Impact Hypothesis
Haraldur Sigurdsson and Steve Carey have long been interested in explosive volcanism and have been actively involved in the debate about the extinctions associated with the end of the Cretaceous period and beginning of the Paleocene (the Cretaceous/Tertiary boundary). . . In their research, they showed that features of this important transition period could not be explained by explosive volcanism. With Steve D'Hondt [and John King], they focused instead on field work in the Caribbean to look at the relationship between a major asteroid impact in Mexico at the end of the Cretaceous and the oceanographic and evolutionary events at the same time. Their work culminated in an ODP [Ocean Drilling Program] leg (Leg 165) in the Caribbean which drilled holes to test the hypothesis that the Mexican asteroid impact generated ocean tsunamis and other effects that could be seen in the sediments. . . The cruise was enormously successful and drilled the first complete sequence of sediments that showed the fallout from the collision debris itself and a "Strangelove Ocean" devoid of almost all microscopic life because of the sulfuric acid generated from the volcanic gas interaction with the atmosphere.
---Margaret Leinen Maritimes, Summer 1997