Search Documents

By Robert A. Speirer, Richard G. Burdick

Methods of detecting geologic faults and other linear features by means of processed LANDSAT satellite images have gained prominence during the past several years . There have been numerous programs written to pick these " lineaments , " but they have been almost universally tailored to large computers . This Bureau of Mines report describes a detection method developed for use with a minicomputer . The method comprises a suite of programs that scans an image for all " potential " lineaments . From this partially analyzed data , the final lineaments are picked by another routine . The method was field tested in an area of south- central Wyoming , and results indicated good agreement between computer- picked lineaments and ground features . Most of the known geologic faults in the area were picked by the method . Such features as roads and trails were also picked but were easily distinguished from faults during field inspection . The method is relatively new but promises to be a viable reconnaissance technique for the mining industry in geologic structural analysis .

Jan 1, 1965

By Arnold B. Hubbard

A thermal decomposition study of the kerogen in three Colorado oil shales was made at different temperatures by heating the shales in the absence of oxygen at atmospheric pressure and measuring the decomposition products (gas, oil, and bitumen) formed. From these data the specific reaction rates, "k", for the thermal decomposition of kerogen were determined for each temperature studied, making it possible to calculate the time required to accomplish a given amount of decomposition within the temperature range. The influence of temperature on reaction rates was presented by plotting the data according to the Arrhenius equation, thus providing a means of estimating the values of "k" for any temperature within the range of this study. It was found that the specific reaction rates for the thermal decomposition of the kerogen in the three sampler were comparatively equal at corresponding temperatures.

Jan 1, 1950

By Janine Pierce, Robert Larson, Christine Raasch

The vibration and impact environment for crew members on locomotives has been investigated in a series of studies conducted by Exponent Failure Analysis Associates (Exponent) beginning in 1990. Locomotive cab vibration and impact levels were measured on a variety of locomotive models operating over many different track sections across the Union Pacific, Burlington Northern Santa Fe, CSX, Norfolk Southern, and CONRAIL systems. The comfort and health implications of exposure to the measured locomotive vibration levels were evaluated by comparison with the human vibration exposure boundaries given in the International Standards Organization (ISO) standard 2631-1:1997, the British Standard 6841:1987, European Union (EU) Directive 2002/44/EC, measurements made by Exponent on various commercial and recreational vehicles, and vibration exposure measurement data found in the literature. Methods Initially, vibration levels experienced by locomotive crews were measured and recorded at incremental speeds covering the range of normal train operation. In 2003, a method of measuring the vibration exposure continuously by means of a digital recorder was developed, allowing the vibration level over the entire run or crew shift to be analyzed. For each seating location measured, acceleration was recorded on the seat surface beneath the ischial tuberosities (pelvis) of the seated crew member and on the cab floor directly under the seat. At each of the locations, triaxial accelerometers were used to measure the vibration along the longitudinal, lateral, and vertical axes. Since the vibration environment varies throughout the route, and locomotive vibration levels have been found to be primarily speed dependent, a speed sensor was used to continuously measure the speed of the train. To evaluate the recorded vibrations levels, the data was divided into two-minute segments, which were each processed per the 1997 ISO standard for weighted RMS vibration levels and Vibration Dose Values (VDV). Additionally, PSDs and 1/3 Octave RMS values were calculated to determine the frequency content of the vibration. For each two-minute segment, the average speed of the locomotive was calculated to allow for correlation with the recorded vibration exposure values. The resulting exposure values for the entire run were calculated by combining the data from all of the two-minute segments. Since introducing the continuous method of recording acceleration, 23 seating locations have been recorded on 11 locomotives traveling 11 different routes across various parts of the United States. One of the routes was a shift of ‘yard work’, traveling back and forth in a rail yard coupling train cars together. Results A guide to interpreting weighted acceleration values with respect to health is given in Annex B of the 1997 ISO standard. A health guidance caution zone is defined to indicate the

