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By Wilbur I. Duvall

This paper presents arguments which show that a velocity seismograph should be used to measure building and ground vibrations produced by blasting . However , portable velocity seismographs suitable for this type of measurement are not commercially available . The paper describes how a velocity seismograph can be assembled from commercially available velocity gages , amplifiers , and recorders . Also , specifications are given which could be used in the design and manufacture of a portable velocity seismograph suitable for measuring vibrations from blasting .

Jan 1, 1964

"Contained in this chapter is a listing of the publications and reference books which have come about as a result of respirable dust research performed by faculty, staff and graduate students in the Generic Mineral Technology Center for Respirable Dust at The Pennsylvania State University, West Virginia University, University of Minnesota, Massachusetts Institute of Technology, and Michigan Technological University. These publications have appeared in scientific journals, proceedings of the national and international symposiums, and professional meetings. Complete citations of the publications can be found in Volumes 3 through 6 and Volume 8 of this series. The agenda of the last annual GMTC seminar, held at West Virginia University on February 1 - 2, 1988, follows. The project presentations are organized under the five research areas. All projects currently active were presented to the Advisory Committee. New project submissions were not. The authors were allotted thirteen (13) minutes for their presentations; the remainder of the twenty (20) minutes allotted for each project was used for introductions, transitions, and questioning by the Advisory Committee. Each author used a standard format for presentation of his/her materials for review; handout materials were distributed to the Advisory Committee for reference. Opening remarks were made by Dr. Richard Bajura of West Virginia University and Dean Robert L. Frantz and Dr. Raja V. Ramani of The Pennsylvania State University.The Generic Mineral Technology Center for Respirable Dust is funded by the U.S. Bureau of Mines through the Mining and Mineral Resources Research Institute Program. The opinions and conclusions expressed in these papers are those of the authors alone and do not represent the opinions of the Generic Mineral Technology"

Aug 31, 1989

By Oliver Bowles

Granites are classed as igneous rocks ; they have been formed by the solidification of rock magmas or solutions from deep within the earth . It is an almost invariable law of nature that magmas which cool quickly form fine- grained or glassy rocks , while those that cool slowly are completely crystallized and are coarser- grained . Granites , being of the latter class , are regarded as having attained their solid form at considerable depth below the surface under conditions of high temperature and pressure . The constituent minerals crystallized out slowly , the crystals interlocking with one another . The great depth of overlying rocks that must have been present when crystallization took place has been removed by erosion over large areas on the surface of the earth , in consequence of which granites appear at or near the surface in many localities . The chief minerals of which granites are formed are feldspars , quartz , and either mica or hornblende . All the essential constituents except mica are as hard as , or harder than steel , therefore granites are difficult rocks to cut and dress . Granites are usually red , pink , or gray , depending on the color of the feldspars . If hornblende or black mica is abundant the rock may be dark green or almost black . Granites are characterized by massive homogeneous texture . They are classified as fine- grained , medium- grained , or coarse - grained . Medium- grained granites are those in which the feldspar crystals average about one- fourth inch in diameter . If relatively coarsegrained crystals appear in a fine -grained ground mass the rock is designated a porphyritic granite . Uniformity in texture and grain size are desirable in building and ornamental stone , although occasionally rocks of variable texture , such as the porphyritic granites , are used . A rock may have the mineral constituents of a granite but show a banded or platy structure due to recrystallization , folding , or other changes while the rock was in a plastic or semimolten condition . Such metamorphic rocks are called granite gneisses . They are used occasionally for building purposes but not as commonly as the uniformly textured granites . - Granites are named from the most abundant mineral other than quartz and feldspar that they contain , being called , for example , biotite granite or hornblende granite . - Commercially other igneous rocks granitoid in texture but more properly classified as syenites , diorites , or gabbros may be classed as granites . Thus the " black granite " of Little Falls , Minn . , is a diorite , and the " black granite " of Eastern Pennsylvania consists of diabase or gabbro . The question is sometimes raised as to the depth to which a granite occurrence may extend . In this respect granites differ notably from limestones , sandstones , or other sedimentary rocks . The sediments were originally laid down in relatively thin beds , and individual formations providing rock of economic value may be quite limited in thickness . Usually the usable beds range between 40 and 200 feet in thickness . On the other hand , granite comes up from below . Its depth is unknown , but in general is very great . It may even be measurable in miles . The reserves of material at depth are to be measured , therefore , by the economic depth of working rather than by the vertical extent of the rock mass . Exceptionally , granites of commercial quality may occur in sills or sheets of limited thickness flanked on either side by rocks of different character , as , for example , at Westerly , R. I.

