Geologic framework of nonmarine cretaceous-tertiary boundary sites, Raton Basin, New Mexico and Colorado

C. L. Pillmore; R.H. Tschudy; C. J. Orth; J. S. Gilmore; J.D. Knight

doi:10.1126/science.223.4641.1180

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Geologic framework of nonmarine cretaceous-tertiary boundary sites, Raton Basin, New Mexico and Colorado

C. L. Pillmore·R.H. Tschudy·C. J. Orth·J. S. Gilmore·J.D. Knight

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Abstract

Indium concentrations are anomalously high at the palynological Cretaceous-Tertiary boundary in fluvial sedimentary rocks of the lower part of the Raton Formation at several localities in the Raton Basin of New Mexico and Colorado. The iridium anomaly is associated with a thin bed of kaolinitic claystone in a discontinuous carbonaceous shale and coal sequence.

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Source-reported bounding extent: 36.10694002086515° to 38.2774455058005° latitude; -108.82659135029371° to -103.80036694062991° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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C. L. Pillmore, R.H. Tschudy, C. J. Orth, J. S. Gilmore, J.D. Knight. 1984. Geologic framework of nonmarine cretaceous-tertiary boundary sites, Raton Basin, New Mexico and Colorado. https://doi.org/10.1126/science.223.4641.1180

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