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Evelyn Lee

Prospect in Alaska, United States with commodities Silver, Gold, Copper
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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 10001396
MRDS ID A012138
Record type Site
Current site name Evelyn Lee

Geographic coordinates

Geographic coordinates: -149.26334, 67.65972 (WGS84)
Relative position This site is at an elevation of about 4,400 feet on a ridge between Sheep Creek and Spruce Creek west of Horace Mountain (NW1/4 sec. 25, T. 33 N., R. 8 W., of the Fairbanks Meridian). Its location is taken from maps published on the Internet website of the current operator, Ventures Resource Corp. (URL http://www.venturesresource.com/). The known mineralized area extends approximately 1/2 mile northeast and southwest of the reference point. The location is accurate within a 1/2-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-5(quadrangle 1:63,360 scale)

Chandalar N(quadrangle 1:100,000 scale)

Chandalar(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Alaska(hydrologic region)

Federal lands

Doyon, Limited(ANCSA Region)

ANCSA Region NTVPIC(Type of land area)

NTVPIC(Federal land areas administered by NTVPIC)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Gold Primary
Copper Primary

Materials information

Materials Type of material
Bornite Ore
Chalcopyrite Ore
Gold Ore
Pyrite Ore

Alteration

  • (Local) Potassic and sericitic alteration in the meta-igneous rocks. Calc-silicate hornfels.

Mineral occurrence model information

Model code 58
USGS model code 18a
Deposit model name Porphyry Cu, skarn-related
Mark3 model number 9

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Ultramafic Intrusive Rock > Hornblendite
    Stratigraphic age (youngest) Late Devonian
  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Marble
    Rock unit name Skajit Limestone
    Rock description Skajit Limestone

Nearby scientific data

(1) -149.26334, 67.65972
ListMap

Economic information

Comments on the geologic information

  • Geologic Description = The Evelyn Lee prospect is one of a number of Cu skarn deposits in the Chandalar area which have been described in general by Newberry and others (1986). They are all located northwest of the belt of the Devonian(?) Horace Mountain granitic rocks. Many of the Cu skarns exhibit both prograde garnet/pyroxene and retrograde epidote and actinolite mineral assemblages. Newberry and others (1986) stateed that the mineralogy, mineralization, and alteration of these skarns tend to place them in the category of continental-margin, porphyry-related copper skarns. ? Dillon and others (1996) mapped the area as Devonian Horace Mountain granite gneiss and Devonian felsic schists with proximal tactite and calcareous hornfels. The Devonian felsic schists are interpreted by Dillon and others (1996) as hypabyssal to plutonic in origin, but they are not included in the Horace Mountain plutonic assemblage. Early descriptions (early to mid-1970s) of the Evelyn Lee prospect described chalcopyrite, bornite, and pyrite in isolated skarn bodies that occur in marble in the Skajit Limestone near or at the contact with Devonian hornblende granodiorite porphyry. Skarn bodies were reported to be as much as 100 m long and 10 m wide. Copper grades as high as 10 percent Cu were obtained from outcrops. Altered and pyritized meta-granodiorite bodies are spatially associated with the mineralized skarns. ? Mineralization on the property has been described by Ventures Resource Corp. as consisting of pyrite, chalcopyrite, and bornite with silver and gold found in metamorphosed VMS, skarn, and sheared granitic-hosted deposits. Ventures Resource considers the target model for this prospect to be copper-gold skarn mineralization related to copper porphyry-type intrusives. The host rocks are volcanogenic calc-schist, chloritic calc-schist, limestone and dolomite, and intensely sheared granitic intrusive. Structurally, the host rocks form a broad syncline intruded along the keel by granodiorite. Assays include grades of 9.9 percent Cu and 8.17 ounces of silver per ton from a 7-foot-thick zone of sulfides in skarn, and a 5-foot surface sample which grades 5.6 percent Cu and 0.04 ounce of gold per ton. A core sample assayed 3.5 percent Cu over a 23.5-foot drill intercept.
  • Age = Devonian based on reported Early Devonian Pb/Pb zircon ages from the associated Baby Creek batholith and Horace Mountain plutons (Dillon and others, 1996).

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Active

Mining district

District name Koyukuk

Comments on the reserve resource information

  • Reserves = Estimates of potential for this property ranges from about 1 million metric tons of 5 percent Cu (DeYoung, 1978) to 'tens of million of tons grading 2 percent to 5 percent Cu with gold and silver credits' (Ventures Resource Corporation website, 1998, URL http://www.venturesresource.com/).

Comments on the workings information

  • Workings / Exploration = Claims were staked in 1969 and 1970. The property was selected by Doyon, Limited (an Alaska Native Corporation) in the early 1970s as part of Alaska Native Claims Settlement Act (ANCSA) settlement. In 1998 the Evelyn Lee property was being explored by Ventures Resource Corporation under the terms of an exploration agreement with the owner, Doyon, Limited. Sampling results from a large soil sample grid (approximately 5,000 feet x 2,500 feet ) shows extensive areas of more than 500 ppm Cu in soil (Ventures Resource Corporation,1998). A grade 9.9 percent Cu and 8.17 ounces of Ag per ton of was obtained from sampling of a 7-foot-thick sulfide layer in skarn. Two shallow core drill holes have explored one of the copper soil anomalies. This drilling encountered mineralization that assayed 3.5 percent copper from surface to 23.5 feet and 2 percent copper from surface to 18 feet.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Ventures Resource Corporation, 1998

General comments

Subject category Comment text
Deposit Model Name = Porphyry Cu, skarn-related deposits (Cox and Singer, 1986; model 18a)
Deposit Other Comments = See also: Venus (CH065), Victor (CH064), Eva (CH063), and Geroe Creek (CH053) prospects. Alaska Kardex No. KX-31-53H (Kardex is a card file mining claim information system located at the State of Alaska DNR Public Information Center in Fairbanks).

Reporter information

Type Date Name Affiliation Comment
Reporter 17-NOV-1999 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.