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USGS · 70011847

Mixed-layer kerolite/stevensite from the Amargosa Desert, Nevada

Dennis D. Eberl·Blair F. Jones·Hani N. Khoury
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Abstract

Mixed-layer clays composed of randomly interstratified kerolite/stevensite occur as lake and/or spring deposits of probable Pliocene and Pleistocene age in the Amargosa Desert of southern Nevada, U.S.A. The percentage of expandable layers of these clays, determined from computer-simulated X-ray diffractograms, ranges from almost 0 to about 80%. This range in expandabilities most likely results from differences in solution chemistry and/or temperature at the time of formation. An average structural formula for the purest clay (sample P-7), a clay with about 70% expandable layers, is: [(Mg 2.72 Al 0.07 Fe 0.03 Li 0.09 )(Si 3.96 Al 0.04 )O 10 (OH) 0.2 ] -0.21 [X + 0.21 ] +0.21 The data suggest that talc, kerolite, and stevensite form a continuous structural series based on layer charge.

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Dennis D. Eberl, Blair F. Jones, Hani N. Khoury. 2024-04-02. Mixed-layer kerolite/stevensite from the Amargosa Desert, Nevada. https://doi.org/10.1346/ccmn.1982.0300501

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