STUDIES RELATED TO WILDERNESS PRIMITIVE AREAS OHIO GEOL06ICM. iUKVtl C/5 C 85' *>j SAWTOOTH, IDAHO f O \ SURVEY BULLETIN 1319-D Mineral Resources of the Sawtooth i Primitive Area, Idaho By THOR H. KILLSGAARD and VAL L. FREEMAN, U.S. GEOLOGICAL SURVEY and by JOSEPH S. COFFMAN, U.S. BUREAU OF MINES STUDIES RELATED TO WILDERNESS-PRIMITIVE AREAS GEOLOGICAL SURVEY BULLETIN 1319-D An evaluation of the mineral potential of the area -tTNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1970 UNITED STATES DEPARTMENT OF THE INTERIOR WALTER J. HICKEL, Secretary GEOLOGICAL SURVEY William T. Pecora, Director Library of Congress catalog-card No. 79-607357 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, B.C. 20402 STUDIES RELATED TO WILDERNESS PRIMITIVE AREAS In accordance with the provisions of the Wilderness Act (Public Law 88-577, September 3, 1964) and the Conference Report on Senate bill 4, 88th Congress, the U.S. Geological Survey and the U.S. Bureau of Mines are making mineral surveys of wilderness and primitive areas. Areas officially designated as "wilderness," "wild," or "canoe," when the act was passed were incor­ porated into the National Wilderness Preservation Sys­ tem. Areas classed as "primitive" were not included in the Wilderness System, but the act provides that each primitive area be studied for its suitability for incor­ poration into the Wilderness System. The mineral sur­ veys constitute one aspect of the suitability studies. This bulletin reports the results of a mineral survey in the Sawtooth Primitive Area and vicinity, Idaho. The area discussed in the report includes the primitive area, as defined, and some bordering areas that may come under discussion when the area is considered for wilderness status. CONTENTS Page Summary _ Dl Introduction ____________-_ _ 3 Previous studies _____________ _ _ 7 Present investigation and acknowledgements _ _ 8 Geology ______ _ _________________ 9 Setting ____________________________________ 9 Thompson Peak Formation ___________ 9 Idaho batholith ______________________________ 10 Granodiorite, quartz monzonite, and quartz diorite 10 Leucocratic (white) quartz monzonite ______ ___ __ 11 Sawtooth batholith _____________________________ 12 Pink granite _____________'._______________________ 12 Challis Volcanics ___________________________ 12 Tertiary dikes __________________________-. __ 13 Tertiary (?) gravel ______________________ _ 15 Quaternary deposits __________________________ 16 Glacial deposits __________.________________ 15 Alluvial deposits __________ 16 Structure __________________________________ 17 Faults _________________________________ 17 Joints _________________________________ 18 Mineral resources appraisal _______________:_________ 18 Setting ____________________________________ 18 Methods of evaluation __________________________ 21 Sampling and analytical techniques _________________ 21 Evaluation of sample data ______________________ 23 Aeromagnetic survey and interpretation ______________._ 26 Mineral commodities ________________:____ _.__ 27 Economic considerations _______________ - _ 27 Molybdenum ________________________________ 28 Beryllium ______________________^_L_____ 30 Niobium _____ _ _ ___ __ ___________ 32 Urariium ________________________________ 32 Gold and silver ___________________________ 37 Lead, zinc, and copper ________________________ 39 Other commodities __________________________ 41 Mining claims _______________________________ 42 Mines, prospects, and mineralized areas _______________ 42 Leggit Creek-La Moyne Creek area _______________ 45 Basin claims __________________________ 45 Pilot Knob prospect ______________________ 48 Vre Non placer ________________________ 49 VI CONTENTS Page Mineral resources appraisal Continued Mines, prospects, and mineralized areas Continued Rock Creek area ___________________________ D50 Lucky group ____ _______________ 50 Crooked Tree group _____________________ 51 Upper Billy Creek _______________________ 54 Little Queens River area _____________ _ 54 Little Queens mine ________________ 55 Ford prospect ___________,.________ - 59 Money prospect __ ____ 59 Barger group ________ 62 Browns Creek prospect ____ _ 64 Money quartz prospect ____________ 65 China Basin _____________________ . 