Unnamed (near upper Niukluk River) (ARDF #BN130) Ag, Cu, Pb, Zn

Unnamed (near upper Niukluk River)

Prospect, Inactive

Commodities and mineralogy

Main commodities	Ag; Cu; Pb; Zn
Ore minerals	azurite; cerrusite; chalcopyrite; chrysocolla; galena; malachite
Gangue minerals	limonite; pyrite; quartz

Geographic location

Quadrangle map, 1:250,000-scale	BN
Quadrangle map, 1:63,360-scale	A-4
Latitude	65.199
Longitude	-163.866
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This prospect is on a ridge crest along the south side of an unnamed east headwater tributary of Niukluk River. It is about 2,000 feet south of the creek at an elevation of approximately 2,000 feet. It is 4,500 feet northwest of the skarn propect at BN110. This is locality 83 of Gamble (1988).

Geologic setting

Geologic description Highly oxidized, locally brecciated pyrite-chalcopyrite-galena-bearing drusy comb-quartz veins in high grade metamorphic rocks are present here. Secondary minerals include limonite, azurite, cerussite, chrysocolla, and malachite. Grab samples contain up to greater than 2 % Pb, greater than 2% Cu, 8,200 ppm Zn, 300 ppm Ag, 460 ppm Sb, 1,000 ppm As, 190 ppm Cd, 70 ppm Sn, and 14 ppm Bi (Gamble, 1988). The mineralized rocks occur as float and on dumps of shallow prospect pits or short adits. This locality, and several others in this part of the Bendeleben A-4 quadrangle, are in high grade metamorphic rocks that are structurally above or peripheral to the crosscutting Pargon pluton. The Pargon pluton is mostly granodiorite and assumed to be Cretaceous in age (Till and others, 1986). It was emplaced at shallower depths than the more deep-seated Bendeleben pluton to the east. The metamorphic rocks peripheral to the western Pargon pluton are also intruded by small, felsic dikes and plugs including quartz porphyry and muscovite granite.
Geologic map unit	(-163.868643174096, 65.1982753936467)
Mineral deposit model	Polymetallic vein in high-grade metamorphic rocks (Cox and Singer, 1986; model 22c?).
Mineral deposit model number	22c?
Age of mineralization	Cretaceous; this occurrence is probably related to emplacement of the Pargon pluton which is assumed to be Cretaceous in age.
Alteration of deposit	Abundant secondary minerals are developed from the oxidation of sulfides.

Production and reserves

Workings or exploration	Some shallow prospecting pits or short adit(s) are present here.
Indication of production	None

References

MRDS Number	10307295
References Gamble, B.M., 1988, Non-placer mineral occurrences in the Solomon, Bendeleben, and southern part of the Kotzebue quadrangles, western Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1838-B, 13 p., 1 sheet, scale 1:250,000. Sainsbury, C.L., Curry, A.I., and Hamilton, J.C., 1973, An integrated system of geologic mapping and geochemical sampling by light aircraft: U.S. Geological Survey Bulletin 1361, 28 p. Till, A.B., Dumoulin, J.A., Gamble, B. ., Kaufman, D.S., and Carroll, P.I., 1986, Preliminary geologic map and fossil data, Soloman, Bendeleben, and southern Kotzebue quadrangles, Seward Peninsula, Alaska: U.S. Geological Survey Open-File Report 86-276, 10 p., 3 plates, scale 1:250,000.
Reporters	Travis L. Hudson (Applied Geology)
Last report date	3/15/1999