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
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