Hoodoo and South Landlocked Bay Mining Co.

Past Producer in Alaska, United States with commodities Copper, Zinc, Silver, Gold
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Alteration
  8. Mineral occurrence model information
  9. Host and associated rocks
  10. Nearby scientific data
  11. Economic information about the deposit and operations
  12. Mining district
  13. Links to other databases
  14. Bibliographic references
  15. General comments
  16. Reporter information

Geologic information

Identification information

Deposit ID 10000368
MRDS ID A010435
Record type Site
Current site name Hoodoo and South Landlocked Bay Mining Co.
Related records 10112635

Geographic coordinates

Geographic coordinates: -146.55254, 60.84959 (WGS84)
Relative position This site represents a mine and a prospect along the south shore of Landlocked Bay. The map site is at an elevation of about 150 feet, just inland from the bay. It is in the NW1/4 sec. 7, T. 12 S., R. 7 W., of the Copper River Meridian. The site location is accurate to within 2000 ft. This site combines both sites C-70 and C-71 of Jansons and others (1984) and site #15 of Cobb (1972: MF-392).

Site location context

Political divisions (FIPS codes)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Cordova D-7 SW(quadrangle 1:24,000 scale)

Cordova NW(quadrangle 1:100,000 scale)

Cordova(quadrangle 1:250,000 scale)

Federal lands

Chugach National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Zinc Critical Primary
Silver Secondary
Gold Secondary

Comments on the commodity information

  • Ore Material = Copper (native)

Materials information

Materials Type of material
Chalcopyrite Ore
Sphalerite Ore
Copper Ore
Quartz Gangue

Alteration

  • (Local) Oxidation of copper minerals.

Mineral occurrence model information

Model code 90
USGS model code 24a
Deposit model name Massive sulfide, Cyprus
Mark3 model number 11

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Metavolcanic Rock
    Rock unit name Orca Group
    Rock description Orca Group
    Stratigraphic age (youngest) Pliocene
    Stratigraphic age (youngest) Pliocene

Nearby scientific data

(1) -146.55254, 60.84959

Economic information

Comments on the geologic information

  • Geologic Description = The mineral deposits at this site are in mafic volcanic rocks (greenstone) of the Tertiary Orca Group (Nelson and others, 1985) and consist of massive sulfide lenses in shear zones 1.5 ft. to 3 ft. wide (Jansons and others, 1984). The ore minerals are mainly chalcopyrite and sphalerite; native copper is also reported.? Development work began in 1904 (Cobb, 1979: OFR 79-973). Extensive surface stripping at 230 feet elevation exposed about 75 feet of a 3-foot-wide mineralized zone in metavolcanic rock striking N45W, and dipping 60 NE. Four tunnels were driven, the longest of which was 180 feet (Capps and Johnson, 1913). In 1953 one tunnel was inaccessible (Mihelich and Wells, 1957). Early assays contained 0.48 to 1.06 oz. Au/ton. Recent sampling (Jansons and others, 1984) of five chip samples from one adit contained 0.11 ppm to 2.9% Cu, 680 ppm to 0.95% Zn, <0.03 to 0.03 ppm Au, and 0.2 to 13.9 ppm Ag. Three grab samples contained 1.14% to 19.3% Cu, 0.95 to 2.25% Zn, 0.15 ppm to 44 ppm Au, and 0.23 ppm to 34 ppm Ag.
  • Age = Tertiary based on the age of the host rocks.

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Prince William Sound

Comments on the production information

  • Production Notes = None reported from Hoodo. The South Landlocked Bay mine produced 74, 240 lbs. Cu (Mihelich and Wells, 1957).

Comments on the reserve resource information

  • Reserves = Hoodo: inferred reserves of 300 tons @ 1.29% Cu, 0.34% Zn, and 7.97 ppm Ag. South Landlocked Bay: inferred reserves of 600 tons @ 4.7% Cu and 2.6% Zn (Jansons and others, 1984).

Comments on the workings information

  • Workings / Exploration = Development work began in 1904 (Cobb, 1979: OFR 79-973) Extensive surface stripping at 230 feet elevation exposed about 75 feet of a 3-foot-wide mineralized zone in metavolcanic rock striking N45W, and dipping 60 NE. Four tunnels were driven, the longest of which was 180 feet (Capps and Johnson, 1913). In 1953 one tunnel was inaccessible (Mihelich and Wells, 1957). Early assays contained 0.48 to 1.06 oz. Au/ton. Recent sampling (Jansons and others, 1984) of five chip samples from one adit contained 0.11 ppm to 2.9% Cu, 680 ppm to 0.95% Zn, <0.03 to 0.03 ppm Au, and 0.2 to 13.9 ppm Ag. Three grab samples contained 1.14% to 19.3% Cu, 0.95 to 2.25% Zn, 0.15 ppm to 44 ppm Au, and 0.23 ppm to 34 ppm Ag.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Jansons and others, 1984

General comments

Subject category Comment text
Deposit Model Name = Cyprus massive sulfide (Cox and SInger, 1986; model 24a)
Deposit Other Comments = Crowe and others (1992; 1993) and Sainsbury (1993) discuss the genesis of the volcanogenic massive sulfide deposits in this area.? Chugach Alaska Corporation, Anchorage, Alaska has control of these lands.

Reporter information

Type Date Name Affiliation Comment
Reporter 10-JUN-00 S.W. Nelson U.S. Geological Survey

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Authoritative Alaska resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.