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By Francis E. Federspiel

In 1984 and 1985, at the request of the U.S. Forest Service, the U.S. Bureau of Mines examined the 87,720-acre South Boise Yuba study area (formerly known as RARE II Wilderness Recommended area I-4553) to evaluate mineral resources. The study area and additions are in Blaine, Camas, and Elmore Counties, 10, about 60 mi east of Boise. Granitic rocks of the Cretaceous age Idaho Batholith occupy the western two-thirds of the study area. A Tertiary age granitic complex has intruded, and broken into small blocks, Paleozoic age sedimentary rocks in the eastern third of the study area. Tertiary Challis Volcanics overlie both of these rock types. Principal mineralized structures are gold-and silver-bearing quartz veins and shear zones trending northwest to easterly in the Cretaceous granitic rocks. Copper, lead, and zinc are accessory metals in many mineralized structures.

Jan 1, 1987

By C. F. McCarroll

The effectiveness of an industry?s safety activities can be gaged best by the accident records of that industry. In an effort to gage conditions in the petroleum industry, and with the objective of helping to reduce the number of accidents in it, the Bureau of Mines from time to time has tabulated, analyzed, and published pertinent statistical information3/. These reports have dealt with distribution, causes, and costs and related phases of accidents for various and collective divisions of the petroleum industry in several sections of the country. This type of study aids the personnel of the Bureau in planning the course of its activities in accident-prevention work and gives useful data to persons engaged or interested in the promotion of safety in the petroleum industry, which will aid them in their efforts to reduce the number and severity of accidents. A majority of petroleum operators and ?service" contractors have acknowledged their responsibility to provide their employees with safe working conditions and to their stockholders for greater economic value of invested capital by establishing safety divisions within their respective organizations. Such divisions have a primary duty, namely, to see that properly designed and guarded machinery and working equipment are furnished the employees and that they are trained in the safest practical methods of performing their work. Some companies and individual operators, however, have shown little or

Jan 1, 1939

By J. R. Ross

A reconnaissance for sources of scandium and a metallurgical investigation of recovery methods for byproduct scandium from uranium mill solutions were conducted by the Bureau of Mines. The work on scandium was undertaken to obtain information on domestic resources and to explore and develop recovery procedures in consonance with the Bureau's long-range program for conservation and wise utilization of mineral resources. The element scandium is widely distributed in the earth's crust in trace amounts, but it seldom occurs as an important constituent in any mineral. An exception is thortveitite, (Sc,Y)2 Si207) a rare mineral that contains various amounts of scandium and yttrium and may contain up to 42 percent scandium oxide (SC203). Knowledge of the chemistry of scandium has expanded rapidly in recent years (1, 4, 9)4 but only fragmentary information is available about the metal because it is still largely a laboratory curiosity without established uses (2, 3). A recent study shows some of the physical proper-ties of the metal are (1) density of 3.05 grams per cubic centimeter) (2) melting point of 1,540° C, (3) hexagonal close-packed structure) (4) hardness of about 50 Brinell (500-kilogram load), and (5) an alloy behavior similar to yttrium and rare-earth metals (2). The price of $2,850 a pound for scandium oxide of 99.9 percent purity and $2,700 a pound for oxide of 99 percent purity reflects the scarcity and complex chemistry of the element.

Jan 1, 1962

7253. Arkhangelsky, A. D. Geological Results of the General Magnetometric and Gravimetric Surveys of the U.S.S.R. (in Russian). Internat. Geol. Cong., Rep. of the 17th Sess., Moscow-Leningrad, 1937, vol. 1, Moscow, 1939, pp. 241-250. Geophysical methods have been used in the U.S.S.R. to study geological problems. Such is the case of the general magnetometric and gravimetric surveys made jointly by the Main Physical Observatory, Main Office of Geodesy and Cartography, Institute of Terrestrial Magnetism, and Main Office of Geophysical Prospecting. Some institutions supplied the data, others processed them. Geological interpretation was made by the author. (1) Regional magnetic anomalies in the plains of the U.S.S.R. are traceable to the folded substratum overlain by sedimentary rocks; these anomalies promise to yield data characterizing the substratum in respect to strike and depth. Anomalies in European U.S.S.R. suggest that the pre-Cambrian -substratum of the East European plateau consists of elements of different ages. In the most ancient of them, the main strike of the folding is almost latitudinal; in the younger ones, the folding is oriented in the meridian. (2) The Faye and Bouguer gravity anomalies are caused primarily by differences in the density of rocks composing the upper crust and by unknown processes producing changes of density at depth; these processes are not connected with isosiatic movements. The anomalies in the European and adjoining Asiatic U.S.S.R. promise to indicate the volume of the pre-Cambrian massif of the east-European plateau and to clarify the interrelations between the Ural, Tian-Shan, and Donetz Basin folding systems, as well as between the Dnieper-Donetz depression and the mid-European depression. - V. S.

