|Quadrangle map, 1:250,000-scale||MF|
|Quadrangle map, 1:63,360-scale||D-3|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The occurrence is on the east side of Hill 4650 at an elevation of about 4000 feet at the head of Scidmore Glacier. It is about 1 mile east of Reid Glacier, at a point approximately 2.3 miles above the nose of the glacier. The location is probably accurate to within 200 feet vertically and about 0.1 mile horizontally. The location is number 69 of MacKevett and others (1971) and number 48 of Kimball and others (1978).|
Geologic descriptionThe area is underlain by mixed schist, phyllite, and marble of Paleozoic age within a terrane intruded by granitic rocks of Cretaceous age (Brew and others, 1978, pl. 1A). In the area of the mineral occurrence, two conspicuously iron-stained zones as much as 25 feet thick cut tightly folded metasedimentary rocks, mostly marble. Pyrite-bearing quartz veins 1-2 feet in thickness locally cut the iron-stained zones. Chalcopyrite is present locally; a float sample of quartz vein contained 1000 ppm copper, and a 15-foot chip sample of a sulfidized zone contained 300 ppm copper and 7 percent iron; gold and silver were not detected.
|Geologic map unit||(-136.761861419369, 58.8126047968394)|
|Mineral deposit model||Low-sulfide quartz vein and disseminated sulfides in altered rock.|
|Age of mineralization||Probably Cretaceous, related to the intrusion of granitic rocks.|
|Workings or exploration||Surface exposures only; an iron stained zone 15 feet thick contained 300 ppm copper; a quartz vein (float) contained 1000 ppm copper (MacKevett and others, 1971, table 9).|
|Indication of production||None|
Additional commentsMineralization related to Cretaceous granitic event. The area is in Glacier Bay National Park and Preserve.
Brew, D.A., Johnson, B.R., Grybeck, D., Griscom, A., Barnes, D.F., Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources of the Glacier Bay National Monument Wilderness Study Area, Alaska: U.S. Geological Survey Open-File Report 78-494, 670 p., 7 sheets.
Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources, in Brew, D. A., and others, Mineral resources of the Glacier Bay National Monument wilderness study area, Alaska: U.S. Geological Survey Open-File Report 78-494, p. C1-C375.
|Reporters||C.C. Hawley (Hawley Resource Group)|
|Last report date||4/9/1999|