2004 Denver Annual Meeting (November 7–10, 2004)
Paper No. 133-9
Presentation Time: 10:40 AM-11:00 AM


SCHINDLER, Eberhard, Forschungsinstitut Senckenberg, Senckenberganlage 25, Frankfurt am Main D-60325 Germany, eberhard.schindler@senckenberg.de

During the Late Devonian two major events affected the marine fauna – the Kellwasser (KW) Event near the Frasnian/Famennian (mid-Late Devonian) stage boundary and the Hangenberg Event close to the Devonian/Carboniferous boundary. Both can be traced globally and the debate on their nature – especially their cause(s) – is vivid, long-lasting, and on-going. Although clearly focused on the KW Event, a number of arguments arising from the enormous amount of research during previous decades can be used to infer to general aspects of event-related patterns.

Among the questions that must be considered are those of what may have been causing globally distributed events in the Late Devonian, what was the “normal” situation present when the “unusual” cause(s) affected the biota, which groups of organisms were most affected, were events selective, and did a given event have negative or positive effects on evolutionary rates? Some of the results taken from a vast number of studies have to be evaluated, including theorized extraterrestrial impacts, climatic deterioration, plate tectonic reorganization, and oceanographic changes. Further, of prime interest are questions regarding ‘extraterrestrial’ vs. ‘Earth-bound’ mechanisms and ‘single’ vs. ‘multi-causal’ events.

2004 Denver Annual Meeting (November 7–10, 2004)
General Information for this Meeting
Session No. 133
Pre-Mesozoic Impacts: Their Effect on Ocean Geochemistry, Magnetic Polarity, Climate Change, and Organic Evolution
Colorado Convention Center: Ballroom 4
8:00 AM-12:00 PM, Tuesday, 9 November 2004

Geological Society of America Abstracts with Programs, Vol. 36, No. 5, p. 322

© Copyright 2004 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.