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By Thomas G. Murdock

The possible contribution of an improved mineral economy to the further advancement of the lesser developed regions of the world is a vital consideration today. Many of the newly independent countries recognize the problems and the challenge involved in orderly development of mineral resources. Some countries are inventorying resources, planning development, and encouraging local and foreign participation. The Malagasy Republic, composed of the island of Madagascar and the immediately adjacent islands, formerly the French Overseas Territory of Madagascar, is one of the members of the French Community which achieved independence in 1960. It is making real progress towards improving its mineral economy, an effort particularly remarkable considering the generally unfavorable geographic location of the area with respect to world markets and what is, after all, a comparatively sparse economic mineralization in the light of discoveries to date. Most of the development of the Malagasy econorny before independence was fostered by French private enterprise, although the State participated in some ventures. Since independence, the Government has encouraged private investment from a variety of sources through favorable legislation and has indicated that legitimate investment projects that will further advance social and economic programs will be welcome.

Jan 1, 1963

By Thomas G. Murdock

The possible contribution of an improved mineral economy to the further advancement of the lesser developed regions of the world is a vital consideration today. Many of the newly independent countries recognize the problems and the challenge involved in orderly development of mineral resources. Some countries are inventorying resources, planning development, and encouraging local and foreign participation. The Malagasy Republic, composed of the island of Madagascar and the immediately adjacent islands, formerly the French Overseas Territory of Madagascar, is one of the members of the French Community which achieved independence in 1960. It is making real progress towards improving its mineral economy, an effort particularly remarkable considering the generally unfavorable geographic location of the area with respect to world markets and what is, after all, a comparatively sparse-economic mineralization in the light of discoveries to date. Most of the development of the Malagasy economy before independence was fostered by French private enterprise, although the State participated in some ventures. Since independence, the Government has encouraged private investment from a variety of sources through favorable legislation and has indicated that legitimate investment projects that will further advance social and economic programs will be welcome.

Jan 1, 1963

By John H. Johnson

White Pine Mine section designated for exhaust emissions studies. The MTU Mine Air Monitoring Laboratory was used to gather temperature and C02 concentration data at 10 locations. The data substantiate the presence of strong buoyant forces of the hot exhaust gases which result in stratification in dead end headings. Diesel mine-vehicle tailpipe emissions were monitored in the laboratory by a portable tailpipe emissions measurement apparatus (EMA) assembled for in-mine use. The results were compared with simultaneous measurements by standard laboratory exhaust monitoring instruments. These results indicate that accurate field source quality control measurements can be obtained for CO2, CO and NO but NO2 results were low for all engine conditions. Diesel pollutant concentration data from the Orchard Valley Mine were analyzed and compared with data collected earlier in the White Pine and Brushy Creek mines. Lognormal frequency distributions and CO2-based concentration ratios and correlations were calculated. In the three mines compared, pollutant concentrations were distributed similarly, and concentrations appear to be controlled to present standards.

Jan 1, 1979

By Sidney Katell

This report, covering the period January 1969 through December 1969, is a continuation of a series that began with the publication of Information Circular 7516 in October 1949. It is the 11th in a series of reports prepared in cooperation with the American Association of Cost Engineers. The abstracted articles are concerned with all phases of cost engineering in the field of chemical and petroleum plants and related subjects. They are from the following sources: 1. American Association of Cost. Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress. 6. Chemical Week. 7. Coal Age. 8. Coal Mining and Processing.

Jan 1, 1970

By Albert L. Toenges

[sing tho ppsf; few Yomn t!le:.c. hcs beer. p. trqnd away frorn locomotive haulwe of cop2 frorn tile losdiw point to tho prop,nration plant of bitu~i- nnus-cod strip mlncc to a;~to~lzcd. h,71Jlr.:~. The qrostion has arisen rrhethcr this is alwqvs econ~nicd, rxcl the purpcrse or' tnf s investigation is to de- termine, if possible, the econonic limlt for ~~torieod had.we. sing tho ppsf; few Yomn t!le:.c. hcs beer. p. trqnd away frorn locomotive haulwe of cop2 frorn tile losdiw point to tho prop,nration plant of bitu~i- nnus-cod strip mlncc to a;~to~lzcd. h,71Jlr.:~. The qrostion has arisen rrhethcr this is alwqvs econ~nicd, rxcl the purpcrse or' tnf s investigation is to de- termine, if possible, the econonic limlt for ~~torieod had.we.]