Jan 6, 2006

By Raja V. Rarnani, Robert L. Frantz

"The more than 75 research projects funded throughout the first 10 years of the Dust Center's operation have resulted in numerous cumulative findings fulfilling the goals of the Center. These project descriptions present the methodologies and project-to-project relationships leading to their various accomplishments and demonstrate the mesh between project objectives and Center goals.To develop equipment for collecting respirable dust samples.To develop experimental methods for particle-by-particle characterization of morphology, size, and chemistry.To develop experimental methods for overall respirable dust sample characterization of size distribution, chemistry, and crystallography.The project directly addresses the Center's goals to enhance the understanding of the scientific and engineering characteristics of fine and respirable mineral particles found in mining and milling atmospheres and to establish the relationship between natural and cultural factors (mine geology, mineralogy, mining and milling methods, equipment, and control measures) in the generation of fine particles. The project also aims to contribute to the development of control mechanisms for reducing ambient respirable dust concentrations and worker exposures.The work on this project is related to similar work on Coal Mine Dust Characterization (Project No. 2701/MN1) and Characterization of Dust Particles (Project No. 4203/PS3).Airborne dust sampling was performed at the following locations: 1) a sand and gravel quarry in Southern New Hampshire, 2) a welding facility, 3) a ceramic powder facility, 4) a metal powder facility, and 5) the air in Cambridge, Massachusetts. A portable sampling box incorporating two Sierra personal cascade impactors was designed and produced. At a 2-LPM flow rate, the effective cut-off diameters of the Sierra impactors were 10.0, 6.0, 3.5, 2.0, 0.9, and 0.5 mm, respectively, for each stage, and the air passed through a PVC filter after the last stage. In addition, the sampling box contained a total respirable dust filter. The substrates were weighed carefully before and after collection, and the weight increases were recorded. All films, foils, and filters were put in the balance chamber for more than 8 hours to stabilize the temperature and humidity before weighing. A Cash 21 microbalance (±0.001 mg) was used to weigh the Mylar films, SS films, and filters."

Jan 1, 1995

By P. A. Lawless

The objective of the research performed A for the Bureau of Mines on this contract was to develop a portable instrument for the detection of carbon monoxide (CO) in a mine environment. The desired characteristics were sensitivity and specificity for CO with a stable calibration. The sensor of the instrument was to be of metal oxide composition, requiring low power for compatibility with the types of batteries presently used in personal equipment in mines. The solid state design was also desired for ruggedness and small size. A key design feature of the instrument was to be provided by adherence to the intrinsic safety design requirements for electrical equipments operated in potentially exposive mine atmosphere. The Research Triangle Institute has prior experience in developing a solid state oxygen sensor using a thin film of zinc-oxide (Ref. 1) and experience in fabricating thin film devices. Solid state sensors utilized by other workers (Refs. 2, 3, 4, 5, 6) have included metal and semiconductor films and crystals of materials like carbon and aluminum oxide for the measurement of water vapor in the air and have relied upon measuring resistance and capacitance changes in the sensor in response to adsorbed vapors or gases. Since the effect of carbon monoxide in changing the resistance of various materials such as molybdenum, platinum, and zinc oxide had been reported (Refs. 7, 8, 9, 10), the requirements appeared to be realisable, although it was recognized even at the inception of the work that specificity to carbon monoxide might require the incorporation of more than one sensor.

Jan 1, 1976

By J. William Ganser

This paper is one of a series being prepared by the United States Bureau of Mines describing mining and milling methods and costs at cement-plant quarries throughout the United States. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent local operating expenditures only and not total production costs. It is recognized that publication of total production costs may in some instances cause embarrassment to individual producers as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue.

Jan 1, 1931

Construction workers may be exposed to hazardous dust containing silica when working in enclosed cabs during construction activities. The National Institute for Occupational Safety and Health (NIOSH) found that equipment operator exposure could be reduced by retrofitting air pressurization and filtration systems on existing cabs, using sweeping compounds on soiled floors, and implementing a dust control program.

Jan 1, 2009

By F. E. Diebold

The methodology for describing the geochemistry of elements in a coal seam have been developed. This has been applied to the Rosebud Coal Seam, which is an economically important member of the subbituminous coals of the Fort Union Formation in Eastern Montana. The method development has involved a detailed study of two popular techniques for determining the metal geochemistry of coal, namely, whole coal analyses and coal physical fractionation. The mathematically contrived element associations (whole coal analyses technique) and the element concentration trends in the float and sink fractions (physical fractionation technique) are considered to lead to only qualitative conclusions concerning the chemical associations of the elements in coals. Additionally, the processes taking place with the coal during low temperature ashing in an oxygen plasma are experimentally investigated and shown to be of sufficeint extent that the use of such low temperature ash for deciphering element geochemistry is questionable. The method developed in this study is a chemical fractionation that involves the sequential leaching of coal with water, 0.5 N HC1, 3 N HC1, 2 N HNO3, and 48% HF. These leach solutions are shown to selectively dissolve the predominate inorganic phases, sulfates, Ca and Mg carbonates, Fe sulfides and K alumino-silicates and quartz, respectively. These phases were identified with the use of XRD, SEM, EM and leaches (water and 0.3 N HC1) of whole coal and low temperature ash. The incorporation of the anion-exchange step in the leaching scheme was investigated and was observed to warrant further study of such intensity to be, at the time, unuseable. The use of this sequential leaching technique on several coal samples from the same seam generates element concentration trends that can be quantitatively interpreted with respect to the chemical associations of the minor and trace metals in the coal seam. The properties of the various seams of economic importance in the Fort Union Formation in Eastern Montana are compiled and presented. The subsequent conclusion is that there is not a large variation in the properties of these coal seams and that the variations within the Rosebud are within one order of magnitude. The chemical fractionation technique, investigated in this study, was applied to composite tipple samples of the Rosebud seam. Each composite sample represented 76,800 tons of coal. A minimum of 32% of the Ca and Mg are present as separate water soluble sulfates. An excess of the sulfate ion in the water extracts shows the predominating influence of the ion exchange capacity of the organic compounds in the coal. Based upon the CO content of the coal and the HC1 leachate data, 25 to 30% of the alkaline earth elements exist as separate carbonates and the remainder are associated with the organic compounds. The small fraction of the illite that dissolves in the HC1 and HNO3 leachates accounts for the K and Al. Slight dissolution of the pyrite in the HCl solvent occurs, the small amounts of Li and As do not relate to any known phase and Mn is present as a separate carbonate phase. Fe and a significant amount of the As exist in the pyrite that is dissolved in the HNO. Se is equally partitioned between the pyrite and the organic compound~. Most of the trace elements are found in the HF solutions. Li, V, and Cr were interpreted to be associated with the clay minerals (kaolinite and illite). Ni and Pb appear to be present as separate phases and 50% of the Hg is HF soluble but is not chemically related to any known inorganic phase.

