Volcanos may have contributed to dinosaur extinction, UMN study says

The study could shed light on the long-debated role of the meteorite impact in the mass extinction.

by Wesley Hortenbach

Volcanic eruptions caused by the meteorite impact that killed the dinosaurs may have contributed to the mass extinction, according to new research from the University of Minnesota.

The study, published this month, could shed light on the long-debated role of the Chicxulub meteorite in the dinosaur extinction 66.5 million years ago.

University postdoctoral researcher Joseph Byrnes analyzed seafloor data and found excess amounts of mass — former lava flows — on the Indian and Pacific Ocean seafloors that formed within 1 million years of the Chicxulub impact. This points to volcanic eruptions triggered by the impact, Byrnes said.

While earth scientists understand how volcanos erupt, the reasons why remain a mystery, said senior author Leif Karlstrom, assistant professor of earth sciences at the University of Oregon.

This study also suggests that seismic waves can cause volcanic activity.

“This was a hypothesis that was really pushing the edges of what we knew about mantle dynamics. We were able to fulfill this prediction of that theory [of mass extinction], and a lot of people were really surprised,” Byrnes said.

The researchers have also proposed that the mass extinction wasn’t the result of one single factor, but might have been a result of both the asteroid and the volcanic activity.

The role of the asteroid in the mass extinction is still a subject of controversy among scientists. Kent Kirkby, teaching professor in the College of Science and Engineering, said scientists often try to solve controversial ideas by combining them. If that doesn’t work, experts develop new ideas.  

Scientists are also working to understand the mass extinction on a smaller level to better grasp why individual species died out, Kirkby said. This is an especially useful endeavor today, when the Earth is experiencing one of the largest mass extinctions in its history, he said.

“Looking at mass extinction in the past record isn’t just an interesting tale. It’s actually possibly adding insights to our own actions and implications on present ecosystems,” Kirkby said.

Byrnes said a desire to better understand the world as a whole motivates his research.

“These historical events move and excite people,” he said. “That’s why I do it. Lots of little kids want to know these answers. It’s something that gets humans going, just wanting to know.”