Potassium-argon and lead-alpha ages of plutonic rocks, Bokan Mountain area, Alaska

M. A. Lanphere; E.M. MacKevett; T. W. Stern

doi:10.1126/science.145.3633.705

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Potassium-argon and lead-alpha ages of plutonic rocks, Bokan Mountain area, Alaska

M. A. Lanphere·E.M. MacKevett·T. W. Stern

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Abstract

Most of the granitic rocks in the Bokan Mountain area, southeastern Alaska, are early Paleozoic (probably Ordovician) judged by potassium-argon and lead-alpha age measurements. The Bokan Mountain Granite, the youngest intrusive unit in the area, belongs to a Mesozoic plutonic episode. These age measurements are the first direct evidence for the emplacement of early Paleozoic granitic intrusive rocks close to the Pacific margin of North America.

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Source-reported bounding extent: 54.87458540920767° to 54.93905290945244° latitude; -132.18901692768776° to -132.12085621356115° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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M. A. Lanphere, E.M. MacKevett, T. W. Stern. 1964. Potassium-argon and lead-alpha ages of plutonic rocks, Bokan Mountain area, Alaska. https://doi.org/10.1126/science.145.3633.705

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