Super Cub Ridge (ARDF #MH331) Fe

Super Cub Ridge

Occurrence, Active

Commodities and mineralogy

Main commodities	Fe
Other commodities	Zn
Ore minerals	magnetite; sphalerite
Gangue minerals	chlorite; quartz; sericite

Geographic location

Quadrangle map, 1:250,000-scale	MH
Quadrangle map, 1:63,360-scale	B-1
Latitude	63.2752
Longitude	-144.0747
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	The Super Cub Ridge occurrence is about 2.5 miles southeast of the confluence of the Robertson River and Rumble Creek at an elevation of about 5,500 feet. It is about one-half mile north-northeast of the center of section 9, T. 17 N., R. 7 E., Copper River Meridian. The location is accurate.

Geologic setting

Geologic description Pods of pyrrhotite-magnetite skarn occur in the Tushtena Pass unit at the contact with a gabbroic sill (S.S. Dashevsky, written communication, 2002). The Tushtena Pass unit consists mainly of medium- to coarse-grained calcareous quartz-sericite-chlorite schist with carbonate interbeds. The schist is typically green to gray and laminated to layered and contains quartz eyes. Discontinuous bands of siliceous limestone, dolomitic marble, and black pyritic metasiltstone are common. A poorly exposed graphitic member in its upper part is a stratigraphic marker that can be traced by electromagnetic surveys. Quartz-carbonate veins and bands are characteristic of the Tushtena Pass unit. It is intruded and thickened by gabbroic sills and dikes, many of which are associated with local hornfelsing in nearby rocks.
Geologic map unit	(-144.076951936642, 63.2748256413581)
Mineral deposit model	Iron skarn (Cox and Singer, 1986; model 18d).
Mineral deposit model number	18d
Age of mineralization	Mid-Triassic, on the basis of the U-Pb zircon age of gabbroic bodies that are related to this deposit (Dashevsky and others, 2003).

Production and reserves

Indication of production	None
Additional comments Unpublished data cited is available for viewing by contacting Grayd Resources Inc. in Vancouver, B. C., Canada (www.grayd.com), or Northern Associates Inc. in Fairbanks, Alaska.

References

References Dashevsky, S.S., Schaefer, C.F., and Hunter, E.N., 2003, Bedrock geologic map of the Delta mineral belt, Tok mining district, Alaska: Alaska Division of Geological and Geophysical Surveys Professional Report 122, 2 sheets, scale 1:63,360.
Reporters	W.T. Ellis (Alaska Earth Sciences) and A.W. Wyatt and S.S. Dashevsky (Northern Associates Inc.)
Last report date	3/20/2003