Jan 1, 1944

By Terry R. Neumann

This document, prepared for the U.S. Bureau of Mines Regional Mineral Assessment Program, presents data pertinent to the mineral resource assessment of the Needles 1° x 2° map quadrangle (excluding the Arizona portion), located in the Mojave Desert southeastern California. The U.S. Bureau of Mines (USBM) mineral survey of the quadrangle, conducted from 1991 to 1993, was done to provide the minerals data necessary to support effective land use planning and resource decision making. To this end, this report (1) inventories historic and current mining activity, (2) inventories identified resources, (3) provides an economic analysis; of identified mineral resources and estimates their feasibility for development, (4) delineates areas of exploration and development potential based on current geological, geochemical, and geophysical information, (5) supplies information on land status, transportation networks, power supplies, water availability, and regulations, and (6) analyzes socio-economic impacts of potential mining. The Needles quadrangle is in the Basin and Range province of the southwestern United Van. The area is underlain by a lithologically and structurally complex Proterozoic crystalline basement of gneiss and granite that is overlain by sparse, scattered outcrops of deformed and metamorphosed Late Proterozoic and Paleozoic sedimentary sequences. Mesozoic granitic plutons, particularly in the western half of the quadrangle, intruded the basement and sedimentary rocks, resulting in metamorphism and deformation responsible for the formation of high-grade gneisses and mylonitic rocks (core complex) in the eastern part of the quadrangle. Voluminous Tertiary volcanism unconformably overlie some older sequences. The structure of the area is dominated by Basin and Range extensional block faulting; in the eastern part of the area, block faulting is accompanied by widespread low-angle detachment faulting associated with core complex development.

Jan 1, 1993

By Richard A. Busch

Inadequate engineering design criteria for coal refuse embankments has allowed hazardous impoundment structures in coal mining areas to be created. A necessary first step to develop adequate design criteria is the determina¬tion of basic, respresentative physical property data on the materials that constitute typical refuse embankments. An extensive field and laboratory program was undertaken by the Federal Bureau of Mines. Much physical property data was generated. Additonal petrographic analysis and large scale triaxial compression testing was performed by others. The data presented here should aid in establishing design parameters for coal refuse embankments

Jan 1, 1974

By Carl Sunderman, Steve Signer

Researchers at the National Institute for Occupational Safety and Health (NIOSH) have developed several new tools for evaluating roof support performance. A miniature data acquisition system (MIDAS) was developed that can collect readings from up to 16 strain gauges at regular time intervals and store the readings for later retrieval. Three LED lights change from green to yellow, then red, based on the reading levels and/or rates of change of rock movement. This feature can be used to warn miners of rock instabilities. The system can be used with any strain-gauged support (resin bolt, friction bolt, cable bolt) or with a newly developed rock strain strip (ROSS) developed by NIOSH to measure rock strain. A ROSS is grouted in a hole drilled adjacent to the rock support to be evaluated; the deformed shape of the ROSS provides anchorage on either side of the strain gauges. Data from both laboratory tests and field evaluations are presented that describe the capabilities of both the MIDAS and ROSS instruments.

By Victor E. Kral

The Valery fluorspar deposit , also known as the Hamilton deposit , is northeast of Lovelock and 4 miles by poor dirt road east of U. S. Highway 40 . It is in the Humboldt Mining District , on the west side of the Humboldt Range , at an altitude of 6,000 to 6,500 feet . The property was examined by the Bureau of Mines on February 83/ and April 8 , 1944.4/ The last examination was made with an engineer of the Geological Survey.5/ Exploring by means of trenches , cuts , shaft sinking , coyote holes off the shaft , and a small amount of prospecting with short drill holes , was begun in January 1945 and was completed June 30 , 1945. An engineer6/ of the Geological Survey visited the property in April and again in June 1945 to complete a topographic map of the area and to note the results of exploration by the Bureau of Mines . Only minor surface exploring had been done on fluorspar occurrences previous to the Bureau's work . No mining equipment or living facilities are on the property .

Feb 1, 1947

By John P. Shubilla1, Nicholas Kyriazi

A joint effort by the Pittsburgh Research Center (PRC) and the Mine Safety and Health Administration (MSHA)3was undertaken to determine how well self-contained self-rescuers (SCSR's), deployed in accordance with Federal regulations (30 CFR 75.1714), held up in the underground environment with regard to both physical damage and aging. This report presents findings regarding laboratory-tested SCSR's in the fifth phase of testing from mid-1993to early 1996. The SCSR's were tested on human subjects and on a breathing and metabolic simulator (BMS) at PRC. These results indicate that most of the apparatus, if they pass their inspection criteria, perform satisfactorily.

