|Quadrangle map, 1:250,000-scale||HE|
|Quadrangle map, 1:63,360-scale||A-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Green Spike prospect is at an elevation of about 4,500 feet, at the southwest head of East Fork Chulitna River. The map site is about 2.75 miles east southeast of VABM 5854 (Alf), in the northwest corner of sec. 15, T. 21 S., R. 7 W., of the Fairbanks Meridian. The accuracy of this location is within 1,000 feet. This is locality D4 of Balen (1990: OFR 34-90).|
Geologic descriptionThe Green Spike prospect is at the contact between a Tertiary granitic pluton and a slightly younger (Oligocene) complex of hypabyssal felsic dikes and remnants of a rhyolite flow. Both the granite and younger complex cut Jurassic to Cretaceous metamorphosed graywacke. The deposit is in the rhyolite, and consists of quartz veins containing cassiterite, chalcopyrite, molybdenite, pyrite, and sphalerite. Samples assay 0.48% copper, 819 ppm zinc, 0.4 ounce of silver per ton, 13 ppm tin, and 25 ppm molybdenum (Balen and others, 1991). The high molybdenum-tin-silver values, the evolved intrusive host-rocks, and their younger age distinguish this deposit from the copper-gold-rich deposits on the other side of the Chulitna Valley (for example, HE043).
|Geologic map unit||(-148.887264314803, 63.0995321003001)|
|Mineral deposit model||Porphyry Sn (Cox and Singer, 1986; 20a)|
|Mineral deposit model number||20a|
|Age of mineralization||Volcanic rocks hosting the deposit are considered Oligocene (Wilson and others, 1998).|
|Workings or exploration||Surface sampling only.|
|Indication of production||None|
Balen, M.D., 1990, Geochemical sampling results from Bureau of Mines investigations in the Valdez Creek mining district, Alaska: U.S. Bureau of Mines Open-File Report 34-90, 218 p., 2 sheets, scale 1:63,360.
Balen, M.D., 1991, Executive summary of the Bureau of Mines investigations in the Valdez Creek mining district, Alaska: U.S. Bureau of Mines Special Publication 1991, 53 p.
|Reporters||N. Van Wyck (Stevens Exploration Management Corporation)|
|Last report date||4/7/2000|