Unnamed Occurrence (ARDF - ID056; south of upper Caribou Creek), Iditarod Mining District, Yukon-Koyukuk Census Area, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - ID056; south of upper Caribou Creek)	- not defined -
Iditarod Mining District	Mining District
Yukon-Koyukuk Census Area	Census Area
Alaska	State
USA	Country

Location: This occurrence is 0.2 mile southeast of hill 1,850 on a north-facing knob in the headwaters of Caribou Creek. The occurrence at an elevation of about 1,600 feet in the SW1/4 SW1/4 section 18, T. 28 N., R. 46 W., of the Seward Meridian. The location is accurate.
Geology: This occurrence is a zone of extensive tourmaline-calcite-chlorite alteration in intermediate dikes that intrude shale and sandstone of the Upper Cretaceous, Kuskokwim Group (Miller and Bundtzen, 1994; Miller, Bundtzen, and Gray, 2005). The occurrence is of uncertain size and orientation. Grab samples contain up to 200 parts per million (ppm) tin, 500 ppm zinc, 500 ppm antimony, 480 ppm arsenic, 200 ppm lead, 46 ppm bismuth, and 1,000 parts per billion (ppb) silver (McGimsey and others, 1988).
Workings: The occurrence was sampled by the U.S. Geological Survey in the 1980s (McGimsey and others, 1988).
Age: Unknown; the dikes that intrude the Upper Cretaceous Kuskokwim Group in the area are undated.
Alteration: Development of tourmaline-chlorite-calcite greisen.

Commodities (Major) - Bi, Sn; (Minor) - Ag, As, Pb, Sb, Zn
Development Status: None
Deposit Model: Sn-polymetallic deposit or Polymetallic vein (Cox and Singer, 1986; model 20b o

Other Databases

Link to USGS - Alaska:	ID056

Other Regions, Features and Areas containing this locality

References