Unnamed (at head of Siksikpuk River)

Occurrence, Probably inactive

Commodities and mineralogy

Main commodities Pb; Zn
Other commodities Ba
Ore minerals galena; marcasite; pyrite; sphalerite
Gangue minerals calcite; quartz; siderite

Geographic location

Quadrangle map, 1:250,000-scale CL
Quadrangle map, 1:63,360-scale B-4
Latitude 68.271
Longitude -152.3296
Nearby scientific data Find additional scientific data near this location
Location and accuracy The location of this occurrence is somewhat ambiguous in Kurtak and others (1995) but it is probably about 8.5 miles northwest of Inualurak Mountain in the southeast part of section 34, T. 13 S., R. 2 W. The location is probably accurate to within a half mile.

Geologic setting

Geologic description

This occurrence is in a 42.9-meter-thick fissile, carbonaceous black shale member of the Kayak Shale between a lower argillaceous member and an upper red limestone member. The black shale member contains red-brown, cherty ironstone nodules or concretions that vary from rounded forms about 4 centimeters in diameter to elongate forms about 8 by 38 centimeters in size. The concretions consist of quartz, calcite, siderite, pyrite (or marcasite?), minor sphalerite, and rare galena (Kurtak and others, 1995). There are also 2.5- to 5-centimeter sulfide-bearing beds in the black shale. Several samples of the concretions from a 6-meter-thick section of the black shale contained up to 13,152 parts per million (ppm) zinc, more than 2,000 ppm barium, and 52 ppm lead. Samples from a 10-centimeter-thick, cherty ironstone bed at the base of the black shale member contained up to 1,357 ppm zinc.
Although this record describes a specific site, Kurtak and others (1995) note that it is representative of similar sulfide occurrences in a member of the Early Mississippian Kayak Shale that outcrops for several hundred kilometers along the north side of the Brooks Range.
Geologic map unit (-152.332422852753, 68.2705662659229)
Mineral deposit model Stratiform zinc(-lead) deposit?
Age of mineralization Syngenetic deposit in Early Mississippian black shale.

Production and reserves

Workings or exploration Only sampling by government agencies.
Indication of production None

Additional comments

MAS No. 0020220017.

References