Open-file Report 79-760 Open-file Report 79-760 UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY Mail Stop 954, Federal Center, Box 25046 Denver, Colorado 80225 INVENTORY OF CLAY-RICH BEDROCK AND METAMORPHIC DERIVATIVES IN EASTERN NEVADA, EXCLUDING THE NEVADA TEST SITE Compiled by H. E. Simpson 1 , J. VI. Weir, Jr. 1 , and L. A. Woodward2 iU.S. Geological Survey, Denver, Colo. 2University of New Mexico under contract with Sandia Laboratories, Albuquerque, N. flex. CONTENTS Page Summary 1 Introduction 1 Purpose and scope 1 Procedure 3 Regional setting 6 Future investigations 11 Annotated definitions 13 Conversions and abbreviations 15 Compilation and acknowledgments 15 Clark County 16 CL-1: Spring Mountains locality 17 Elko County 19 EL-1: Independence Mountains locality 20 EL-2: Wild Horse locality 24 EL-3: HD Range locality 27 EL-4: Pilot Range locality 30 EL-5: Spruce Mountain and Pequop Range locality 32 EL-6: Pirion Range locality 35 EL-7: Adobe Range locality 41 Eureka County 44 EU-1: Diamond Mountains locality 45 EU-2: Prospect Ridge locality 48 Lincoln County . 50 LI-1: Southern Egan Range locality 51 LI-2: Southern Schell Creek Ranoe locality 53 LI-3: Dutch John Mountain locality 55 LI-4: Bristol-Highland Ranges locality 57 LI-5: Delamar Mountains locality 61 LI-6: Meadow Valley Mountains locality 65 LI-7: Desert Range locality 68 Nye County, northern part 70 NN-1: Toquima Range locality 71 NN-2: Hot Creek Range locality 74 NN-3: Southern Pancake Range locality 77 NN-4: Southern White Pine Range locality 79 NN-5: White River Valley locality 82 NN-6: Quinn Canyon and Grant Ranges locality 84 Nye County, southern part 87 The Eleana Formation 37 NS-1: Belted Range locality - ~~ 89 ii CONTENTS Continued Page White Pine County 91 WP-1: Ruby Mountains locality 92 WP-2: Cherry Creek Range locality 95 WP-3: Northern Egan Range locality -- _- _ __ 98 WP-4: Northern Schell Creek Range locality -. 102 WP-5: Antelope Range locality -. 107 WP-6: Kern Mountains locality -. no WP-7: Snake Range locality -. 113 WP-8: Southern Schell Creek Range locality -. 116 WP-9: Central Egan Range locality -. 120 WP-10: Jakes Wash locality -.__--_- . 123 WP-11: Northern White Pine Range locality -. 125 WP-12: Pancake Range locality . 128 Reference list 131 ILLUSTRATIONS Page [Plates are in pocket] Plate 1. Map showing localities of exposed clay-rich bedrock in Clark County, Nev. 2. Map showing localities of exposed clay-rich bedrock in Elko County, Nev. 3.--Map showing localities of exposed clay-rich bedrock in Eureka County, Nev. 4.--Map showing localities of exposed clay-rich bedrock in Lincoln County, Nev. 5.--Map showing localities of exposed clay-rich bedrock in northern Nye County, Nev. 6. Map showing localities of exposed clay-rich bedrock in southern Nye County, Nev. 7. Map showing localities of exposed clay-rich bedrock in White Pine County, Nev. Figure l.--Map showing localities in eastern Nevada, excluding the Nevada Test Site, that contain clay-rich bedrock and metamorphic derivatives of such rocks 2 2.--Diagrammatic representation of the principal divisions of geologic time 7 3.--Major surface-drainage basins of Nevada excluding the western one-fourth 10 4. Map showing generalized pattern of ground-water flow in relation to localities containing clay-rich bedrock and metamorphic derivatives 12 5. Stratigraphic cross section showing subum'ts of the Pioche Shale in the Pioche mining district area 60 m TABLES Page Table 1. Alphabetical list of major geologic units and subunits referred to in this report, together with the geological age of each as used by the U.S. Geological Survey and a listing of those localities wherein the unit may be suitable for further investigation 9 2. Measured section of Chainman Shale in the NW 1/4 sec. 18, T. 31 N., R. 53 E., and S 1/2 sec 12, T. 31 N., R. 52 E. 37 3. Stratigraphic section of the Pioche Shale measured on western flank of the Delamar Mountains 63 iv Open-file Report 79-760 Open-file report 79-760 UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY Mail Stop 954, Federal Center, Box 25046 Denver, Colorado 80225 INVENTORY OF CLAY-RICH BEDROCK AND METAMORPHIC DERIVATIVES IN EASTERN NEVADA, EXCLUDING THE NEVADA TEST SITE By H. E. Simpson, J. E. Weir, Jr., and L. A. Woodward Six counties of eastern Nevada contain 36 localities that include areas of exposed clay- rich sedimentary bedrock, slightly to moderately metamorphosed derivatives of such rocks, or both (fig. 1). In each locality one or more of these kinds of rocks constitute one or more geologic units greater than 152 m (500 ft) in thickness and 0.8 km 2 (0.3 mi 2 ) in area at the ground surface. The several kinds of sedimentary and metamorphic rocks considered here, kinds in which nuclear wastes might be stored below the ground surface, are referred to, for the purpose of this report, as "clay-rich rocks." These rocks locally meet or exceed arbitrarily selected minimum conditions of lithology, thickness, and area! extent. These