GEOLOGICAL SURVEY CIRCULAR 219 RECONNAISSANCE OF URANIUM AND COPPER DEPOSITS IN PARTS OF NEW MEXICO, COLORADO, UTAH IDAHO, AND WYOMING By Garland B. Gott and Ralph L. Erickson UNITED STATES DEPARTMENT OF THE INTERIOR Oscar L. Chapman, Secretary GEOLOGICAL SURVEY W. E. Wrather, Director GEOLOGICAL SURVEY CIRCULAR 219 RECONNAISSANCE OF URANIUM AND COPPER DEPOSITS IN PARTS OF NEW MEXICO, COLORADO, UTAH, IDAHO, AND WYOMING By Garland B. Gott and Ralph L Erickson Thia report COilC8l'D8 work doDe oa behalf of tbe U. S. Atomic Enerp Commiaion and is publiahed with the~ of the Commiuion Waahiqton, D. C1 196t Free on applieation to the Geolocical Survey, Wllhiqton 26, D. C. RECONNAISSANCE OF URANIUM AND COPPER DEPOSITS IN PARTS OF NEW MEXICO, COLORADO, UTAH, IDAHO, AND WYOMING CONTENTS Page Page Abstract ....... ·............•.•.............. 1 The copper and uranium deposits--Continued Introduction .........••..................... 1 Colorado--Continued Acknowledgments ............................ 2 The Cashin mine . 4 The copper and uraniurr, deposits ............. 2 Utah ........................•........ 5 New Mexico ............................ 2 The Big Indian mine .......•........ 5 Cuba, Abiquiu, and Gallina districts.... 2 Torrey district . • . • . 5 Jemez Springs district. .............. 4 The San Rafael Swell district. .. 5 Zuni Mountain and Scholle districts .... 4 Source of the uranium in the Pintada-Pastura district. ............ 4 asphaltites . 7 Tecolote district . 4 Idaho .................................. 8 Guadalupita district. ................ 4 Wyoming .............................. g San Acacia district .................. 4 Conclusions . 9 Colorado ............................... 4 Literature cited .. ~· . .. 9 ILLUSTRATION Page • Figure 1. Some copper and uranium deposits in parts of New Mexico, Colorado, Utah, and Wyoming........ ~ TABLES Page Tabl'e 1. Radiometric and chemical analyses of samples from some uranium and copper deposits in sandstone ........................................................................... 10 2. Spectrographic analyses of some crude oils, asphalts, and carbonaceous shales ................ 16 ABSTRACT The similarity of the metal assemblage in the San Rafael Swell asphaJ.tites to the metal assemblage in Because of the common association of uranium crude oil and other bituminous materials suggests that and copper in several of the commercial uranium these metals were concentrated in the asphaltites from deposits in the Colorado Plateau province, a recon­ petroleum. However, it is possible that uranium naissance study was made of. several known deposits minerals were already present before the hydrocarbons of copper disseminated through sandstone to determine were introduced and that some kind of replacement of whether they might be a source of uranium. In order uranium minerals by carbon compounds was effected to obtain additional information regarding the relation­ after the petroleum migrated into the uranium deposit. ship between copper, uranium, and carbonaceous mate­ rials, some of the uraniferous asphaltite deposits in The widespread association of uranium with the Shinarump conglomerate along the west flank of asphaltic material suggests that it also may have been the San Rafael Swell were also investigated briefly. concentrated by some agency connected with the forma­ tion of petroleum. The problem of the association of Dl.ll"ing th,is reconnaissance 18 deposits were uranium and other trace metals with hydrocarbons examined in New Mexico, 8 in Utah, 2 in Idaho, and should be further studied both in the field and in the 1 each in Wyoming and Colorado. laboratory. Commercial grade uranium is not associated INTRODUCTION with the copper deposits that were examined. The uraniferous asphaltites in the Shinarump conglomerate Copper, in varying proportions, is associated of Triassic age on the west flank of the San Rafael with uranium in many of the sandstones on the Colorado Swell, however, are promising sources of commercial Plateau. This association is thought to have resulted uranium. from the deposition of these two metals under similar chemical conditions. To test this theory and to search Spectrographic analyses of crude oil, asphalt, for new sources of uranium, a reconnaissance was made and bituminous shales show a rather consistent ~uite of some of the known.copper deposits in sandstones of of trace metals including vanadium,. uranium, nickel, other areas on and adjacent to·the plateau. copper, cobalt, chromium, lead, zinc, and molybdenum. 