Mogul

Prospect, Inactive

Commodities and mineralogy

Main commodities Au
Ore minerals gold; sulfides
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale AN
Quadrangle map, 1:63,360-scale D-6
Latitude 61.83
Longitude -149.17
Nearby scientific data Find additional scientific data near this location
Location and accuracy In upper Reed Creek valley, about 1 mile north-northeast from the end of the unimproved road that is parallel to Reed Creek. Accurate within 2,000 ft. Locality 32 of Cobb (1972) and locality 22 of MacKevett and Holloway (1977).

Geologic setting

Geologic description

Gouge zone containing quartz veins in early Paleocene and Late Cretaceous quartz diorite. The vein quartz is drusy and contains scattered unspecified sulfides and much iron oxide. The quartz vein is 1 is 4 inches thick in all three open cuts. In one cut the vein is separated from another 12 inch quartz vein by 18 inches of altered quartz diorite. The vein was reported to have given high assays in gold (Capps, 1915).
The early Paleocene and Late Cretaceous quartz diorite is part of a pluton which is mostly biotite-hornblende tonalite with lesser biotite-hornblende quartz diorite. Wall-rock alteration within a few inches of the veins is intense, but seldom extends more than 10 to 12 inches beyond the quartz filling. Sericitization and carbonate alteration predominate, but there is some pyritization and in the outer parts of the alteration zone chloritization is present (Ray, 1954).
Geologic map unit (-149.172205966224, 61.829472435496)
Mineral deposit model Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)
Mineral deposit model number 36a
Age of mineralization Late Cretaceous or younger; veins cut early Paleocene and Late Cretaceous quartz diorite.
Alteration of deposit Wall-rock alteration within a few inches of the veins is intense, but seldom extends more than 10 to 12 inches beyond the quartz filling. Sericitization and carbonate alteration predominate, but there is some pyritization and in the outer parts of the alteration zone chloritization is present (Ray, 1954). Oxidation of sulfide minerals.

Production and reserves

Workings or exploration Development consists of three open cuts made across vein which reportedly had high assays in gold (Capps, 1915).
Indication of production None

References

MRDS Number A011634
Reporters D.P. Bickerstaff (USGS contractor); S.W. Huss (USGS)
Last report date 7/30/1998