New, Tighter Timeline Confirms Ancient Volcanism Aligned With Dinosaurs’ Extinction

A definitive geological timeline shows that a series of massive volcanic explosions 66 million years ago spewed enormous amounts of climate-altering gases into the atmosphere immediately before and during the extinction event that claimed Earth’s non-avian dinosaurs, according to new research from Princeton University.

A definitive geological timeline from Princeton University researchers shows that a series of massive eruptions 66 million years ago in a primeval volcanic range in western India known as the Deccan Traps played a role in the extinction event that claimed Earth's non-avian dinosaurs, and challenges the dominant theory that a meteorite impact was the sole cause of the extinction. Pictured above are the Deccan Traps near Mahabaleshwar, India. Gerta Keller/ Department of Geosciences

A definitive geological timeline shows that a series of massive volcanic explosions 66 million years ago spewed enormous amounts of climate-altering gases into the atmosphere immediately before and during the extinction event that claimed Earth’s non-avian dinosaurs, according to new research from Princeton University.

A primeval volcanic range in western India known as the Deccan Traps, which were once three times larger than France, began its main phase of eruptions roughly 250,000 years before the Cretaceous-Paleogene, or K-Pg, extinction event, the researchers report in the journal Science. For the next 750,000 years, the volcanoes unleashed more than 1.1 million cubic kilometers (264,000 cubic miles) of lava. The main phase of eruptions comprised about 80-90 percent of the total volume of the Deccan Traps’ lava flow and followed a substantially weaker first phase that began about 1 million years earlier.

The researchers suggest that the Deccan Traps eruptions and the meteorite impact near present-day Chicxulub, Mexico, need to be considered together when studying and modeling the Cretaceous-Paleogene extinction event. The main eruption phases for the Deccan Traps (in brown), which were once three times larger than France, began roughly 250,000 years before the extinction event, the researchers found. For the next 750,000 years, the volcanoes unleashed more than 1.1 million cubic kilometers (264,000 cubic miles) of lava, which comprised about 80-90 percent of the total volume of the Deccan Traps' lava flow. The amount of carbon dioxide and sulfur dioxide the volcanoes poured out would have caused severe ecological fallout. Matilda Luk/ Princeton University