Grub Gulch

Past Producer in Alaska, United States with commodity Gold

Geologic information

Identification information

Deposit ID 10002038
MRDS ID A012886
Record type Site
Current site name Grub Gulch
Related records 10136377

Geographic coordinates

Geographic coordinates: -165.38968, 64.71873 (WGS84)
Relative position This placer gold mine is on Grub Gulch, an east tributary to lower Goldbottom Creek. The mouth of Grub Gulch is about 1.5 miles upstream of the confluence of Goldbottom Creek and North Fork Snake River. About 1,400 feet of Grub Gluch has been placer mined upstream of the Snake River road crossing. The map location is at the approximate midpoint of the workings, in the SW1/4 section 12, T. 9 S., R. 33 W., Kateel River Meridian. This is locality 88 of Cobb (1972 [MF-463], 1978 [OFR 78-93]).
(click for info)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Gold Primary

Materials information

Materials Type of material
Gold Ore
Quartz Gangue

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) -165.38968, 64.71873

Comments on the geologic information

  • Geologic Description = The lower half-mile or so of Grub Gulch, at surface elevations less than 300 feet, was placer mined by hand or horse-drawn scrapers and apparently worked out before 1905 (Collier and others, 1908; Moffit, 1913). The pay streak was 40 feet wide and 5 to 6 feet thick in gravels containing schist, vein quartz, and some granite boulders. Recovered gold was coarse, rough, and reported to run 3.75 dollars (about 0.18 ounce) per cubic yard (Moffit, 1913). Grub Gulch crosses graphitic quartz schists, calcareous mica schist, and a 150-foot-thick, east-dipping, highly competent granitic orthogneiss (C.C. Hawley, written communication for Kennecott Exploration Company, 1995). The placer mainly overlies mica schist bedrock that probably has an early Paleozoic protolith age (Hummel, 1962 [MF 247]; Sainsbury, Hummel, and Hudson, 1972 [OFR 72-326]; Till and Dumoulin, 1994; Bundtzen and others, 1994). The granitic boulders in Grub Gulch probably are derived from the orthogneiss upstream. In other nearby creeks that partly traverse orthogneiss (for example, Seattle Creek, NM200), quartz boulders are abundant along and immediately downstream from, orthogneiss bedrock sections of the creek, suggesting that some of the gold may have been derived from quartz veins at the contacts of the orthogneiss.
  • Age = Quaternary.

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 Nome

Comments on the workings information

  • Workings / Exploration = This placer deposit was worked by hand or horse-drawn scrapers mainly between 1903 and 1906. The pay averaged about 0.18 ounce of gold per cubic yard.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A012886
USGS Alaska Resource Data File ARDF NM199

Bibliographic references

  • Deposit

    Collier, A. J., Hess, F.L., Smith, P.S., and Brooks, A.H., 1908, The gold placers of parts of Seward Peninsula, Alaska, including the Nome, Council, Kougarok, Port Clarence, and Goodhope precincts: U.S. Geological Survey Bulletin 328, 343 p.

  • Deposit

    Moffit, F.H., 1913, Geology of the Nome and Grand Central quadrangles, Alaska: U.S. Geological Survey Bulletin 533, 140 p.

  • Deposit

    Hummel, C.L., 1962, Preliminary geologic map of the Nome C-1 quadrangle, Seward Peninsula, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-247, 1 sheet, scale 1:63,360.

  • Deposit

    Sainsbury, C.L., Hummel, C.L., and Hudson, Travis, 1972, Reconnaissance geologic map of the Nome quadrangle, Seward Peninsula, Alaska: U.S. Geological Survey Open-File Report 72-326, 28 p., 1 sheet, scale 1:250,000.

  • Deposit

    Cobb, E.H., 1972, Metallic mineral resources map of the Nome quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-463, 2 sheets, scale 1:250,000.

  • Deposit

    Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Nome quadrangle, Alaska: U.S. Geological Survey Open-File report 78-93, 213 p.

  • Deposit

    Till, A.B., and Dumoulin, J.A, 1994, Geology of Seward Peninsula and St. Lawrence Island, in Plafker, G., and Berg, H.C., eds., The Geology of Alaska: Geological Society of America, The Geology of North America, DNAG, v. G-1, p. 141-152.

  • Deposit

    Bundtzen, T.K., Reger, R.D., Laird, G.M., Pinney, D.S., Clautice, K.H., Liss, S.A., and Cruse, G.R., 1994, Progress report on the geology and mineral resources of the Nome mining district: Alaska Division of Geological and Geophysical Surveys, Public Data-File 94-39, 21 p., 2 sheets, scale 1:63,360.

Comments on the references

  • Primary Reference = This report

General comments

Subject category Comment text
Deposit Model Name = Alluvial placer Au (Cox and Singer, 1986; model 39a).

Reporter information

Type Date Name Affiliation Comment
Reporter 10-JUL-00 Hawley, C.C. Hawley Resource Group
Reporter 10-JUL-00 Travis L. Hudson Hawley Resource Group