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Mineral Resources of the Arc Dome Wilderness Recommendation Area, Nye County, Nevada

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Mineral Resources of the Arc Dome Wilderness Recommendation Area, Nye County, Nevada Mineral Resources of the Arc Dome Wilderness Recommendation Area, Nye County, Nevada Mineral Resources of the Arc Dome Wilderness Recommendation Area, Nye County, Nevada By GERALD F. BREM, DAVID A. JOHN, J. THOMAS NASH, FORREST G. POOLE, and DAVID B. SNYDER An evaluation of the mineral resource potential of the area U.S. GEOLOGICAL SURVEY BULLETIN 1961 STUDIES RELATED TO WILDERNESS­ WILDERNESS RECOMMENDATION AREAS U.S. DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government Text and illustrations edited by Mary Lou Callas Graphics prepared by Diana L. Mangan UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON: 1991 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-Publication Data Mineral resources of the Arc Dome Wilderness Recommendation Area, Nye County, Nevada I by Gerald F. Brem ... [et al.]. p. em. - (Studies related to wilderness-wilderness recommendation areas) (U.S. Geological Survey bulletin ; 1961) Includes bibliographical references. Supt. of Docs. no. : I 19.3:1961 1. Mines and mineral resources-Nevada-Arc Dome Wilderness. 2. Arc Dome Wilderness (Nev.) I. Brem, G.F. (Gerald F.) II. Series. Ill. Series: U.S. Geological Survey bulletin : 1961. QE75.89 no. 1961 557.3 s-dc20 90--24535 [TN24.N3] [553'.09793'34] CIP STUDIES RELATED TO WILDERNESS United States Forest Service Wilderness Recommendation Area Under the provisions of the Wilderness Act (Public Law 88-577, September 3, 1964) and related acts, the U.S. Geological Survey and the U.S. Bureau of Mines have been conducting mineral surveys of wilderness and primitive areas. Studies of all primitive areas have been completed. Areas officially designated as "wilderness," "wild," or "canoe" when the act was passed were incorporated into the National Wilderness Preservation System, and some of them have been studied. The act provided that areas under consideration for wilderness designation should be studied for suitability for incorporation into the Wilderness System. The mineral surveys constitute one aspect of the suitability studies. The act directs that the results of each survey are to be made available to the public and be submitted to the President and the Congress. This report discusses the results of a mineral survey of the Arc Dome Wilderness Recommendation Area (4-667), Toiyabe National Forest, Nye County, Nevada. The area was classified as a proposed wilderness during the Second Roadless Area Review and Evaluation (RARE II) by the Forest Service, January 1979. The Nevada Wilderness Protection Act of 1989 (S. 974) set aside 115,000 acres as the Arc Dome Wilderness, much of which is within the study area. CONTENTS Summary 1 Abstract 1 Character and setting 1 Mineral and energy resource potential 3 Introduction 3 Area description 5 Previous and present investigations 5 Geologic setting 6 Appraisal of identified resources 6 History and production 6 Mineral and energy occurrences 7 Tungsten skarns 7 Polymetallic veins 7 Placer gold and silver 9 Energy resources 9 Industrial minerals 9 Assessment of mineral and energy resource potential 9 Geology 9 Late Proterozoic and Paleozoic rocks 9 Late Proterozoic to Silurian parautochthonous rocks 9 Lower Cambrian allochthonous rocks 9 Pennsylvanian and Permian parautochthonous rocks 10 Mississippian allochthonous rocks 10 Cretaceous and (or) older felsite 10 Mesozoic granitic rocks 10 Cretaceous and (or) Tertiary intrusive rocks 10 Oligocene and lower Miocene volcanic rocks 10 Tertiary and (or) Quaternary rocks 11 Structural geology 11 Geochemical studies 11 Methods 11 Results and interpretation 12 Geophysical studies 13 Aeromagnetic data 13 Gravity data 13 Mineral and energy resources 14 Tungsten skarns 14 Polymetallic veins 14 Placer gold and silver deposits 16 Energy resources 16 Industrial minerals 16 References cited 17 Appendixes 19 Definition of levels of mineral resource potential and certainty of assessment 20 Geologic time chart 21 Contents V PLATE [In pocket] 1. Mineral resource potential and generalized geologic map of the Arc Dome Wilderness Recommendation Area, Nye County, Nevada FIGURES 1. Index map showing location of Arc Dome Wilderness Recommendation Area and Arc Dome Wilderness, Nye County, Nevada 2 2. Map showing mineral resource potential and generalized rock types of Arc Dome Wilderness Recommendation Area, Nye County, Nevada 4 VI Contents Mineral Resources of the Arc Dome Wilderness Recommendation Area, Nye County, Nevada By Gerald F. Brem, David A. John, J. Thomas Nash, Forrest G. Poole, and David B. Snyder SUMMARY is cut by less deeply incised drainages and perennial streams that drop nearly 5,000 ft to the Reese Valley. Abstract Highly deformed Late Proterozoic (presumedly) to Per­ mian (see Geologic time chart in "Appendixes") marine The Arc