Cretaceous–Paleogene boundary had been that no documented crater matched the event. This was not a lethal blow to the theory; while the crater resulting from the impact would have been larger than in diameter, Earth's geological processes hide or destroy craters over time. 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
Tookoonooka crater Tookoonooka crater Tookoonooka is a large meteorite impact crater (astrobleme) situated in South West Queensland, Australia. It lies deeply buried within Mesozoic sedimentary rocks of the Eromanga Basin and is not visible at the surface. Tookoonooka was discovered using seismic data collected during routine petroleum exploration and first reported in a publication in 1989, with proof of the impact theory coming from the discovery of shocked quartz in drill core. Estimates of the crater diameter range from to . The impact occurred during deposition of the Cretaceous Cadna-owie Formation, the age of which is variously estimated at being between 123–133