Location: The prospect is located on a north-facing hillside about 5 miles northeast of Tetlin Junction. It is at about 3000 feet of elevation, in section 3, T. 19 N., R. 15 E., of the Copper River Meridian. It is location 20 of Singer and others (1976), and locality 1 of Eberlein and others (1977). It lies about 3.5 miles north of Ladue Peak. The location is known to within a mile.
Geology: The ASARCO prospect consists of silicified and deeply leached Tertiary quartz porphyry hypabyssal intrusive and extrusive rocks that contain disseminated molybdenite and copper sulfide minerals (Singer and others, 1976). The regional geology of the prospect consists of Tertiary felsic volcanics surrounded by undivided granitic rocks (Foster, 1970). The prospect lies within the eastern Yukon-Tanana Y1 subterrane of Foster and Keith (1994). Cities Services Mineral Corp. drilled three holes in the prospect in 1971, and then dropped the project (David Hedderly-Smith, oral communication, 1998). A rhyolite flow near the ASARCO prospect yielded an age of 55-60 Ma (Newberry and others, 1996).
Workings: Surface sampling, some sampling and drilling in 1970 and 1971.
Age: Early Tertiary (55-60 Ma), based on the prospect's similarity to the Taurus prospect (TC027) and the Pushbush prospect (TC024) nearby, as well as a radiometric date on a rhyolite flow near the prospect (Newberry and others, 1996).
Alteration: Alteration types include severe silicification and leaching of the hypabyssal intrusive (Singer and others, 1976).

Commodities (Major) - Cu, Mo
Development Status: None
Deposit Model: Porphyry Cu deposit (Cox and Singer, 1986; model 21a)

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Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.

ⓘ Copper

ⓘ Molybdenum

Mineral List

ⓘ Chalcopyrite ?

ⓘ Molybdenite

ⓘ Pyrite

3 valid minerals.

Detailed Mineral List:

ⓘ Chalcopyrite ?

Formula: CuFeS₂

References:

(2008) Alaska Resource Data File (ARDF) Open-File Report 2008-1225. US Geological Survey

ⓘ Molybdenite

Formula: MoS₂

References:

(2008) Alaska Resource Data File (ARDF) Open-File Report 2008-1225. US Geological Survey

ⓘ Pyrite

Formula: FeS₂

References:

(2008) Alaska Resource Data File (ARDF) Open-File Report 2008-1225. US Geological Survey

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘ	Chalcopyrite ?	2.CB.10a	CuFeS₂
ⓘ	Molybdenite	2.EA.30	MoS₂
ⓘ	Pyrite	2.EB.05a	FeS₂

List of minerals for each chemical element

S	Sulfur
S	ⓘ Chalcopyrite	CuFeS₂
S	ⓘ Molybdenite	MoS₂
S	ⓘ Pyrite	FeS₂
Fe	Iron
Fe	ⓘ Chalcopyrite	CuFeS₂
Fe	ⓘ Pyrite	FeS₂
Cu	Copper
Cu	ⓘ Chalcopyrite	CuFeS₂
Mo	Molybdenum
Mo	ⓘ Molybdenite	MoS₂

Other Databases

Link to USGS - Alaska:	TC001

Other Regions, Features and Areas containing this locality

North AmericaContinent

North America PlateTectonic Plate

North America PlatformPassive Margin
Yukon-Tanana lower DomainDomain

USA

Alaska
- Fortymile Mining DistrictMining District

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References

Cobb, E.H., and Eberlein, G.D., 1980, Summaries of data on and lists of references to metallic and selected nonmetallic mineral deposits in the Big Delta and Tanacross quadrangles, Alaska: U.S. Geological Survey Open-File Report 80-1086, 77 p. Eberlein, G.D., Chapman, R.M., Foster, H.L., and Gassaway, J.S., 1977, Map and table describing known metalliferous and selected nonmetalliferous mineral deposits in central Alaska: U.S. Geological Survey Open-File Report 77-168-D, 132 p., 1 sheet, scale 1:1,000,000. Foster, H.L., 1970, Reconnaissance geologic map of the Tanacross quadrangle, Alaska: U.S. Geological Survey Miscellaneous Geological Investigations Map I-593, 1 sheet, scale 1:250,000. Foster, H.L., and Keith, T.E.C., 1994, Geology of the Yukon-Tanana area of east-central Alaska: in Plafker, G. and Berg, H.C., eds, The geology of North America, vol. G-1, The geology of Alaska: Geological Society of America, p. 205-240. Gill, R., 1977, Geology and mineral deposits of the southwest quarter of the Tanacross D-1 quadrangle, Alaska: Golden, Colorado School of Mines, M.Sc. thesis, 129 p. Newberry, R.J., Layer, P.W., Burleigh, R.E., and Solie, D.N., 1996, New 40Ar/39Ar dates for intrusions and mineral prospects in the eastern Yukon-Tanana terrane, Alaska - Regional patterns and significance, in Gray, J.E., and Riehle, J.R., eds., Geological Studies in Alaska by the U.S. Geological Survey, 1996: U.S. Geological Survey Professional Paper 1595, p. 131-159. Nokleberg, W.J., Bundtzen, T.K., Berg, H.C., Brew, D.A., Grybeck, D.J., Robinson, M.S., Smith, T.E., and Yeend, W., 1987, Significant metalliferous lode deposits and placer districts of Alaska: U.S. Geological Survey Bulletin 1786, 104 p., 2 plates, scale 1:5,000,000. Singer, D.A., Curtin, G.C., and Foster, H.L., 1976, Mineral resources map of the Tanacross quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-767-E, 1 sheet, scale 1:25,000.

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ASARCO; Tok; Dennis Prospect, Southeast Fairbanks Census Area, Alaska, USAiRegional Level TypesASARCO; Tok; Dennis ProspectProspect Southeast Fairbanks Census AreaCensus Area AlaskaState USACountry function showexplain() { $("#locexplain").toggle(); if (typeof movemap === "function") movemap(); }

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Commodity List

Mineral List

Detailed Mineral List:

Gallery:

List of minerals arranged by Strunz 10th Edition classification

List of minerals for each chemical element

Other Databases

Other Regions, Features and Areas containing this locality

References

ASARCO; Tok; Dennis Prospect, Southeast Fairbanks Census Area, Alaska, USA i
Regional Level Types
ASARCO; Tok; Dennis Prospect Prospect
Southeast Fairbanks Census Area Census Area
Alaska State
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