Asteroid that killed the dinosaurs was more destructive than we thought

8 Feb 2018

Image: Marc Ward/Shutterstock

New research into the asteroid that killed off the dinosaurs has found that it also contributed to a global volcanic event on the ocean floor.

The Cretaceous period of 66m years ago was more violent than we possibly could have imagined just a few decades ago, particularly after new research has shed some light on just how destructive the asteroid that killed off the dinosaur was.

In a paper published to Science Advances, researchers from the University of Texas analysed the Chicxulub impact – as it is known – and found that, aside from the tidal wave and enormous amounts of ash deposited in the planet’s atmosphere, it triggered massive amounts of volcanic activity on ocean floors.

Writing in The Conversation, the researchers said that the impact created enormous seismic waves that travelled across the globe, driving magma out of the planet’s mantle and into the oceanic crust.

Importantly, this volcanic activity was found to not be connected to the massive Deccan Traps eruption that occurred in modern-day India around the same period.

To come to this conclusion, the research team of Leif Karlstrom and Joseph Byrnes had to search for clues in the mid-ocean ridges that expand several inches each year, by actually analysing the ridges for signs of any massive event.

Given the obvious challenges of reaching the ocean floor, the pair analysed detailed maps of the peaks and valleys using satellite imagery for signs of volcanic activity.

And, sure enough, they found two bumps in the Pacific and Indian Oceans, which sprang up in a million-year period at the time of the impact and contained up to 1m cubic kilometres of magma.

Seismic records

The time with the smallest structural anomalies on the sea floor – indicating 8pc more mass anomalies than on average – occurs at 66m years ago and coincides with the age of the Chicxulub meteorite impact. Graph: Byrnes and Karlstrom/Science Advances 2018; 4: eaao2994 (CC BY-ND)

More than a coincidence

The researchers claim it is more than coincidental that a series of eruptions occurred with more intensity than any other time in 100m years.

With this information, the researchers have now drawn up a new timeline showing that the apocalyptic events on Earth began with the Deccan Traps event, followed by the Chicxulub impact 250,000 years later.

This resulted in a period of accelerated volcanic activity lasting upwards of tens of thousands of years, caking the Earth in clay, resulting in the death of the dinosaurs.

With this new information, Karlstrom and Byrnes now want to find out if this volcanic activity alone was enough to wipe out the creatures.

“What is clear is that this new research points to global-scale connections between catastrophes – a good reminder that events happening on the other side of the planet can have effects felt everywhere,” the pair said.

Colm Gorey was a senior journalist with Silicon Republic