Jan 1, 1938

By T. M. Barczak

The term "resultant load vector" is defined as the representation of the forces applied to a longwall roof support element by strata activity through a single, quantifiable measure of support resistance. The relatively complex kinematics of the shield structure prohibits determination of support resistance simply from the summation of leg forces. In the research reported in this Bureau of Mines study, the mechanics of the shield structure were evaluated, and a technique was developed whereby the resultant shield loading could be determined by instrumenting supports with pressure transducers and strain gauges to measure leg, canopy capsule, and lemniscate link forces. This technique has been laboratory tested in the Bureau's Mine Roof Simulator. Functional relationships among variables were assessed, and confidence intervals were established for prediction of the resultant load vector parameters. Resultant load measurements were taken on five instrumented shields on an active longwall face in Colorado. Results were analyzed and found to be consistent with shield mechanics and anticipated roof behavior. Benefits to be derived from this research, future efforts, and long-range goals are discussed.

Jan 1, 1986

By E. O. Binyone

"https://www.youtube.com/watch?v=PBPyGXjlBHIhttps://www.youtube.com/watch?v=3AbtiKOYg7Y&feature=push-fr&attr_tag=uKtVW3yq2ZngptnE%3A6https://www.youtube.com/watch?v=PR2THayf-N8https://www.youtube.com/watch?v=mF-BXiWocqIhttps://www.youtube.com/watch?v=TuesIw-OZA4https://www.youtube.com/watch?v=v2HP7sTIZgEhttps://www.youtube.com/watch?v=v2HP7sTIZgEINTRODUCTIONIn 1937 the Eureka Corporation, Ltd., of Canada obtained a lease on the mining property of the Richmond-Euroka Mining Co. in the Eureka mining district, Eureka County, Nevada. In 1910 the Richmond-Eureka Co. suspended all operations except small-scale leasing, but company and other geologists contended that the El Dorado dolomite would also carry ore in its continuation from fault block north and northeast of the productive old working. The company began to explore the fault block in 1923 by diamond drilling from the,900 level of the Locan shaft, but for various reasons the hole was drilled to a depth of only 2 feet and was then abandoned. Eureka Corporation, Ltd., planned an extensive diamond-drilling program, which included four deep diamond-drill holes, one designated ""A"" fig. if it is to be drilled from the surfaced, and three designated ""E"", ""C"" and ""D"" figs land to be drilled from the 900 level of the Locan shaft. Of these only B and C were completed by the company. Hole C was a contribution,of the hole started by the, started by the Richmond Eureka Co. The site for hole D (figs. 1 and 2) was prepared, but the hole was not drilled. Both B and C holes penetrated sulfide ore carrying good percentages of zinc, lead, gold, and silver. The ore bodies were 40 feet thick and were found approximately 1,400 feet below the 900 level of Locan shaft.On the basis of the very favorable results obtained from the drilling program, the Eureka Corporation planned extensive development of the property and in 1942 commenced sinking the Fad shaft (figs. 1 and 2). The shortage of equipment and materials brought on by the war and difficulties with water in the shaft greatly hindered progress. However, early in 1943 the Eureka Cor¬poration, Ltd., of Canada submitted to the War Production Board a proposal for developing the mine and milling 500 tons of zinc-lead ore a day. The proposal involved an expenditure of $2,890,750."

Dec 1, 1946

By D. W. Dareing

Multiple branch wellbores and horizontal holes, when applied to deep lying ore bodies, have the potential of significantly reducing well costs by reducing total footage drilled per acre of well pattern. In addition, horizontal holes may increase sweep efficiency. Well completion is a major problem. They must be cased to contain leaching solutions within the underground portion of the production loop. Several drilling and completion concepts are given and evaluated in the report. Our evaluation shows that there is economic incentive to further develop these concepts for field application to ore bodies 1,500 feet. Multiple branch concepts are the most attractive. They can reduce well costs by as much as 30° when applied to 2,000 feet ore body depths (44%, at 5,000 feet) and can accommodate a lamer pump than conventional vertical wells. We recommend this concept be developed further to accommodate either dual or triple branches.

Jan 1, 1980

By S. H. E. Phillips

This report describes the initial feasibility, the development and the field demonstration of a system for shaft sinking employing a high energy mechanical impact rock breaker and a compatible muck disposal system. The increased shaft sinking rates, decreased costs and improved safety conditions obtainable by the elimination of the less efficient conventional drill-blast-muck cycles are discussed. Four shaft sinking concepts utilizing the impact rock breaker in various shaft configurations are developed and the field demonstration in a rectangular shaft is described. The progress achieved, the problems and their remedies and the proposed modifications to improve the machine are described.

