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D. F. Siems

Publications and source records attributed to D. F. Siems.

At least 73 records · Page 4Linked to original sources
USGS1984

Reconnaissance geochemical map of the Mount Henry Roadless Area, Lincoln County, Montana

A geochemical survey was conducted in the Mount Henry Roadless Area, Kootenai National Forest, Lincoln County, Mont. by the U.S. Geological Survey during the summer of 1981. The sampling and analytical programs were designed to locate mineralized zones in outcrops or in rocks buried at shallow depth. The geochemical results should be evaluated in context with geological and geophysical results. Possible types of mineralization, as judged from occurrences in nearby areas where the rocks are similar to those in the study area, include strata-bound copper-silver occurrences in rocks of the Ravalli Group, specifically the Burke and Revett Formations; the less probable lead-zinc massive sulfide deposits of the Sullivan-type in the pre-Ravalli (middle Prichard Formation); potential metal-enriched, sulfide vein systems; and gold-bearing veins or placer occurrences. All samples collected for this study are plotted on the map. Element symbols shown at sample sites indicate an anomalous concentration for that element at the site. Tables 1–3 list the values of selected elements determined to be critical for a mineral evaluation of this particular geologic setting. All analytical results, including those selected for this report, are given in a U.S. Geological Survey Open-File report (Siems and others, 1983).

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