Dome Wilderness Recommendation Area (4- clastic and carbonate rocks and volcanic rocks underlie 667) encompasses 94,000 acres (the study area) of the much of the study area. These rocks and unconformably southern Toiyabe Range in northwestern Nye County west of Round Mountain, Nevada. The Nevada Wilderness Pro­ overlying Mesozoic silicified and altered tuffs were in­ tection Act of 1 989 (S. 97 4) set aside 1 1 5,000 acres as the truded by Jurassic, Cretaceous, and (or) Tertiary granit­ Arc Dome Wilderness, much of which is within the study oid dikes and stocks. Oligocene and Miocene silicic ash­ area. At the request of the U.S. Forest Service, geological, flow tuffs and other intermediate to silicic lava flows geochemical, and mineral surveys to assess the mineral re­ unconformably overlie all older rocks. Basalt of Tertiary source potential of the study area were conducted by the and (or) Quaternary age and Quaternary surficial depos­ U.S. Geological Survey between 1982 and 1 985; results of its are found in local areas within the mountains. The studies completed in 1971 and 1981 have also been uti­ Toiyabe Range presently stands above alluvium-filled lized. These studies indicate that one part of the study area valleys because of relative uplift along late Tertiary and has high mineral resource potential for tungsten and two (or) Quaternary basin-and-range faults. areas have high potential for silver and (or) gold resources. Several other areas have moderate or low resource poten­ Mining activity has been intermittent in the south­ tial for silver and (or) gold with or without base metals ern Toiyabe Range since 1863 or 1864 when silver-lead­ (lead, zinc, copper, arsenic, and (or) antimony) or for zinc ore was discovered (Kleinhampl and Ziony, 1984). placer gold. The study area has no resource potential for All recorded production has been from mines outside the geothermal energy or for oil and gas. Areas having re­ study area. Prior to 1890, production of silver and lead source potential for tungsten, gold, silver, base metals, and from the Murphy mine north of the study area (fig. 1) geothermal energy outside but near the study area are also exceeded $755,000. Several tungsten mines east of the shown and discussed. Murphy mine and north of the study area produced an estimated $500,000 worth of tungsten between 1950 and 1982. The Last Chance mine south of the study area pro­ Character and Setting duced more than 192 tons of antimony metal between 1915 and 1959. Nine mines or prospects within the study The Arc Dome Wilderness Recommendation Area area produced unknown but presumably small amounts includes the most rugged part of the southern Toiyabe of gold, silver, lead, zinc, copper, and antimony from the Range west of Round Mountain, Nev. (fig. 1). The pre­ 1860's to the 1950's. Most of them were one- or two­ cipitous eastern flank of the Toiyabe Range rises more man operations that have no written records of produc­ than 5,500 feet from the floor of Big Smoky Valley and tion, but some were operated for many years. Many is cut by deeply incised drainages having spectacular mines, claims, prospects, and mineralized areas were cliffs and perennial streams. The moderate western slope recognized within or adjacent to the study area, and 40 are shown on plate 1. Current mining activity within and adjacent to the study area is limited to prospecting and Manuscript approved for publication, October 22, 1990. annual assessment work. Summary AREA OF MAP APPROXIMATE BOUNDARY OF ~ ARC DOME WILDERNESS RECOMMENDATION AREA i (4-{567) ~ Black. ihrrough Mountain Hot/ Spring~ ::r:~ ~f/ (/.) ::r:0 v~/ ~ (/.) "i~· J 0~ &'~ \ " /.~ l "· (jD· L -~~~ro<t-.;;: .. f!./,...... ( Ledbetter .._. ~ \ Canyon 38° ' Ledbetter 45' \ C~yon ) mme ~ ~{ ~ ~) I I >.I ~I ~I \ r/ __fjll ] \ APPROXIMA ~~BOUNDARY } ARC DOME WILDERNESS I I J 0 I I / I -1 I 1 L------------.TOIYABE I I I I ) I I L--....NfiTIO~AL ______FQREST_j : r--------""L---- 1 TOIYABE NATIONAL 0 5 MILES .. :/ I I FOREST I Figure 1. Index map showing location of Arc Dome Wilderness Recommendation Area (heavy line) and subsequent Arc Dome Wilderness (shaded area), Nye County, Nevada. 2 Mineral Resources of the Arc Dome Wilderness Recommendation Area, Nye County, Nevada Mineral and Energy Resource Potential Although a broad area on the west side of the study area has stream-sediment geochemical anomalies suggestive Three types of metallic mineral occurrences have of polymetallic mineralization, the rocks upstream are been recognized in the Arc Dome Wilderness Recom­ not recognizably altered or mineralized; thus, the area is mendation Area: (1) tungsten-bearing skarns; (2) polyme­ assigned only low resource potential for polymetallic tallic veins and disseminated minerals including silver, minerals in or below Tertiary rocks. The southeast cor­ gold, lead, zinc, copper, arsenic, and (or) antimony; and ner of the study area has low resource potential for sil­ (3) placer gold and silver.
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