Hugh Pickens writes "According to recent research, huge amounts of sulphur dioxide released by volcanic eruptions may have had more to do with wiping out dinosaurs than the meteorite strike at Chicxulub on Mexico's Yucatán Peninsula. Marine sediments drilled from the Chicxulub crater have revealed that that the mass extinctions occurred 300,000 years after Chicxulub hit Earth. The Deccan volcanism was a long cumulative process that released vast amounts of greenhouse gases into the atmosphere. '"On land it must have been 7-8 degrees warmer," says Princeton University paleontologist Gerta Keller. "The Chicxulub impact alone could not have caused the mass extinction, because this impact predates the mass extinction."' Keller also postulates a second larger and still unidentified meteor strike after Chicxulub, that left the famous extraterrestrial layer of iridium found in rocks worldwide and pushed earth's ecosystem over the brink. But where's the crater? "I wish I knew," says Keller."