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
Chesapeake Bay impact crater Chesapeake Bay impact crater The Chesapeake Bay impact crater was formed by a bolide that impacted the eastern shore of North America about 35.5 ± 0.3 million years ago, in the late Eocene epoch. It is one of the best-preserved "wet-target" or marine impact craters, and the largest known impact crater in the U.S. Continued slumping of sediments over the rubble of the crater has helped shape the Chesapeake Bay. During the warm late Eocene, sea levels were high, and the Tidewater region of Virginia lay in the coastal shallows. The shore of eastern North America, about where Richmond, Virginia