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3. The K-T ejecta deposits from Haiti, Colorado, and
Saskatchewan each came from the same target rock, of age
545 million to 550 million years, and each was shocked at
exactly the same time: 65 million years ago.
A. Since rocks 545 million to 550 million years in age are rare in
North America, and since the Chicxulub zircons themselves
give both that upper age and the 6 5-million-year lower age, the
K-T ejecta in Haiti, Colorado, and Saskatchewan almost
certainly came from the Chicxulub structure.
Thus the K-T zircons provide direct, noncircumstantial evidence
that Chicxulub is the K-T impact crater. This is no longer a fascinat-
ing speculation, but closely approaches the status of observational
fact. Today, those who doubt that Chicxulub is the long-sought crater
can be counted on one's fingers. Yes, a giant meteorite did strike the
earth at the end of the Cretaceous. But did it cause the K-T mass
extinction and the death of the dinosaurs?
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