|Quadrangle map, 1:250,000-scale||OP|
|Quadrangle map, 1:63,360-scale||A-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Dodge Creek is a short, north-flowing tributary of the Innoko River. The junction of Dodge Creek and the Innoko River lies approximately one mile west-northwest of the town of Ophir. The coordinates are at the mine along Dodge Creek marked on the U.S. Geological Survey Ophir A-2 topographic map (1954, minor revisions 1955), in the NW1/4 sec. 22, T. 27 S., R. 12 E., Kateel River Meridian. Dodge Creek is location 12 of Cobb (1972 [MF 367]). The location is accurate within 500 feet.|
The bedrock in the vicinity of Dodge Creek consists of sandstone, shale, and siltstone, and several small monzonite intrusive bodies (Chapman and others, 1985).
Gold in Dodge Creek is reportedly deep (Brooks, 1916). Heavy minerals in placer concentrates include magnetite, ilmenite, siderite, pyrite, amphibole, pyroxene, and zircon (Bundtzen and others, 1987). The source of the gold may be bimodal dike swarms, peraluminous rhyolite, and alkali-calcic monzonitic intrusive rocks in the Ophir area (Bundtzen and others, 1987).Gold was discovered on Dodge Creek in 1915 and mining probably began in 1916 (Brooks, 1916). Mining continued intermittently until possibly as recent as 1962. The estimated production from Dodge Creek is 408 ounces of gold and 40 ounces of silver (Bundtzen and others, 1987). The gold was 911 fine (Metz and Hawkins, 1981).
|Geologic map unit||(-156.568264960416, 63.1388700264719)|
|Mineral deposit model||Placer Au (Cox and Singer, 1986; model 39a)|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary. The placer gold is probably derived from Cretaceous or Tertiary intrusive rocks (Bundtzen and others, 1987).|
|Workings or exploration||Gold was discovered on Dodge Creek in 1915 and mining probably began in 1916 (Brooks, 1916). Mining continued intermittently until possibly as recent as 1962.|
|Indication of production||Yes; small|
|Production notes||The estimated production from Dodge Creek is 408 ounces of gold and 40 ounces of silver (Bundtzen and others, 1987).|
Brooks, A.H., 1916, Mineral resources of Alaska, report on progress of investigations in 1915: U.S. Geological Survey Bulletin 642, 279 p.
Bundtzen, T.K., Cox, B.C., and Veach, N.C., 1987, Heavy mineral provenance studies in the Iditarod and Innoko districts, western Alaska: Alaska Division of Geological and Geophysical Surveys Public-Data File 87-16, 25 p.
Chapman, R.M., Patton, W.W., and Moll, E.J., 1985, Reconnaissance geologic map of the Ophir quadrangle, Alaska: U.S. Geological Survey Open-File Report 85-203, 19 p., 1 sheet, scale 1:250,000.
Cobb, E.H., 1972, Metallic mineral resources map of the Ophir quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-367, 1 sheet, scale 1:250,000.
Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction material) in the Iditarod and Ophir quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-576, 101 p.
Metz, P.A., and Hawkins, D.B., 1981, A summary of gold fineness values from Alaska placer deposits: University of Alaska, Fairbanks, Mineral Industry Research Laboratory Report No. 45, 56 p.
|Last report date||8/7/2001|