|Quadrangle map, 1:250,000-scale||KL|
|Quadrangle map, 1:63,360-scale||A-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is 5.9 miles at an azimuth of 305 degrees from the small lake at the divide between a tributary to Kakivilak Creek and head of Itilyiargiok Creek. It is about 0.5 mile west of the center of section 32, T. 32 N., R. 16 E. The location is accurate to within about a half mile.|
This occurrence is near the contact of shale and sandstone of the Upper Devonian, Hunt Fort Shale and the Upper Devonian or Lower Mississippian, Kanayut Conglomerate. As originally identified by the U.S. Geological Survey (Kelly and Mull, 1995), the occurrence is a single 5-meter-wide outcrop exposed along strike for about 25 meters. The mineralization is in shale and sandstone and consists of galena, sphalerite, chalcopyrite, and pyrite in quartz veins and in quartz-cemented breccia. The veins trend N40E with a shallow northwest dip. There is noticeable banding in the sulfides. Samples collected by the U.S. Geological Survey contained up to 25 percent zinc, 1 percent copper, 1.5 to 2 percent lead, 300 parts per million (ppm) silver, 1,000 ppm arsenic, and 0.75 ppm gold. Three continuous chip samples averaging 2.6 meters in length were collected by the U.S. Bureau of Mines (Kurtak and others, 1995). They averaged 2.0 percent zinc, 1.1 percent lead, 1,103 ppm copper, and 130 grams of silver per tonne. A select sample from an outcrop contained 56.9 percent zinc, 9.8 percent lead, 1,287 grams of silver per tonne, and 1,056 ppm copper.Kurtak and others (1995) found similar mineralization nearby, about 0.8 mile north of the discovery outcrop. There, galena and sphalerite are in quartz veinlets and veins 6 millimeters to 15 centimeters thick that cut sandstone. Two select samples contained up to 1.4 percent lead, 12.1 percent zinc, and 432.4 ppm silver. About 0.6 mile northwest of the discovery outcrop, a grab sample of vein quartz in float contained 3.5 percent lead and 32 ppm silver.
|Geologic map unit||(-155.286566797376, 68.1292126742782)|
|Mineral deposit model||Silver-lead-zinc-quartz veins and quartz breccia.|
|Age of mineralization||Late Devonian or younger based on the age of the host rock. Possibly Late Jurassic to Cretaceous based on analogy with other deposits in the western Brooks Range.|
|Alteration of deposit||Not mentioned.|
|Workings or exploration||Only limited sampling and mapping by the U.S. Geological Survey and U.S. Bureau of Mines.|
|Indication of production||None|
Additional commentsMAS No. 0020210004
Duttweiler K.A., 1987, Use of factor analysis in locating base metal mineralization in the Killik River Quadrangle, Alaska: U.S. Geological Survey Circular C 0998, p. 27-30.
Kelley, K.D., and Kelley, D.L., 1992, Reconnaissance exploration geochemistry in the central Brooks Range, northern Alaska; implications for exploration of sediment-hosted zinc-lead-silver deposits: Journal of Geochemical Exploration, vol .42, no.2-3, p..273-300.
Kelley, K.D., and Mull, C.G., 1995, Maps showing areas of potential for mineral resources in the Killik River 1 degree x 3 degree quadrangle, Brooks Range, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-2225-A, 1 sheet, scale 1:250,000.
Kelley, K.D., Mull, C. G., and Barton, H. N., 1995, Maps showing the distribution of selected elements in minus-30-mesh stream-sediment samples from the southern part of the Killik River 1 degree x 3 degree quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-2225-C, 2 sheets, scale 1:250,000.
|Reporters||J.M. Schmidt (U.S. Geological Survey); K.D. Kelley (U.S. Geological Survey); D.J. Grybeck (Contractor, U.S. Geological Survey)|
|Last report date||4/18/2010|