The demise of the dinosaurs may have been the result of a coordinated one-two punch.
Eruption activity in a volcanic region in present-day India appears to have increased around the time of the asteroid impact that preceded the Cretaceous extinction, scientists report in the Oct. 2 Science. The close timing between the two events leads the scientists to suggest that the impact could have triggered this volcanic shift.
Scientists have debated whether volcanic eruptions assisted the Chicxulub asteroid impact in wiping out over half of the planet’s species at the end of the Cretaceous period, roughly 66 million years ago. Previous studies showed that while eruptions in western India’s Deccan Traps began millions of years before the impact, volcanic activity surged closer to the time of the asteroid collision. In the new study, researchers report that during this volcanic shift, the amount of lava flooding the Deccan Traps roughly doubled, despite fewer overall eruptions. Scientists previously estimated that the impact and the lava surge were separated by under 100,000 years; the new study places the two events within around 50,000 years of each other.