Jan 1, 1983

By J. W. Eckerd

This report describes an investigation of the technical feasibility of using a conventional commercial-size (10-ft. i.d.), rotating grate, dry-ash-removal type gas producer to make producer gas from chestnut-size bone anthracite. Test instruments were installed, and some minor changes were made in the equipment to handle the large quantities of materials expected. Extensive tests, lasting about 4 weeks, were planned, using 35 to 50 percent ash chestnut anthracite bone. However, operations were suspended after 8 days when it became apparent that to use this type of fuel satisfactorily substantial changes in equipment and operating procedures would be required. Nevertheless, enough data were obtained to indicate that gas could be produced continuously and routinely from bone coal in this type of producer whenever conditions justified the necessary development work.

Jan 1, 1960

By E. C. Perkins

Preliminary experiments are reported utilizing bacteria to leach manganese from a variety of domestic low grade manganiferous materials. In two large leaches manganese extraction ranged from 71.7 to 92.5 percent, and the products analyzed over 48 percent manganese. Nutrient requirements and leaching time experiments were made. The mechanism of leaching is not understood, but is different than the mechanism encountered in the microorganism accelerated leaching of copper in the presence of sulfide minerals.

Jan 1, 1962

By Robert N. Roby

Deposits of iron ore in Judith Basin County, Mont., generally referred to as the Running Wolf deposits, were examined by an engineer of the Bureau of Mines in August 1942. During the Summer of 1943 the Federal Geological Survey made a reconnaissance survey of, the Running Wolf Iron district and also made a detailed study and a topographic and geological map of the eastern end of the district. Two deposits of iron ore at the eastern end of the district were trenched and drilled by the Bureau of Mines during the fall and winter of 1943-44, This report presents the factual data obtained from the trenching and drilling' operations. The iron deposits of thy Running Wolf district are accessible from Stanford, Mont., by 14 to 16 miles of county highway and 2 to 3 miles of rough mountain road or trails (see fig. 1). No shipments of ore have been made from of these deposits. The ore is a replacement of Madison limestone at the contact with syenite porphyry. The contact can be traced for about 6 miles in a general northwest direction. 'At least five. deposits occur along this contact.

Jan 1, 1949

By J. Fletcher Smoak

Consumption of abrasive materials in the United States in 1981 was approximately $340 million, of which 37 % was industrial diamond (natural and synthetic), 39% manufactured abrasives, and 24% natural abrasives. Production and shipments of natural abrasives, excluding emery and industrial diamond, decreased in quantity 9% and 7%, respectively, when compared with that of 1980. Emery showed the largest change in output, decreasing 30% in quantity and 20% in value. Production of nonmetallic .manufactured abrasives material plus shipments of metallic abrasives material decreased 5% in quantity but increased 4% in value. Nonmetallic manufactured abrasives consisted of aluminum oxide (fused) and crude silicon carbide produced in the United States and Canada and accounted for 63% of the value of all manufactured abrasives. Metallic abrasives shipments included chilled and annealed iron shot and grit, steel shot and grit, plus cut wire, aluminum, and stainless steel shot and equaled 37 % of the value of all manufactured abrasives.

Jan 1, 1982

By H. S. Kalman

A table of factors for rapid, accurate calculation of the volume of pure helium in cylindrical steel containers, at base conditions of 14.7 psia and 70° F, is presented. The table covers a pressure range from 10 to 10,000 psin in 10-psi increments and a temperature range of 0° to 120° F in 2° increments. The volume of helium is calculated from the observed pressure and temperature of the helium, expressed as a factor from the table, and the known internal volume of the container. The calculation requires a single multiplication. A discussion and evaluation of the accuracy obtainable and a derivation of the formula used (which takes into account compressibility of helium, thermal expansion of steel containers, and the stretch of steel due to internal pressure) are presented. An example showing how the table can be used is given also.

