What killed off those dinosaurs? Was it the impact of a meteorite? Or gases released by enormous lava flows in India? Both suggestions have been argued for years. New data indicates that it may have been both! And the events may have been related.
A meteorite is widely recognized to have impacted northern Yucatan, Mexico, at the Cretaceous-Paleogene (KPg) boundary about 66 million years ago. Now Renne and his co-authors in the journal Science have documented a major increase in the volume of lava flows of the Deccan Traps [basaltic lavas] of India — on the other side of the globe — at essentially the same time. They suggest that seismic waves from the impact traveled literally around the world and reorganized the “plumbing” of the already erupting Traps, thus promoting much larger eruptions with massive amounts of poisonous carbon and sulfur dioxide gases released into the atmosphere.
In other words, the impact helped “open the tap” for tremendous amounts of molten rock to reach Earth’s surface. Either event alone probably could have wiped out the dinosaurs; but both so close in time? It was a veritable one-two knockout punch.
More on the Deccan Traps in the video below: