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Copper Deposits in Sedimentary and Volcanogenic Rocks

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Copper Deposits in Sedimentary and Volcanogenic Rocks GEOLOGICAL SURVEY PROFESSIONAL PAPER 907-C COVER PHOTOGRAPHS 1 . Asbestos ore 8. Aluminum ore, bauxite, Georgia 1 2 3 4 2. Lead ore. Balmat mine, N . Y. 9. Native copper ore, Keweenawan 5 6 3. Chromite-chromium ore, Washington Peninsula, Mich. 4. Zinc ore, Friedensville, Pa. 10. Porphyry molybdenum ore, Colorado 7 8 5. Banded iron-formation, Palmer, 11. Zinc ore, Edwards, N.Y. Mich. 12. Manganese nodules, ocean floor 9 10 6. Ribbon asbestos ore, Quebec, Canada 13. Botryoidal fluorite ore, 11 12 13 14 7. Manganese ore, banded Poncha Springs, Colo. rhodochrosite 14. Tungsten ore, North Carolina Copper Deposits in Sedimentary and Volcanogenic Rocks By ELIZABETH B. TOURTELOT and JAMES D. VINE GEOLOGY AND RESOURCES OF COPPER DEPOSITS GEOLOGICAL SURVEY PROFESSIONAL PAPER 907-C A geologic appraisal of low-temperature copper deposits formed by syngenetic, diagenetic, and epigenetic processes UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1976 UNITED STATES DEPARTMENT OF THE INTERIOR THOMAS S. KLEPPE, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director First printing 1976 Second printing 1976 Library of Congress Cataloging in Publication Data Tourtelot, Elizabeth B. Copper deposits in sedimentary and volcanogenic rocks. (Geology and resources of copper) (Geological Survey Professional Paper 907-C) Bibliography: p. Supt. of Docs. no.: I 19.16:907-C 1. Copper ores. 2. Rocks, Sedimentary. 3. Rocks, Igneous. I. Vine, James David, 1921- joint author. II. Title. III. Series. IV. Series: United States Geological Survey Professional Paper 907-C. TN440.T68 553'.43 76-608039 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 Stock Number 024-001-02791-7 APPRAISAL OF MINERAL RESOURCES Continuing appraisal of the mineral resources of the United States is con­ ducted by the U.S. Geological Survey in accordance with the provisions of the Mining and Minerals Policy Act of 1970 (Public Law 91-631, Dec. 31, 1970). Total resources for purposes of these appraisal estimates in­ clude currently minable resources (reserves) as well as those resources not yet discovered or not currently profitable to mine. The mining of mineral deposits, once discovered, depends on geologic, economic, and technologic factors; however, identification of many deposits yet to be dis­ covered, owing to incomplete knowledge of their distribution in the Earth's crust, depends greatly on geologic availability and man's ingenuity. Consequently, appraisal of mineral resources results in approximations, subject to constant change as known deposits are depleted, new deposits are found, new extractive technology and uses are developed, and new geologic knowledge and theories indi­ cate new areas favorable for exploration. This Professional Paper discusses aspects of the geology of copper as a framework for appraising resources of this commodity in the light of today's tech­ nology, economics, and geologic knowledge. Other Geological Survey publications relating to the appraisal of re­ sources of specific mineral commodities include the following: Professional Paper 820-"United States Mineral Resources" Professional Paper 926-"Geology and Resources of Vanadium Deposits" Professional Paper 933-"Geology and Resources of Fluorine in the United States" Professional Paper 959-"Geology and Resources of Titanium in the United States" CONTENTS Page Page Abstract ........................................................................................... C1 Mesozoic disseminated copper deposits-Continued In traduction .................................................................................... 1 Triassic. .................................................................................... C12 Acknowledgments .................................................................... 1 Connecticut Valley and southeastern Pennsylvania ........ 12 Concepts of genesis .................................................................. 1 Nacimiento, N. Mex ......................................................... 13 Definition of terms .................................................................. 2 Guadalupe County, N. Mex ............................................. 14 Geochemistry ........................................................................... 3 Paleozoic disseminated copper deposits ......................................... 14 Problems of genesis of copper deposits .................................. 3 Permian ......................................................•.............................. 16 Copper deposits forming now ........................................................ 4 Kupferschiefer, from England through Poland ............... 16 Modern bog and lake deposits ................................................ 4 West Ural foreland, U.S.S.R ............................................ 17 Copper from runoff .......................................................... 4 Creta, Okla....................................................................... 17 Copper from ground water .............................................. 4 Garvin County, Okla ....................................................... 18 Deposits from copper-rich brines ............................................ 4 Guadalupe County, N.Mex............................................. 18 Salton Sea ......................................................................... 4 Southern Colorado and northern New Mexico ............... 19 Red Sea ............................................................................. 6 Carboniferous .......................................................................... 19 Cheleken Peninsula .......................................................... 6 Dzhezkazgan, Kazakh S.S.R .............................................. 19 New Britain and the Solomon Islands ............................ 6 Precambrian disseminated copper deposits .................................... 19 Copper deposits related to the present cycle of weathering ... 6 African Copperbelt, Zambia and Zaire .................................... 19 Colorado Plateau .............................................................. 6 Udokan, Siberia ....................................................................... 21 Copper-sulfide deposits related to crustal-plate boundaries .......... 8 Northwestern Montana ............................................................ 21 Plate tectonic theory reviewed ................................................. 8 South Australia ........................................................................ 23 Island-arc environment. ........................................................... 9 White Pine, Mich .................................................................... 23 Divergent-plate-boundary deposits .......................................... 9 Diagenesis and metamorphism affect copper ................................ 24 Cenozoic disseminated copper deposits .......................................... 10 Summary: metallogenic provinces and the copper cycle ............... 26 Tertiary .................................................................................... lO Copper deposits and brines ..................................................... 26 Boleo, Mexico ................................................................... 10 Brines as diagenetic agents ............................................... 26 Corocoro, Bolivia ............................................................. 11 Brines as syngenetic agents .............................................. 27 Mesozoic disseminated copper deposits .......................................... 11 Ground water, copper, and red beds ................................ 27 Jurassic(?) and Triassic(?) ........................................................ 11 Targets for prospecting ........................................................... 28 Wyoming fold belt ........................................................... 11 References cited ............................................................................... 28 ILLUSTRATIONS Page FIGURE l. Map of the world showing major lithospheric plates and Cenozoic disseminated copper deposits......................................... C5 2-4. Photomicrographs 2. Dolomite filling of voids in Nugget Sandstone............................................................................................................. 7 3. Navajo Sandstone cemented by malachite and with remaining pores filled with cuprite and chrysocolla................. 7 4. Spicular limestone from the Kaibab Limestone replaced by chalcedony, malachite, and chrysocolla ........................ 8 5. Diagram of plate tectonic hypothesis and its relation to copper deposits................................................................................. 9 6. Map of the western United States showing areas of stratabound copper deposits in rocks of Mesozoic and Paleozoic ages........................................................................................................................................................................................ 12 7. Photomicrograph of Nugget Sandstone showing chalcopyrite associated with bituminous material..................................... 13 8. Photomicrograph of sulfide replacement of fossil wood from the Chinle Formation.............................................................. 13 9. Photograph of fossil wood replaced by massive chalcocite.......................................................................................................
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