Grassy Island Prospect

Unknown in Koochiching county in Minnesota, United States with commodity Gold
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Public Land Survey System information
  6. Commodities
  7. Materials information
  8. Nearby scientific data
  9. Geologic structures
  10. Controls for ore emplacement
  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 10082805
MRDS ID W062155
Record type Site
Current site name Grassy Island Prospect

Geographic coordinates

Geographic coordinates: -93.21467, 48.61806 (WGS84)
Location accuracy 1000(meters)
Relative position VEINS OCCUR ON THE EAST END OF GRASSY ISLAND IN RAINY LAKE, ABOUT EIGHT MILES EAST OF FORT FRANCES, ONTARIO, CANADA., Est Estimated Location Taken From 1:50,000 Scale Map, Est Estimated Location Taken From 1:50,000 Scale Map

Site location context

Political divisions (FIPS codes)

Koochiching(county)

Minnesota(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Island View(quadrangle 1:24,000 scale)

International Falls(quadrangle 1:100,000 scale)

International Falls(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Rainy Lake(hydrologic unit)

Rainy(hydrologic accounting unit)

Rainy(hydrologic subregion)

Souris-Red-Rainy(hydrologic region)

Federal lands

Superior National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States Minnesota Koochiching

Public Land Survey System information

Meridian Township Range Section Fraction State
71N 22W 30 Minnesota

Comments on the location information

  • NOT SHOWN ON MAP I-1927.

Commodities

Commodity Importance
Gold Primary

Materials information

Materials Type of material
Gold Ore
Chlorite Gangue
Pyrite Gangue
Quartz Gangue
Sericite Gangue
Specularite Gangue
Tourmaline Gangue

Nearby scientific data

(1) -93.21467, 48.61806

Economic information

Geologic structures

Type of structure Regional
Structure description In The Quetico Subprovince Of The Superior Province. The Rainy Lake Area Lies Within A Dextral Wrench (Shear) Zone Bounded On The North By The Quetico Fault And On The South By The Rainy Lake-Seine River Fault.

Controls for ore emplacement

  • Sims And Day (1992) Note That The Fundamental Regional Control On Gold Deposits In The Superior Province Is Transcurrent And Oblique Slip-Shear Deformation Zones That Formed In Late Archean Time.

Economic information about the deposit and operations

Commodity type Metallic
Deposit size Small
Significant No

Mining district

District name Rainy Lake

Comments on development

  • EXPLORATION FOR GOLD DEPOSITS IN THE REGION HAS BEEN HAMPERED BY A GENERALLY THIN, DISCONTINUOUS MANTLE OF PLEISTOCENE GLACIAL DEPOSITS. ; ECON.COM: GOLD MINES IN THE CANADIAN PART OF THE RAINY LAKE DISTRICT HAD PRODUCED MORE THAN ONE MILLION DOLLARS WORTH OF GOLD BY 1937, MOSTLY FROM HYPOTHERMAL VEINS LIKE THE ONE AT THE LITTLE AMERICAN MINE AND AT OTHER MINES IN THE AREA.

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit GROUT (1937) CLASSIFIED THESE DEPOSITS AS OF PROBABLE HYPOTHERMAL ORIGIN.
Deposit THE OCCURRENCE OF LARGE GOLD DEPOSITS IN CANADA SUGGESTS THAT THE GREENSTONE-GRANITE TERRANES OF MINNESOTA ARE FAVORABLE FOR THE OCCURRENCE OF IMPORTANT GOLD DEPOSITS.
Deposit GROUT (1937) DID NOT GIVE A MORE SPECIFIC NAME FOR THIS PROSPECT.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-DEC-95 Sutphin, David M. (Cannon, W. F.) U.S. Geological Survey
Updater 01-MAR-97 Sutphin, David M. U.S. Geological Survey
Editor 01-MAY-97 Mason Jr., G.T. U.S. Geological Survey

Beyond USGS

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