An asteroid and volcano one-two combo killed the dinosaurs

2 Oct 2015

New research has shown the extinction of the dinosaurs was not just the result of a cataclysmic asteroid impact, but rather a one-two punch that followed up the strike with thousands of years of volcanic eruptions.

While the impact of an asteroid 66m years ago is known to have led to the extinction of the dinosaurs, the question as to whether it was the only contributor to their downfall has been a topic of debate.

According to the University of California Berkeley, for the last 35 years there have been two opposing theories that either downplayed or put forward the importance of the many volcanic eruptions that followed in what we now call India.

Now, however, new evidence from the Deccan Traps lava flows in India appears to show that following the catastrophic impact on our planet, the region’s volcanic activity doubled their eruptions within 50,000 years of the strike.

This, the researchers say, was enough to completely change the fabric of the volcanic chambers and ‘pipes’ that were deep beneath the ground.

Deccan India

The Deccan Traps east of Mumbai, India. Image via Mark Richards

With a one-two punch of an asteroid impact and vast quantities of volcanic material ejected into the atmosphere, Earth’s skies would have been choked of sunlight, sending many of the planet’s species into extinction.

After such a violent period, it is believed that it took life 500,000 years to recover from the point of time known as the KT boundary at the Cretaceous and the beginning of the Tertiary period when large land animals and many small sea creatures disappeared from the fossil record.

Publishing its findings in the journal Science, the team’s lead researcher Paul Renne said: “At the KT boundary, we see major changes in the volcanic system of the Deccan Traps, in terms of the rate at which eruptions were happening, the size of the eruptions, the volume of the eruptions and some aspects of the chemistry of the eruptions, which speaks to the actual processes by which the magmas were generated,” Renne said.

“All these things changed in a fundamental way, and increasingly it seems they happened right at the KT boundary. Our data don’t conclusively prove that the impact caused these changes, but the connection looks increasingly clear.”

Volcano eruption image via Shutterstock

Colm Gorey was a senior journalist with Silicon Republic