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Significant Metalliferous Lode Deposits and Placer Districts of Alaska

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Significant Metalliferous Lode Deposits and Placer Districts of Alaska By WARREN J. NOKLEBERG, THOMAS K. BUNDTZEN, HENRY C. BERG, DAVID A. BREW, DONALD GRYBECK, MARK S. ROBINSON, THOMAS E. SMITH, and WARREN YEEND U.S. GEOLOGICAL SURVEY BULLETIN 1786 DEPARTMENT OF THE INTERIOR DONALD PAUL HODEL, Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1987 For sale by the Books and Open-File Reports Section U.S. Geological Survey Federal Center, Box 25425 Denver, CO 80225 Library of Congress Cataloging-in-PublicationData Significant metalliferous lode deposits and placer districts of Alaska. U.S. Geological Survey Bulletin 1786 Bibliography Supt. of Docs. No.: 1 19.3:1786 1. Placer deposits-Alaska. 2. Ore deposits-Alaska. I. Nokleberg, Warren J. II. Series. QE75.B9 No. 1786 557.3 s 87-600165 [TN24.A4] [553'.13'09798] COVER Mill buildings at Kennecott, Alaska. The Kennecott district Cu-Ag mines in the Wrangell Mountains were some of the principal sources of copper in North America from 1913 to 1938. See deposit description for Kennecott district (number 30 for southern Alaska). Copyrighted drawing used by permission of Gail Niebrugge, artist, Glennallen, Alaska. PREFACE This report is a compilation of the signifi- geology. The unpublished data were contributed cant metalliferous lode deposits and placer by mineral deposit and regional geologists in districts of Alaska, and is a comprehensive data private industry, universities, the U.S. Geo- base for a companion article on the metallogene- logical Survey, the Alaska Division of Geologi- sis and major mineral deposits of Alaska that cal and Geophysical Surveys, the U.S. Bureau of will be published in the volume on Alaskan Mines, and the authors. Data were also obtained geology for the Decade of North American Geology for classification of metalliferous mineral (DNAG) by the Geological Society of America. deposits from mineral deposit geologists in the This report is based on recent unpublished data U.S. Geological Survey. The 54 contributors who on metalliferous mineral deposits of Alaska. and gave freely of their data, with affiliations at on recent and older published articles and sum- the time of contribution. are: maries of Alaskan mineral deposits and regional Gary L. Andersen, Resource Associates of Alaska, Inc., Fairbanks, Alaska Roger P. Ashley, U.S. Geological Survey, Menlo Park, California James C. Barker, U.S. Bureau of Mines, Fairbanks, Alaska Joseph A. Briskey, U.S. Geological Survey, Menlo Park, California Wi11 iam P. Brosge, U.S. Geological Survey, Menlo Park, California P. Jeffery Burton, Jeffery Burton and Associates, Fairbanks, Alaska Robert M. Chapman, U. S. Geological Survey, Menlo Park, Cal ifornia Edward R. Chipp, Resource Associates of Alaska, Inc., Fairbanks, Alaska Dennis P. Cox, U.S. Geological Survey, Menlo Park, California Robert L. Detterman, U.S. Geological Survey, Menlo Park, California John T. Dillon, Alaska Division of Geological and Geophysical Surveys, Fairbanks, Alaska J. Dunbier, Noranda Exploration, Inc., Anchorage, Alaska Inyo F. Ellersieck - U.S. Geological Survey, Menlo Park, California Jeffrey Y. Foley, U.S. Bureau of Mines, Fairbanks, Alaska Peter F. Folger, Department of Geology, University of Montana, Missoula, Montana Helen L. Foster, U.S. Geological Survey, Menlo Park, California Curtis J. Freeman, The FE Company, Inc., Fairbanks, Alaska D. R. Gaard, Resource Associates of Alaska, Inc., Fairbanks, Alaska Bruce M. Gamble, U.S. Geological Survey, Anchorage, Alaska Wyatt G. Gilbert, Alaska Division of Geological and Geophysical Surveys, Juneau, Alaska Charles C. Hawley, Hawley Resource Group, Inc., Anchorage, Alaska Murray W. Hitzman, Chevron Resources Company, San Francisco, California Brian K. Jones, Bear Creek Mining, Kennecott Corporation, Anchorage, Alaska Ian M. Lange, Department of Geology, University of Montana, Missoula, Montana Christopher D. Maars, Anaconda Minerals Company, Anchorage, Alaska Edward M. MacKevett, Jr., 1230 Bayview Heights, Los Osos, Cal ifornia W. David Menzie, U.S. Geological Survey, Menlo Park, California Paul A. Metz, Mineral Industries Research Laboratory, University of Alaska, Fairbanks, Alaska J. S. Modene, Cominco Alaska, Inc., Anchorage, Alaska David W. Moore, Cominco Alaska, Inc., Anchorage, Alaska William Morgan, Duval Corporation, Anchorage, Alaska Clint R. Nauman, Research Associates of Alaska, Inc., Fairbanks, A1 aska Steven W. Nelson, U.S. Geological Survey, Anchorage, Alaska Rainer J. Newberry, Geology/Geophysics Program, University of Alaska, Fairbanks, Alaska Steven R. Newkirk, Research Associates of Alaska, Inc., Fairbanks, Alaska Harold Noyes, Doyon, Limited. Fairbanks, Alaska Wi11 iam