Unnamed Occurrence (ARDF - MM163; on a tributary to upper Pirate Creek), Kantishna Mining District, Denali Borough, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - MM163; on a tributary to upper Pirate Creek)	- not defined -
Kantishna Mining District	Mining District
Denali Borough	Borough
Alaska	State
USA	Country

The occurrence is in Denali National Park and Preserve.
Location: This occurrence is on the west side of a north-flowing tributary of Pirate Creek about a mile west of Muldrow Glacier. It is probably within a few hundred feet of the north end of the section line between sections 29 and 30, T. 18 S., R. 15 W., Fairbanks Meridian. The occurrence is included in the description of the Twin Hills lode (MM168) by Cobb (1972, location 35 [MF 366]; 1980 [OFR 80-363]), and in the description of location 44 by MacKevett and Holloway (1977).
Geology: This occurrence is immediately east of the Twin Hills lode (MM168), in the contact zone of the McGonagall granitic pluton mapped by Reed (1961, plate 1). The deposit consists of replacement veins and disseminations of magnetite in a zone estimated to be 20 to 30 feet wide (Moffit, 1933, p. 324). A small amount of chalcopyrite occurs with the magnetite, and the rocks locally are ironstained and coated with copper carbonate(?). Sphalerite occurs in a fracture zone about 100 yards north of the magnetite deposit. The deposit probably is middle Tertiary, the approximate age of the emplacement of the Eocene or Oligocene McGonagall pluton (Reed and Lanphere, 1974). The occurence is one of several in a belt of mineral deposits along the north flank of the McGonagall pluton.
Workings: The deposit was discovered by W. J. Shannon in about 1930.
Age: The deposit probably is middle Tertiary, the approximate age of the emplacement of the Eocene or Oligocene McGonagall pluton (Reed and Lanphere, 1974; Cole, 1998).
Alteration: Oxidation of iron and copper minerals.

Commodities (Major) - Fe; (Minor) - Cu, Zn
Development Status: No
Deposit Model: Disseminated and vein-form, polymetallic lodes and contact deposits (Cox and Si

Other Databases

Link to USGS - Alaska:	MM163

Other Regions, Features and Areas containing this locality

References