Catherine Corrigan Catherine Corrigan Catherine Margaret Corrigan (born 1972), often known as Cari Corrigan, is an American scientist best known as a curator of the meteorite collection at the Smithsonian Institution. She is a scientist in the Department of Mineral Science at the National Museum of Natural History. Corrigan obtained a Bachelor of Science in 1995 and a Master of Science in 1998, both in Geology at Michigan State University. Her master's thesis was titled "The Composition of Impact Breccias from the Chicxulub Impact Crater, Yucatan Peninsula, Yucatan, Mexico". She later earned a Ph.D in Planetary Science at Case Western Reserve University
Chicxulub crater Bakker, argue that such an impact would have killed frogs as well as dinosaurs, yet the frogs survived the extinction event. Gerta Keller of Princeton University argues that recent core samples from Chicxulub prove the impact occurred about 300,000 years "before" the mass extinction, and thus could not have been the causal factor. However, this conclusion is unsupported by radioactive dating and sedimentology. The main evidence of such an impact, besides the crater itself, is contained in a thin layer of clay present in the K–Pg boundary across the world. In the late 1970s, the Alvarezes and colleagues reported that