Asteroid killed off the dinos, concludes international scientific panel

WASHINGTON - A panel of 41 international experts has determined that the Cretaceous-Tertiary mass extinction, which wiped out the dinosaurs and more than half of species on Earth 65 million years ago, was caused by an asteroid colliding with Earth and not massive volcanic activity.

The panel reviewed 20 years’ worth of research to determine the cause of the Cretaceous-Tertiary (KT) extinction.

The extinction wiped out more than half of all species on the planet, including the dinosaurs, bird-like pterosaurs and large marine reptiles, clearing the way for mammals to become the dominant species on Earth.

The review of the evidence shows that the extinction was caused by a massive asteroid slamming into Earth at Chicxulub in Mexico.

The asteroid, which was around 15 kilometres wide, is believed to have hit Earth with a force one billion times more powerful than the atomic bomb at Hiroshima.

It would have blasted material at high velocity into the atmosphere, triggering a chain of events that caused a global winter, wiping out much of life on Earth in a matter of days.

Scientists have previously argued about whether the extinction was caused by the asteroid or by volcanic activity in the Deccan Traps in India, where there were a series of super volcanic eruptions that lasted approximately 1.5 million years.

These eruptions spewed 1,100,000 km of basalt lava across the Deccan Traps, which would have been enough to fill the Black Sea twice, and were thought to have caused a cooling of the atmosphere and acid rain on a global scale.

In the new study, scientists analyzed the work of palaeontologists, geochemists, climate modellers, geophysicists and sedimentologists who have been collecting evidence about the KT extinction over the last 20 years.

Geological records show that the event that triggered the extinction destroyed marine and land ecosystems rapidly, according to the researchers, who conclude that the Chicxulub asteroid impact is the only plausible explanation for this.

According to Dr Joanna Morgan, co-author of the review from the Department of Earth Science and Engineering at Imperial College London, “We now have great confidence that an asteroid was the cause of the KT extinction. This triggered large-scale fires, earthquakes measuring more than 10 on the Richter scale, and continental landslides, which created tsunamis.”

“However, the final nail in the coffin for the dinosaurs happened when blasted material was ejected at high velocity into the atmosphere. This shrouded the planet in darkness and caused a global winter, killing off many species that couldn’t adapt to this hellish environment,” she said. (ANI)