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By Michael D. Fenton

The modest mineral industry of Afghanistan continued to suffer adversely from internal disorders that were essentially the result of the continued presence of elements of the armed forces of the U.S.S.R. Despite press reports near yearend intimating that the Soviets might reduce troop strength in Afghanistan, there were no indications of any significant numeric reductions. Indeed, there were clear demonstrations of heightened military actions along the Afghani-Pakistani border, including bombing raids on settlement sites for Afghanis within the territorial limits of Pakistan, actions hardly demonstrative of conditions indicative of Soviet withdrawal.

Jan 1, 1988

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Jan 1, 2011

By J. S. Hansen

The U.S. Bureau of Mines developed a system for casting unique, slotted steel armor by modifying the conventional expendable pattern casting (EPC) process that is normally used for making aluminum castings. Three innovations were added to the EPC process to make the successful adaptation: (1) Vacuum was applied to sand molds, (2) continuous narrow-necked feeding systems were used to permit the casting of thin walls, and (3) fixtures were designed to prevent pattern damage and to hold critical casting tolerances, Potential problems and defects are described.

Jan 1, 2010

By J. Douglas Causey

In 1984, at the request of the Bureau of Land Management, the Bureau of Mines studied 29,020 acres of the 43,165-acre Terry Badlands Wilderness Study Area (MT-024-684) in order to evaluate its mineral resources. Within this report, these 29,020 acres are referred to as the study area. Located in Custer and Prairie Counties, MT, the study area is about 2 miles northwest of Terry. The study area is underlain by essentially flat-lying units of the Fort Union Formation of Paleocene age with some Quaternary alluvial deposits in stream valleys. No mines or prospects were found in the study area. Bentonitic clays and lignite coal units were examined and sampled; however, no clay resources or coal reserves were identified. Estimates of coal resources will be reported by the U.S. Geological Survey in a joint U.S. Geological Survey-U.S. Bureau of Mines publication. Gravel along the Yellowstone River, a source of agate for private collectors, could also be used as sand and gravel aggregate although material on the south bank of the river is closer to population centers and road systems. Clinker found in the study area could be a source of road metal, but is not well situated in relationship to areas of use. No geothermal resources have been identified although water suitable for direct heat applications may underlie the study area. All the area is leased for oil and gas exploration.

Jan 1, 1985

By Gordon T. Austin

The combined value of production of natural abrasives, which include tripoli, special silica stone, garnet, staurolite, and emery, decreased about 24% in 1992. The decrease in the value of tripoli production was the result of a decrease in total production. Emery decreased owing to a decrease in the volume of the material produced. Special silica stone experienced a significant increase in unit value and decrease in the quantity produced. Garnet showed a 6 % increase in quantity and a 36 % decrease in unit value. Staurolite decreased about 27 % in the quantity produced and value compared with those of 1991. The fused aluminum oxide industry showed a slight increase in the quantity produced and a 4 % increase in the value of production. The silicon carbide industry saw a 7 % increase in the quantity produced and a 10 % increase in the value of production. Combined, the industries increased 4 % in quantity and 6 % in value compared with those of 1991.

Jan 1, 1992

By C. E. Saxon, F. E. Cash

"Adequate lighting for all mining operations would unquestionably tend to promote both safety and efficiency; this would be true not only for men but also for the animals that man impresses into service in mines. The Markeeta Coal Co. and the Alabama Fuel & Iron Co. both operating mines in Alabama, have found that equipping mine mules with portable electric lights is more efficient, much more humane, and far more safe for both men and animals then the more or less usual method of forcing the animal to do its work essentially in darkness.This report is intended to give the mining industry data, that will aid in trying to bring about safe and efficient operation of mines.The authors desire to thank Charles F. DeBardeleben, president, Fred R. Bell, general manager, Hewett Smith, C. H. Shepherd, and R. A. Sensing, superintendents for the Alabama Fuel & Iron Co.; and Charles F. DeBardeleben, Jr., president, and H. M. House, superintendent for the Markeeta Coal Co., for their cooperation in furnishing the data for this paper.The eight mines operated by the Alabama Fuel & Iron Co. and one operated by the Markeeta Coal Co. in Jefferson and St. Clair Counties, Ala., are the only mines in Alabama where mules are provided with portable electric lights, and there are few if any mines in other States in which this system is in use.These two companies are convinced that equipping all mine mules with good lights decreases underground haulage cost by animals by prolonging the useful life of the animals, increasing their efficiency, lessening haulage wrecks and delays on haulage, and increasing production. Last but not least of the advantages would be the more humane treatment of the animals.The nine mines are developed by slopes along the dip of the coal bed, with double-room entries on 200- to 300-foot centers turned right and left off the slopes and with approximately 1 per cent grade in favor of the loads. Rooms are driven up or diagonally up the pitch from these entries.A surface hoist delivers the empties from the surface to the entry sidetracks at the slope and pulls the loads to the surface. From these sidetracks, mules pull one to four wooden cars, each of which holds 1-1/2 to 2-1/2 tons of coal, deliver the empties to the rooms and entry faces, and pull the loads to the slope sidetracks. The mule haul varies from 100 to 3,000 feet; there are no locomotives or trolley wires in any of these nine mines, seven of which are rated as gassy and two as nongassy by the Alabama state Mining Department."

