workshop in Australia to provide an international forum to present the available geologic and geophysical data about the offshore Bedout structure, the geochemical and petrologic characteristics of its core, and to discuss possible collaborative studies needed to confirm the properties and characteristics of this possible end-Permian crater structure. The workshop will involve both Australian and American scientists and students, as well as others who are familiar with and can critically evaluate the available data. This workshop will provide the framework for a Bedout Working Group whose purpose will be to initiate, foster, and coordinate multi-disciplinary, international studies of the Bedout structure and its possible relationship to the end-Permian mass extinction event.