Jan 4, 1996

By A. C. Smith

The U.S. Bureau of Mines constructed a large-scaJe facility to study the self-heating of a large coal mass under conditions that simulate a gob area of a mine. The insulated coal chamber can hold up to 13 short tons (st) of coal and is provided with a forced ventilation system and computer-controlled temperature and gas measurement systems to monitor the heat and mass transfer phenomena that occur in the coalbed. Three experiments were completed with high-volatile C bituminous coals that exhibited high spontaneous combustion potentials in laboratory-scale tests. In the first two tests, a sustained heating was not achieved. In the third test, temperatures throughout the coalbed increased steadily from the start, with thermal runaway occurring near the center of the coalbed after 23 days. The thermal reaction wne then moved toward the front of the coalbed. The results of these tests showed that the self-heating of a large coal mass depends not just on the reactivity of the coal, but also on the particle size of the coal, the freshness of the coal surfaces, the heat-of-wetting effect, and the availability of O2 at optimum ventilation rates.

Jan 1, 1991

By Michael D. Balen

The Bureau of Mines (Bureau), in cooperation with the Alaska Division of Geological and Geophysical Surveys (ADGGS), conducted field investigations from 1987 through 1989 in the 5.7 million-acre Valdez Creek Mining District (VCMD) in south-central Alaska. The objective of the VCMD investigation was to evaluate the mineral resources and the mineral development potential of the mining district. The investigation was part of the Bureau's continuing statewide mining district evaluation program. Nineteen new mineral occurrences were identified as a result of this investigation. Reconnaissance placer sampling resulted in the identification of 10 previously unreported occurrences that primarily contain gold, however, some contain subsidiary platinum-group metals and/or tin. Reconnaissance lode sampling resulted in the identification of two gold-silver occurrences, three platinum-group metal occurrences that contain elevated quantities of subsidiary chromium, nickel and/or cobalt, three copper occurrences that contain subsidiary molybdenum or zinc, and one zinc occurrence.

Jan 1, 2011

By L. W. Brandt

The Bureau of Mines, as part of its mission to effect pollution abatement, conducted research to study various means of dewatering Florida phosphatic clay wastes and reclaiming mined lands. The work was done in cooperation with 10 Florida phosphate companies. During this work, a novel technique to effectively dewater phosphatic clay wastes was developed. The solids contained in the clay waste slurry are slowly compressed by moving wire mesh screens through the system. In a typical application, the screens were moved downward, compressing solids ahead of the screens. The rate of movement of the screens is an important variable in the process. It is believed that the moving screens distort the gel structure of the phosphatic clay system and cause the release of water. Samples of 18 clay wastes, including a high-grade attapulgite from beneficiation plants of the Florida phosphate field, were studied using the method. Typical samples were concentrated from initial solids of 4.7 and 11.9 percent to 16.8 and 25.2 percent, respectively, in 3-1/2 days. The high-grade attapulgite sample was dewatered from 2.7 percent solids to 13 percent solids in the same period.

Jan 1, 1980

By M. G. Zabetakis, T. D. Moore

The use of a partially slotted 6.5-inch-inside-diameter vertical pipe to remove methane from a longwall gob area at a depth of 2,260 feet in the Pocahontas No. 3 coalbed ms investigated. The value of gas removed by such a pipe under free-flow conditions was found to equal the cost of the installation in this case. Approximately 25 percent of the available methane passed through the pipe without the use of an exhauster; an additional 10 percent was removed when an exhauster was employed. The diversion of methane through a vertical slotted pipe to the surface permitted the use of increased mining rates and decreased the ventilation air requirements.

Jan 1, 1972

By J. R. Thoenen

[Before 1914 Germany held virtual monopoly on the world supply of potash for fertilizer purposes. During the world War, potash shipments to the United States ceased, and recourse was had to domestic supplies. High war-time prices stimulated interest n various sources, and domestic production increased rapidly. At the close of the war, resumption of shipments from Germany and other sources reduced prices to below pre-war levels, and, as a result, most of the domestic producers ceased operational.]

Jan 1, 1941

By R. Blickensderfer

Maintaining an adequate supply of minerals and metals to meet national economic and strategic needs is the overall goal of the Bureau of Mines, U.S. Department of the Interior. One method of achieving this goal is to conserve scarce metals by cladding a plentiful base metal, such as iron, with a scarcer metal. To investigate cladding, a vacuum-rolling mill capable of rolling bimetal specimens at temperatures to 1,300° C in a residual gas pressure of 2 x 10-5 torr was established. Metals that were successfully bonded to iron included stainless steels, chromium, nickel, nickel alloys, copper, and several refractory metals including molybdenum and titanium. The effects of the rolling temperature, reduction in thickness, rolling speed, and residual air pressure on bonding strength and bend ductility of the bimetals were determined. Optimum rolling conditions produced bimetals with bond shear strength essentially equal to that of the iron base metal.

