Report Sez Volcanic Gases Killed The Dinosaurs

["Richard W. Travsky" <rtravsky@uwyo.edu>]

http://www.nature.com/news/2007/071031/full/news.2007.205.html
Gas may be to blame for extinction
Contrarian theory argues against meteorite killing dinosaurs.

A worldwide burp of volcanic gases caused the mass extinction that wiped 
out dinosaurs and other creatures 65 million years ago, says research 
reported this week. Its the latest argument from a group that has been 
trying for some time to discredit the leading theory  that a meteorite 
striking Mexico led to the mass die-offs.

The international team says that we should instead blame plumes of 
climate-altering gas given off by monumental lava flows that stretch 
hundreds of kilometres across India.

The Deccan Traps, as theyre called, have been suspected before of having 
some sort of global impact around the end of the Cretaceous period and the 
beginning of the Tertiary, known as the KT boundary. Earlier research had 
dated the main outburst of the lava flows as occurring within 800,000 
years of the boundary. But the new analysis uses tiny plankton fossils, 
trapped between lava layers, to date the flow to the boundary itself.

This is the first time we can link the main phase of the Deccan Traps to 
the mass extinction, says team leader Gerta Keller, a palaeontologist at 
Princeton University in New Jersey. Keller and Thierry Adatte of the 
University of Neuchtel in Switzerland presented their research on 30 
October in Denver, Colorado, at the annual meeting of the Geological 
Society of America.
...