May 1, 1933

By E. G. King

Existing thermodynamic data for compounds of the rare-earth metals are few in number and often inaccurate because, in the past, it was difficult to obtain samples that were pure enough and reasonable in cost--a situation that is rapidly improving. This paper reports the results of low-temperature heat-capacity and high-temperature heat-content measurements for cerous fluoride (CeF3) and supplies the first such published data for a rare-earth fluoride. The low-temperature heat-capacity data cover the temperature range 51°-298° K. and serve to evaluate the entropy at 298.15° K. The high-temperature heat-content data cover the temperature range 298°-1,799° K., including the temperature and heat of fusion. The results are assembled for ready use in thermodynamic calculations. Cerous fluoride is one of the important intermediate compounds in the production of cerium metal.

Jan 1, 1959

By Joseph L. Condon

High-speed movies were taken of crater experiments in two-dimensional plates of Tennessee marble to study craters being formed primarily by stress-wave action. The contribution of gas action to the cratering process was minimized because the two-dimensional models did not contain the expanding gases from the explosive. Four burdens were studied for solid plates and one burden for a segmented plate. After cratering, the plates were reassembled for dye penetrant studies of fracturing. Flyrock velocities were calculated and related to the degree of fracturing, and compared with those from quarry shots. In general, the smallest burdens produced the highest flyrock velocities and the least amount of fracturing. Flyrock velocities compared favorably with initial flyrock velocities in quarry blasts, but did not show step accelerations due to gas effects as did the quarry blasts. The test with a segmented plate was used to simulate cratering in a jointed material and showed that stress-wave effects can be important for crater formation in jointed rocks.

Jan 1, 1972

By P. L. Swanson, A. T. Iannacchione, W. J. Gale

This paper outlines the concepts used to correlate rock failure with microseismic events and presents examples of microseismic monitoring together with associated computer modelling of the rock failure. This study is motivated by the need to develop improved ways to reduce ground control hazards in underground mining. Toward this end we present and compare results from numerical modelling and micro- seismic monitoring studies conducted at several different mine sites. Emphasis is on integrating results obtained with these tools to characterize, and thus increase our understanding of, important mine deformation processes. The ultimate goal is to use this knowledge to design mine structures, and develop mitigation measures, that minimize specific ground control hazards.

By Claude A. Tongish

This Federal Bureau of Mines report presents information on the accumulation and distribution of helium in U.S. natural gas reservoirs. The investigation concerns the relationship or association of helium with geographic location, geologic age, reservoir depth, nitrogen, carbon dioxide, and argon. Although helium is a minor constituent in natural gas, these data show that certain conditions make some reservoirs statistically more favorable than others for the accumulation of helium. The report is based on gas analysis information collected-by the Bureau from 1917 to 1974 from 10,086 gas samples, representing 6,455 reservoirs in 35 States. The occurrence of helium in the reservoirs was 11.5 percent with less than 0.005 percent of helium, 70.9 percent with 0.005 through 0.29 per-cent of helium, and 17.6 percent with 0.30 percent or more of helium in the gas. Results of the various correlations are presented in tables and charts. Relationships have also been determined quantitatively by measures of correlation. The statistical data can be used to determine the environment under which reservoirs with high-helium contents are most likely to occur. These data can be used with other information for predicting the future helium resources of the United States.

