Chicxulub crater Chicxulub crater The Chicxulub crater (; ) is an impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is located near the town of Chicxulub, after which the crater is named. It was formed by a large asteroid or comet about in diameter, the Chicxulub impactor, striking the Earth. The date of the impact coincides precisely with the Cretaceous–Paleogene boundary (K–Pg boundary), slightly less than 66 million years ago, and a widely accepted theory is that worldwide climate disruption from the event was the cause of the Cretaceous–Paleogene extinction event, a mass extinction in which 75% of plant
Liverpool crater event to form the rim. Flat-lying and non-deformed sandstone that must have been deposited after the impact event is exposed within the crater's center. Because the crater is quite well preserved, it can be argued that it was buried by younger sedimentary rock soon after the impact event; this younger rock has now been mostly eroded away except in the crater center. The crater-filling sandstone was originally thought to be of Cretaceous age, leading to the Cretaceous age listed for the crater in older literature sources. But more recent studies suggest that the infilling rock is more likely to be