Report issued by the U.S. Bureau of Mines on the drilling for copper deposits near Pinal County, Arizona in 1949. Topographic and geologic mapping, drilling, and field tests were studied. Tables, maps, and illustrations are presented.

Report issued by the Bureau of Mines over tungsten deposits of Arizona. Characteristics of the tungsten deposits are discussed. This report includes tables, maps, and illustrations.

A report about the economic geology of four mines located in the Helvetia mining district in the Santa Rita Mountains in south central Arizona. The sedimentary rocks in Helvetia range from Cambrain to Cretaceous.

From introduction: A reconnaissance of Arizona uranium deposits was started in October 1950 and continued through April 1951. A total of six man--months was spent by H. C. Granger, E. P. Kaiser, and J. W. Adams. About 40 properties were examined and, of these, six were mapped by plane-table method and six were sketch-mapped. This reconnaissance was not intended as a complete evaluation of all Arizona deposits; other areas and occurrences were not examined during the investigations and are not discussed in this report.

From abstract: During part of February and March 1953, reconnaissance examinations for radioactive material were made at 12 localities in the Yuma Air Force Base gunnery range in southern Yuma County, Ariz. The Yuma gunnery range, which is adjacent to the west edge of the Luke and Williams Air Force Bases gunnery range, is characterized by block faulted, elongate mountain ranges composed essentially of schist, gneiss, and granite of pre-Cambrian to Mesozoic age and separated by broad alluvial basins.

Abstract: About 2,000 tons of low-grade lead ore has been produced from the Jim Kane mine, near Kingman, Mohave County, Ariz. A 3-foot vein of gouge and siderite stringers in pre-Cambrian gneiss contains some lead and, locally, is abnormally radioactive. A sample of the vein contained 0.067 percent uranium. Abnormal radioactivity is restricted to a small part of the vein, and no reserves are calculated.

From abstract: A radioactivity survey of the Black Rock district in southern Yavapai County, Ariz, disclosed anomalous radioactivity in several localities, chiefly at the Abe Lincoln mine in sec. 11, T. 8 N., R. 3 W., about 14 road miles northeast of Wickenburg. The Abe Lincoln vein system occupies a fault zone which strikes N. 500 E. and dips from 780 to 870 NW. Moderate radioactivity is present at the Bracken property and at several other localities in the Black Rock district. The writers recommend re-opening the Abe Lincoln mine to permit a more extensive examination of the vein.

Abstract: Reconnaissance mapping in the Ruby Quadrangle, Arizona, indicates the existence of a complex assemblage of volcanic rocks and associated sediments, divisible into a younger and older series.

Abstract: Field and laboratory study of primary sedimentary features of the Salt Wash sandstone was undertaken to learn if these structures can be of use in finding hidden deposits of ore and also if they have influenced the localization of either individual ore deposits or larger mineralized districts.

From to the files: The Shinarump-Moenkopi contact on Oljetoh Mesa in the Monument Valley district, Arizona-Utah, was examined from November 5 to 15, 1951, to determine the location of and the mineralization in Shinarump channels. Twenty-seven distinct channel outcrops were located and examined. Three of these channel outcrops are mineralized and the remaining 24 are barren. Plate I shows the distribution of the Shinarump, the Moenkopi, and the DeChelly member of the Cutler formation; the location of the Shinarmp channel outcrops; the channel trend where there is good evidence for such a trend. The Hoskinrnini tongue of the Cutler was mapped with the Moenkopi as it is not a good mappable unit in this area. The three mineralized outcrops are indicated by the letters A, G, and AA while the barren outcrops bear the letters B to F and H to Z.

From to the files: To date, all the mineralization seen in the Monument Valley area in the Shinarump formation has been in scour channels. The mineralized rock occurs at or near the bottom of the channel. On Hoskinnini Mesa, all the channels examined to date contain some mineralized material. Channels observed may in some cases contain copper without apparent uranium mineralization; others definitely exhibit copper-uranium mineralization.

Abstract: Horse Mesa is in the Navajo Indian Reservation directly on the Arizona-New Mexico state line. Uranium-vanadium deposits in the Salt Wash sandstone which caps the Mesa are fairly widespread and small tonngges have been shipped from two mines. The deposits lie 60 to 75 feet above the base of the Salt Wash formation and possibly trend northwest parallel to ore trends on King Tutt Mesa, a mile northeast. Carnotite and vanoxite are the principal ore minerals. About 6,000 feet of wagon drilling is recommended to test two favorable areas. Continued exploration should be governed by results of this first stage drilling.

From introduction: The Monument No. 2 mine is in the Navajo Indian Reservation, Apache County, Arizona, about 20 miles southwest from the San Juan River at Mexican Hat, Utah, and 26 miles southwest from Mexican Water, Arizona. The property has been operated, since its discovery, by Vanadium Corporation of America, which holds a 10-year mining lease, granted through the Interior Department, to 43 acres of ground. History of the discovery of the deposit is vague, but reportedly it was first seen around 1942 by a Navajo who mentioned the occurrence to Harry Goulding, Indian trader, who in turn advised D. W. Viles of Vanadium Corporation of America. Minor portions of the deposit are held by Cato Sells and Harvey Black, Navajos, under mining permits issued by the Navajo Tribal Council. The Sells acreage is being operated by Climax Uranium Corporation.

