DEPARTMENT OF THE INTERIOR FRANKLIN K. LANE, Secretary UNITED STATES GEOLOGICAL SURVEY GEORGE OTIS SMITH, Director' Bulletin 648 NOTES ON SOME MINING DISTRICTS IN EASTERN NEVADA BY JAMES M. HILL WASHINGTON GOVERNMENT PRINTING OFFICE 1916 ADDITIONAL COPIES OF THIS PUBLICATION MAY BE PROCURED FROM THE SUPERINTENDENT OF DOCUMENTS GOVERNMENT PRINTING OFFICE WASHINGTON, D. C. AT 20 CENTS PER COPY CONTENTS. Page. Preface, by F. L. Ransome................................................. 15 Field work and acknowledgments........................................... 17 Itinerary................................................................. 17 Previous descriptions..................................................... 19 The region as a whole..................................................... 21 Topography........................................................... 21 Kanges........................................................... 21 Valleys........................................................... 22 Geology.............................................................. 23 Features of geologic structure....................................... 23 Sedimentary rocks................................................. 23 Cambrian.................................................... 24 Ordovician.................................................... 25 Devonian.................................................... 26 Carboniferous................................................. 26 Tertiary...................................................... 27 Quaternary.................................................... 27 Igneous rocks..................................................... 28 Pre-Cambrian rocks........................................... 28 Intrusive rocks................................................ 28 Quartz monzonite......................................... 28 Granite porphyry.......................................... 29 Muscovite granite.......................................... 30 Biotite granite............................................. 30 Other intrusive rocks....................................... 30 Age of the intrusions...................................... 31 Extrusive rocks............................................... 32 Distribution.............................................. 32 Age....................................................... 33 Ore deposits.......................................................... 33 Location and character............................................ 33 Deposits in sedimentary rocks....................................... 34 Replacements................................................. 34 Contact-metamorphic deposits.................................. 35 Veins........................................................ 36 Deposits in granular igneous rocks................................... 37 Veins........................................................ 37 Gold veins............................................... 37 Tungsten veins. J......................................... 38 Disseminated deposits......................................... 38 Deposit in biotite rhyolite tuff..................................... 38 Minerals in the ore deposits........................................ 39 3 4 CONTENTS. Page. Deposits and mines...................................................... 42 Clark County.......................................................'.. 42 Gold Butte mining district........................................ 42 Location and accessibility...................................... 42 Topography................................................... 43 Geology...................................................... 44 Pre-Cambrian rocks........................................ 44 Paleozoic rocks........................................... 45 Quaternary deposits....................................... 46 Basalt................................................... 47 . Structure.................................................... 47 Ore deposits. ................................................. 48 History and production.................................... 48 Character and occurrence of the ores........................ 48 Deposits in limestone..................................... 49 Tramp Miner property................................ 49 Gudice claims........................................ 49 Lincoln mine........................................ 49 Bennett mine.......................................... 50 Bonnella properties................................... 51 Deposits in granite and gneiss............................. 52 Gold Butte Mining Co................................. 52 New Era group................... '. .................... 52 Winona group......................................... 53 Big Thing tunnel..................................... 53 Finance group....................................... 53 v Other prospects...................................... 53 Elko County.......................................................... 54 Order oi description............................................... 54 Ruby Range...................................................... 54 Location and general features.................................. 54 Topography and drainage..................................... 55 Geology...................................................... 55 Age of certain rocks....................................... 55 Sedimentary rocks.............. '. .......................... 56 Igneous rocks............................................. 58 Ore deposits.................................................. 59 Location.................................................. 59 History.................................................. 59 Types of deposits.......................................... 59 Warm Creek district...................................... 60 PolarStar............................................. 60 Other prospects...................................... 60 Ruby Valley (Smith Creek) district......................... 60 Location and features of the deposits................... 60 Friday group......................................... 61 Short group........................................... 61 Valley View district....................................... 62 Hankins property......../.....................-....- 62 Mud Springs district............................................... 64 Location and accessibility...................................... 64 Geology............................................ '. ......... 64 CONTENTS. 5 Deposits and mines Continued. Elko County Continued. Mud Springs district Continued. Page. Ore deposits.........................T........................ 64 History and development..................... ............ 64 Character of the deposits........... % ....................... 65 Deadhorse property....................................... 65 Other prospects. ......................................... 65 Delker district.................................................... 66 Location...................................................... 66 Geology...................................................... 66 Ore deposits.................................................. 66 History and economic conditions........................... 66 Types of deposits.......................................... 67 Spruce Mountain district........................................... 67 Location and accessibility...................................... 67 Topography................................................... 67 Geology...................................................... 68 Sedimentary rocks......................................... 68 Igneous rocks............................................. 68 Contact metamorphism................................... 70 Structure................................................ 70 Mineral deposits.............................................. 71 History and production.................................... 71 Occurrence of the deposits................................. 72 Theores.................................................. 72 The properties........................................... 72 Badger tunnel........................................ 72 Banner Hill claims.................................... 73 Bingle claim......................................... 73 Black Forest claim................................... 73 Copper Queen mine.................................. 74 Fourth of July mine.................................. 74 Keystone mine....................................... 75 Killie (Latham) mine................................. 75 Monarch claim........................................ 76 Never Sweat prospect................................. 76 Spence claims.......................................... 76 Tramp shaft.......................................... 76 Dolly Varden (Mizpah) district..................................... 76 Location and accessibility...................................... 76 Topography................................................... 77 Geology...................................................... 78 Dominant types of rock................................... 78 Sedimentary rocks......................................... 78 Intrusive igneous rocks..................................... 78 Extrusive igneous rocks......:............................ 80 Mineral deposits.............................................. 80 History and production.................................... 80 Character of deposits....................................... 81 Deposits