East fork of Broxson Gulch Mine, Delta River Mining District, Southeast Fairbanks Census Area, Alaska, USAi

Regional Level Types
East fork of Broxson Gulch Mine	Mine
Delta River Mining District	Mining District
Southeast Fairbanks Census Area	Census Area
Alaska	State
USA	Country

Location: The locally named east fork of Broxson Gulch (see figure 2 of Rose, 1965) has been placer mined at several locations. For this record, the mine site is at an elevation of about 3,550 feet at a placer mine site reported by Rose. The mine is at the mouth of a steep-west flowing tributary to the east fork, about 1,000 feet east of the center of section 30, T. 18 S., R. 9 E., Fairbanks Meridian. The most recent place mining was about 3 miles south of the site described here, in the west bend of the east fork (W.T. Ellis, unpublished data, 1997).
Geology: The east fork of Broxson Gulch drains fault-juxtaposed bedded rocks of the Slana Spur Formation of Late Paleozoic age and complex thrust slices of Upper Triassic ultramafic intrusive complexes (Nokleberg and others, 1991; W.T. Ellis, unpublished data, 1996). At this placer mine site near the Broxson airstrip (built since the publication of the 1978 edition of the Mount Hayes B-5 topographic map) a tributary creek drains a small fault-bounded wedge of Tertiary conglomerate (W.T. Ellis, unpublished data, 1996). This conglomerate may be the material mapped as a Quaternary fan by Stout (1976). The upper course of this tributary crosses the Airport Fault that also juxtaposes Upper Triassic ultramafic rocks and volcaniclastic strata of the Slana Spur Formation (Rose, 1965, figure 2); Nokleberg and others, 1991). Little is known about the early placer mining here. Rose (1965, p. 35) deduced that the mine probably operated until about 1940 but that it had only small-scale activity after that. According to Rose (1965), gravel within a foot or two of the surface contained 4 to 7 colors of gold per pan; magnetite, pink garnet, and epidote occur in the concentrates. The headwaters of the tributary creek include lode mineral deposits (MH124, MH125, and MH136).
Workings: The placer workings are mainly at the mouth of the tributary to the east fork of Broxson Gulch, just north of the airstrip (built since the publication of the 1978 edition of the Mount Hayes B-5 topographic map). Equipment is scattered around the north end of the airstrip, and there is evidence that the gravel was bulldozed and run through a wash plant and sluice. Water was brought in by more than 2 miles of ditches. The main period of operation of the mine was probably about 1940 (Rose, 1965). The most recent mining occurred 3 miles to the south, at the west bend in the east fork of the stream in Broxson Gulch (W.T. Ellis, written communication, 1997). Production from this site was reported to be small, the gold very fine, and bedrock was not reached. The claims are now owned by MAN Resources.
Age: Holocene and Tertiary.
Production: There has been intermittent placer mining since the early 1900's. The amount of production is uncertain but probably small.

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

Other Databases

Link to USGS - Alaska:	MH123

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References