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By T. G. Joseph, M. Welz

ABSTRACT: Joseph (2002) introduced passive seismic monitoring to measure mining equipment performance. This paper evaluates the potential of passive seismic monitoring to correlate mining equipment operation with oil sands surface response, with a mining hauler as the seismic source. When applied to moving haulers, this action–reaction approach is complex. Vibrations from on-board equipment, such as pumps and tires, dirty the signal with noise. To facilitate any correlation, the signal must be cleaned up. Existing geophysical analytical techniques were manipulated to evaluate the noise problem and to filter sufficiently to permit an evaluation of whether a mining equipment action–ground response relationships in fact discernable.

Jan 1, 2011

By Michael G. Nelson, Sekhar Bhattacharyya

Between 1974 and 1977, a detailed study of coal pillar strength was conducted by the University of Utah at the Beehive mine in southeastern Utah. This study was funded by the U.S. Bureau of Mines, and included laboratory testing of coal samples, extensive field instrumentation and measurements, and finite element analyses based on the laboratory results. Recently, a similar analysis of the laboratory results and mine design geometry was completed using the LAMODEL program developed by NIOSH. The results of this analysis were close to the data collected in the field. This study allows comparison with the earlier finite-element analysis, and illustrates the utility of the LAMODEL software suite.

Jan 1, 2005

By Visnovsky

The computing needs of a mine planning office vary greatly depending on the staff available and the nature of the work undertaken. Some offices work acceptably with few aids apart from hand held calculators while others use mainframe computers with associated data bases and sophisticated mine planning software. Not every mine planning office requires the big system approach but all can benefit from the intelligent use of small computers. There is virtually no limit to the design problems which can be solved using modern desktop computers. The simple language required encourages engineers to work interactively to facilitate both large and small computations. However a limit does exist in the speed and ease with which solutions can be obtained. The important ingredients for the successful application of such machines are a little computing knowledge, a flexible machine, and an engineer who really understands the mining problems confronting him. If these are available it is possible for the engineer to tailor the program to the task at hand and efficiently achieve the required result.

Jan 1, 1983

By S.H. Ash, P.S. Miller

Extensive and diversified resources justify large populations and great industries. To carry on the business of commerce and meet the demands of large populations, the utilization of tunnels in some form for transportation purposes constitutes an important link in modern civilization. The driving of tunnels has been appropriated by the tunneling branch of the heavy-construction industry, and the progressive steps taken by modern tunnel builders were not even dreamed of 50 years ago. Great strides have been made toward more rapid progress in tunneling in the United States during the past I0 years. Tunneling consists of a definite cycle of operations developed from ideas that are crystallized and translated into action programs through various engineering phases that begin with the first preliminary survey and do not end until the job is completed. Once the line of the bore is established and a time set for the completion of the work, the face must advance according to estimates prepared before the work commences. This schedule must be followed in regular sequence from the moment the drills start against a new face of rock until they are ready again to drill the Succdeding face, constituting a round. Mining is largely tunneling carried on under conditions often more inherently hazardous than actual tunnel construction, but for various reasons" tunne1ing is more hazardous than mining in any branch of the mineral industry. On the other hand, obstacles are sometimes encountered in heavy-construction tunneling projects that when met in mining enterprises do not offer comparable tasks to avoid or overcome them. One is the existence of water under high pressures. In mining enterprises, various alternatives offer a solution in driving a tunnel, even to the extent of its discontinuance or the abandonment of the mine, but a "construction" tunnel usually must go forward because some important project depends largely if not entirely upon it. This paper describes an unusual method of driving a water-supply tunnel through rock carrying water under pressures and conditions that did not permit the use of ordinary tunneling methods. The Delaware Aqueduct The new Delaware aqueduct is a Manhattan project of some magnitude; when regular it will contain what probably will be, for some time to come, the longest tunnel in the world. Various features in its construction are currently described in the trade journals of the construction industry, and informative engineering details are given in the Delaware Water Supply News, published twice a month by the Board of Water Supply of the City of New York. Work was begun on this project on March 24, 1937. The tunnel will convey water from reservoirs at the headwaters of the Delaware River to the City of New York.

Jan 1, 1943

By P. S. Miller, S. H. Ash

Extensive and diversified resources justify large populations and great industries. To carry on the business of commerce and meet the demands of large populations, the utilization of tunnels in some form for transportation purposes constitutes an important link in modern civilization. The driving of tunnels has been appropriated by the tunneling branch of the heavy-construction industry, and the progressive steps taken by modern tunnel builders were not even dreamed of 50 years ago. Great strides have been made toward more rapid progress in tunneling in the United States during the past I0 years. Tunneling consists of a definite cycle of operations developed from ideas that are crystallized and translated into action programs through various engineering phases that begin with the first preliminary survey and do not end until the job is completed. Once the line of the bore is established and a time set for the completion of the work, the face must advance according to estimates prepared before the work commences. This schedule must be followed in regular sequence from the moment the drills start against a new face of rock until they are ready again to drill the Succdeding face, constituting a round. Mining is largely tunneling carried on under conditions often more inherently hazardous than actual tunnel construction, but for various reasons" tunne1ing is more hazardous than mining in any branch of the mineral industry. On the other hand, obstacles are sometimes encountered in heavy-construction tunneling projects that when met in mining enterprises do not offer comparable tasks to avoid or overcome them. One is the existence of water under high pressures. In mining enterprises, various alternatives offer a solution in driving a tunnel, even to the extent of its discontinuance or the abandonment of the mine, but a "construction" tunnel usually must go forward because some important project depends largely if not entirely upon it. This paper describes an unusual method of driving a water-supply tunnel through rock carrying water under pressures and conditions that did not permit the use of ordinary tunneling methods. The Delaware Aqueduct The new Delaware aqueduct is a Manhattan project of some magnitude; when regular it will contain what probably will be, for some time to come, the longest tunnel in the world. Various features in its construction are currently described in the trade journals of the construction industry, and informative engineering details are given in the Delaware Water Supply News, published twice a month by the Board of Water Supply of the City of New York. Work was begun on this project on March 24, 1937. The tunnel will convey water from reservoirs at the headwaters of the Delaware River to the City of New York.

