Unnamed Occurrences (ARDF - SP009; Tupik Creek area), Noatak Mining District, Northwest Arctic Borough, Alaska, USAi

Regional Level Types
Unnamed Occurrences (ARDF - SP009; Tupik Creek area)	- not defined -
Noatak Mining District	Mining District
Northwest Arctic Borough	Borough
Alaska	State
USA	Country

Located within Gates of the Arctic National Park.
Location: This site is a composite of four occurrences (localities 18-22 of Grybeck and Nelson, 1981) in an area of about 6 square miles on both sides of Tupik Creek. The coordinates are for the center of the area in the NW1/4 of sec. 3, T. 24 N., R. 17 E., of the Kateel River Meridian. Location of area accurate to within 2000 ft.
Geology: This composite site represents a number of occurrences that share a common geologic enviroment marked by flat-lying Paleozoic gneiss and schist and Devonian and Silurian limestone and shale that overlie a large Devonian gneissic granite pluton. Small erratic skarn bodies are common where carbonates are present. Five mineral occurrences within the area are specifically noted by Grybeck and Nelson (1981), and others probably could be found with some search. Most are small and erratic; they rarely are more than a few feet or tens of feet in area and they are usually hundreds of feet or more apart. Impressive hand samples containing ore minerals were collected within the area, but no widespread concentration of ore minerals was noted. The mineralogy of the occurrences is highly variable. It includes various combinations of galena, sphalerite, stibnite, chalcopyrite, magetite, and molybdenite, often associated with quartz and fluorite, and, in the skarns, various calc-silicate minerals. Highly select grab samples of the more sulfide-rich rocks contain up to 55 ppm Ag, 55 ppm Au, 70 ppm Be, 700 ppm Bi, 1000 ppm Sn, and, in the skarns, 300 ppm W. The overall environment is that of contact metamorphism marked by very spotty metamsomatic mineralization. The source of the metals is the large Devonian granite pluton that underlies most of the area. Similar mineralization is recognized elsewhere in the Brooks Range and is described by Newberry and others (1986).
Workings: Samples were mostly collected during spot stops and short traverses during geologic mapping by the USGS in the late 1970s.
Age: Deposits formed by metasomatic introduction of metals related to intusion of Devonian granite.
Alteration: Metasomatic alteration related to contact metamorphism: calc-silicate minerals, sulfides and quartz.

Commodities (Major) - Cu, Pb, Sn; (Minor) - Ag, Au, Be, Bi, F, Mo, Sb, W, Zn
Development Status: None
Deposit Model: Skarn (Cox and Singer, 1986; model 14b)

Other Databases

Link to USGS - Alaska:	SP009

Other Regions, Features and Areas containing this locality

References