Mineral Resources Southeastern Alaska M.I.R.L
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Mineral resources of southeastern Alaska Item Type Technical Report Authors Wolff, E.N.; Heiner, L.E. Citation Wolff, E.N. and Heiner, L.E., 1971, Mineral resources of southeastern Alaska: University of Alaska Mineral Industry Research Laboratory Report No. 28, 334 p., 12 sheets. Publisher University of Alaska Mineral Industry Research Laboratory Download date 11/10/2021 10:27:19 Link to Item http://hdl.handle.net/11122/1081 MINERAL RESOURCES OF SOUTHEASTERN ALASKA M.I.R.L. Report No. 28 MINERAL INDUSTRY RESEARCH LABORATORY University of Alaska College, Alaska Ernest N . Wol ff Lawrence E. Heiner November, 1 971 TABLE OF CONTENTS Page ACKNOWLEDGMENTS i LlST OF FIGURES LlST OF TABLES LlST OF PLATES INTRODUCTION LOCATIO N BRIEF HISTORY CLIMATE PLANTS AND ANIMALS SETTLEMENTS, COMMUNICATION AND TRANSPORTATION GEOGRAPHY AND PHYSIOGRAPHY REGIONAL GEOLOGY OF THE CORDILLERA Introduction Stratigraphic Sequences and Orogenies of the Cordillera Purcell Sequence Windermere Sequence Sauk Sequence Cariboo Orogeny Cache Creek Sequence Cassiar Orogeny Hazelton-Takla Sequence Coast Range Orogeny K-rss Sequence Rocky Mountain Oregony, Late Cretaceous and Paleocene Tertiary Deposition Puget Orogeny THE TECTONIC BELTS OF THE NORTHWEST CORDILLERA DISTRIBUTION OF MINERAL DEPOSITS IN BRITISH COLUMBIA RELATION OF MINERAL DEPOSITS TO TECTONIC BELTS Page REGIONAL GEOLOGY OF SOUTHEASTERN ALASKA GENERALIZED GEOLOGIC HISTORY IGNEOUS lNTRUS I0 NS Distribution and Composition Chronology of Intrusion CORRELATION, GEOLOGY AND ORE DEPOSITS PRODUCT10 N OF MINERALS IN SOUTHEASTERN ALASKA Gold copper Silver - Lead - Zinc Tungsten Uranium Barite Totals Admiralty District Chichagof District Hyder District Juneau District Juneau Subdistrict Skagway Subdistrict Glacier Bay Subdistrict Ketchikan District Wales Subdistrict Ketchikan Subdistrict Kupreanof District Petersburg District Petersburg Subdistrict Wrangell Subdistrict Yakutat District Page TABULATION OF MINERAL DEPOSITS 64 INFORMATION RECORDED FOR MINERAL OCCURRENCES 197 COMPUTER PRl NTOUT 0 F MINERAL PROPERTY REFERENCE FILE FOR SOUTHEASTERN ALASKA REFERENCES CITED BIBLIOGRAPHY ACKNOWLEDGEMENTS Much of this report is based upon records of the Alaska Division of Geological Survey. Mr. James A. Williams of that Division was of great help in making the records available, A special thanks goes to Dr. Earl H. Beistline, Dean of the College of Earth Sciences and Mineral lndustry here at the University of Alaska. He helped with many of the problems that arose during the research. Thanks also goes to Mr. Gordon Herreid of the Alaska Division of Geological Survey for his many useful suggestions. The following people also contributed to this report: Mr. Larry Shafford, Miss Judy Burleson, Mr. Jerry Colp, Miss Carol Murray, Mr. William R. Sothen and Mr. Rod Blakestad. Finally Dr. Nils I. Johansen of the Mineral Industry Research Laboratory has been most helpful with ~roblemsof editing and compilation. LIST OF FIGURES Page Figure I. Locat ion map. 2 Figure 2. U. S. Bureau of Mines Mining Regions and Districts and U. S. Geological Survey Quadrangles. Figure 3. Map showing locations of settlements in Southeastern Alaska . Figure 4. Metal content related to sequences in British Columbia (after McKechnie, 1966, p. 201). Figure 5. Tonnages of ore from stratigraphic sequences in British Columbia (after McKechnie, 1966, p. 201). Figure 6. Percentages of occurrences of Gold by stratigraphic and igneous sequence. Figure 7. Percentages of occurrences of Copper by stratigraphic and igneoys sequence. Figure 8. Percentages of occurrences of Lead by stratigraphic and igneous sequence. Figure 9. Percentages of occurrences of Molybdenum by stratigraphic and igneous sequence. Figure 10. Percentages of occurrences of Iron by stratigraphic and igneous sequence. Figure 11 . Percentages of occurrences of Nickel by stratigraphic and igneous sequence. Figure 12. Locations of mining areas, Southeastern Alaska. LlST OF TABLES Page Table 1, Distribution of deposits with age. 18 Table 2. Distribution of deposits in rock sequences. 19 Table 3. Mineralization in the belts. 20 Table 4, Relative importance of metals in the belts. 2 1 Table 5. Correlation chart, British Columbia and Southeastern Alaska 28 sequences and events. LlST OF PLATES (in pocket) Plate 1. Geological map of Southeastern Alaska, obtained through the cooperation of the Canadian Institute of Mines and Metallurgy (from C. I.M. Spec. Vol. 8). Plate 2. Ail prospects, including non-metallics. Plate 3. Metallic prospects. Plate 4. Copper prospects Plate 5. Gold prospects. Plate 6, Lead prospects . Plate 7. Molybdenum prospects Plate 8, Iron prospects. Plate 9. Nickel prospects, Plate 10, Currently active prospects. Plate 11 . Major Linears . Plate 12. Major tectonic features, This report is part of a series by the Mineral Industry Research Laboratory describing the mineral occurrences of Alaska. Thus far reports have been issued on