1. Mineral Resources
  2. Online Spatial Data
  3. Mineral Resource Data System (MRDS)

Unnamed (near Spine Mountain)

Occurrence in Alaska, United States with commodities Silver, Copper
Map
XML
JSON
KML
C
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 10307683
Record type Site
Current site name Unnamed (near Spine Mountain)

Geographic coordinates

Geographic coordinates: -131.47976, 55.20774 (WGS84)
Relative position This occurrence is at an elevation of 900 feet, about 1.2 miles north-northwest of the top of Spine Mountain, and about a mile east of Helen Todd Lake. The site is in section 12, T. 77 S., R. 92 E., of the Copper River Meridian. It corresponds to loc. 13 in Karl (1992). The location is accurate within 0.1 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

Ketchikan A-5(quadrangle 1:63,360 scale)

Ketchikan SW(quadrangle 1:100,000 scale)

Ketchikan(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Ketchikan(hydrologic unit)

Southern Southeast Alaska(hydrologic accounting unit)

Southeast Alaska(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

Annette Island Indian Reservation(American Indian Reservation)

American Indian Reservation BIA(Type of land area)

BIA(Federal land areas administered by BIA)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Copper Primary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore

Alteration

  • (Local) Country rocks are pyritized.

Mineral occurrence model information

Model code 273
USGS model code 36a
Deposit model name Low-sulfide Au-quartz vein
Mark3 model number 27

Host and associated rocks

  • Host or associated Host
    Rock type
    Stratigraphic age (youngest) Cretaceous
    Stratigraphic age (oldest) Late Jurassic

Nearby scientific data

(1) DOgi
ListMap

Economic information

Comments on the geologic information

  • Geologic Description = The country rocks in the area of this site are Upper Jurassic or Cretaceous flyschlike metasedimentary rocks that are gradationally interbedded with subordinate andesitic or basaltic metatuff (Berg, 1972 [I 684]; Berg and others, 1988; Karl, 1992). The area also contains small, generally fault-bounded, outcrop areas of recrystallized Upper Triassic basalt and limestone. The rocks were regionally metamorphosed to greenschist-grade phyllite and semischist in Late Cretaceous time. The occurrence consists of augite-porphyritic, Jurassic or Cretaceous, metatuff (greenstone) containing about five percent of disseminated sulfides, mainly pyrite and chalcopyrite (Karl, 1992). The greenstone is cut by quartz veins up to about 2 feet thick. A sample of the greenstone contained 3 ppm Ag, 200 ppm Cu, 100 ppm Co, 150 ppm Cr, and 150 ppm Ni (Karl, 1992, loc. 13).
  • Age = Disseminated sulfide mineralization may in part be cogenetic with Upper Jurassic or Cretaceous deposition of the metatuff (greenstone) hostrock. Fissure veins probably are Late Cretaceous or younger.

Economic information about the deposit and operations

Development status Occurrence

Mining district

District name Ketchikan

Comments on the workings information

  • Workings / Exploration = A sample of the greenstone contained 3 ppm Ag, 200 ppm Cu, 100 ppm Co, 150 ppm Cr, and 150 ppm Ni (Karl, 1992, loc. 13).

Reference information

Bibliographic references

  • Deposit

    Berg, H.C., 1972, Geologic map of Annette Island, Alaska: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-684, 8 p., 1 sheet, scale 1:63,360,

  • Deposit

    Berg, H.C., Elliott, R.L., and Koch, R.D., 1988, Geologic map of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska: U.S. Geological Survey Mineral Investigations Series Map MF-1807,27 p., scale 1:250,000.

  • Deposit

    Karl, S.M., 1992, Map and table of mineral deposits on Annette Island, Alaska: U.S. Geological Survey Open-File Report 92-690, 57 p., 1 map, scale 1:63,360.

Comments on the references

  • Primary Reference = Karl, 1992

General comments

Subject category Comment text
Deposit Model Name = In part, possibly low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a); in part, disseminated sulfide deposit of volcanogenic? origin.

Reporter information

Type Date Name Affiliation Comment
Reporter 07-JUL-99 H.C. Berg U.S. Geological Survey

Beyond USGS

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

Maps centered on this site

Authoritative Alaska resources

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