40Ar/39Ar age of Cretaceous-Tertiary boundary tektites from Haiti

G. A. Izett; G. B. Dalrymple; L.W. Snee

doi:10.1126/science.252.5012.1539

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40Ar/39Ar age of Cretaceous-Tertiary boundary tektites from Haiti

G. A. Izett·G. B. Dalrymple·L.W. Snee

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Abstract

40 Ar/ 39 Ar dating of tektites discovered recently in Cretaceous-Tertiary (K-T) boundary marine sedimentary rocks on Haiti indicates that the K-T boundary and impact event are coeval at 64.5 ± 0.1 million years ago. Sanidine from a bentonite that lies directly above the K-T boundary in continental, coal-bearing, sedimentary rocks of Montana was also dated and has a 40 Ar/ 39 Ar age of 64.6 ± 0.2 million years ago, which is indistinguishable statistically from the age of the tektites.

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Source-reported bounding extent: 17.96750074358431° to 20.16346469034243° latitude; -74.73829701924586° to -71.67095321747738° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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G. A. Izett, G. B. Dalrymple, L.W. Snee. 1991. 40Ar/39Ar age of Cretaceous-Tertiary boundary tektites from Haiti. https://doi.org/10.1126/science.252.5012.1539

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