Jan 1, 1980

By B. W. Gandrud, A. C. Richardson

"INTRODUCTION The Bankhead mine of the Cane Creek Coal Mining Co. is in the central part of Walker County, Ala., 4 miles south of Jasper. The Mary Lee bed in this part of the State yields a practically free-burning coal which is marketed as a. steam-raising and domestic fuel. As mined, the coal ordinarily contains ash-forming impurities to an extent that makes it necessary to treat the coal by some washing process before it is marketed. At present the Bank-head coal coarser than 3-1/2 inch is hand-picked and the coal finer than 3-1/2 inch is washed in two single-compartment jigsThis paper contains the result of screen-sizing and float-and-sink tests on a representative sample of the run-of-mine coal and the results of tests made to show the amount of coal liberated from impurities by crushing the coarser sizes. .This report is one of a series on the washability of Alabama coals which is being prepared by the U. S. Bureau of Mines and the University of Alabama, with the cooperation of the coal producers of Alabama.SAMPLING AT THE MINE'The Mary Lee bed at Bankhead consists of two benches separated by a rock parting which varies in thickness from place to place in the mine. The top bench has a very uniform thick-nest; throughout the workings and yields about 65.0 per cent of the output. The bottom bench varies greatly in thickness and in nary places becomes too thin to work at a. profit. The sample for the washability study was taken underground at a place which was typical of the mine as a whole. In taking the sample the working face was squared up and a representative section out from each bench. Care was taken to secure a, quantity of coal from each bench proportional to the quantity contributed to the mine output. The rock parting as gobbed in accordance with the usual mining practice. The total sample taken weighed 3 tons."

May 1, 1933

By Russell R. Trengove

The largest potential reserves of manganese in Nevada are in the Pioche district. To date, these large reserves of 10-to l2-percent manganese cannot be upgraded economically. Other large, low-grade deposits, such as the Virgin River and Boulder City deposits in Clark County, cannot be considered immediate sources of manganese. Reserves of the principal manganese deposits in Nevada, based on the most reliable estimates, total about 17 million tons analyzing 7.6 to 13.6 percent manganese. Most of the deposits are of a type that cannot be prospected systematically but have been prospected and developed in the course of productive mining operations. To realize production from low-grade deposits that are amenable to concentration, a ready market must be provided. Thus far, Government stockpiles have been the major outlet for these low-grade ores. Research and experimentation over a period of years have led to development of several processes technologically applicable to these low-grade ore bodies, but their economics is not sufficient to allow competition with imported ores on the open market.

Jan 1, 1959

By D. E. Andrews

The objective of this study was to investigate the environmental effects of slaking of surface mine spoils. To accomplish this, both field and laboratory programs were undertaken, supplemented by a thorough literature search. The field program consisted of drilling the highwall as well as test pitting in recent, two-, five, and ten- year-old spoil piles at four active mining sites in the eastern bituminous coal fields. Pertinent observations were made and samples collected for laboratory analyses which consisted of several standard geotechnical, agronomic, and geochemical tests. Durability tests utilized included jar slake, cyclic wet-dry, rate of slake, and slake durability tests. Correlation between field and laboratory portions was made- and results presented. The report is concluded with a discussion of the slaking process and associated environmental impacts, proposal of a preliminary classification system for use in premine planning, and presentation of management techniques to optimize the slaking process.

Jan 1, 1980

[Determine how subsidence resulting from underground coal mining affects surface structures, and evaluate the usefulness s of the tiltmeter for monitoring foundation movement. Approach The Bureau of Mines is studying foundation response to mine subsidence in order to determine how subsidence-induced ground movements affect foundations in place directly above the mint. These investigations are essential if economic mitigation and repair techniques are to be made. In addition, commercially available tiltmeter are being evaluated (or use as a cost-effective monitoring technique. To study foundation response and to evaluate the tiltmeter system, full-scale model foundations were constructed, instrumented, and monitored for three years. Vertical and horizontal displacements, tilt magnitudes and directions, and observed damages were recorded. Displacements were compared with measured lilt to determine if the tiltmeter was tracking foundation response to subsidence, The Bureau developed a computer software package to aid in the reduction and analysis of the tiltmeter data.]

Jan 1, 1988

By Fred E. Fiedler

A demonstration project investigated the feasibility and effectiveness of two management interventions, Management Training and Organization Development, for improving productivity and safety in metal/non-metal mines. The management training intervention was conducted at Texasgulf Company's trona mine, using three nearby trona mines as controls. The Organization Development intervention took place in Hecla Mining Company's Lucky Friday mine, using the highly similar Star Mine as control. The two management interventions seemed about equally effective in reducing accidents and injuries, as well as MSHA citations, and the management intervention at the Texasgulf mine also appeared to have led to substantial improvement in mine productivity.

Jan 1, 1983