W. Patton, Jr., U.S. Geological Survey, Menlo Park, California Joseph T. Plahuta. Comi nco Alaska, Inc., Anchorage, Alaska Christopher C. Puchner, Anaconda Minerals Company, Anchorage, Alaska John Reed, Hawley Resource Group, Inc., Anchorage, Alaska Donald H. Richter, U.S. Geological Survey, Denver, Colorado Robert K. Rogers, WGM, Inc., Anchorage, Alaska Charles M. Rubin, Anaconda Minerals Company, Denver, Colorado D. A. Scherkenbach, Noranda Exploration, Inc., Anchorage, Alaska Jeanine M. Schmidt, U.S. Geological Survey, Anchorage, Alaska P. R. Smith, U.S. Borax and Chemical Corporation, Spokane, Washington Carl I. Steefel, Anaconda Minerals Company, Anchorage, Alaska J. E. Stephens, U.S. Borax and Chemical Corporation, Spokane, Washington Richard C. Swainbank, Geoprize, Limited, Anchorage, Alaska Gregory Thurow, U. S. Bureau of Mines, Fairbanks, Alaska Alison B. Till, U.S. Geological Survey, Anchorage, Alaska J. Dean Warner, U.S. Bureau of Mines, Fairbanks, Alaska Frederic H. Wilson, U.S. Geological Survey, Anchorage, Alaska Loren E. Young, Corninco Alaska, Inc., Anchorage, Alaska CONTENTS Preface 111 Introduction 1 Acknowledgments 1 Classification of mineral deposits 2 Lode deposit types 2 Placer deposits 6 Explanation of tabular headings 7 Lode deposits 7 Placer 'stricts 8 Abbreviations 8 Conversion factors 8 Significant rnetalliferous lode deposits, Brooks Range 9 Significant rnetalliferous lode deposits, Seward Peninsula 18 Significant rnetalliferous lode deposits, west-central Alaska 23 Significant rnetalliferous lode deposits, east-central Alaska 32 Significant rnetalliferous lode deposits, Aleutian Islands and Alaska Peninsula 41 Signlicant metalliferous lode deposits, southern Alaska 47 Significant rnetalliferous lode deposits, southeastern Alaska 59 Significant placer districts of Alaska 73 References 83 Indexes to rnetallierous lode deposits and placer districts 97 PLATES [In pocket] 1. Map showing locations of significant rnetalliferous lode deposits of Alaska. 2. Map showing locations of significant rnetallierous placer districts of Alaska. Contents V Significant Metalliferous Lode Deposits and Placer Districts of Alaska By Warren J. Nokleberg, Thomas K. Bundtzen.' Henry C. Berg: David A. Brew, Donald Grybeck, Mark S. Robinson, Thomas E. smith,' and Warren Yeend INTRODUCTION as a1 1 metal 1iferous mines, prospects, deposits, or occurrences that the authors and contributors Alaska is commonly regarded as one of the judged to be important, on the basis of size, new frontiers in North America for discovering geological importance, or interest, for an in- metalliferous mineral deposits. A major theme in depth survey. For each deposit, the report also the history of the State has been repeated states for each deposit a precise location, ''rushes'' or "stampedes" to sites of newly dis- common names, major metals or commodities, a covered metalliferous lode or placer deposits. mineral deposit type, the host-rock geology, During the last two decades, there has been data on tonnage, grade, and production, if extensive exploration for lode and placer known, and sources of information. The location mineral deposits by private mining exploration of metalliferous lode deposits is shown on plate companies. During the same period, because of 1; the location of placer districts is shown on the considerable interest in Federal lands in plate 2. Alaska, and the establishment of new national parks, wildlife refuges, and Native corporations, substantial studies of mineral deposits and of the mineral resource potential This report is the result of efforts of the of Alaska have been conducted by the U.S. Geological Society of America to pub1 ish a Geological Survey, the U.S. Bureau of Mines, and series of volumes for the Decade of North Ameri- the Alaska Division of Geological and can Geology (DNAG) on the geology of North Amer- Geophysical Surveys. These studies have resulted ica. We thank George Plafker and David L. Jones, in abundant new information on Alaskan mineral the editors of the volume on Alaskan Geology, deposits. In the same period. substantial for their encouragement. We thank Donald A. geologic mapping has been completed with the Singer and Frederic H. Wilson for their reviews. advent of modern logistical and technical tools. Dennis P. Cox greatly assisted in classification One result of the bedrock studies has been the of mineral deposits. recognition of numerous fault-bounded packages designated as tectonostratigraphic terranes, PREVIOUS STUDIES each with a distinctive stratigraphy, structure, metamorphism, and suite(s) of mineral deposits. Within the last 23 years, a few statewide Proponents of this concept suggest that most of summari es and several regional summaries of Alaska consists of a collage of tectono- Alaskan metalliferous lode
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