Impact event Chicxulub Crater. This crater is centered on the Yucatán Peninsula of Mexico and was discovered by Tony Camargo and Glen Pentfield while working as geophysicists for the Mexican oil company PEMEX. What they reported as a circular feature later turned out to be a crater estimated to be in diameter. This convinced the vast majority of scientists that this extinction resulted from a point event that is most probably an extraterrestrial impact and not from increased volcanism and climate change (which would spread its main effect over a much longer time period). Although there is now general agreement that there
Rochechouart crater From the morphology of the crater floor and the impact deposit it is clear the initial crater is much larger than the 12 km zone where outcrops the remnants of the crater fill deposit. In the # 4–25 km diameter range, terrestrial impact craters are developing a central high, such as Boltysh crater, a 24 km impact crater in Ukraine. Like Rochechouart, Boltysh formed exclusively in crystalline basement. The crater is buried yet the deeper structure is known through numerous drill cores and geophysical investigation undertaken during the Soviet period in the search of hydrocarbons. The central high at Boltysh