Jan 1, 1978

By T. F. Mitchell, J. V. Batty, R. R. Wells, R. Havens

"INTRODUCTION )ne of the most important wartime activities of the Bureau of Mines was the search for new sources of minerals necessary to the prosecution of the war. As a part of the investigation of strategic mineral deposits in the United States under the Strategic Minerals Act (Public 117, 76th Cong., 1st Sess., Ch. 190), examining engineers of the Bureau of Mines investigated and sampled various deposits of chrome ore in California, Idaho, Montana, Oregon, and Washington, and those deposits that warranted further study were explored by diamond drilling, trenching, and drifting, as re¬quired. During these investigations, samples were submitted to the Ore Dressing Section of the Salt Lake City Station for metallurgical testing. This paper gives data summarizing results obtained from laboratory ore-dressing studies of the chrome ores submitted.Although the deposits range widely in geographical location, the mineral occurrence of all of them is strikingly similar. Chromium, in all of the ores tested, is present as impure chromite or chromium spinel. Although pure chromite (FeCr204 or FeO.Cr203) contains 68 percent chromic oxide, the iron may be replaced in varying amounts of magnesium, and the chromium may be replaced similarly by aluminum and ferric iron. In studying concentration methods as applied to chrome ores, the composition of the chrome mineral is of fundamental importance, because it is manifestly impossible to produce a high-chrome concentrate from a low-chrome chromite by any mechanical process.In all but one of the ores, the gangue material consists of olivine or altered olivine minerals such as serpentine, antigorite, and chrysotile. The exception, the Antelope or from Montana, has a gangue chiefly composed of actinolite, chlorite, and talc."

Jun 1, 1947

By H. S. Auvil

[Coals of low-volatile rank cannot be coked without admixing large proportions of high-volatile coal in the usual type of byproduct-coke oven, because they expand excessively and exert side thrust, which ruins the oven walls. Some medium-volatile coals also give trouble. Since high-rank coals produce a strong, blocky coke, it is desirable to have the rank as high as practicable, particularly in the manufacture of foundry coke. Accordingly, it has become the practice to mix or blend high-volatile shrinking, coals with as much low-volatile coal as possible and still have a mixture that will not deform the walls or cause difficulty in pushing the coke. Occasionally, the safe limit of low-volatile coal has been exceeded and ovens have been damaged. It is desirable, therefore, to rave a reliable method of determining the expanding tendencies of mixtures before they are charged into the ovens. Furthermore, coal charges somewhat in its properties as mining progresses, and therefore, mixtures found to be safe at one time may cease to be so subsequently, particularly if nearly the maximum allowable percentage of low-volatile coal is being used.]

Jan 1, 1938

By A. B. Needham

A number of the pegmatites in the southern Black Hills of western South Dakota contain sheet mica; and as the demand increased during World War II the area became an important producer of strategic qualities of mica. During this period of maximum activity, the U. S.. Geological Survey made detailed studies of the geological structural control, the mineralogical associations, and the production Of many pegmatites in the Black Hills. On the basis of results of this study, and at the suggestion of the Geological Survey, several of the pegmatites were examined by the Bureau of Mines, and a few were selected for further investigation. Accordingly, the White Bear, Silver Dollar, Buster Dike, and Hot Shot mines were diamond-core-drilled in 1947. The Hot Shot mine was investigated further by deepening the shaft and crosscutting the pegmatite in 1948. The mica-bearing deposits occur in lenticular intrusions of pegmatite in schists of various mineral composition. Eleven diamond-drill holes, totaling 2,111.4 feet in length, were completed on the four deposits. The shaft on the Hot Shot deposit was deepened 44 feet to the 112-foot level, and crosscuts were driven from the bottom of the shaft to the hanging Wall and foot wall of the pegmatite. This publication briefly describes the location, ownership, and history of the deposits and gives details of the work done by the Bureau of Mines and the Geological Survey.

