Differentiation of the sulfides in the Basal Zone of the Stillwater Complex, Montana

Norman J. Page; F.O. Simon

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USGS · 70232577

Differentiation of the sulfides in the Basal Zone of the Stillwater Complex, Montana

Norman J. Page·F.O. Simon

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Abstract

Chemical leaching and analysis of the sulflde portion of rocks from a section of the Basal zone of the Stillwater Complex demonstrate that mole fractions of nickel, copper, cobalt, and sulfur in the sulfldes show trends and repeating patterns when plotted against stratigraphic position. These patterns are attributed to differentiation of immiscible sulflde liquids probably in response to differentiation of basaltic magma. Changes in composition of the immiscible sulflde liquids could most readily take place during the collection of the sulflde from the basaltic magma or during the crystallization of the sulflde liquid to the present assemblages of minerals.

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Journal of Research of the U.S. Geological Survey Article

Source-reported bounding extent: 45.07739974122637° to 45.729191061299915° latitude; -110.55541992187499° to -109.0338134765625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Norman J. Page, F.O. Simon. 1978. Differentiation of the sulfides in the Basal Zone of the Stillwater Complex, Montana. https://pubs.usgs.gov/publication/70232577

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