Fission-track dating of pumice from the KBS Tuff, East Rudolf, Kenya

A.J. Hurford; A.J.W. Gleadow; C. W. Naeser

doi:10.1038/263738a0

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Fission-track dating of pumice from the KBS Tuff, East Rudolf, Kenya

A.J. Hurford·A.J.W. Gleadow·C. W. Naeser

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Abstract

Fission-track dating of zircon separated from two pumice samples from the KBS Tuff in the Koobi Fora Formation, in Area 131, East Rudolf, Kenya, gives an age of 2.44±0.08 Myr for the eruption of the pumice. This result is compatible with the previously published K–Ar and 40 Ar/ 39 Ar age spectrum estimate of 2.61±0.26 Myr for the KBS Tuff in Area 105, but differs from the more recently published K–Ar date of 1.82±0.04 Myr for the KBS Tuff in Area 131. This study does not support the suggestion that pumice cobbles of different ages occur in the KBS Tuff

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Source-reported bounding extent: -4.67677° to 5.506° latitude; 33.89357° to 41.85508° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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A.J. Hurford, A.J.W. Gleadow, C. W. Naeser. 1976. Fission-track dating of pumice from the KBS Tuff, East Rudolf, Kenya. https://doi.org/10.1038/263738a0

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