|Quadrangle map, 1:250,000-scale||CH|
|Quadrangle map, 1:63,360-scale||D-6|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This site is at an elevation of about 3,500 feet, approximately 0.6 mile north-northwest of the mouth of Big Jim Creek on Jim Creek. It is about 0.5 mile west of the center of section 13, T. 35 N., R. 11 W. The location is accurate to within a half mile.|
Geologic descriptionThis occurrence was originally described as galena and copper sulfides with malachite-azurite staining in Upper Devonian phyllite with some siltstone and sandstone (Brosgé and Reiser, 1964). Kurtak and others (2002) identified a 50-foot-wide zone of quartz veins that are exposed along strike for about 100 feet. There are two sets of veins; one parallel to the foliation of the phyllite host rock, and the other one crosscuts it. Both are deformed by post-mineralization folding. A sample of a 3-foot-wide quartz vein with chalcopyrite and a trace of galena contained 0.36 percent copper.
|Geologic map unit||(-149.954979879025, 67.8582911317134)|
|Mineral deposit model||Quartz vein with chalcopyrite.|
|Age of mineralization||Late Devonian or younger based on the age of the host rock.|
|Alteration of deposit||None noted.|
|Workings or exploration||Only limited sampling by government agencies.|
|Indication of production||None|
This occurrence is in the Gates of the Arctic National Park which is closed to prospecting and mining.MAS No. 0020310073
Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Chandalar and Wiseman quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-340, 205 p.
Cobb, E.H., and Cruz, E.L., 1983, Summaries of data and lists of references to metallic and selected nonmetallic mineral deposits in the Chandalar quadrangle, Alaska: U.S. Geological Survey Open-File Report 83-278, 91 p.
DeYoung, J.H., Jr., 1978, Mineral resources map of the Chandalar quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-878-B, 2 sheets, scale 1:250,000.
Kurtak, J.M., Klieforth, R.F., Clark, J.M., and Maclean, E.A., 2002, Mineral investigations in the Koyukuk mining district, northern Alaska, 2 vols.: Bureau of Land Management, Alaska Technical Report 50, 845 p.
|Reporters||J.M. Britton (Anchorage, Alaska); D.J. Grybeck (Contractor, U.S. Geological Survey)|
|Last report date||4/18/2010|