Scientists: “tandem” asteroid wiped out the dinosaurs and volcanoes – RIA Novosti

1/2

© Photo: Mark Richards, UC Berkeley

© Photo: Paul Renne, Berkeley Geochronology Center

MOSCOW, October 2 – RIA Novosti . Geologists have specified the age of lava emission on the Deccan plateau, which took place at about the same time as dinosaurs that helped them to prove that the outbreak of volcanic activity on a par with the fall of the asteroid were to blame for the extinction of Mesozoic fauna, according to a paper published in the journal Science.

Most paleontologists and geologists now believe that the last mass extinction on Earth, which occurred 65.5 million years ago was caused by the asteroid impact, leaving a giant 300 km Chicxulub crater in southern Mexico. In his fall, no one doubts, but its role in the extinction of the dinosaurs and marine reptiles is still a matter of debate.

For example, in 1989, now known paleontologist Mark Richards of the University of California at Berkeley (USA) presented an alternative explanation the extinction of the dinosaurs – in his view, the reason for their disappearance served as a massive outpouring of magma and volcanic eruptions on the Deccan plateau site of the modern India, occurred at about the same time. According to his calculations, such events should occur every 20-30 million years because of rising hot magma flows, so-called “plume” from the bowels of the earth’s surface.

Richards and his colleagues found support for these calculations , traveled to India and accurately measuring the age of the rocks which allegedly poured out on the ground plateau Dean during the extinction of the dinosaurs. Measure the age of the rocks in different layers and regions Dean ratio of shares of rare isotopes of argon, scientists have tried to figure out how much magma poured out immediately before and after the fall of the asteroid.

© Photo: NASA / JPL-Caltech

As it turned out, volcanoes Dean erupted about two-thirds of magma covering today is a plateau for 50 thousand years before and 50 thousand years after the fall of the asteroid. This is because the rate of eruptions increased at almost twice the cause of what is believed to be the authors of the article, was the “shaking” of rocks in the Earth after the formation of the crater Chicxulub.

“As our dating You can be almost certain that the outbreak of volcanism and asteroid occurred some 50,000 years before the extinction, and therefore makes no sense to speculate about which of them was the “killer” of the dinosaurs – and both, obviously, contributed to their extinction. We are not even able to share their influence on the atmosphere and other parts of the Earth. It all happened at the same time “, – concludes the other author, Paul Renne (Paul Renne) from the University of California at Berkeley (USA).