|Quadrangle map, 1:250,000-scale||SK|
|Quadrangle map, 1:63,360-scale||B-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is at an elevation of 4,500 feet on the north slopes of Flower Mountain, approximately 1.3 miles, N39E from the summit. It is in the NE1/4, section 8, T. 29 S., R. 54 E. of the Copper River Meridian. It is shown as location M by Gilbert and Redman (1989) and number 16 on sheet 1 by Still and others (1991).|
Geologic descriptionAccording to Still and others (1991), the Shannon prospect is a small iron-stained lens of grossularite garnet-sulfide-magnetite skarn discovered in 1987 by Merrill Palmer . Selected high-grade samples from this lens contained up to 0.068 ppm gold, 1.3 ppm silver, 600 ppm zinc, 3,400 ppm copper, and 245 ppm cobalt (Gilbert and others, 1991). The host rocks for this prospect are Paleozoic to early Mesozoic mafic volcanics and sediments near an apophysis of Cretaceous quartz diorite to granodiorite that extends to the northeast from Flower Mountain (MacKevett and others, 1974). The skarn and mineralization are probably related to this intrusive body, thus are probably Cretaceous.
|Geologic map unit||(-136.351864251027, 59.3696636660915)|
|Mineral deposit model||Copper skarn (Cox and Singer, 1986; model 18b).|
|Mineral deposit model number||18b|
|Age of mineralization||Probably Cretaceous based on the age of the nearby intrusive rocks (MacKevett and others, 1974).|
|Alteration of deposit||Skarn.|
|Indication of production||None|
Gilbert, W.G., and Redman, E.C., 1989, Lode deposits, prospects, and occurrences of the Porcupine mining area, southeast Alaska: U.S. Bureau of Mines Open-File Report 17-89, 1 sheet, scale 1:39,600.
Gilbert, W.G., Still, J.C., Burns, L.E., Wier, K.R., and Redman, E.C., 1991, Geochemistry of Haines-Klukwan-Porcupine area, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 91-5, 75 p., 2 sheets, scale 1:63,360.
MacKevett, E.M., Jr., Robertson, E.C., and Winkler, G.R., 1974, Geology of the Skagway B-3 and B-4 quadrangles, southern Alaska: U.S. Geological Survey Professional Paper 832, 33 p., 1 plate.
Still, J.C., 1991, Section A: Haines - Klukwan - Porcupine subarea, in U.S. Bureau of Mines, Mineral investigations in the Juneau Mining District, Alaska, 1984-1988: Volume 2 - Detailed mine, prospect, and mineral occurrence descriptions: U.S. Bureau of Mines Special Publication VOL. 2A, 214 p., 9 sheets.
Still, J.C., Hoekzema, R.B., Bundtzen, T.K., Gilbert, W.G., Wier, K.R., Burns, L.E., and Fechner, S.A., 1991, Economic geology of Haines-Klukwan-Porcupine area, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 91-4, 156 p., 5 sheets, scale 1:63,360.
|Reporters||T.C. Crafford (T. Crafford & Associates, Anchorage)|
|Last report date||2/4/2001|