Big Boulder Creek

Occurrence in Alaska, United States with commodities Gold, Silver

Geologic information

Identification information

Deposit ID 10002200
MRDS ID A013100
Record type Site
Current site name Big Boulder Creek
Related records 10209526

Geographic coordinates

Geographic coordinates: -136.20213, 59.43974 (WGS84)
Relative position This occurrence is on Boulder Creek about 0.2 miles upstream from the Haines Highway. It is in the NE1/4, section 22, T. 28 S., R. 54 E. of the Copper River Meridian. It is shown as number 41 by Still and others (1984).
(click for info)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Gold Primary
Silver Secondary

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
    Stratigraphic age (youngest) Holocene
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Intermediate Volcanic Rock > Andesite

Nearby scientific data

(1) -136.20213, 59.43974

Comments on the geologic information

  • Geologic Description = Wright (1904 [B 225 and B 236]) cites the presence of placer gold in Boulder Creek stream gravels but doubts that there are sufficient quantities to warrant mining. Still and others (1984) noted that gold was found in stream gravels and boulders that included argillite float and that porphyritic andesite float was present at the mouth of the canyon just above the the alluvial fan near the Haines Highway.? Winkler and MacKevett (1970) collected several bedrock samples, MK 13A, MK 13D-1, and MK 13E, along Boulder Creek below the 1,000 foot elevation. Their description of MK 13A mentions an altered fault zone with quartz pods. The descriptions of MK 13D-1 and MK 13E mention quartz stringers. Sample MK 13A contained 1,500 ppm barium, 300 ppm lanthanum, 500 ppm niobium, 20 ppm tin, 200 ppm yttrium, and greater than 9,999 ppm zirconium. The description by MacKevett and others (1974) of an altered fault zone on Big Boulder Creek mentions fragmented pegmatitic material and apparently refers to the site sampled by MK 13A.? Bedded rocks within the Big Boulder Creek drainage area are variably metamorphosed, metasediments and metavolcanics of the Cheetdeekahyu Group of Redman and others (1985). North of the Klehini River, the metamorphic grade and average grain size of these rocks increases to the north and northeast towards Four Winds Mountain. These rocks have been included in the Four Winds metamorphic complex (Forbes and others, 1987; Gilbert and others, 1987). They are of probable Devonian or Late Triassic age (Gilbert and others, 1987).
  • Age = Quaternary placer.

Economic information

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Juneau (Skagway subdistrict)

Comments on the production information

  • Production Notes = Probably minor, at best.

Comments on the workings information

  • Workings / Exploration = Worked by hand methods in early 1900's, but no production is documented.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A013100
USGS Alaska Resource Data File ARDF SK038

Bibliographic references

  • Deposit

    Wright, C.W., 1904, The Porcupine placer mining district, Alaska in Emmons, S.F., and Hayes, C.W., eds., Contributions to economic geology 1903: U.S. Geological Survey Bulletin 225, p.60-63.

  • Deposit

    Wright, C.W., 1904, The Porcupine district, Alaska: U.S. Geological Survey Bulletin 236, 35 p.

  • Deposit

    Winkler, G.R., and MacKevett, E.M., Jr., 1970, Analyses of bedrock and stream-sediment samples from the Haines-Porcupine region, southeastern Alaska: U.S. Geological Survey Open-File Report 369, 91 p., 1 sheet, scale 1:125,000.

  • Deposit

    MacKevett, E.M., Jr., Robertson, E.C., and Winkler, G.R., 1974, Geology of the Skagway B-3 and B-4 quadrangles, southern Alaska: U.S. Geological Survey Professional Paper 832, 33 p.

  • Deposit

    Berg, H.C., 1984, Regional geologic summary, metallogenesis, and mineral resources of southeastern Alaska: U.S. Geological Survey Open-file Report 84-572, 298 p., 1 plate, scale approx. 1:600,000.

  • Deposit

    Still, J.C., Weir, K.R., Gilbert, W.G., and Redman, E.C., 1984, Stream-sediment, float, and bedrock sampling in the Porcupine mining area, southeast Alaska: U.S. Bureau of Mines Open-File Report 173-84, 19 p.

  • Deposit

    Redman, E.C., Gilbert, W.G., Jones, B.K., Rosenkrans, D.S., and Hickok, B.D., 1985, Preliminary bedrock-geologic map of the Skagway B-4 Quadrangle: Alaska Division of Geological and Geophysical Surveys Report of Investigations 85-6, 1 sheet, scale 1:40,000.

  • Deposit

    Gilbert, W.G., Burns, L.E., Redman, E.C., and Forbes, R.B., 1987, Preliminary bedrock geology and geochemistry of the Skagway B-3 Quadrangle, Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 87-2, 2 sheets, scale 1:36,200.

  • Deposit

    Forbes, R.B., Gilbert, W.G., and Redman, E.C., 1987, The Four Winds Complex; a newly recognized Paleozoic metamorphic terrane in southeastern Alaska [abs.]: Geological Society of America, Abstracts with Program, v. 19, no. 6, p. 378.

Comments on the references

  • Primary Reference = Still and others, 1984

General comments

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

Reporter information

Type Date Name Affiliation Comment
Reporter 04-FEB-2001 T.C. Crafford T. Crafford & Associates