Geochemistry of the end-Permian extinction event in Austria and Italy: No evidence for an extraterrestrial component
- 1Department of Geological Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
- 2Division of Geological and Planetary Sciences, MS 170-25, California Institute of Technology, Pasadena, California 91125, USA
- 3Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543-1541, USA
- 4Planetary and Space Sciences Research Institute, Open University, Milton Keynes MK7 6AA, UK
Abstract
The end-Permian mass extinction (251 Ma) was the largest in Earth's history, and the great extent of biospheric perturbation is recorded as dramatic shifts in carbon isotope ratios of sedimentary materials. Both terrestrial and extraterrestrial events are commonly invoked as causative mechanisms for the crisis, and the primary reason for the event remains the subject of controversy. Geochemical indicators sensitive to the influence of extraterrestrial material involve platinum group elements and osmium and helium isotope ratios. Analyses of extinction levels in two sections from Austria and Italy reveal no evidence of an extraterrestrial impact. The end-Permian crisis, it appears, was a homegrown catastrophe.
Footnotes
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↵*christian.koeberlunivie.ac.at; farleygps.caltech.edu; behrenbrinkwhoi.edu; m.a.sephtonopen.ac.uk
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↵GSA Data Repository item 2004166, Figures DR1–DR2 and Tables DR1–DR3, is available online at www.geosociety.org/pubs/ft2004.htm, or on request from editinggeosociety.org or Documents Secretary, GSA, P.O. Box 9140, Boulder, CO 80301-9140, USA.
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- Accepted August 30, 2004.
- Received June 23, 2004.
- Revision received August 30, 2004.
- Geological Society of America