65 Black Warrior Creek area ______________________ 66 Overlook mine _________________________- 69 Mule Creek prospects ______________________ 71 Magnolia Creek prospect ___________________ 72 North Branch Magnolia Creek prospect ___________ 72 Johnson Creek area _________________________ 73 Upper Grouse Creek property ________________ 73 Grouse Creek-Black Warrior Creek ridge ________ 75 Corder group __________________________ 76 Bayhorse Pass prospects ____________________ 79 Johnson Creek prospects ___________________ 81 Other occurrences _______________________ 82 Payette placer area _________________________ 82 Observation Peak area ______________________- 91 Greenback mine _________________________ 91 Stanley Lake Creek ______________________ 96 Trail Creek ___________________________ 96 Silver Creek ___________________________ 98 Alturas Lake Creek area ______________________ 99 Star Mountain prospect ___________________ 99 No. 1 Ole claim ________________________ 100 Section 8 prospect _________________-____- 101 Fault zone deposit _____________________ 101 Alturas Lake Creek-Mattingly Creek divide .area ______ 102 Massive quartz deposit _______________1_____ 102 Alphabet group ______________________ 103 This Is It claim ________________________ 103 Altered zones ________________________ 104 Johnson Creek-Ross Fork area __________________ 104 Gold Run Creek prospect __________________ 104 Gold Run Creek outcrop _ 105 D H D claim __________________________ 105 Glens Peak-Upper Payette River area ______________ 106 Glens Peak prospects _________________ 107 Blue Crystal claims __ _________ 107 Blue Gem claims _ 108 Inama prospect __________________________- 108 CONTENTS VII Page Mineral resources appraisal Continued Mines, prospects, and mineralized areas Continued Glens Peak-Upper Payette River area Continued Pinchot Creek _________________ D109 Other occurrences _________ 109 Cramer Lakes area _____ ___ - 110 Hidden Lake area _______ ___ _ 111 Southern altered zone _______ 111 Northern altered zone _______ 112 Manganese deposit ____ 113 North Fork Boise River area ___________ 114 Ballentyne Creek prospect _____ _ 114 Picket Mountain prospect ____________ 114 Ridge prospects ____________ _ 115 Greylock Mountain-Blizzard Mountain area _________ 116 McDonald Peak area ______________________ 117 Toxaway Lake-Twin Lakes areas _.___________ _ 118 Baron Creek area ___________________ ____ 119 Mount Regan prospect _______________________ 119 Alpine Lake area __________________________ 120 Fishhook Creek area ______._________________ 120 Iron Creek area ___________________________ 121 Goat Creek area __________________________ 121 Bear Creek area ___________________________ 122 Appraisal of findings _____________________________ 123 References ______1____________________________ 125 Index ________________________________________ 173 ILLUSTRATIONS Page PLATE 1. Generalized geologic and magnetic intensity map of the Sawtooth Primitive Area, Idaho ________In pocket 2. Map of the Sawtooth Primitive Area, Idaho, showing sample localities, altered and (or) mineralized areas, and mines or prospects ___________In pocket FIGURE 1. Index map showing location of Sawtooth Primitive Area, Idaho _______________________ D4 2-6. Photographs: 2. Sawtooth Range looking southwest _____ 5 3. Sawtooth Range looking southeast ______ 6 4. Looking southeast arcross Sawtooth Lake toward the headwaters of North Fork of Baron Creek __________________ 7 5. Diabase dike cutting pink granite ______ 14 6. Stanley Lake, looking south __________ 16 VIII CONTENTS Page FIGURE 7. Map showing mines, prospects, areas of altered or = mineralized rocks, and mining areas in the vicinity of the Sawtooth Primitive Area ___L_______ D20 8-12. Maps of the Sawtooth area showing location of sam­ ples containing: 8. 15 ppm or more molybdenum ___^_____ 29 9. 20 ppm or more beryllium .___ ___ 31 10. 100 ppm or more uranium ____________ 33 11. 2 ppm or more silver ________L_________ 38 12. 100 ppm or more lead ______________ 40 13. Map of Basin claims workings, Leggit Creek-Lai Moyne Creek area ______________________ 44 14. Photograph showing prospect bench in massive quartz vein, Basin claims ____________________ 46 15. Map of Crooked Tree No. 2 prospect, Rock Creek area 52 16. Map of surface workings, Little Queens mine ____ 56 17. Photograph of portal and dump of main adit, Little Queens mine ______________________ 58 18. Geologic map of main adit, Little Queens mine ____ 60 19. Photograph of prospect pit in upper part of Little Queens workings _________________'_ _____ 62 20-22. Maps of: 20. Money prospect, Little Queens River area _ 63 21. Mines and prospects in upper part of Black Warrior Creek area _________ 66 22. Main workings, Overlook mine, Black War­ rior Creek area ____________:___ 67 23. Aerial photograph of the Overlook mine _______ 68 24-26. Maps of: 24. Upper Grouse Creek workings, Johnson Creek area ______;___'_____________ 74 25. Corder group workings, Johnson Creek area_ 77 26. Payette-placer area _______________ 83 27. Aerial photograph of the Payette placer area ____ 84 28. Map showing veins and sample localities in the Ob­ servation Peak area __________________ 92 29. Geologic map of main adit, Greenback