Jan 1, 1950

By A. C. Burr

This progress report covers the period from January 1949 to the end of the fiscal year, June 30, 1950. Three runs were successfully completed, and one run was terminated as the result of failure of a cast reaction tube. Including the abbreviated run, the gasifier was operated for 1,915 hours, during which some 428 tons of natural and steam- dried lignite was partly gasified In producing 20 million cubic feet of gas. Gas-production rates varied from 7.8 to 16.4 thousand cubic feet per hour, the latter being the highest production rate yet reached; hydrogen-carbon monoxide ratios of the product gas varied from 1.85, the lowest ratio yet produced, to 6.5; and heat-transfer rates through the heated wall of the outer tube varied from 2,100 to 4,400 B.t.u. per square foot an hour. The general objective of the project is to establish the technology and economy of the gasification of lignite in an externally heated, metal, annular retort. Specific objectives include determination of the useful life of the metal retort tube, which is a continuing problem, and special objectives that were established for each run as part of the systematic investigation of the basic variables of the gasification process. For runs 10 and 11 the special objective was the influence of the lignite feed rate on gasification; for run 12, a comparison of dried and natural lignite, and the production of gas having a hydrogen-carbon monoxide ratio less than 2; and for run 13, the influence of a gradually increasing steam rate with steam admitted to either the upper or lower reaction zones. In addition, during each run the sulfur distribution and concentration in the product gas and char were investigated. Experimental results obtained using the lignite feed rate as the variable indicated that the gas yield per ton of natural lignite varied inversely with the feed rate. Comparison of the gasification of natural and steam-dried Dakota Star lignite indicated that the dried lignite was a superior gasification material because: 1. The hourly gas production was higher at normal combustion space temperatures under nearly equal experimental conditions. 2. On the moisture- and ash-free basis, a considerably higher feed rate could be maintained at a relatively high percentage of carbon gasified. 3. At nearly equal moisture- and ash-free feed rates, the specific gas yield was higher. The location of steam admission was found to be important because the gas yield per ton of natural lignite was higher when at least a portion of' the process steam was admitted to the upper reaction zone. Heat balances showed the potential heat in the gas and char to be 71.8 to 83.6 percent of the total heat input. The sulfur concentration in the product gas was low, being in the range of 35 to 140 grains per 100 cu. ft., of which 1.5 to 2.3 grains was organic sulfur. Careful measurements and inspection of the 310-alloy rolled plate tube following runs 11, 12, and 13 showed no excessive corrosion; however, some radial deformation had occurred indicating that deformation or creep might be the limiting factor in the life of the tube.

Jan 1, 1953

By Frank C. Morris

It is generally recognized that the productivity and ultimate recovery of an oil well may be reduced as a result of reduction in permeability of the sand at the well bore by invasion of filtrates and clay particles from drilling fluids. As a means of determining whether a sand has been "damaged" from these sources, several investigators2 3 4 5/ have developed methods of analysis based on the rate of increase in bottom-hole pressure while a well is shut in. Because of growing recognition of the importance of completion practices as related to the quantity of oil that may be recovered from wells, the Bureau of Mines has studied completion practices in California and the Midcontinent area. Well-interference and pressure-buildup tests were completed Ear seven wells in the Scurry Reef field to determine the effective permeability in the reservoir.6/ Also, a study was made of the pressure-decline curves obtained from 35 water-input wells in 5 different production areas of northeastern Oklahoma and eastern Kansas.7/

Jan 1, 1957

By Martyn F. Roetter

The objectives of the work described in this report are to determine the communications requirements and need for communications, both for voice and control, on longwalls, and to make recommendations for longwall communications equipment and systems. These recommendations are designed to guide the future development of longwall communications. Information necessary for the accomplishment of this work has been gathered by a series of visits to longwall mines and discussions with longwall mine operators, as well as with suppliers of longwall communications and mining equipment and with Bureau of Mines personnel. In addition, it has proven possible, through personal interviews and literature evaluation, to gain an understanding of the experience and attitudes towards longwall communications in countries where longwall mining is far more widespread than in the U.S., namely the Federal Republic of Germany, the United Kingdom, France and Belgium.

Jan 1, 1976

By D. Randolph Berry

Foster-Miller Associates has developed a set of guidelines to permit hoist manufacturers, mine owners, and MESA mine inspectors to design, purchase, install or inspect a safe and effective Emergency Escape Hoist, as required by the Coal Mine Health and Safety act of 1969. A series of surveys were carried out to determine: 1. The attitudes and local needs of the MESA District Managers. 2. Current escape hoist installations. 3. Equipment available for future designs. 4. Foreign methods and equipment for mine rescue. From these survey studies, preliminary guideline objectives were developed.

