Upper Triassic volcanogenic Zn-Pb-Ag(-Cu-Au) mineral deposits near Petersburg, Alaska

Geologic map of southeastern Alaska

“…Consists of: unnamed rhyolite on Annette lsland and the Puppets Formation (rhyolite) on Gravina lsland (Berg, 1982); the Chapin Peak Formation (basalt) on Gravina lsland (Berg and others, 1978); the Keku Volcanics (rhyolite and subordinate basalt) and the Hound lsland Volcanics (basalt and andesite) in Keku Strait (Muffler, 1967;Brew and others, 1984); and unnamed basalt near Haines (Plafker and Hudson, 1980;Redman and others, 1984;Robertson, 1959 (Berg and others, 1978); the Nehenta Formation on Gravina lsland (Berg and others, 1978); unnamed strata interpreted to occur as blocks in a disrupted sedimentary unit (KJsd) on Kupreanof and Zarembo lslands (D.A. Brew, in U, S. Geological Survey, 1982;Brew and others, 1984;Berg and Grybeck, 1980); and the part of the Hyd Formation on Admiralty lsland that has been reliably separated from the Cannery Formation (Ps) (Lathram and others, 1965 (Berg, 1982), the Cornwallis Limestone and Hamilton lsland Limestone on northern Kuiu and Kuprcanof lslands (Muffler, 1967;Brew and others, 19841, and the Whitestripe Marble on Chichagof lsland (Loney and others, 1975;Johnson and Karl, I 982).…”

“…This unit occurs only on Admiralty lsland and consists of the Barlow Cove Formation (Barker, 1957) and of strata originally mapped by Lathram and others (1965) (MacKevett and others, 1974;Robertson, 1959;Redman, 1984b) that are of mid to late Paleozoic and probable Triassic age (Berg and Grybeck, 1980;Redman, 1984b). These rocks herein are interpreted to be correlative with sedimentary and volcanic rocks of Permian, Devonian, and Silurian age in Glacier Bay (Brew and others, 1978) and in the Chilkat Range (Lathram and others, 19591, and Triassic to Ordovician strata that adjoin rocks in this unit along the British Columbia-Alaska border north of Glacier Bay (Campbell and Dodds, 1983).…”

Significant metalliferous lode deposits and placer districts of Alaska

“…SOURCES: Dunbier and others, 1979;Drechsler and Dunbier, 1981;J. Dunbi er and D. Sherkenbach, written commun., 1984;Henry C. Berg, written commun., 1984 Buddington, 1923;Henry C. Berg, oral commun., 1984;Grybeck and others, 1984 Buddington, 1923;Berg and Grybeck, 1980;Grybeck and others, 1984 Howard, 1935;Gault, 1945;Donald Grybeck and David A. Brew, written commu n. , 1985 Thompson and others, 1982;Lancelot and de Saint-Andre, 1982;Armstrong, 1985;Edward M. MacKevett, Jr., written commun., 1986;J.…”

Significant metalliferous and selected non-metalliferous lode deposits and placer districts for the Russian Far East, Alaska, and the Canadian Cordillera

“…Dunbier and others, 1979;Drechsler and Dunbier, 1981;J. Dunbier and D. Sherkenbach, written commun., 1984;Henry C. Berg, written commun., 1984;Newberry, Brew, and Crawford, 1990;Brew and others, 1991;Wells and others, 1986; Reed and Coats, 1941;Still and Weir, 1981;Johnson and others, 1982;Bundtzen, Green, Deager, and Daniels, 1987;Brew and others, 1991 and Grybeck, 1980;Grybeck and others, 1984;Brew and others, 1991. Schroeter, 1987;Northern Miner, August 31,1987;Metis and Clifford, 1987;Osatenko and Britton, 1987;Dawson and others, 1991 Fine-grained sphalerite, galena, chalcopyrite as disseminations, and in massive layers and lenses associated with metamorphosed Paleozoic and lower Mesozoic mafic pillow flows, highly altered and metamorphosed quartz-feldspar porphyry, thin phyllitic siltstone and limestone. Sparse disseminated pyrite, magnetite, and tetrahedrite.…”