Jan Smit is a paleontologist who specializes in abrupt changes in the geological record.  After the discovery of an end-Cretaceous surge deposit in North Dakota, he was part of the team that pieced together the striking evidence it contained, particularly its perfectly preserved fossils and tiny glass spherules called tektites.  He describes how this led to a detailed picture of the dramatic events that unfolded within an hour or two following the asteroid impact.
Jan Smit is Emeritus Professor of Event Stratigraphy at the Free University of Amsterdam.  Initially a paleontologist studying planktonic foraminifera, he became intrigued by what appeared to be extremely sudden events in the fossil record, especially at the boundary between the Cretaceous and the Paleogene, known as the KT boundary.
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