Jan 1, 1968

By M. S. Oudenhoven

The Bureau of Mines conducted an investigation to determine the theoretical stress distribution in the vicinity of explosively expanded rock bolt anchors independent of their bolts. Plane-strain solutions applicable to this problem were obtained by combining the field pressure with the uniform pressure that would be produced by vertically placed anchors having 2-, 3-, and 4-foot spacings. High rock stress which would be produced by an anchor was localized, as would be expected from St. Venant's effect, and increased as the field pressure decreased.

Jan 1, 1967

By Arne Landsberg

The Bureau of Mines measured the vapor pressure of FeC12 , FeBr2, FeI2, Sb, Bi, Cd, Mg, Pb, FeC13 , and VCl2 using the Knudsen-and torsion-effusion methods, and on FeC13 -NaC1 mixtures, Au2Cl6, and MgNi2 using only the Knudsen method. Apparent vapor pressures calculated from the experimental data vary with orifice size and method of determination. Reaction with residual oxygen in the instruments was noted to have an effect on the iron halide data. Vapor pressure curves plotted as log P versus 1/T (where P is pressure and T is absolute temperature) for one substance using several orifice sizes tended to converge at a single point when extrapolated beyond the experimental region. All of the data, except those of VC12, agree with previously published results. The importance of comparing effusion measurements with those obtained by other methods and the variations encountered with various orifice sizes are discussed.

Jan 1, 1977

By James R. Boyle

The value of mineral production in-creased 13% in 1977. Nearly all commodities registered an increase in production and value, continuing a trend that started in 1976. In addition, practically all commodities registered an increase in unit value. Alabama led the Nation in the production of crushed marble, was second in bauxite and scrap mica third in kaolin and oyster shell, and fourth in bentonite, dimension marble, and fire clay.

Jan 1, 1981

By K. L. Paciorek

The primary objective of this final phase of Contract No. H0133004 was to provide a description of all experimental assemblies and procedures used throughout this project in such a detail as to permit duplication of the tests in any other laboratory. A further objective was to summarize and evaluate all results generated throughout the duration of this program and to tabulate all the materials and data in such a manner as to allow this report to be used as a reference index for specific compositions or groups of compositions regarding potential hazards arising from their use .in underground coal mining operations. The report also contains an updated survey of the literature on thermal oxidative degradation of compositions investigated under this contract.

Jan 1, 1978

By D. Harrington

Every few weeks United States newspapers of 25 or 30 years age ran scare-heads telling of some mine disaster, which was a first-page attraction for a day or two and then was forgotton until another disaster occurred a few weeks later. Interspersed with these disasters were the so-called sniping mine accidents, causing the death of one or two mine workers. The summation of all types of mine fatalities usually exceeded 3,000 a year. In the period 1906-10, inclusive, there wore 84 major explosion disasters (or about 17 per year) in united States coal mines; the fatalities resulting from those disasters numbered 2,388 for the 5-year period. These frightful catastrophies helped to cause the total number of fatalities in our coal mines for the 5 years (including the fatalities from major explosions) to reach the enormous total of 13,288, an average of 2,658 per year. In addition, some hundreds of other typos of mining accidents swelled the annual fatality list to upwards of 3,000. This admittedly deplorable condition created so much Nation-wide comment that Congress was impressed with the necessity of having something done by the Federal Government with a view to trying to halt at least sonic of the excessive loss of life in our mines; in consequence, the Bureau of Mines was created and began to function in July 1910.

Jan 1, 1935

By Chas. F. Jackson

The work of the mining division is divided between seven sections, each in charge of a supervising engineer, as follows: 1. Metal-mining methods section, the supervising engineer of which is also supervising engineer of the Southwest Experiment Station at Tucson, Ariz. 2. Metal-mining research section. 3. Nonmetal minim section. 4. Coal-mining section. 5. Mine-ventilation section. 6. Mineral-industries survey section. 7. Electrical section. The names of the sections indicate broadly the fields covered by each, and in the following pages the objectives and type of work of each section will be summarized briefly and the active problems listed. The work done during the calendar year 1936 will also be summarized.

Jan 1, 1937

The STATE MINERAL SUMMARIES publication provides estimated data and summaries of mineral activities at the State level for 1989. Most of the estimates are based on nine months data. These summaries have been prepared in cooperation with State geological surveys or related agencies. Individual State summaries are published separately as State Mineral Industry Surveys and copies can be obtained from the appropriate State Activities field office.

Jan 1, 1990