Greenhorn Gulch

Past Producer in Alaska, United States with commodities Gold, Silver

Geologic information

Identification information

Deposit ID 10001486
MRDS ID A012232
Record type Site
Current site name Greenhorn Gulch
Related records 10112320

Geographic coordinates

Geographic coordinates: -145.07404, 65.45084 (WGS84)
Relative position Greenhorn Gulch extends about 1.5 mi north and 1.5 mi south of the coordinate intersection; it is a tributary of Boulder Creek. Mining activity in the 1970's and 1980's also has occurred at the junction with Tinhorn Gulch.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Gold Primary
Silver Secondary

Materials information

Materials Type of material
Gold Ore

Mineral occurrence model information

Model code 119
USGS model code 39a
BC deposit profile C01. C02
Deposit model name Placer Au-PGE
Mark3 model number 54

Host and associated rocks

  • Host or associated Host
    Rock type Unconsolidated Deposit > Gravel

Nearby scientific data

(1) -145.07404, 65.45084

Comments on the geologic information

  • Geologic Description = The creek along Greenhorn Gulch flows north for approximately 5 km before joining Boulder Creek. Bedrock throughout the entire Greenhorn Gulch drainage is the Lower Schist unit described by Wiltse and others (1995) as slightly calcareous quartz-muscovite schist, porphyroblastic albite-quartz-chlorite-muscovite schist, and lesser amounts of quartzose porphyroblastic albite-chlorite schist and chlorite schist.? An alluvium-covered bench on the west side of the gulch is 8 to 12 m above the valley bottom and grades into the bench in Boulder Creek. The creek gravel in Greenhorn Gulch is composed of boulders up to 70 cm in diameter, but are more commonly 10 to 30 cm across. The gravel is 1 to 2 meters thick over the schist bedrock and is as much as 30 meters wide (Yeend, 1991). A fragment of vein quartz with cavities from which sulfides had been weathered out assayed 24 oz. silver per ton and contained specks of free gold (Spurr, 1898, p. 293).

Economic information

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Circle

Comments on the production information

  • Production Notes = A 2.5 oz gold nugget was recovered in the early days of mining, and vein quartz in the gravel reportedly contained finely disseminated free gold (Spurr, 1898).

Comments on the workings information

  • Workings / Exploration = There was small-scale placer mining reported in 1896, and 1911 to 1912; however, mining was hampered by the lack of water. Recent mining activity in the 1970's and 1980's has occurred on the creek junction with Tinhorn Gulch (Yeend, 1991; Menzie and others, 1983).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A012232
USGS Alaska Resource Data File ARDF CI023

Bibliographic references

  • Deposit

    Spurr, J.E., 1898, Geology of the Yukon gold district, Alaska, with an introductory chapter on the history and conditions of the district to 1897 by H.B. Goodrich: U.S. Geological Survey 18th Annual Report, Part 3, p. 87-392.

  • Deposit

    Brooks, A.H., 1907, The Alaskan mining industry in 1906: U.S. Geological Survey Bulletin 314, p. 19-39.

  • Deposit

    Ellsworth, C.E., 1912, Placer mining in the Fairbanks and Circle Disctricts: U.S. Geological Survey Bulletin 520, p. 240-245.

  • Deposit

    Ellsworth, C.E., and Davenport, R.W., 1913, Placer mining in the Yukon-Tanana region: U.S. Geological Survey Bulletin 542, 303 p.

  • Deposit

    Mertie, J.B., Jr., 1932, Mining in the Circle district: U.S. Geological Survey Bulletin 824, p. 155-172.

  • Deposit

    Mertie, J.B., Jr., 1938, Gold placers of the Fortymile, Eagle, and Circle districts, Alaska: U.S. Geological Survey Bulletin 897-C, p. 133-261.

  • Deposit

    Cobb, E.H., 1972, Metallic mineral resources map of the Circle quadrangle, Alaska: U.S. Geological Survey Misc. Field Studies Map MF-391, 1 sheet, scale 1:250,000.

  • Deposit

    Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Circle quadrangle, Alaska: U.S. Geological Survey Open-File Report 76-633, 72 p.

  • Deposit

    Eakins, G.R., Jones, B.K. and Forbes, R.B., 1977, Investigation of Alaska's uranium potential: Alaska Division of Geological and Geophysical Surveys Open-File Report 109, 213 p., 10 sheets, scale 1:40,000.

  • Deposit

    Barker, J.C., 1979, Trace element study of the Circle mining district, Alaska: U.S. Bureau of Mines Open-File Report 57-79, 74 p.

  • Deposit

    Menzie, W.D., Foster, H.L., Tripp, R.B., and Yeend, W.E., 1983, Mineral resource assessment of the Circle quadrangle, Alaska: U.S. Geological Survey Open-File Report 83-170-B, 61 p., 1 sheet, 1:250,000.

  • Deposit

    Yeend, W.E., 1991, Gold placers of the Circle district, Alaska - past, present, and future: U.S. Geological Survey Bulletin 1943, 42 p.

  • Deposit

    Wiltse, M.A., Reger, R.D., Newberry, R.J, Pessel, G.H., Pinney, D.S., Robinson, M.S., and Solie, D.N., 1995, Bedrock geologic map of the Circle mining district, Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 95-02b, 1 sheet, scale 1:63,360.

  • Deposit

    Prindle, L.M., 1913, A geologic reconnaissance of the Circle quadrangle, Alaska: U.S. Geological Survey Bulletin 538, 82 p.

General comments

Subject category Comment text
Deposit Model Name = Placer gold deposit (Cox and Singer, 1986; model 39a)
Deposit Other Comments = Greenhorn Gulch is the only part of the Boulder Creek drainage that has had significant placer mining activity. Greenhorn Gulch has also been called Greenhorn Creek but it should not be confused with the much less productive 'Greenhorn Creek' that is a tributary of Bottom Dollar Creek.

Reporter information

Type Date Name Affiliation Comment
Reporter 09-SEP-98 C.J. Freeman Avalon Development Corporation
Reporter 09-SEP-98 J.R. Guidetti Schaefer Avalon Development Corporation
Reporter 09-SEP-98 Clements, A.S. Avalon Development Corporation