An orientation soil survey at the Pebble Cu-Au-Mo porphyry deposit, Alaska

Steven M. Smith; Robert G. Eppinger; David L. Fey; Karen D. Kelley; S. A. Giles

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USGS · 70156383

An orientation soil survey at the Pebble Cu-Au-Mo porphyry deposit, Alaska

Steven M. Smith·Robert G. Eppinger·David L. Fey·Karen D. Kelley·S. A. Giles

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Abstract

Soil samples were collected in 2007 and 2008 along three traverses across the giant Pebble Cu-Au-Mo porphyry deposit. Within each soil pit, four subsamples were collected following recommended protocols for each of ten commonly-used and proprietary leach/digestion techniques. The significance of geochemical patterns generated by these techniques was classified by visual inspection of plots showing individual element concentration by each analytical method along the 2007 traverse. A simple matrix by element versus method, populated with a value based on the significance classification, provides a method for ranking the utility of methods and elements at this deposit. The interpretation of a complex multi-element dataset derived from multiple analytical techniques is challenging. An example of vanadium results from a single leach technique is used to illustrate the several possible interpretations of the data.

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Source-reported bounding extent: 59.88° to 59.92° latitude; -155.35° to -155.23° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Steven M. Smith, Robert G. Eppinger, David L. Fey, Karen D. Kelley, S. A. Giles. 2009. An orientation soil survey at the Pebble Cu-Au-Mo porphyry deposit, Alaska. https://pubs.usgs.gov/publication/70156383

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