The Terrestrial Impact Record: From Geochemical Confirmation to Planetary Defense
The recognition of impact craters on the Earth is difficult due to active geological and atmospheric processes. To confirm impact craters on Earth, detailed mineralogical, petrographic, and geochemical studies are needed; this led to the identification of ~200 terrestrial impact craters. The first impact evidence dates to ca. 3.4 Ga; the oldest preserved impact structure is 2.02 Gyr old. Despite limited information about the early impact record we know that impacts had severe effects on the geological and biological evolution on Earth. Current efforts on planetary defense are also noted.
Christian Koeberl is full professor of geosciences at the University of Vienna; from 2010 to 2020 was director general of the Natural History Museum Vienna. He is full member of the Austrian Academy of Sciences, where he heads the Committee on Geosciences. Koeberl studied chemistry, physics, and astronomy at the TU Vienna and Univ. Vienna, and obtained his PhD in 1983 at the University of Graz. He has published over 500 peer-reviewed papers and about 20 books; he has received, among other honors, the Barringer-Medal of the Meteoritical Society, and asteroid 15963 is named in his honor "Koeberl".