|Quadrangle map, 1:250,000-scale||MF|
|Quadrangle map, 1:63,360-scale||B-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The occurrence is uncertainly located. It is either about two miles north of Mt. Marchainville at an elevation between 2500-3000 feet (NE 1/4, section 20, T 39 S., R. 51 E., of the Copper River Meridian) or about about 0.5 mile west-southwest of that location. The occurrence is number 83 of MacKevett and others (1971) and location 16 of Kimball and others (1978).|
Geologic descriptionIlmenite and magnetite, accompanied by subordinate chalcopyrite and pyrrhotite, occur in heavily iron-stained masses near the south contact of the Crillon-LaPerouse layered mafic-ultramafic intrusion (Brew and others, 1978). The layered intrusive was emplaced in rocks of the Chugach terrane (Berg and others, 1972). The first reports of the occurrences were by Rossman (1963, B 1121-F); further reports were made by MacKevett and others (1971, p. 72-73) and Kimball and others (1978, p. C112).
|Geologic map unit||(-137.02190634935, 58.4796341683143)|
|Mineral deposit model||Heavy-mineral segregations near basal contact of synorogenic layered mafic intrusive of Tertiary age (Foley and others, 1997).|
|Age of mineralization||Tertiary.|
|Alteration of deposit||Conspicuous secondary iron-staining.|
|Workings or exploration||Surface exposures only; knowledge is partly based on aircraft fly-by because of the extremely rough topography.|
|Indication of production||None|
Additional commentsThe occurrences are in extremely rugged country in the south part of the Crillon-LaPerouse intrusion in Glacier Bay National Park and Preserve.
Berg, H.C., Jones, D.L., and Richter, D.H., 1972, Gravina-Nutzotin Belt--Tectonic significance of an upper Mesozoic sedimentary and volcanic sequence in southern and southeastern Alaska: U.S. Geological Survey Professional Paper 800-D, p. D1-D24.
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.
Foley, J.Y., Light, T.D., Nelson, S.W., and Harris, R.A., 1997, Mineral occurrences associated with mafic-ultramafic and related alkaline complexes in Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 396-449.
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.
|Reporters||C.C. Hawley (Hawley Resource Group)|
|Last report date||4/5/1999|