Houghton (ARDF #CR123) Ag, Au, Cu, Zn

Houghton

Prospect, Inactive

Commodities and mineralogy

Main commodities	Ag; Au; Cu; Zn
Ore minerals	chalcopyrite; copper; magnetite; pyrite; pyrrhotite; sphalerite
Gangue minerals	epidote; garnet

Geographic location

Quadrangle map, 1:250,000-scale	CR
Quadrangle map, 1:63,360-scale	B-2
Latitude	55.26366
Longitude	-132.62147
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	The Houghton prospect is about 0.8 mile north-northwest of Mount Jumbo. It is at an elevation of about 1,650 feet, about 0.3 mile east-southeast of the center of section 22, T. 76 S., R. 84 E., of the Copper River Meridian.

Geologic setting

Geologic description The Houghton is an old prospect that was discovered between 1900 and 1903 and was explored by several adits and surface workings prior to 1908 (Wright and Wright, 1905; Wright, 1915; Roppel, 1991). There has been little work since. The deposit consists of small, irregular pods of sulfides in garnet-epidote skarn. The skarn is about 65 feet thick and extends for several hundred feet along a faulted contact between Cretaceous granodiorite and marble of the Wales Group of Late Proterozoic or Cambrian age (Wright and Wright, 1908; Herreid and others, 1978; Maas and others, 1991, 1995). The ore minerals are mainly chalcopyrite, magnetite, and pyrite, with minor sphalerite, pyrrhotite, and native copper. Samples collected by Maas and others (1991, 1995) in the adits contained up to 2,630 parts per billion gold, 465 parts per million silver, and 10.44 percent copper, but the mineralization is restricted to small pods.
Geologic map unit	(-132.623125533437, 55.2633084466021)
Mineral deposit model	Cu-Fe skarn (Cox and Singer, 1986; model 18b).
Mineral deposit model number	18b
Age of mineralization	Related to nearby Cretaceous granodiorite.
Alteration of deposit	Mineralization associated with garnet-epidote skarn.

Production and reserves

Workings or exploration	The prospect was explored by three adits, 80, 100, and 200 feet long, and several surface trenches, mostly before 1908; and an aerial tram extended to down to Hetta Inlet. The property has been inactive since the 1920s.
Indication of production	None
Additional comments The Houghton prospect is on or surrounded by land that has been conveyed to the Sealaska Corporation, who hold the surface and subsurface rights, or the land is under application for transfer to them.

References

MRDS Number	A010112
References Cobb, E. H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Craig quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-869, 262 p. Herreid, Gordon, Bundtzen, T.K., and Turner, D.L., 1978, Geology and geochemistry of the Craig A-2 quadrangle, Prince of Wales Island, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Geologic Report 48, 49 p. Maas, K.M., Bittenbender, P E., and Still, J.C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U.S. Bureau of Mines Open-File Report 11-95, 606 p. Maas, K.M., Still, J.C., Clough, A.H., and Oliver, L.K., 1991, Mineral investigations in the Ketchikan mining district, Alaska, 1990: southern Prince of Wales Island and vicinity: U.S. Bureau of Mines Open-File Report 33-91, 139 p., 12 sheets, scale 1:63,360. Roppel, Patricia, 1991, Fortunes from the earth: Manhattan, Kansas, Sunflower University Press, 139 p. Wright, C.W., 1907, Lode mining in southeastern Alaska, in Brooks, A.H., and others, Report on progress of investigations of mineral resources of Alaska in 1906: U.S. Geological Survey Bulletin 314, p. 47-72. Wright, C.W., 1908, Lode mining in southeastern Alaska, 1907: U.S. Geological Survey Bulletin 345-B, p. 78-97. Wright, C.W., 1909, Mining in southeastern Alaska: U.S. Geological Survey Bulletin 379-B, p. 67-86. Wright, C.W., 1915, Geology and ore deposits of Copper Mountain and Kasaan Peninsula, Alaska: U.S. Geological Survey Professional Paper 87, 110 p. Wright, F.E., and Wright, C.W., 1905, Economic developments in southeastern Alaska, in Brooks, A.H., Report on Progress of Investigations of Mineral Resources of Alaska in 1904: U.S. Geological Survey Bulletin 259, p. 47-68. Wright, F.E., and Wright, C.W., 1908, The Ketchikan and Wrangell mining districts, Alaska: U.S. Geological Survey Bulletin 347, 210 p.
Reporters	D.J. Grybeck (Applied Geology)
Last report date	5/1/2004