Unnamed Occurrence (ARDF - JU056; near White Glacier), Glacier Bay Mining District, Juneau Mining District, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - JU056; near White Glacier)	- not defined -
Glacier Bay Mining District	- not defined -
Juneau Mining District	Mining District
Alaska	State
USA	Country

Location: This occurrence is at an elevation of about 2,400 feet, approximately 2 miles east of Mt. Case and 1 mile north of the White Glacier. It is in the SW1/4 section 21, T. 35S., R. 57 E. of the Copper River Meridian. This occurrence is close to location J006 of Wells and others (1986). The location is accurate within 1/4 mile.
Geology: The general area is underlain by deformed and metamorphosed Silurian or Devonian carbonate, clastic and volcanic clastic rocks that have been intruded by Upper Jurassic and Lower Cretaceous granitic and dioritic rocks (Brew and others, 1992). Brew and others (1978) map the country rocks at this occurrence as Permian, thin-bedded limestone and argillite, basalt and andesite, and cherty limestone and siltstone. The deposit is in cherty limestone and consists of an iron-stained zone about 8 feet thick that contains pyrite, chalcopyrite, sphalerite, native silver, native gold, ankerite, barite, celestite, strontianite, and witherite. The deposit is truncated to the south by a mafic dike and is lost under surficial material to the north (Brew and others, 1978). Samples of this zone near a volcanic contact contained up to 4.5 percent zinc, 1,900 ppm copper, 7 ppm silver, 5,000 ppm barium and 500 ppm antimony (Still, 1989). Still (1989) interprets the deposit as a stratabound volcanogenic deposit.
Alteration: Conspicuous iron-staining.

Commodities (Major) - Ag, Au, Ba, Cu, Sr
Development Status: None
Deposit Model: Possible metamorphosed Kuroko massive sulfide deposit (Cox and Singer, 1986; mo

Other Databases

Link to USGS - Alaska:	JU056

Other Regions, Features and Areas containing this locality

References