Jan 1, 1980

By George H. Schnakenberg

This Bureau of Mines publication describes a passive personal sampling device for N02 in air, developed by the New York University Medical Center under Bureau Grant G0133066. The sampler has been successfully demonstrated in the field and in the laboratory. In corroborative laboratory trials the agreement with reference method is excellent. The overall accuracy is approximately ±5 pct of reading to a precision of about ±l pct. All evidence indicates that these samplers should indicate the time-weighted-average N02 concentration to the above accuracy and precision equally well in the field since effects of wind velocity and relative humidity are negligible and the effects of temperature are about 0.1 pct per °F. The duration of exposure and the approximate temperature are the only data that need to be collected in the field. A two-step analysis procedure in field or service laboratory is then used to obtain the total cumulated exposure to N02 in parts per million-hours (ppm times hours), which can be converted to the time-weighted-average concentration of N02 in ppm by dividing cumulated exposure by the duration of the exposure.

Jan 1, 1976

By S. R. Zimmerley

Recent investigations of finely ground materials have verified Rittinger's law of crushing.4, This law states that the surface produced is proportional to the work expended in the crushing operation. Thus, for a unit of work applied to crushing quartz a definite amount of surface will be produced. Obviously, this amount of work applied to some other mineral will not produce equivalent surface. It follows that in an investigation of mill practice, where ore is being crashed, the relative crushing resistance of the component minerals must be known. In a previous investigation of the Rittinger law,5 the crashing resistance that is, the work required to produce a unit of surface - was accurately determined for quartz. The surface values were obtained by means of the rite of dissolution of quartz in hydrofluoric acid.6 If it were possible so to measure surface on other minerals the determination of relative crushing, resistance would be a simple matter; however, the results obtained on minerals other than quartz by a dissolution method were not encouraging. Moreover, if accurate values could be obtained by dissolution this method could probably never be used on a mixture of minerals such as occurs in an ore.

Jan 1, 1929

By John Durkin

Electromagnetic narrow-band signals were transmitted through the earth at 27 coal mines located throughout the United States. From those Bureau of Mines tests, apparent earth conductivity values were derived based upon a homogeneous half-space model of the earth. The derived conductivity values were found to be inversely proportional to the transmitted frequency and mine depth. A linear regression model relating the logarithm of the conductivity to the mine depth was formulated, and the results indicate that the mine depth can be an adequate predictor of the apparent earth conductivity above coal mines. Apparent earth conductivity was found to decrease with mine depth.

Jan 1, 1984

By John Durkin

Electromagnetic narrow-band signals were transmitted through the earth at 27 coal mines located throughout the United States. From those Bureau of Mines tests, apparent earth conductivity values were derived based upon a homogeneous half-space model of the earth. The derived conductivity values were found to be inversely proportional to the transmitted frequency and mine depth. A linear regression model relating the logarithm of the conductivity to the mine depth was formulated, and the results indicate that the mine depth can be an adequate predictor of the apparent earth conductivity above coal mines. Apparent earth conductivity was found to decrease with mine depth.

Jan 1, 1984

By Kenneth H. Johnston

This report describes an in situ combustion project and three waterflood projects in Allen, Anderson, and Wilson Counties, Kansas, that will be visited during the 1964 annual tour of the Kansas-Oklahoma Waterflood Association. Among the unique features of the projects are the movement of heavy crude oil through the reservoir and into the wellbore with energy furnished by burning s portion of the crude oil therein. Another feature is the simultaneous injection of C02 and water, through separate tubing into input wells during early development, to increase injectivity at moderate pressures, Discussion of individual projects includes information on their early history, source and treatment of injection fluids, oil production-decline curves, and the results of water injection on oil production.

Jan 1, 1964

By E. C. Lane

The motor gasoline that is bring marketed in the United States this stunner is slightly more volatile than that sold a year ago. During the past eight years the Bureau of Mines has made semi-annual surveys of the gaoline marketed in the United States, the survey just completed being the sixteenth in the series. The cities in which samples have been collected have been chosen as representative of the more important marketing territories as it is obviously impracticable to obtain a sample of every gasoline sold in the entire country.

Jan 1, 1927

By Bernadette Michalski

Although hydrocarbons accounted for more than 60% of Bahrain's income and more than 80% of export earnings, this island nation sustained one of the more diversified economies in the Gulf Region. The availability of low-cost natural gas for electric power has fostered the development of a significant aluminum refining and manufacturing industry with emphasis on vertical integration. The Bahraini iron pelletization plant, closed since 1986 due to financial problems, was scheduled to reopen by early 1989. Commodity Review Metals.-Aluminum.-Aluminium Bah-rain Bsc (Alba) attained record high production levels in 1988 taking advantage of favorable aluminum prices, which averaged over $2,000 per ton as compared with less than $1,500 per ton in 1987. Net aluminum production was nearly 13,000 tons over design capacity. Fewer standard ingots (52,081 tons as compared with 79,685 in 1987) were produced as Alba concentrated on higher value added products such as rolling ingots (42,324 tons as compared with 32,125 tons) and extrusion billets (60,934 tons as compared with 46,618 tons).