May 1, 1930

By Paul W. Jeran

This Bureau of Mines report has been prepared to provide a means whereby mineworkers without specific geologic training can recognize and record the existence of potentially hazardous geologic features encountered in coal mines. Each geologic feature described in this report has been implicated in roof failure. Through the recording of the observations of mineworkers, based on this report, a geologic map of mine workings and the associated ground control problems can be compiled. From such maps, the trends of changes and features can be determined and projected ahead of mining. The face crew can be alerted to a potential problem and what to look for as the face is advanced.

Jan 1, 1983

By J. E. Hamak

This publication contains analyses and related source data for 266 natural gas samples from 20 States and 2 foreign countries. None of the analyses have been previously published in annual reports. All samples were obtained and analyzed as part of the U.S. Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by mass spectrometer and chromatograph.

Jan 1, 1992

By Donald H. Mullen, Walter R. Storms

"INTRODUCTION The Copper Flat area of the Central mining district, Grant County, N. Mex., has been visited by numerous engineers 4/ of the Bureau of Mines and geologists 5/ of the Federal Geological Survey. In December 1944 the Bureau. 6/ proposed that geophysical work be done in that area in order to locate favorable sites for future company exploratory and development work. This geo-physical work was begun early in 1945 but never fully completed because of insufficient funds. The engineers who made the survey recommended that more work be done, especially to locate the bottom of the Copper Flat laccolith by resistivity-depth surveys. All known minable zinc-lead ore bodies had been found above this laccolith in the Copper Flat mine, but it was thought that other minable ore deposits should occur in favorable limestones beneath it. The geophysicists also recommended core drilling beneath the laccolith.In the summer of 1946, following some mapping by S. G. Lasky of the Federal Geological Survey, funds were appropriated for a Bureau of Mines project in the Copper Flat area. The project was completed in June 1947. 8/"

Apr 1, 1948

By Richard D. Miller, Geraldine P. Norrell

This publication contains routine analyses and related source data for 295 natural gas samples from 18 States collected during calendar year 1963 as part of a continuous survey of the United States for occurrences of helium in natural gas. This survey has been conducted by the Bureau of Mines since 1917. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4863 and 576.4 Five previous publications have been made to present the results of 5,998 gas analyses made by the Bureau of Mines Helium Activity , prior to 1963. The first three , Bulletin 486,5 Bulletin 576,6 and Bulletin 617,7/ contain analyses and source data on 5,214 gas samples collected from 1917 to January 1 , 1961. The fourth and fifth publications , which are published as Information Circulars , supplement the three Bulletins and contain 784 analyses of samples collected during 1961 and 1962. The present Information Circular is the third annual publication supplementing the three Bulletins .

Jan 1, 1965

By L. C. IlsLey

The observations made by Bureau of Mines engineers of permissible equipment installed in about 40 mines have indicated a chance for improvement in designs calling for the use of bolts , screws , studs , etc. , especially with respect to bolt sizes and protection from mechanical injury .

May 1, 1931

By D. A. Reynolds, J. D. Davis

During early development of the blast furnace, Connellsville coke made entirely from Pittsburgh-bed coal proved to be an excellent fuel. The need for blending coking coals arose as the industry grew and it became necessary to carbonize coals having voking properties inferior to those of Pittsburgh coal Most coals carbonized today in continental Europe and this country are blonded: This practise has improved the quality of coke and permitted the utilization of coals that would yield inferior coke, if carbonized sepa- rately, The depletion of the world's better coking coals, which has been noted by leading coal technologists,2/4/wes accelerated during the recent war and. It is important, therefore, that reserves be evaluated and conserved. In the principal, steel-producing sections of this country, Pocahontas coals have been blended so extensively that the terms "low-volatile coking coal": and. "Pocahontas" have become virtually synonymous. Other low-volatile coals. have been used to manufacture metallurgical coke and will be used more extensively as, the supply of the better known and more accessible Pocahontas coals decreases. Recognizing the need for augmenting the supply of high-rank coking coals, the Bureau of Mines has included both low- and medium-volatile coals in its Survey of the Carbonizing Properties of American Coals, which was started with the cooperation of the American Gas Association in 1929. Twenty coals, 12 of low-volatile and 8 of medium-volatile rank, have been blended with high-volatile A Pittsburgh-bed coal, and five standard low- volatile coals have been blended with various high-volatile coals. Most of the results of carbonization tests of these coals and their blends have been

May 1, 1946

By C. Ortuglio

The Bureau of Mines developed equations to determine the relationship of yields and products obtained from BM-AGA carbonization in 13-and l8-inch-diameter retorts. The developed equations indicate that results of carbonization in l8-inch-diameter retorts can be predicted from results obtained with l3-inch-diameter retorts.

