Moosehead Rack

Prospect, Probably inactive

Commodities and mineralogy

Main commodities Au
Ore minerals gold
Gangue minerals chalcopyrite; pyrite; pyrrhotite

Geographic location

Quadrangle map, 1:250,000-scale TN
Quadrangle map, 1:63,360-scale B-3
Latitude 65.25003
Longitude -151.27582
Nearby scientific data Find additional scientific data near this location
Location and accuracy Moosehead Rack, on the south bank of the Yukon River opposite the mouth of Morelock Creek, consists of a four-square-mile terrace rising abruptly more than 200 feet above the river to an elevation of about 900 feet. The site of this approximately located prospect is at an elevation of 600 feet at the west end of Moosehead Rack, in the northwest quarter of section 21, T. 5 N., R. 18 W., of the Fairbanks Meridian. The location is accurate to within a half-mile.

Geologic setting

Geologic description

The country rocks in the area of this prospect include a Cretaceous or Tertiary quartz monzonite stock, Paleozoic limestone, greenstone, and chert, and undated conglomerate, sandstone, shale, and lignite (Chapman and others, 1982). Moosehead Rack is a bedrock terrace cut by the Kaltag fault, a regional east-northeast-trending, right-lateral structure. Bedrock in the area is partly covered by Quaternary loess.
The prospect consists of pyritized hornfelsed slate and highly siliceous zones of breccia adjacent to megacrystic granite porphyry (WGM, Inc., 1998). Pyrite, pyrrhotite, and chalcopyrite locally constitute up to 6 percent of the host rock(s). Panning of some of the material yielded colors of gold. The prospect is marked by a red and yellow-white color anomaly, visible from the Yukon River.
Geologic map unit (-151.27832486954, 65.2495265141493)
Mineral deposit model Porphyry Cu-Au? (Cox and Singer, 1986; model 20c?).
Mineral deposit model number 20c?
Age of mineralization Cretaceous or younger, inferred from age of granitic pluton.
Alteration of deposit Oxidation of sulfide minerals.

Production and reserves

Workings or exploration The area has been explored by WGM, Inc. (1998). Details of their work have not been made public.
Indication of production None

Additional comments

Although this prospect is not on Doyon, Ltd., lands, mineral exploration of the ground is reported in documents held by Doyon, Ltd., Native Corporation. For more information, contact Doyon, Ltd., at 1 Doyon Place, Suite 300, Fairbanks, Alaska, 99701-2941.



Reporters G.E. Graham (ADGGS)
Last report date 11/28/2000