Jan 1, 1990

By Raja V. Rarnani, Robert L. Frantz

"Co-Directors, Generic Mineral Technology Center for Respirable DustEarly in the 1980s, the U.S. Bureau of Mines initiated the concept of the Generic Center, incorporating it into its mining research program, and in 1983, the Generic Mineral Technology Center for Respirable Dust was established. The Generic Center concept was first envisioned by the U.S. Bureau of Mines as a way to bring together the various different scientific, engineering and medical research interests in the respirable dust area to effect a coordinated and efficient organization for advancing knowledge in that field. The result was a combination of the collective talents and skills of more than 100 scientists, engineers, medical personnel and graduate students, through the formation of a consortium of five major research universities, including medical facilities, to perform respirable dust research. The Generic Mineral Technology Center for Respirable Dust consortium comprises The Pennsylvania State University (with its Hershey Medical Center) and West Virginia University (with its Medical Center) as the lead universities and the University of Minnesota, Massachusetts Institute of Technology and Michigan Technological University as affiliates.Although respirable dust-related disease remains the nation's worst industrial hazard, the fundamental understanding of all aspects of respirable dust associated with the mining and milling industries, including the interaction of dust and lungs, has grown significantly over the past near-decade toward the larger effort to reduce the incidence and severity of disease caused by respirable dust. Continued progress toward making the mine work environment cleaner and healthier remains the immediate objective of the Respirable Dust Center.The Respirable Dust Center's research program and technology transfer activities, described in this paper, exemplify the Generic Center concept first envisioned by the U.S. Bureau of Mines. Interdisciplinary and interactive studies continue to result in significant progress toward making mine atmospheres cleaner and healthier."

Jan 1, 1995

By Frank E. Cash

The iron-ore ranges in the Lake Superior district are the liarquette in Michigan, Menominee and Gogebic in Michigan end Wisconsin, and the Vermilion, Mesabi, and Cuvuna in Minnesota. These ranges produce about 85 percent of the iron ore mined in the United States. Accident experience in connection with this production is better than that of the regions producing the remaining 15 percent. Production and shipments vary slightly from year to year but closely approximate each other over a period of years. During the 4-year period 1940 to 1943, inclusive, 323,667,599 long tons of iron ore was shipped from the Lake Superior district.4/ Michigan and Wisconsin shipped 65,386,608 tons, or 20.2 percent of the total, and employed approximately 15,000 men; Minnesota shipped 258,280,991 tons, or 79.8 percent of the total, and employed approximately 10,000 men. The tons produced per man employed is much, greater in Minnesota than in Michigan and Wisconsin owing to the large open-cut production in Minnesota.

Jan 1, 1945

By G. L. Neumann

"INTRODUCTION AND SUMMARYThe Guymard mine in Orange County, N. Y., is reported to have been discovered in 1862 and mined until 1876, producing 10,000 tons of lead and zinc ore. 2/The property was examined by an engineer of the Bureau of Mines 3/ in 1948. Development work was done by the Bureau in April and May 1949 and March 1950. During these two periods four drill holes totaling 2,090 feet were completed. The mineralized sections of the core were sampled and assayed.ACKNOWLEDGMENTSThe diamond drilling was conducted under the general supervision of McHenry Mosier, chief, Mining Development Branch, Minerals Technology Division, Region VIII, and the direct supervision of Kenneth M. Earl and the writer as project engineers. Drill cores were logged by Paul K. Sims of the Federal Geological Survey. Chemical analyses were made by the Bruce Williams laboratories, Joplin, Mo., and the Minerals Processing Branch, Minerals Technology Division, Region VIII, Bureau of Mines, under the general supervision of Paul M. Ambrose, chief, and the direct supervision of Howard F. Carl, chief, Physical and Chemical Section.LOCATION AND ACCESSIBILITYThe Guymard deposit (see fig. 1) is on the west slope of Mount Hope, Orange County, N. Y., 1,500 feet northeast of Lake Guymard.Graham station, near the deposit, is on the Erie Railroad about 8 miles north of Port Jervis and 4 miles south of Otisville."

Aug 1, 1952