Jan 1, 2012

By Frederick W. Horton

The lack of comparable and accurate statistics of coal-mine accidents in the United States as a whole led the Bureau of Mines in 1911 to undertake the collection of such data. The importance of such statistics as a basis for remedial legislation can not be overestimated, moreover they serve to indicate the results of the efforts made by the Federal Government, State mining departments, and mine operators throughout the country to lessen the hazard of coal mining. The mining departments of the leading foreign coal-producing countries have long taken cognizance of the importance of such statistics. In Great Britain, official statistics of coal-mine accidents have been collected and published since 1851, in France since 1853, in Austria since 1875, in Germany since 1852, and in Belgium since 1831. The United States not only leads these countries in the production of coal but the output of its coal mines is greater than those of Great Britain, France, Belgium, Austria, India, Japan, and New South Wales combined. Accordingly, it is proper that there should be some official record of the accidents in this, the greatest mining industry not only in the United States but in the world. It is especially appropriate that this work should have been undertaken by the Bureau of Mines, as, through its investigations of mine accidents in the field, it is constantly in close touch with coalmining conditions throughout the country. Its engineers are not only able to obtain first-hand information as to a great many accidents, but, through their special training and experience, are able to appreciate the significance of the figures reported by the coal-mine operators, thus aiding an intelligent and uniform classification 01 the accidents for the country as a whole. Further, the State mining dnpartments and State mine inspectors of every State in the country having a system of coal-mine inspection are cooperating with the bureau by sending it monthly reports of accidents in the coal mines of their respective States. The receipt of such reports places the bureau in a most advantageous position to publish promptly statistics of these accidents. Although a few years ago accurate statistics of c~al-mine accidents in the United States as a whole were entirely lacking this bureau was able to pubjiish the 1912 statistics within three n:onths after the close of the year and long before corresponding statistics had been issued by the mining departments of the leading foreign coal-producing countries. The cooperative agreement with the State coal-mine inspectors has not only made possible the prompt publication of the statistics, but it has also enabled the bureau to classify the fatalities by months and according to cause, showing the months in which the greatest and the least number of men were killed and from what causessomething that has never before been accomplished for this country.

Jan 1, 1913

By James R. Boyle

The value of mineral production increased 6.2% in 1976. With the exception of coal, practically all commodities registered an increase in production and value; most had an increase in unit value. Total value exceeded $1 billion for the first time. The increase in nearly all nonmetallic mineral production was a complete reversal of the 1975 experience. Alabama led the Nation in the production of crushed marble and was second in bauxite and scrap mica, third in oystershell, third in kaolin, and fifth in dimension limes-tone and dimension marble. International Trade.-The international trade passing through the Mobile customs district was valued at $2,524 minion in fiscal year 1976, up 20% from that of the previous year. Of the total value of trade passing through the district, 52% of the value of experts and 89% of the value of imports were handled through the port at Mobile. The major export Commodity was coal through McDuffie Coal Terminal which amounted to nearly 2.9 million tons, up from 2.4 million tons in 1975. Coal exports were to Japan, Italy, Turkey, the United Kingdom, and Brazil. Other exports were cement (114,000 tons) and [ ]

Jan 1, 1979

By N. H. Darton

This report presents the results of an investigation begun by the Government in the summer of 1907, the investigation being started under the immediate supervision of Dr. J. A. Holmes and continued under him as director after it was transferred to the Bureau of Mines in 1910, the field studies being completed in the spring of 1912. The purpose of the investigation was to obtain information on the origin of the inflammable gases in coal and the conditions under which they occur. It was especially intended to ascertain whether there was any relation between the occurrence of gas and the structural or other geologic features of the coal beds. To this end many months were spent in mines and much time was devoted to the examination of mine maps, bore-hole records, and other data made available by the kindness of various coal companies. Two fields of work were selected-one in the northern anthracite basin of Pennsylvania, where the beds are considerably flexed, and the other in the southern part of the bituminous coal field of Illinois, where the beds lie nearly horizontal. In order to take advantage of results of previous investigations of the same general subject, an extended examination was made of reports of various investigators in Europe and America. A digest of the information obtained from these publications is included in the first part of this report, which constitutes an introduction to the discussion of the conditions governing the occurrence of inflammable gas in coal beds.

Jan 1, 1915

By R. Lusignea

This report describes the development of a device for the nondestructive testing of resin grouted roof bolts by means of mechanical frequency response. Various alternative methods were evaluated and the mechanical frequency response method was selected. An interactive program of design, testing, and development culminating in the current prototype instrument demonstrated the capabilities of the method and suggested potential applications of the instrument. The resin bolt testing device utilizes a swept frequency dynamic compliance measurement in the 1 to 2 kHz range which is interpreted by an electronic signal processor to give a "GO" or "NO GO? readout. Field tests have shown that the device can reliably determine the bond quality of the front half of the bolt (nearest the roof surface). Tests were carried out on both experimentally installed bolts and typical mine bolts installed by a conventional bolting machine. The development program has led to recommendations for improvement of the prototype and future development work.

Jan 1, 1979