Platinum, palladium, and rhodium in volcanic and plutonic rocks from the Gravina-Nutzotin belt, Alaska

Norman J. Page; Henry C. Berg; Joseph Haffty

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USGS · 70164406

Platinum, palladium, and rhodium in volcanic and plutonic rocks from the Gravina-Nutzotin belt, Alaska

Norman J. Page·Henry C. Berg·Joseph Haffty

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Abstract

The Gravina-Nutzotin belt of Middle (?) Jurassic to middle Cretaceous sedimentary and volcanic rocks in south and southeastern Alaska includes concentrically zoned ultramafic complexes known to contain platinum-group metals. Previous isotopic, petrologic, and geologic studies suggested a close relation in time and space between the volcanic rocks and the ultramafic complexes. Interpretation of 40 analyses for platinum, palladium, and rhodium in volcanic and plutonic rocks of the belt indicates a strong geochemical correlation between the two groups of rocks and is in support of their being cogenetic either from directly connected magma chambers and flows or indirectly by selective concentration processes from similar mantle material.

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

Source-reported bounding extent: 54.5° to 59° latitude; -136° to -130° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Norman J. Page, Henry C. Berg, Joseph Haffty. 1977. Platinum, palladium, and rhodium in volcanic and plutonic rocks from the Gravina-Nutzotin belt, Alaska. https://pubs.usgs.gov/publication/70164406

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