Massive volcanic eruptions set the stage for dinosaurs’ demise

Science Focus

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It's now widely accepted that the impact of an asteroid at Chicxulub in Mexico's Yucatan region finished off any dinosaurs that we don't currently refer to as birds, while triggering a mass extinction that wiped out a lot of other species. But that hasn't ended the debate regarding the dynamics of the extinction event, with other ecological influences getting consideration as contributing to the dinosaurs' vulnerability.

One potential contributor that's hard to overlook is situated in western India: the Deccan Traps. These enormous deposits are built of layer upon layer of volcanic rock, suggesting a series of flood eruptions took place over thousands of years. These eruptions happened suspiciously close to the start of the mass extinction—close enough that some researchers argued that it was the eruptions that killed off the dinosaurs. There was, after all, precedent; the eruptions that formed the Siberian Traps have been blamed for a mass extinction that was so severe, it's known as the The Great Dying.

To help settle the issue, an international team of researchers has gone back and obtained the most precise dates for the eruptions yet. The dates show that the eruptions started nearly a quarter-million years before the onset of the mass extinction but continued for roughly 750,000 years, meaning they spanned the extinction event. This supports the idea that the eruptions helped set the stage for the end of the dinosaurs.

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