|Quadrangle map, 1:250,000-scale||MF|
|Quadrangle map, 1:63,360-scale||C-1|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The prospect site is on North Marble Island in Glacier Bay about 3.5 miles southwest of Sandy Cove. The location is uncertain; MacKevett and others (1971) did not find Reed's (1938) or Rossman's (1963) locations. The island is only about 0.4 mile long and 0.2 mile wide, and the location is probably correct to about 0.10 mile. The occurrence is location number 50 of Cobb (1972).|
North Marble Island is underlain mainly by crystalline marble that is part of a major marble unit exposed on several islands in Glacier Bay. They include Willoughby, Francis, and Drake Islands as well as North and South Marble Islands. The carbonate-rich section is primarily Devonian in age (MacKevett and others, 1971; Brew and others, 1978). The age of metamorphism and mineralization is probably Cretaceous. Assuming that the area is underlain by the granitic batholith of Cretaceous age that characterizes this province.Small sulfide (chalcopyrite, covellite, magnetite, pyrite, pyrrhotite?, and/or sphalerite) pods, commonly associated with mafic dikes, are widely distributed throughout the province. On North Marble Island, sulfide pods as much as 1.5 ft wide and 15 feet long occur in marble near mafic dikes. The sulfides also occur on joint faces within the dikes (Reed, 1938, p. 69). A mass of sphalerite and magnetite at an unspecified contact (?) was reported by Rossman (1963, p. K51).
|Geologic map unit||(-136.062856000346, 58.6716310897836)|
|Mineral deposit model||Distal hydrothermal replacement possibly related to subjacent granitic intrusions of Cretaceous age.|
|Age of mineralization||Cretaceous?|
|Workings or exploration||No workings. One claim reportedly located for nickel by S. H. Vevelstad before 1930. Burchard (1914, 1920), who investigated the area for the marble resource, reported mafic or lamprophyric dike rocks cutting marble.|
|Indication of production||None|
The site is in Glacier Bay National Park and Preserve.The first known metallic prospect staked on the island was by S. H. Vevelstad before 1930, who reportedly staked it for nickel. Mr. Vevelstad was an experienced prospector, better known for his discoveries of nickel-copper deposits in the Bohemia Basin area in the Sitka quadrangle.
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.
Burchard, E.F., 1914, Marble resources of the Juneau, Skagway, and Sitka districts, Alaska: U.S. Geological Survey Bulletin 592-C, p. 95-107.
Burchard, E.F., 1920, Marble resources of southeastern Alaska: U.S. Geological Survey Bulletin 682, 118 p.
Cobb, E.H., 1972, Metallic mineral resources map of the Mount Fairweather quadrangle, AK: U.S. Geological Survey Miscellaneous Field Study Map MF-436, 1 sheet, scale 1:250,000.
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.
MacKevett, E.M., Jr., Brew, D.A., Hawley, C.C., Huff, L.C., and Smith, J.G., 1971, Mineral resources of Glacier Bay National Monument, Alaska: U.S. Geological Survey Professional Paper 632, 90 p., 12 plates, scale 1:250,000.
Reed, J.C., 1938, Some mineral deposits of Glacier Bay and vicinity, Alaska: Economic Geology, v. 33, p. 52-80.
|Reporters||C.C. Hawley (Hawley Resource Group)|
|Last report date||1/3/1999|