|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||The Gullies prospect includes several mineralized exposures on the south side of the Jarvis Glacier in a steep walled canyon about 4 miles east-southeast of the Pleasant Camp border station on the Haines Highway. They are in the NE1/4, section 30, T. 28 S., R. 53 E. The prospect was informally called the 'Jarvis Glacier Gulches' prospect by Still and others (1991); Constantine Metal Resources Ltd. (2008) called it the Gullies prospect.|
Sulfide float found by the U. S. Bureau of Mines at the mouth of a steep north-draining canyon led to the initial discovery of some of the occurrences in August, 1983. Other occurrences were discovered by Alyu Mining Corporation in September, 1983.
According to Still (1984), the occurrences are located in the Little Jarvis volcanic-sedimentary sequence that consists of basalt, andesite, and metasediments and slate and limestone (Redman, 1983). Most of the occurrences are in slate, limestone and andesite, capped by andesite and pillow basalt. The Little Jarvis sequence probably correlate with the Glacier Creek sequence which hosts the Glacier Creek prospect (SK066) (Redman, 1983). They are part of the Late Triassic Hyd Group which hosts similar deposits the length of southeastern Alaska and into Canada(Newberry and others, 1997).
Still (1984) describes a mineralized exposure at an elevation of about 3,600 feet on the southwest side of the canyon (his number 109 on figure 8). The exposure consits of a zone of metasediments and andesite altered to chlorite that contains lenses of massive and disseminated sulfides. The zone follows bedding, is up to 5 feet thick, and contains massive-sulfide lenses up to 0.5 foot thick. It can be traced at least 100 feet. The sulfide lenses consist of pyrite, sphalerite, chalcopyrite, and galena in calcite- and quartz-rich rock. Samples contained up to 17.8 percent zinc, 0.3 percent lead, 1.3 percent copper, 11.56 parts per million (ppm) silver, and 0.163 ppm gold (Still, 1984; Still and others, 1991). On the northeast side of the canyon at an elevation of 3,200 feet are quartz-stringer zones and sulfide zones. Samples of the sulfide zones contained up to 6.1 percent zinc, 0.76 percent copper, 110 ppm cobalt, 4.64 ppm silver, and 0.127 ppm gold (Still, 1984; Still and others, 1991).
Greig and Giroux (2010) note that this mineralization may be the northwest extension of the important RW and South Wall mineralized horizons at the Glacier Creek prospect (SK066) about 3 miles to the southeast. Their map (figure 5 ) also shows that these mineral occurrences extend northwest for about 3 kilometers to the Little Jarvis Glacier and ARDF site SK069.There have been several published studies of the mineral deposits in the area by government and academe (MacKevett and others, 1974; Still, 1984, Still and others, 1991; Newberry and others, 1997; Greig and Giroux, 2010) and unpublished studies by industry. The consensus from early on was that the they are Late Triassic, stratiform volcanogenic massive-sulfide deposits.
|Geologic map unit||(-136.453566307955, 59.4200620740984)|
|Mineral deposit model||Probably a Kuroko- or Besshi-type volcanogenic massive sulfide system with associated veining (Cox and Singer, 1986; models 28a or 24b).|
|Mineral deposit model number||28a or 24b|
|Age of mineralization||Late Triassic by analogy with the many other similar deposits of that age spread along the length of southeastern Alaska and into Canada.|
|Alteration of deposit||Chloritic.|
|Workings or exploration||Sulfide float found by the U.S. Bureau of Mines lead to the initial discovery of some of these occurrences here in August, 1983. Other occurrences were discovered by Alyu Mining Corporation in September, 1983. The deposit has probably been visited and sampled by several of the succession of companies who have worked in the area. It has not been drilled.|
|Indication of production||None|
Constantine Metal Resources Ltd., 2008, Palmer property info: http://www.constantinemetals.com/projects/palmer/palmer/ (as of April 9, 2008).
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.
Greig, C.J., and Giroux, G.H., 2010, Palmer VMS project, southeast Alaska; Mineral resource estimation and exploration update: Technical l report for Constantine Metal Resources Ltd. 82 p. (posted on www.sedar.com, Mar. 8, 2010).
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.
Newberry, R.J., Crafford, T.C., Newkirk, S.R., Young, L.E., Nelson, S.W., and Duke, N.A., 1997, Volcanogenic massive sulfide deposits of Alaska, in Goldfarb, R.J. and Miller, L. D., eds., Mineral deposits of Alaska: Economic Geology Monograph 9, p. 120-150.
Redman, E.C., 1983, Reconnaissance geology of the Glacier Creek area, Skagway B-4 quadrangle, Alaska, in Appendix B of Still, J.C., 1984, Stratiform massive sulfide deposits in the Mt. Henry Clay area, southeast Alaska: U.S. Bureau of Mines Open-File Report 118-84, 65 p.
Rubicon Minerals, 1998, Palmer VMS Project, southeast Alaska, Executive Summary: Unpublished report by Rubicon Minerals Corporation, Vancouver, British Columbia, 25 p.
Still, J.C., 1984, Stratiform massive sulfide deposits in the Mt. Henry Clay area, southeast Alaska: U.S. Bureau of Mines Open-File Report 118-84, 65 p.
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., Gilbert, W.G., and Forbes, R.B., 1987, Final report of stream sediment, float, and bedrock sampling in the Porcupine mining area, southeast Alaska, 1983-1985: U.S. Bureau of Mines Open-File Report 36-87, 35 p., 8 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); D.J. Grybeck (Contractor, USGS)|
|Last report date||2/28/2011|