places are grouped into localities and may be deemed suitable for further investigation. The localities identified are in Clark, Elko, Eureka, Lincoln, Nye, and White Pine Counties. The types of clay-rich rocks that might be useful include claystone, siltstone, shale, and various mixtures of them, together with metamorphic derivatives which include argillite, metasiltstone, slate, phyllite, schist, and gneiss. The geologic units that contain such clay-rich rocks also commonly contain mixtures, interlayers, and lenses of sandstone, conglom­ erate, and limestone, and their metamorphic derivatives: quartzite, conglomerite, and marble. Initially, the principal areas in Nevada where clay-rich rocks more than 31 m (100 ft) thick are exposed at the ground surface were identified by searching published geologic liter­ ature. From those areas, localities that contain exposed clay-rich rocks more than 152 m (500 ft) thick and of more than 0.8 km 2 (0.3 mi 2 ) in area were selected. For each locality a brief descriptive text was prepared. Seven factors that might be significant in selecting specific localities best suited for further investigation are summarized therein. The factors are: (1) geographic location, (2) land ownership, (3) accessibility, (4) proximity to popula­ tion concentrations, (5) geologic setting, (6) hydrologic setting, and (7) mineral-resource activity. INTRODUCTION Purpose and Scope The possibility of using rock as a medium for the underground storage or disposal of nuclear waste materials has been recognized for several years (National'Academy of Sciences/ National Research Council, 1957; U.S. Department of Energy/Office of Science and Technology Policy, 1978). Several very different kinds of rock have been suggested for this purpose. Notably these include salt, shale, granite, basalt, and welded tuff, each of which might have one or more useful physical or chemical properties for the purpose. 1 120° 119° 118° 116° 115° 42 -__l_______l_ HUMBOLDT 41° i , I__________ I I PERSHING j / 40°- JCHURCHILL" ~7^ ST CARSON U-*Cv' \ CITY ~~p-,.i_ 39°HKO^ f 'MINERAT~p __I \38 ^*& K r."T^".7\\r '*~~~nY"- !i ^ CLARK CL-I 50 100 MILES \ x ^ KILOMETERS 36° 50 100 n Figure 1. Localities containing exposed clay-rich bedrock and metamorphic derivatives of such rocks in eastern Nevada, excluding the Nevada Test Site, described in this inventory report. Localities are numbered sequentially by counties, and Nye County is arbitrarily divided into two parts. This report contains the results of the first phase of an investigation of the geologic and hydrologic potential for such use of exposed shale in Nevada, other clay-rich rocks, and slightly to well-metamorphosed derivatives of such rocks. The NTS (Nevada Test Site) is excluded from consideration here as comparable studies are being made there by others. This investigation was made by the USGS (U.S. Geological Survey) at the request of the DOE (U.S. Department of Energy). The first phase of this investigation was based mainly on an examination of published geologic and hydrologic literature, as only a few of numerous unpublished theses and disserta­ tions on the area are readily accessible. In many cases, however, the data and conclusions in such unpublished reports are included or summarized by others, perhaps with modification, in the published literature. Nearly all of the published geologic material was prepared by geologists of the Nevada Bureau of Mines and Geology, the USGS and various colleges and universities. A few of the publications were prepared by geologists in commercial enterprise or private consulting practice. Sources of hydrologic data consist predominantly of reconnaissance-series and water-resources reports prepared by USGS personnel for publication by the Nevada Department of Conservation and Natural Resources. Procedure Geologic literature was scanned for information about clay-rich rocks in Nevada. Effort then was concentrated mainly on the eastern part of the State for it was evident from the geologic history, and from the literature scanned, that the finer grained, thicker geologic units are located there. A map compilation was made of those areas in eastern Nevada where clay-rich rocks are known to be exposed and are known to be 31 m (100 ft) or more thick. From this compilation were selected those places where the clay-rich rocks were known to be 152 m (500 ft) thick or more, and the surface exposure is apparently larger than 0.8 km2 (0.3 mi 2 ). These constraints were arbitrarily selected on the following inferences: (1) a minimum unit thickness of nearly 31 m (100 ft) might be required for underground operations as presently contemplated, (2) a minimum unit thickness of 152 m (500 ft) might be needed for any useful properties that clay-rich rocks might possess to be significantly effective in containment of stored nuclear wastes, and (3) a surface area of 0.8 km 2 (0.3 km 2 ) might be the minimum extent required for surface facilities at a storage location.