Unnamed (headwaters of North Fork, Mosquito Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Pb; Zn
Other commodities Sb; Sn

Geographic location

Quadrangle map, 1:250,000-scale BN
Quadrangle map, 1:63,360-scale A-2
Latitude 65.09
Longitude -162.6
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is on the ridge crest (approximate 1,850 feet elevation) on the north side of the headwaters of North Fork, Mosquito Creek. Mosquito Creek flows westward from headwaters in the northern Darby Mountains to Telephone Creek, a tributary to Fish River in McCarthy's Marsh. It is approximately the location of sample localities 5 and 6 of Miller and Grybeck (1973). Gamble (1988) showed these as locations 50 and 51.

Geologic setting

Geologic description

Two samples of apparently small, iron-stained zones in metamorphosed carbonate rocks were collected by Miller and Grybeck (1973) near this location. A composite grab sample of iron-stained carbonate contained 70 ppm Ag, 2,000 ppm As, 0.1 ppm Au, 200 ppm Cu, greater than 20,000 ppm Pb, 700 ppm Sb, 500 ppm Sn, and 7,000 ppm Zn. A grab sample of gossan in calcareous metasedimentary rock contained 3 ppm Ag, 3,000 ppm As, 200 ppm Cu, 70 ppm Mo, 1,500 ppm Pb, and greater than 10,000 ppm Zn. These occurrences are in lower Paleozoic metasedimentary rocks (Till and others, 1986).
Geologic map unit (-162.602619567073, 65.0892950662664)
Mineral deposit model Sulfide veins and/or replacements in carbonate rocks
Age of mineralization Cretaceous ?; Epigenetic mineralization in metamorphic rocks of Seward Peninsula is primarily of Cretaceous age.
Alteration of deposit These occurrences are oxidized, gossanous zones in metacarbonate rocks.

Production and reserves

Workings or exploration None are known, some shallow hand dug prospecting pits may be locally present in this area.
Indication of production None

References