Abstract: Structure drilling under Contract No. AT(05-l)-120 was begun May 13, 1951, and was suspended June 30, 1951, at Red Rock, Arizona with the completion of 12 holes and 2,390.5 feet of drilling. No mineralization was disclosed in the widely spaced holes. The structure and rock composition was found favorable for a potential drilling area.

Abstract: Reconnaissance of Red Rock Valley was begun on December 10, 1953, and completed on February 11, 1954. The mines in the region were investigated and all exposures of Salt Wash were walked. Paleostream directions and alterations of the sandstones were observed and recorded on a base map. No important new mineralization was discovered-and the area is considered to be of no commercial significance if judged by the outcrops alone. However, a vast amount of Salt Wash lies at slight depth directly to the east of the investigated area.

Purpose: A reconnaissance was conducted during parts of August and September, 1956, of an area about two miles square in the southern Carrizo Mountains where the Permian Cutler formation, including its DeChelly member, and the Triassic Shinarump member of the Chinle formation, are exposed. The purpose was to appraise the uranium potential of the area and to determine the cause of bleaching in the DeChelly. Extensive uranium mineralization in the Salt Wash member of the Morrison formation around the Carrizo Mountaind suggested that the Shinarump, a good producer in other areas on the Colorado Plateau, might be mineralized here as well. Bleaching, as shown in the DeChelly; has proven such a useful guide to uranium at other localities as to merit investigation here.

Abstract: Mine mapping of the tyuyamunite-type deposits In the Salt Wash member of the Jurassic Morrison formation of the Lukachukai Mountains, Apache County, Arizona revealed recognizable spatial relationships between ore mineralization and: fractured areas, sedimentary features, and interstitial carbonate.

From introduction: A subsurface exploration program was undertaken to investigate the concentration of uranium and vanadium in or near the base of the Shinarump member of the Chinle formation in the Flatirons locality, and to develop criteria whereby adjacent unexplored areas could be evaluated as to potential production capacity from study of geological and mineralogical features at the host rook outcrop. An earlier study of the area by C. G. Evensen of the U. S. Atomic Energy Commission had shown that geological conditions favorable to the accumulation of commercial uranium deposits were present in the Flatirons area.

Abstract: Napier Drilling Company of Dallas, Texas drilled 53,998.0 feet for exploration purposes, under Contract No. AT(05-1)-256. This footage was drilled in 508 holes during the period from June 21, 1954 through May 13, 1955.

From introduction: The Bluff-Salt Wash contact was mapped on aerial photographs. Mines and prospects were also plotted on the photos. The mines and prospects were studied and a brief description of the mineralization and its occurrence was written. These field notes, which will be given to Hatfield and party, contain data on the presence of carbon and fossil logs, lithology of the gangue rock, sedimentary structures, etc. Regional structure and evidence for igneous activity were also noted.

Summary and conclusion: More than 4000 feet of Lower Miocene lake sediments were deposited upon a gneissic basement rock, at least locally. The sediments have been gently folded into broad anticlines and synclines and have been cut by high-angle faults with displacements on the order of 100 feet. Both basaltic (?) and acid andesitic lavas have intruded the sediments. A Pleistocene (?) conglomerate unconformably overlies all older exposed rocks. The lake sediments were considered to overlie the adjacent thick series of andesite flows (l). This was not established by a cursory examination. The sediments appeared to be in fault contact with the lavas although the relationship was always obscured by the younger conglomerate or alluvial cover. Since a dike of this acid andesitic composition was observed cutting the sediments, there is a possibility that the lake sediments are older than or contemporaneous with the thick extrusive andesite series.

Abstract: To date uranium deposits have been confined to a thin sandstone in a zone near the contact of the Middle and Lower Members of the Toreva Formation and as a leach in the Lower Sandstone Member. On a large scale the deposits are apparently restricted to zones of tectonic deformation. Locally mineralization is primarily controlled by small intraformational channels and cross bedding, and is usually associated with carbonaceous material and quartzose sand lenses.

Subject: This report presents an investigation of a reportedly large low-grade ore body in the vicinity of Cameron, Arizona.

From abstract: A team consisting of R. A. Lindblom, S. A. Mayer, R. G. Young, W. L. Chenoweth, R. F. Droullard, and I. T. Fisk made a reexamination of the Anderson mine (Uranium Aire) of Interstate Oil and Development located near Wickenberg in Yavapai County, Arizona. The field examination was made from August 22, 1958 to September 2, 1958. This team was formed to resolve differences between company and AEC ore reserve estimates. A cooperative effort in which the company supplied labor, limited additional drilling and both parties were in attendance during the sampling resulted in the collection of additional data. Special attention was given to assessing the in-hole assaying with radiometric equipment by IOD and AEC, evaluation of tonnage factors, moisture content, continuity of ore, and current mapping of stripped and mined areas.