|Quadrangle map, 1:250,000-scale||SR|
|Quadrangle map, 1:63,360-scale||D-7|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is located in the SE1/4 section 20, T. 8 N., R. 1 E., of the Seward Meridian. It is at an elevation of 3,700 to 4,200 feet, on a ridge above the head of a small, northwest-flowing tributary to Gulch Creek. This is location S-281 of Jansons and others (1984). The location is accurate to within a quarter of a mile.|
This occurrence consists of two narrow quartz veins, averaging 3 inches wide, that strike N35-50W and dip 40-55NE. The veins contain arsenopyrite, chalcopyrite, galena, sphalerite, stibnite, and gold. One vein can be traced along strike for 200 feet (Jansons and others, 1984). The veins are hosted in complexly folded and faulted, interbedded, locally iron-stained, slightly metamorphosed, silty to sandy graywacke, pebble conglomerate, and minor slate of the Valdez Group of Late Cretaceous age (Nelson and others, 1985). Several barren-appearing stockwork-type quartz veins also occur in the area.Twelve samples collected in 1981 by the U.S. Bureau of Mines assayed from a trace to 0.18 ounce of gold per ton and from a trace to 22.5 ounces of silver per ton. Other metal values, including arsenic, copper, lead, zinc, and antimony, ranged from none detected to 4,600 ppm (Hoekzema and Sherman, 1983).
|Geologic map unit||(-149.30775468287, 60.7627375141274)|
|Mineral deposit model||Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)|
|Mineral deposit model number||36a|
|Age of mineralization||Cretaceous or younger; the veins cut rocks of the Valdez Group of Late Cretaceous age.|
|Alteration of deposit||Local iron staining.|
|Workings or exploration||The U.S. Bureau of Mines discovered the occurrence in 1981. They collected 12 samples that assayed from a trace to 0.18 ounce of gold per ton and from a trace to 22.5 ounces of silver per ton (Jansons and others, 1984). Other metals values tested for included arsenic, copper, lead, zinc, and antimony. Antimony values ranged from a trace to 0.23 percent (Jansons and others, 1984).|
|Indication of production||None|
|Reserve estimates||The U.S. Bureau of Mines estimated reserves of 200 tons of ore containing 0.1 ounce of gold per ton and 20 ounces of silver per ton (Jansons and others, 1984).|
Additional commentsThe U.S. Bureau of Mines reported that other quartz veins occur in the area, but because of time limitations and precipitous terrane, they did not sample them (Hoekzema and Sherman, 1983). The Bureau recommended additional exploration.
Hoekzema, R.P., and Sherman, G.E., 1983, Mineral investigations in the Chugach National Forest, Alaska (Peninsula study area): U.S. Bureau of Mines in-house report; held at U.S. Bureau of Land Management Alaska State Office, Anchorage, 524 p.
Jansons, Uldis, Hoekzema, R.B., Kurtak, J.M., and Fechner, S.A., 1984, Mineral occurrences in the Chugach National Forest, southcentral Alaska: U.S. Bureau of Mines Mineral Land Assessment 5-84, 218 p., 2 sheets, scale 1:250,000.
|Reporters||Jeff A. Huber (Anchorage)|
|Last report date||2/4/2000|