Unnamed Occurrence (ARDF - JU005; west side of Casement Glacier), Glacier Bay Mining District, Juneau Mining District, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - JU005; west side of Casement 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 1,000 feet, approximately 3 miles west of Snow Dome and 7 miles north of Adams Inlet. It is on a nunatak on the west side of lower Casement Glacier in the NE1/4 section 36, T.33 S., R.56 E. of the Copper River Meridian. The location is accurate.
Geology: This occurrence consists of an iron-stained altered zone that is exposed on a small nunatak of thin-bedded limestone, argillite, and hornfels. The altered zone is about 30 feet thick and contains several quartz-ankerite-barite veins that are less than 1 foot thick. The veins and the altered zone strike N 58 W and dip vertically. Pyrite is the only visible sulfide mineral in either the veins or the altered zone. A select sample contained 300 ppm zinc (MacKevett and others, 1971). The 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). The rocks immediately west of this occurrence are metamorphosed Silurian and Devonian graywacke and argillite that have been intruded by foliated Cretaceous granitic rocks (Brew and others, 1978).
Workings: Only limited surface sampling.
Alteration: Iron staining is reported (MacKevett and others, 1971).

Commodities (Major) - Zn; (Minor) - Ba
Development Status: No
Deposit Model: Possible polymetallic replacement deposit (Cox and Singer, 1986; model 19a)

Other Databases

Link to USGS - Alaska:	JU005

Other Regions, Features and Areas containing this locality

References