LEICESTER, England, April 2 (UPI) -- British researchers said they have found massive volcanic eruptions and asteroid impacts happened almost simultaneously over the past 300 million years.
As a result, BBC News Online reported Friday, the researchers think the chances asteroid impacts and huge bouts of volcanism coincided randomly to cause mass extinctions may be greater than previously imagined.
The researchers, from the University of Leicester, conducted statistical tests to determine the probability of such catastrophic events happening at the same time in Earth's history. They found evidence of both volcanism and cataclysmic impact happening at the same time 65 million years ago, when the dinosaurs disappeared from the fossil record. The impact that created the 120-mile-wide impact crater at Chicxulub in Mexico is generally thought to have played a major part in this extinction.
Some experts think the flood basalts known as the Deccan Traps in India also could have caused the extinctions, because the gases released in this volcanic event would have resulted in major climate changes.
The researchers argue that because impacts and flood basalts occur more frequently than mass extinctions, it is unlikely the two phenomena bring about mass extinctions on their own, so mass extinctions may be triggered only when the two events occur together.
