Upper McCumber Creek Prospect, Delta River Mining District, Southeast Fairbanks Census Area, Alaska, USAi

Regional Level Types
Upper McCumber Creek Prospect	Prospect
Delta River Mining District	Mining District
Southeast Fairbanks Census Area	Census Area
Alaska	State
USA	Country

Location: This placer prospect is at an elevation of 2,700 on upper McCumber Creek in the NW1/4NE1/4 section 15, T. 14 S, R. 11 E., Fairbanks Meridian. It corresponds to locality 3 of Cobb (1979 [OFR 79-238]) and locality N2 in table 3 of Nokelberg and others (1991). The location is accurate within a mile.
Geology: In the McCumber Creek area small amounts of gold occur in alluvial gravel in streams draining an area of extensive glacial deposits (Smith, 1932). The gravel consists mainly of metasedimentary schists (Nokleberg and others, 1991). The most common bedrock types in the area are quartz-mica schist and quartz-rich phyllite; sulfide-bearing cobbles and quartz float are common (T. Hinderman, written communication, 1986). The schist is cut by diabase dikes and is overlain by conglomerate of the Nenana Gravel of Tertiary age, which is considered to be the source of placer gold in other districts in central Alaska (T. Hinderman, written communication, 1986). Gold recovered by T. Hinderman from Morningstar Creek in 1986 was flat and contained minor inclusions of silver. Most of the minerals accompanying the gold were garnet and magnetite.
Workings: Mining claims on McCumber Creek recorded in 1954 reportedly were idle in 1974 (Mulligan, 1974). In 1986 the McCumber Morningstar Property consisted of 40 State claims controlled by Richard Knudsen of Anchorage (T. Hinderman, written communication, 1986). A placer test completed in 1986 resulted in the owner allowing the claims to lapse. The test showed a resource in lower Morningstar Creek of 128,000 cubic yards of gravel grading $4.83 (0.019 ounce of gold) per cubic yard. McCumber Creek contains a much larger, lower-grade resource of 1,200,000 cubic yards of gravel grading $1.18 (0.0045 ounce of gold) per cubic yard.
Age: Holocene.

Commodities (Major) - Au
Development Status: Yes; small
Deposit Model: Placer Au (Cox and Singer, 1986; model 39a).

Other Databases

Link to USGS - Alaska:	MH017

Other Regions, Features and Areas containing this locality

References