1 This reconnaissance was made on behalf of the grains and nodules disseminated through the sandstones, Atomic Energy Commission during the summer of and as fracture fillings. The secondary carbonates 1951 in parts of New Mexico, Colorado, Utah, Idaho, and silicates have been deposited adjacent to the and Wyoming. The results are summarized in this chalcocite, but in some places they cement the sand report. grains where copper sulfides are not present. The location, age of host rock, mineralogy, The most abundant copper minerals in the radioactivity, chemical analyses, and a brief descrip­ deposits are malachite, chalcocite, azurite, and tion of the deposits that were examined are tabulated chrysocolla. Malachite is the most prominent mineral, in table 1. Arbitrary numbers have been assigned to but its bright color and its presence, in some places, each deposit and these numbers refer to the same as a coating or halo around chalcocite grains and deposits m both table 1 and figure 1. The information nodules may result in disproportional estimates of about the deposits in each State is briefly summarized the two minerals. Azurite is present in much smaller below. quantities than malachite but, nevertheless, is widespread. Chrysocolla is most abundant in the ACKNOWLEDGMENTS Copper City and Pintada-Pastura districts in New Mex­ ico. Covellite was identified in about one-third of the The writers wish to express their appreciation deposits. Chalcopyrite, cuprite, copper sulfates, to Charles B. Read of the Geological Survey, for un­ and native copper are sparingly present in a few published maps and reports of many of the deposits deposits. that were examined during this investigation. They are also indebted to various members of the u. s. During a two-day reconnaissance of the San Geological Survey, Denver laboratory, for spectro­ Rafael Swell in Utah, a few of the uraniferous asphaltite graphic, chemical, and radiometric analyses. deposits were briefly examined. The deposits about A. T. Myers, spectr0grapher, and C. A. Horr, chemist, which the writers have obtained information are not who are responsible for the analyses of hydrocarbons, known to be extensive, but a similar deposit at Temple are carrying out investigations concerning the asso­ Mountain, on the southeastern corner of the San Rafael ciation of uranium and other metals with hydrocarbons, Swell, apparently contains comparatively large which will be the subject of a later report. resources of uranium. The asphaltic material occurs as ·rounded grains, stringers, pods, and irregular THE COPPER AND URANIUM DEPOSITS masses in the Shinarump conglomerate. Small quan­ tities of uranium-bearing carbonized w~od are also The deposits examined during this investigation present. The hydrccarbons apparently range from an are in northern New Mexico, southeastern Utah, south­ asphalt largely soluble in carbon disulfide to residual western Colorado, southeastern Idaho, and southwestern asphaltites (or pyrobitumens ?) that are only slightly Wyoming. Within this region post-Cretaceous intrusive soluble in carbon disulfide. The residual asphaltites and extrusive rocks cover large areas and pre-Cambrian contain rr.core uranium and other metals than do the rocks are exposed in many of the major Paleozoic soluble asphalts. orogenic belts. However, late and post-Paleozoic sedimentary rocks, principally of continental origin, Several metals are present in the asphaltites are most abundant. Thousands of feet of varicolored, including Fe, Ti, Co, Cu, Mo, Ni, Pb, U, V, and Zn. but predominantly reddish, aeolian and fluvial sand­ Compounds of these metals are present in the asphaltite­ stones and conglomerates that alternate with lesser bearing rock and include pyrite, arsenopyrite(?), zinc­ amounts of shales, sandy shales, and clays are the nickel-cobalt sulfate, chalcopyrite, bornite, chalcocite, most prominent components of the sedimentary sequence. covellite, malachite, azurite, paraschoepite( ?)1 and The rocks of this sequence range in age from Pennsyl­ metatorbernite. vanian to Recent. Spectrographic analyses of a few asphaltite The copper deposits appear to fit a classification samples from this area show that the metal suite in consisting of two general types: deposits in which the the asphaltites is the same as is present in crude oils. controlling factors of deposition appear to have been This suggests that the metals in the asphaltites may the presence of carbonaceous material and relatively have been concentrated from crude oil by a combination high porosity, and deposits in which the predominant of volatilization, oxidQ.tion, and polymerization re­ controlling factor appears to have been faulting or sulting in a concentration of the metal-bearing asphal­ fracturing. tenes and other heavy hydrocarbons. More extensive investigations to determine the metal compounds and The deposits, for the most part, range in size their relationship to the organic constitu~nts in a from a few cubic inches of