Unnamed Prospect (ARDF - ID038; east of upper Yankee Creek), Iditarod Mining District, Yukon-Koyukuk Census Area, Alaska, USAi

Regional Level Types
Unnamed Prospect (ARDF - ID038; east of upper Yankee Creek)	- not defined -
Iditarod Mining District	Mining District
Yukon-Koyukuk Census Area	Census Area
Alaska	State
USA	Country

Location: This prospect is on the end of a northwest-trending ridge southeast of Yankee Creek at an elevation of about 1,400 feet. It is about 0.5 mile east of the center of section 1, T. 33 N. R. 38 W., of the Seward Meridian. The location is accurate.
Geology: This prospect is in altered, quartz-feldspar porphyry dikes and sills that intrude shale and siltstone of the Upper Cretaceous, Kuskokwim Group (Bundtzen and Laird, 1983; Miller and Bundtzen, 1994). The prospect is poorly exposed and the data is based on examination of float, rubble, and geochemical anomalies in rock and soil surveys (North Star Exploration Ltd.; information brochure, 1999). The dikes and sills vary from about 15 to 100 feet thick. The intrusive rocks are cut by hairline fractures filled with quartz and very fine-grained sulfides, mainly arsenopyrite and subordinate pyrite. Iron carbonates, including siderite, are present (Galey and others, 2002). Rock samples collected from mineralized zones contain as much as 5,725 parts per billion (ppb) gold and up to 6,000 parts per million (ppm) arsenic. Soil samples contain up to 250 ppb gold (North Star Exploration, Ltd., press release, Feb. 14, 2002; S. Dashevsky and T.K. Bundtzen, unpublished data, 2002).
Workings: Most of the exploration was in 1998 and 2001 by North Star Exploration, Inc. (Hinderman and others, 1999; Galey and others, 2002; EMEX Corporation press release, February 14, 2002).
Age: Undated; the intrusion on nearby French Joe Mountain has a 40Ar/39Ar age of 71.3 Ma (T.K. Bundtzen, unpub. data, 1999).
Alteration: Phyllic and potassic alteration; secondary biotite has developed in the intrusive rocks.

Commodities (Major) - Au; (Minor) - As
Development Status: None
Deposit Model: Low sulfide gold-quartz vein or Porphyry gold-copper deposit; (Cox and Singer,

Other Databases

Link to USGS - Alaska:	ID038

Other Regions, Features and Areas containing this locality

References