|Quadrangle map, 1:250,000-scale||LH|
|Quadrangle map, 1:63,360-scale||B-1|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is on the north side of the upper Chilligan River within a small glacier-filled valley. It is at the toe of a south-flowing glacier, at an elevation of about 4,600 feet, and 1.5 miles north of Chilligan River. The map site is in the SE1/4 section 28, T 16 N, R 22 W, of the Seward Meridian. This is locality 15 of Cobb (1972 [MF 412]; 1976 [OF 76-485]) and location 30 of Gamble and others (1989). The location is probably accurate to within one-half mile.|
Geologic descriptionReed and Elliott (1970) reported that float in a medial moraine at this locality consists of silicified and sericitized quartz monzonite that contains 5 to 10 percent galena, sphalerite, and pyrite. The sulfide minerals are in clots as much as 2 cm in diameter and in thin veinlets up to 5 mm wide. Shear zones in nearby metasedimentary rocks contain galena and sphalerite. Sulfide-bearing samples contain up to greater than 20,000 ppm lead, greater than 10,000 ppm zinc, greater than 1,000 ppm tin, 2,000 ppm copper, and 150 ppm silver. The mineralization is near the contact between a Tertiary granitic pluton and Mesozoic metamorphic rocks.
|Geologic map unit||(-153.224013667409, 61.4444715627727)|
|Mineral deposit model||Polymetallic veins (Cox and Singer, 1986, model 22c)|
|Mineral deposit model number||22c|
|Age of mineralization||Tertiary. Mineralization occurs in Tertiary intrusive rocks and in shear zones in nearby metasedimentary rocks.|
|Alteration of deposit||Silicification? and sericite-pyrite replacement?|
|Workings or exploration||Reconnaissance sampling has been completed in this area (Reed and Elliott, 1970).|
|Indication of production||None|
Additional commentsThis occurrence is within Lake Clark National Park.
Cobb, E.H., 1972, Metallic mineral resources map of the Lime Hills quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-412, 1 sheet, scale 1:250,000.
Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-485, 101 p.
Cobb, E.H., and Reed, B.L., 1981, Summaries of data on and lists of references to metallic and selected nonmetallic mineral occurrences in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska; Supplement to Open-File Report 76-485; Part A, Summaries to January 1, 1981: U.S. Geological Survey Open-File Report 81-1343-A, 25 p.
Gamble, B.M., Bailey, E.A., and Reed, B.L., 1989, Gold occurrences near Snowcap Mountain, Lime Hills B-2 quadrangle, Alaska: U.S. Geological Survey Open-File Report 89-0646, 8 p.
|Reporters||Travis L. Hudson and Madelyn A. Millholland|
|Last report date||6/10/2001|