An asteroid that crashed into the earth 65 million years ago may not have been the cause of the dinosaurs' extinction, a group of researchers are arguing. Instead, that impact may have been just a prelude to the main event, when a wave of volcanic eruptions spewed out massive clouds of sulfur dioxide, clouding the air and bringing showers of acid rain. The researchers are basing their theory on studies of an area in India called the Deccan Traps, which was convulsed with volcanic activity around 65 million years ago.
At least four waves of massive eruptions spread successive sheets of thick basalt across the land for more than 500 miles, and they piled into a plateau more than 11,000 feet high over thousands of years [San Francisco Chronicle].
The new research on the Deccan Traps volcanoes, announced at the ongoing meeting of the American Geophysical Union, are the first ...