Northern Alaska (No. 16) Seward Peninsula (No. 18) and the Wrangell Mountain - Prince William Sound areas (No. 27). All of these reports contain tabulations of all deposits described in the literature. Report No, 27 also has computer drawn maps showing locations of mineral occurrences and a computer printout of certain data about each property. The magnetic tape which produced this printout was made as part of the project under which the report was written, It is capc~bleof printing several options, as described in M. I.R. L. Report No. 24, The present report, M, I, R. L. Report No. 28, also contains a printout, and is also backed up by a mognetic tape. The location maps contained in the back pocket of this report have already been published in limited edition as M. I.R. L. Report No. 25, because it was desired to disseminate the information contained on them as fast as possible, It is hoped that reports such as this eventually will be issued for all of Alaska. Southeastern Alaska, the "Panhandle" comprises the first Judicial District of Alaska, It is almost completely isolated from the rest of the State, and includes all of Alaska east of the southern extension of the Alaska-Yukon boundary which coincides with longitude 141 (see Figure 1). In the U. S, Bureau of Mines classification it is called the Southeastern Alaska Region, and contains, from south to north, the Hyder, Ketchikan, Kupreanoff, Petersburg, Admiralty, Chichugof, Juneau, and Yakutat Districts, (Figure 2). It is covered by the following 1 :250,000 U.S.G.S. quadrangle maps: Prince Rupert, Dixon Entrance, Ketchikan, Craig, Bradfield Canal, Petersburg, Port Alexander, Sumdum, Sitka, Taku River, Juneau, Mt. Fairweather, Atlin, Skagway, Yakutat, and Mt. St. Elias (see Figure 2 ). a REPORT AREA FIGURE 1. LOCATION MAP BRIEF HISTORY The first white settlements in Alaska, after Kodiak, were established in South- eastern Alaska by the Russians. Before the transfer to the United States, little or no prospecting had been done in Southeastern Alaska, although some small placers were found on the bars of the Stikine River in Canada. About 100 men went to these dig- gings, most of them entering and leaving by the coast. After the transfer, a few Americans went to Sitka, but apparently the lack of a stable government discouraged exploration, although a few men stayed to see what the country had to offer. Much more extensive placers were found in the Gassier District of British Columbia in 1871 and a stampede of several thousand men ensued. The dissemination of many of these men through Southeastern Alaska after the stampede provided the first impetus to mining in the Region and in Alaska. These men in 1874 and 1875 found small placers on the Unuk River and at Windham Bay, In 1871, gold quartz was discovered 15 miles south of Sitka but although ore was extracted and milled for several years, the operation never was a financial success. It was in 1880, however, that the big discovery was made which started Alaska upon an industrial expansion based upon mining. In that year, Joseph Juneau and Richard T. Harris, under a grubstake agreement with Sitka and San Francisco backers, found the gold quartz and placer deposits on Gold Creek and the neighboring Hills at the site of what is now Juneau. During the nexf few years, large scale low grade quartz mining began at the Treadwell Mine on Douglas Island; this continued until 1916 when the sea broke into the workings which had been extended under the chan- nel. In 1886, gold quartz was discovered on Berner's Bay, which did not, however, prove as valuable as that around Juneau. Beach placers of small extent and richness were found at Yabtat Bay in 1887 and at about the same time in Lituya Bay. A similar deposit was found at Yakataga about 1898, and placer gold was also discovered on Porcupine Geek near Haines in 1898. The quartz of Silver Bow Basin and Juneau was mined with indifferent results from the time of its discovery. For about 20 years prior to 1930, attempts were made to mine the deposit on a larger and larger scale. During the 20'5, the output gradually increased and in 1930, the original investment was completely returned. The mine continued as the Alaska-Juneau, until shut down by war in 1943. Copper mineralization on Prince of Wales Island was known even during Russian days and an attempt was made in 1879 to start a copper industry there. However, it was not until the early part of the present century that production started. kom 1905 to about 1919, various copper mines produced on a fairly extensive scale. From 1905 to 1908, there was even a copper smelter in operation at Hadley . Intermittent, small production continued until about the beginning of the second World War. Many smaller lode mines have operated from time to time in Southeastern Alaska. Perhaps the most notable is the Hirst-Chichagof gold mine on Chichagof Island, but the mine has been shut down for many years. Although mining has gradually declined since World War II, a steady exploration effort has been made.