Jan 1, 1966

By Raymond L. Lowrie

Coal deposits in the Boulder-Weld County coalfield in Colorado are analyzed in relation to economic factors governing the growth, stability, and competitive potential of the coal industry. Recoverable reserves, estimated to be 571 million tons, are discussed in detail, particularly those in the Erie and Frederick Quadrangles. Geology of the coal measures, quantity and quality of water resources, and chemical and physical properties of the coal are described. Coal production factors, including mining techniques and equipment, labor requirements, transportation facilities and rates, and markets, are considered for coal's position in competition with alternate fuels. Growth of the fuels market, through increasing thermal-electric power generation in the Denver Metropolitan Area, will stimulate coal production in Colorado. Reserves of the contiguous Boulder-Weld coalfield, if mined in a sustained, year-round, high-tonnage operation, could be used to supply much of that fuel demand.

Jan 1, 1966

By Martin A. Elliott

"INTRODUCTION During the recent war the Bureau of Mines was requested to obtain in¬formation on the temperature at which ammonium nitrate mixed with certa: contaminants would react rapidly. This information was desired in connection with an investigation of an explosion that had occurred during the evaporation, by air agitation, of volutions containing ammonium nitrate in which compressor oil that might have passed the filters was suspected of being a contaminant.During the course of this work it was found that mixtures of ammonium nitrate and zinc reacted rapidly at comparatively low temperatures: and since zinc could not positively be eliminated as a contaminant in the explosion in question, a series of tests was carried out, not only with mixtures of ammonium nitrate and compressor oil but also ammonium nitrate and zinc with and without oil. A few experiments were made with metals other than zinc.The investigation was not as extensive as might have been desired, owing to limitations -in time. The results are presented at this time in view of their current interest in connection with the Texas City disaster, in which a large quantity of ammonium nitrate detonated in the holds of two ships."

Mar 1, 1948

By W. T. Abel

Laboratory tests were conducted with a closed, recycling system to evaluate the effectiveness of solid-in-gas suspensions as heat transport mediums. Micronized graphite in helium or nitrogen was circulated by a centrifugal compressor to determine the feasibility of the method and heat transfer capabilities of the mediums. Suspensions were circulated without plugging or eroding the compressor or piping. At low flowrates and light (0.1 to 0.2 volume-percent) graphite loadings, slightly less power was required to transport a given amount of heat with suspensions than with helium alone. Graphite deposition on the heat exchange surfaces of the cooler decreased the heat transfer effectiveness at higher solids concentration. Efforts to eliminate deposition are described.

Jan 1, 1963

By Richard D. Miller

This publication contains routine analyses and related source data for 295 natural gas samples from 18 States collected during calendar year 1963 as part of a continuous survey of the United States for occurrences of helium in natural gas. This survey has been conducted by the Bureau of Mines since 1917. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4863/ and 576.4/

Jan 1, 1965

By Richard D. Miller

This publication contains routine analyses and related source data for 295 natural gas samples from 18 States collected during calendar year 1963 as part of a continuous survey of the United States for occurrences of helium in natural gas. This survey has been conducted by the Bureau of Mines since 1917. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4863/ and 576.4/

Jan 1, 1965

By W. D. Mcmillan

Although the Shafter district of Presidio County, Tex., is principally renowned for silver production from the Presidio mine, the occurrence of lead-zinc ores in the western part of the district has been known for at least 50 years, and there has been some production. An area of about 3 square miles in the vicinity of an extending westward from the Presidio mine was investigated in detail by C. P. Ross of the Federal Geological Survey in 1934. In the fall of 1943, A. B. Needham, an engineer of the Bureau of Mines, called the attention of the Geological Survey to the area west of that included in Ross's map, and requested a detailed investigation of that area by the Survey in advance of development by the Bureau of Mines. After a brief reconnaissance by the Survey in the spring of 1944, detailed studies were made by Federal geologists in the summer of 1944, during which about 450 acres were surveyed, on a scale of 1 inch to 100 feet. Recommendations for the exploration of certain parts of the area were made in the accompanying report.

