Swennings Greenpoint

Occurrence in Alaska, United States with commodities Silver, Molybdenum, Lead, Copper, Zinc
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 10000266
MRDS ID A010308
Record type Site
Current site name Swennings Greenpoint
Related records 10112513

Geographic coordinates

Geographic coordinates: -130.26565, 56.01477 (WGS84)
Relative position The Swennings Greenpoint mineral occurrence is in Section 33 above Greenpoint Glacier at an elevation of about 4200 feet (Berg and others, 1977, p. 92; Elliott and Koch, 1981, p. 13, loc. 36). This location is accurate to within about a quarter of a mile.

Site location context

Political divisions (FIPS codes)

Prince of Wales-Hyder(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Bradfield Canal A-1(quadrangle 1:63,360 scale)

Bradfield Canal SE(quadrangle 1:100,000 scale)

Bradfield Canal(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Southern Southeast Alaska(hydrologic accounting unit)

Southeast Alaska(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

Misty Fiords National Monument Wilderness(Wilderness)

Wilderness FS(Type of land area)

FS(Federal land areas administered by FS)

Tongass National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Misty Fjords National Monument Wilderness(Wilderness)

Wilderness FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Molybdenum Primary
Lead Primary
Copper Secondary
Zinc Critical Secondary

Materials information

Materials Type of material
Galena Ore
Molybdenite Ore
Quartz Gangue

Alteration

  • (Local) Local intense iron staining of quartz veins

Mineral occurrence model information

Model code 85
USGS model code 22c
Deposit model name Polymetallic veins
Mark3 model number 46

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Quartz Monzonite
  • Host or associated Host
    Rock type Metamorphic Rock > Hornfels
    Rock unit name Hazelton Group;Hyder
    Rock description Hazelton Group;Hyder

Nearby scientific data

(1) -130.26565, 56.01477

Economic information

Comments on the geologic information

  • Geologic Description = The country rocks in the area of this occurrence are pelitic metasedimentary strata of the Jurassic or older Mesozoic Hazelton Group, which are underlain and locally intruded by the Triassic Texas Creek Granodiorite; and the Eocene Hyder Quartz Monzonite, which intrudes the Hazelton and Texas Creek rocks (Smith, 1977; Berg and others, 1977, p. 15-17, 22-23; Koch, 1996).? the deposit consists of quartz veins in Hazelton hornfels about 50 feet from the contact of a dike of Hyder Quartz Monzonite (Berg and others, 1977, p. 92-93). The veins, which strike N30W and dip 65-70NE, are iron stained and contain scattered knots of galena and molybdenite. Assays of samples collected in 1972 by the U.S. Bureau of Mines showed as much as 100 ppm Ag, 350 ppm Cu, 4.5% Pb, 1000 ppm Zn, and 2000 ppm Mo.? Lead-isotope studies of galena from the Swennings Greenpoint occurrence (Maas and others, 1995, p. 229-248) indicate that the deposit is Eocene in age, contemporaneous with emplacement of the Hyder Quartz Monzonite.
  • Age = Lead-isotope studies of galena from the Swennings Greenpoint occurrence (Maas and others, 1995, p. 229-248) indicate that the deposit is Eocene in age, contemporaneous with emplacement of the Hyder Quartz Monzonite.

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Hyder

Comments on the workings information

  • Workings / Exploration = Assays of samples collected in 1972 by the U.S. Bureau of Mines (Berg and others, 1977) showed as much as 100 ppm Ag, 350 ppm Cu, 4.5% Pb, 1000 ppm Zn, and 2000 ppm Mo.

Reference information

Bibliographic references

  • Deposit

    Smith, J.G., 1977, Geology of the Ketchikan D-1 and Bradfield Canal A-1 quadrangles, Alaska: U.S. Geological Survey Bulletin 1425, 49 p.

  • Deposit

    Berg, H.C., Elliott, R.L., Smith, J.G., Pittman, T.L., and Kimball, A. L., 1977, Mineral resources of the Granite Fiords wilderness study area, Alaska, with a section on aeromagnetic data by Andrew Griscom: U.S. Geological Survey Bulletin 1403, 151 p.

  • Deposit

    Elliott, R.L., and Koch, R.D., 1981, Mines, prospects, and selected metalliferous mineral occurrences in the Bradfield Canal quadrangle, Alaska: U.S. Geological Survey Open-File Report 81-728-B, 23 p., 1 sheet, scales 1:250,000 and 1:63,360.

  • Deposit

    Maas, K.M., Bittenbender, P E., and Still, J.C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U.S. Bureau of Mines Open-File Report 11-95, 606 p.

  • Deposit

    Koch, R.D., 1996, Reconnaissance geologic map of the Bradfield Canal quadrangle, southeastern Alaska: U.S. Geological Survey Open-File Report 81-728-A, 35 p., 1 sheet, scale 1:250,000.

Comments on the references

  • Primary Reference = Berg and others, 1977

General comments

Subject category Comment text
Deposit Model Name = Polymetallic veins
Deposit Other Comments = Claims were inactive in 1973.?Site is in Misty Fiords National Monument.

Reporter information

Type Date Name Affiliation Comment
Reporter 17-MAY-1998 H. C. Berg 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.