Chicxulub crater

The Chicxulub crater is an impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is offshore, but the crater is named after the onshore inland community of Chicxulub Pueblo rather than the larger coastal town of Chicxulub Puerto. It was formed slightly over 66 million years ago when an asteroid, about ten kilometers (six miles) in diameter, struck Earth. The crater is estimated to be 200 kilometers (120 miles) in diameter and is buried to a depth of about 1 kilometer (0.62 miles) beneath younger sedimentary rocks. It is one of the largest impact structures on Earth, alongside the much older Sudbury and Vredefort impact structures, and the only one whose peak ring is intact and directly accessible for scientific research.

The crater was discovered by Antonio Camargo and Glen Penfield, geophysicists who had been looking for petroleum in the Yucatán Peninsula during the late 1970s. Penfield was initially unable to obtain evidence that the geological feature was a crater and gave up his search. Later, through contact with Alan R. Hildebrand in 1990, Penfield obtained samples that suggested it was an impact feature. Evidence for the crater's impact origin includes shocked quartz, a gravity anomaly, and tektites in surrounding areas.