Tephra layers of Blind Spring Valley and related upper Pliocene and Pleistocene tephra layers, California, Nevada, and Utah: Isotopic ages, correlation, and magnetostratigraphy

Andrei M. Sarna-Wojcicki; Marith C. Reheis; Malcolm S. Pringle; Robert J. Fleck; Doug Burbank; Charles E. Meyer; Janet L. Slate; Elmira Wan; James R. Budahn; Bennie Troxel; James P. Walker

doi:10.3133/pp1701

USGS · pp1701

Tephra layers of Blind Spring Valley and related upper Pliocene and Pleistocene tephra layers, California, Nevada, and Utah: Isotopic ages, correlation, and magnetostratigraphy

Andrei M. Sarna-Wojcicki·Marith C. Reheis·Malcolm S. Pringle·Robert J. Fleck·Doug Burbank·Charles E. Meyer·Janet L. Slate·Elmira Wan·James R. Budahn·Bennie Troxel·James P. Walker

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Abstract

Numerical ages have been determined for a stratigraphic sequence of silicic tephra layers exposed at the Cowan Pumice Mine in Blind Spring Valley, near Benton Hot Springs, east-central California, as well as at Chalk Cliffs, north of Bishop, Calif. The tephra layers at these sites were deposited after eruptions from nearby sources, most of them from near Glass Mountain, and some from unknown sources. The ages were determined primarily by the laser-fusion 40 Ar/ 39 Ar method, mostly on sanidine feldspar; two were determined by conventional K-Ar analysis on obsidian clasts.

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Source-reported bounding extent: 34.016241889667015° to 39.232253141714885° latitude; -124.71679687499999° to -113.3349609375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Andrei M. Sarna-Wojcicki, Marith C. Reheis, Malcolm S. Pringle, Robert J. Fleck, Doug Burbank, Charles E. Meyer, Janet L. Slate, Elmira Wan, James R. Budahn, Bennie Troxel, James P. Walker. 2005. Tephra layers of Blind Spring Valley and related upper Pliocene and Pleistocene tephra layers, California, Nevada, and Utah: Isotopic ages, correlation, and magnetostratigraphy. https://doi.org/10.3133/pp1701

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