Scientists: Dinosaurs became extinct from the “double whammy” of the asteroid and volcanoes – Express-News

02.10 | 17:24

The theme of the extinction of dinosaurs long been a hot debate among scientists and non-scientific world led to the unanimous opinion.

The most common version is the fall of a giant asteroid near Yucatan Peninsula in modern Mexico, which occurred about 66 million years ago. According to supporters of this theory, the cosmic body blow was so strong that it caused a giant tsunami, fires and severe climate change, comparable to a nuclear winter. Proof of asteroid diameter Chicxulub crater is 180 kilometers. Also makes a convincing this version is that the disaster coincides with the end of the Cretaceous period and the mass extinction of animals.

But there is another theory that the mass death of animals was caused by prolonged volcanic eruptions around the globe, which, turn, led to a dramatic climate change.

Supporters of this theory were also strong evidence of the results of geological studies that confirm the anomalous volcanic activity that lasted for hundreds of thousands of years, with the extinction of animals.

Opponents, by the way, did not deny this fact, but at the same time trying to combine the two theories into one: that volcanic activity could provoke fallen asteroid that caused the shift of tectonic plates, which led to massive volcanic eruptions.

The new work of scientists from the University of California at Berkeley recognizes both theories.

A team of researchers led by Paul Renne, using argon-argon radioisotope dating, the age set of layers of ancient lava on the Deccan Plateau in western India. It turned out that the anomalous volcanic activity started about 173,000 years before the formation of the crater Chicxulub, and continued for at least 500 thousand years after the fall of the asteroid.

As a result of the study of individual lava flows, scientists have estimated that up to the collision of Earth with an asteroid volcanoes annually erupted about 400 million cubic meters of lava, but after 50 thousand years after the impact this volume increased to 900 million cubic meters.

«Based on the analysis of lava, we can be quite sure that, in principle, impossible to establish the difference between the two mechanisms murder: both phenomena occurred at the same time “- said Rennes.

Geologists, in turn, said that the fall of the asteroid abruptly changed the chemical composition of the rocks and spewed out the frequency of eruptions. All this for 500 thousand years hampered the restoration of life at the beginning of the Tertiary period.

Still, most scientists still tend to think of the main killer asteroid, as it remains unclear some questions in the theory of volcanoes.