|Quadrangle map, 1:250,000-scale||CR|
|Quadrangle map, 1:63,360-scale||A-1|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Alameda or Tomboy prospect is southeast of Kitkun Bay at an elevation of about 300 feet. It is about 1.0 mile north-northwest of hill 2221 and near the center of the NE1/4 section 27, T. 77 S., R. 88 E.|
Geologic descriptionAs described by Brooks (1902) as part of the Tomboy Group, this deposit is a series of quartz veins that form topographic knolls and were reported by the owner to have been traced for about 3,000 feet. The veins are bounded on one side by marble and on the other by chlorite schist. Most of the quartz appears to be barren; some contains pyrite. Wright and Wright (1908) note that one of the claims was restaked as the Alameda, and describe the deposit as a quartz vein about 4 feet wide that strikes north and dips 50E. The vein has low gold values. The rocks in the area are part of the Wales Group of Late Proterozoic and Cambrian age (Eberlein and others, 1983; Brew, 1996). No workings are reported.
|Geologic map unit||(-132.130093876485, 55.1681444357713)|
|Mineral deposit model||Low sulfide, gold-quartz vein (Cox and Singer, 1986; model 36a).|
|Mineral deposit model number||36a|
|Age of mineralization||Younger than the Late Proterozoic or Cambrian host rocks.|
|Workings or exploration||No workings are reported.|
|Indication of production||None|
Brew, D.A., 1996, Geologic map of the Craig, Dixon Entrance, and parts of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-2319, 53 p., 1 sheet, scale 1:250,000.
Brooks, A.H., 1902, Preliminary report on the Ketchikan mining district, Alaska, with an introductory sketch of the geology of southeastern Alaska: U.S. Geological Survey Professional Paper 1, 120 p.
Eberlein, G.D., Churkin, Michael, Jr., Carter, Claire, Berg, H.C., and Ovenshine, A. T., 1983, Geology of the Craig quadrangle, Alaska: U.S. Geological Survey Open-File Report 83-91, 52 p.
|Reporters||D.J. Grybeck (Applied Geology)|
|Last report date||5/1/2004|