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Summit

Prospect in Alaska, United States with commodities Silver, Gold, Copper, Lead, Antimony
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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 10001771
MRDS ID A012561
Record type Site
Current site name Summit

Geographic coordinates

Geographic coordinates: -148.20329, 67.53974 (WGS84)
Relative position The Summit lode is at an elevation of about 4,800 feet, approximately 1/2 mile south of Little Squaw Peak, between Little Squaw Peak and peak 5072 (St. Marys Peak as shown on fig. 2 in Chipp, 1970) in SW1/4 sec. 3, T. 31 N., R. 3 W., of the Fairbanks Meridian. The location is accurate within a 1/4-mile radius.

Site location context

Political divisions (FIPS codes)

Yukon-Koyukuk(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Chandalar C-3(quadrangle 1:63,360 scale)

Chandalar N(quadrangle 1:100,000 scale)

Chandalar C(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Alaska(hydrologic region)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Gold Primary
Copper Secondary
Lead Secondary
Antimony Critical Secondary

Materials information

Materials Type of material
Arsenopyrite Ore
Gold Ore
Scorodite Ore
Quartz Gangue

Alteration

  • (Local) Oxidation of vein material produces scorodite and limonite.

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) Devonian

Nearby scientific data

(1) -148.20329, 67.53974
ListMap

Economic information

Comments on the geologic information

  • Geologic Description = The Summit lode is one of the four principal auriferous quartz vein systems in the Chandalar area. The Summit vein system, like the others in the area, is localized along steeply-dipping, northwest-trending normal faults in Devonian quartz-muscovite schist, phyllite, and quartzite, intruded by Devonian mafic sills and dikes (Chipp, 1970). In general, the veins in the Chandalar area are less than 10 feet thick and are discontinuous, pinching out within a few hundred feet or less. The veins are composed principally of white crystalline to microcrystalline quartz, and their sulfide content is generally less than 5 percent. The principal sulfides (in relative order of abundance) are arsenopyrite, galena, sphalerite, and pyrite. Scorodite and limonite occur commonly as oxidation products. The quartz veins exhibit evidence of shearing, indicating that the veins were emplaced before or during fault movement. Major structural features in the area include large-scale northeast-trending anticlines and synclines, northeast-trending thrusts, and the northwest-trending, high-angle cross faults.? the Summit lode follows the Summit fault and the strikes N80W and dips 75 to 80 degrees south. Early workings on the property exposed a vein 1.5 to 2 feet wide. A sample from these workings was reported to have assayed $54 of gold per ton (Maddren,1913). Dump samples of vein material collected by Chipp (1970) contained abundant arsenopyrite and scorodite in sheared and brecciated quartz; assays of these samples returned values of 0.5 to 6.6 ppm Au. Ashworth (1983) described two generations of quartz at the Summit lode. The older generation is coarsely crystalline, massive, white quartz. It is in the hanging wall and is as much as 4 feet wide. It contains less than 5 percent sulfides and little gold. The younger generation pinches and swells; it adjoins the older veins, but typically follows in the footwall. It is generally finer grained and contains bands accentuated by smeared graphite and arsenopyrite. Scorodite is common, and free gold occurs as blebs and occasional wires. ?The genesis of the gold deposits in the Chandalar district is still in question. Various authors have hypothesized genetic links to a variety of felsic and mafic igneous rocks from which the gold was remobilized during metamorphism (Mertie, 1925; Boadway, 1933; Chipp, 1970; Dillon, 1982).
  • Age = Middle Cretaceous based on arguments by Dillon (1982) that the age of emplacement of the gold-bearing quartz veins of the Koyukuk and Chandalar districts was between the Neocomian metamorphism of the Devonian host rocks and their erosional unroofing and cooling in Albian time.
  • Age = Host rock is Devonian.

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Chandalar

Comments on the workings information

  • Workings / Exploration = Maddren (1913) reported a 54-foot-deep shaft and a 72-foot drift along the vein. Prospect pits have been dug along the Summit fault/vein system as far east as the pass between Big Creek and McClellan Creek and west along the spur going into Big Squaw Creek. Heiner and Wolff (1968) report that there was some development work in the 1950s and a small mill was established for the ore in the headwaters of Big Creek.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Chipp, 1970

General comments

Subject category Comment text
Deposit Model Name = Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)
Deposit Other Comments = See also: Mikado (CH045), Little Squaw(CH040), Star(CH042).

Reporter information

Type Date Name Affiliation Comment
Reporter 17-NOV-99 J.M. Britton 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.