|Quadrangle map, 1:250,000-scale||PE|
|Quadrangle map, 1:63,360-scale||B-3|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Location known exactly and easily found; deposit exposed in a rock quarry adjacent to a logging road on central Zarembo Island. Site in the SW1/4, section 27, T. 63 S., R. 80 E. Locality 63 of Grybeck, Berg, and Karl (1984).|
The country rock is a Tertiary alkalic granite well exposed in a rock quarry; the intrusive is cut by spherulitic felsic dikes which are in turn cut by andesite dikes (Brew, 1997 [OF 97-156-E]).The mineralization consists of quartz veinlets and lenses an inch or so thick in an altered shear zone about 4 feet wide that cuts the granite. The quartz vein material contains a few percent of ore minerals including chalcopyrite, bornite, galena, sphalerite, arsenopyrite, and magnetite. Analysis of a selected high-grade grab sample show major Pb, Zn, and Cu consistent with the hand-specimen mineralogy, less than 0.005 ppm Au, up to 50 ppm Ag, up to 15 ppm Sn, and up to 3 ppm W. The exposure of the vein is small but could indicate more vein-type mineralization in the area.
|Geologic map unit||(-132.918714105562, 56.3736518947083)|
|Mineral deposit model||Polymetallic vein along shear zone (Cox and Singer, 1986; model 22c)|
|Mineral deposit model number||22c|
|Age of mineralization||Tertiary or younger.|
|Workings or exploration||Occurrence first found by the USGS in the late 70s in a quarry excavated for road metal. To 1996, no obvious signs or published descriptions of other work at the site.|
|Indication of production||None|
Brew, D.A., 1997, Reconnaissance geologic map of the Petersburg B-3 quadrangle, southeastern Alaska: U.S. Geological Survey Open-File Report 97-156-E, 23 p., 1 sheet, scale 1:63,360.
|Reporters||H.C. Berg (Fullerton, California) and D.J. Grybeck (USGS)|
|Last report date||11/1/1998|