What Earth Was Like After the Dinosaurs Disappeared

Sixty-six million years ago, a rock the size of Mount Everest slammed into the Yucatan Peninsula at roughly 64,000 kilometers per hour. The energy released was equivalent to billions of nuclear bombs. The rock itself didn't so much land as vaporize, along with an enormous chunk of the Earth's crust, in a fraction of a second. The crater left behind, Chicxulub, stretched roughly 180 kilometers in diameter and was buried under subsequent layers of rock and sediment for millions of years before scientists figured out it was there at all.

The Immediate Catastrophe

The first seconds after impact triggered earthquakes above magnitude 10 on the Richter scale—orders of magnitude more powerful than anything recorded in modern history. The entire crust of the Earth rang like a struck bell. Tsunamis hundreds of meters tall reshaped coastlines across the Gulf of Mexico, leaving chaotic layers of jumbled sediment that have been found in Texas, Alabama, and Mississippi. Volcanoes in what is now India, the Deccan Traps, had already been erupting sporadically for thousands of years before the impact; the seismic shock may have dramatically accelerated that activity.