Uranium, thorium, and mercury distribution through the evolution of the McDermitt Caldera complex

James J. Rytuba; W.K. Conrad; Richard K. Glanzman

doi:10.3133/ofr79541

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Uranium, thorium, and mercury distribution through the evolution of the McDermitt Caldera complex

James J. Rytuba·W.K. Conrad·Richard K. Glanzman

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Abstract

The McDermitt caldera complex developed over a period of 5 m.y. years during which ash-flow tuff sheets anomalous in mercury, uranium, and thorium were emplaced. The moat portions of the caldera complex were subsequently filled with tuffaceous sediments. Late in the caldera development near-surface intrusives and domes were emplaced along the margins of the complex and mineralized with uranium. Seven large hydrothermal systems developed at this time and formed large areas of alteration within the caldera-fill volcanics and sediments. Five of the altered zones are associated with economic concentrations of uranium, and or mercury.

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Source-reported bounding extent: 41.64726212881368° to 42.09210825254959° latitude; -118.20190429687501° to -117.81463623046875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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James J. Rytuba, W.K. Conrad, Richard K. Glanzman. 1979. Uranium, thorium, and mercury distribution through the evolution of the McDermitt Caldera complex. https://doi.org/10.3133/ofr79541

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