Peter D. Ward
The University of Washington
Seattle, Washington
2011-12 Tour Information
27-Feb Colorado School of Mines Golden CO
28-Feb Grand Junction Geo Grand Junction CO
1-Mar Western Michigan University Kalamazoo MI
2-Mar Michigan State University East Lansing MI
6-Mar CSPG Calgary Alberta
7-Mar Montana Geological Society Billings MT
GO TO: Biography
Abstract
The history of life is punctuated by five "major" mass extinctions. In recent years it has seemed that at least three, and perhaps all five were caused by extraterrestrial causes - from asteroid impacts to gamma ray bursts. New research, however, suggests that the Earth may have been a far worse enemy to its life than outer space has been. While the temporal coincidence of large body igneous provinces and mass extinction or mass depletion of life has long been noted, only recently have actual "kill" mechanisms become believable. In this talk the new understanding of mass extinctions will be presented – as will the question of whether or not the most probable cause – lowered oceanic oxygen levels as a consequence of reduced pole to equator temperature differentials - is of relevance to our own world.