Jan 1, 1949

By R. E. Campbell

Uranium metal of improved purity was prepared by electrorefining commercial magnesium-reduced uranium in a molten sodium chloride-uranium trichloride electrolyte. The best operating conditions for the preparation of refined metal were established as follows: an electrolyte containing 8.7 to 13.3 weight-percent uranium; initial cathode current densities from 300 to 1,500 amp/sq ft; and a molten salt temperature of 860° C. Ingots produced from electrorefined uranium crystals prepared with these operating conditions were substantially free of metallic impurities. The only impurities in the refined and consolidated metal were present in low or undetectable amounts.

Jan 1, 1965

By A. W. Khair, L. D. Gehl

"This paper describes the mechanism of coal and rock cutting from quasi-static indentation through dynamic indentation to rotary cutting. The results indicate that during quas~static indentation, a crushed zone, and subsurface fractures develop. The crushed zone is a potential source of dust generation. Dynamic indentation produces a crushed zone due to the frictional resistance offered by the coal or rock during penetration of the bit. Confining pressure changes the mode of failure from tension to mixed tension and shear. The wider bit causes larger crushed zone and more dust generation. The rotary cutting is a combination of quasi-static and dynamic indentation which results in chip formation. 1. INTRODUCTIONThe trend from conventional mining to continuous machine-cutting of coal, using more productive machinery is inexorable. Intolerable levels of dust generated at the face is an indication of inefficient coal or rock cutting by these machines. The Federal Government of the United States paid about 11.7 billion dollars workman compensation to more than 470,000 miners with Coal Workers Pneumoconiosis (Newmeyer, 1981). Bieniawski and Zipf (1985) reported that annual benefit payments were about 2 billion dollars. The need for research m improving coal cutting 1s therefore paramount. The enactment of Health and Safety Act in 1969 in the United States triggered the initial investigation into coal cutting mechanism and cutting tool design. The European countries were also engaged in the same area of research, however, their emphasis was in the use of wedge shaped bits. In 1981, the United States Bureau of Mines commissioned the South West Research Institute to investigate the effect of operating parameters mainly on airborne respirable dust in order to provide a healthier and safer atmosphere for coal mine workers.A research program by the Department of Mining Engineering, West Virginia University, USA was initiated to study the fragmentation mechanism during coal/ rock cutting. The research program was divided into three areas of research, namely quasi-static indentation, dynamic indentation and rotary cutting."

Dec 1, 1995

By S. J. Broderick

[The term "nonmetallic minerals? as commonly used is the mining industry, refers to those minerals of industrial importance that are mined essentially for uses other than for the metals contained. The field comprises several hundred rod minerals of industrial importance, of which 70 have can adequately described in the textbook Industrial Minerals and Rocks. A few o f the more important nonmetallic products are sand and gravel, salt, phosphates, clays, refractories, limestone, and cement materials. Some of the minerals, such as bauxite and pyrolusive, have both metallic and nonmetallic applications, but in this report only the nonmetallic mineral phases are considered. In the organic field of nonmetallics only coal is considered, as, the others - petroleum, natural gas, natural bitumens, and hydrocarbons - are of no importance in water softening.]

Jan 1, 1941

By W. H. Tomlinson

During the 9 years ended December 31, 1938, 188 fatalities resulted from preventable accidents in and around the coal mines of Indiana; 173 of these occurred at underground mines and 15 at stripping or open-cut operations. In addition, there may have been other unrecorded fatalities during this period. The two organizations receiving notice of accidental deaths at coal mines in this State are the Division of Mines and Mining and the Indiana Industrial Commission. Only deaths occurring at underground mines employing 10 or more men are reported to the former, as neither strip mines nor underground mines employing fewer than 10 men cone within the purview of the Indiana mining law. The mine inspectors have no Jurisdiction over this latter group of mines and do not inspect them. Fatalities at small "wagon" mines and open-cut operations are supposed to be reported to the Industrial Commission; however, in many instances deaths at small mines are not reported, the only record being a death certificate filed with the county or corporation health officer. Thus, many deaths in small mines escape attention, especially when the victim succumbs some time after the injury was received. The data presented here on fatalities in Indiana, during the past 5 years include several instances in which the only record available is a death certificate; possibly others have been overlooked. From 1934 to 1937 the fatality record was progressively worse, that of the larger underground mines in 1937 being more than twice the average for these mines for the previous 4 years and only slightly less than twice the average for all mines, including open-cut operations. The increase in deaths during 1937 was due to two explosions, with 20 fatalities in one and 2 in the other. The number of deaths in the larger underground mines was considerably less in 1938 than in the previous 4 years, but there was no improvement in the number of fatalities at the small mines, or at open-cut mines.

Jan 1, 1940