Jan 1, 1943

By James G. Crawford

Correlation Of water with its reservoir zone or formation has been one of the applications of oil-field water analysis of greatest direct value to the petroleum engineer. The water in each producing zone tends to have diagnostic characteristics by which it can be distinguished from every other water above or below that zone in that immediate vicinity. Representative analyses of oil-field waters from producing oil and gas fields in the Rocky Mountain region are included, and the diagnostic characteristics are discussed briefly. It is concluded that the generally dilute nature of Rocky Mountain oilfield waters is a result of dilution by meteoric waters, and that there is no relationship between presence or absence of commercial oil and the character of water in a structure. Introduction The study of waters associated With oil and gas began more than 50 years ago and has been well recognized by operators, engineers, and geologists for about 30 years. It appears unnecessary at this time to recite the history of oil-field water analysis; suffice to say that it has proved its worth many times to the production engineer suddenly confronted with water problems in producing oil and gas wells. Chemists and geologists have studied the possible origin of these waters and as Yet the subject is unsolved in many important phases. There are both local and regional problems connected with the explanation of concentrations and character- istics peculiar to each field, each subsurface zone and each province. Criteria useful in postulating the Occurrence of oil Or gas in One province completely fail when applied to another, and data carefully prepared and analyzed from one field may be actually misleading when applied to another. Correlation of water with its reservoir zone or formation has been one of the applications of oil-field water analysis of greatest direct value to the engineer. The concentrations and characteristics of the waters are essential to the engineers and geologists making interpretations of electric logs in this region. The behavior of water under conditions of reservoir temperature and pressure is dependent to a great degree upon its concentration and characteristics, and thus important to the reservoir engineer. With the advent of secondary recovery methods in the Rocky Mountain region the characteristics and treatment of water will become increasingly important. Premises upon which Correlation Is Based A brief review of the geochemical history of oil-field waters will suffice to present the premises upon which correlations of the waters are based. Sedimentary rocks which are now stratified were first sediments in seas, lakes and streams. These sediments were filled interstitially with connate water. With burial the sediments were compressed arid consolidated, integrated and indurated into bed rock and much of the connate water was dispelled. Following the formation of bed rock the strata were sub-

Jan 1, 1949

By Carl H. Samans

The attention of physicists and metallurgists has been directed toward the study and explanation of the deformation textures in metals for the past 15 years. In 1920 N. Uspenski and S. Konobejewskil were first able to show that the symmetrical X-ray diffraction effects that had been previously reported by E. Hupka2 and others in metal foils were caused by a directed arrangement of the crystallites. Since then, the systematic study of textures resulting from the application of the pure forces of tension or compression to polycrystalline materials has been supplemented by many investigations on deformed single crystals, which have greatly added to our knowledge of deformation. However, despite the valuable information secured from these comparative studies only four investigations upon cold-rolled single crystals of any of the face-centered cubic metals have been reported in the literature. This lack of quantitative data is especially unfortunate because of the much greater practical significance of rolling textures and their effects in both cold-rolled and annealed materials. This investigation was undertaken for the purpose of specifying the deformation of rolled single crystals in the hope that such information might later facilitate the explanation of polycrystal-line textures. Of the four studies that have been made upon cold-rolled single crystals, only two are of any quantitative value. S. Tanaka,3 working

Jan 1, 1934

The progress of longhole open stoping (LHOS) at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited (ZC/NBHC) is described. The design of a novel sloped wall longhole stoping method at NBHC which should allow the cuplete extraction of the orebody without the formation of pillars and with minimal dilution of the ore with sandfill is reviewed.

Jan 1, 1983

Numbering of the Journal Because computer and library authorities prefer journal subscriptions to be based on the calendar year, and because the present numbering system of the Journal of the South African Institute of Mining and Metallurgy does not conform with the calendar year, it has been decided to change the numbering system of the Journal.

Jan 1, 1979

By J. E. Johnson

Discussion of the paper of Mark A. Amnion, presented at the Cleveland meeting October, 1913, and printed in Bulletin No. 70, October, 1913, pp. 1167 to 1 79. J. E. JOHNSON, JR., Ashland, Wis.:-Mr. Amnion's paper is of great value and it is not with any desire to reflect. on it that I wish to make some comments on the use of the scleroscope. We obtained one on trial some months ago and made very extensive tests with it, but without getting very satisfactory results. The readings on good car-wheels and bad ones were just about the same, but the factor in its use most likely to produce erroneous results is a variation in the thickness of the specimen being tested. In order to find out something on this subject we cut a thin disk, about -1,: in. thick, off a brass rod; then one 0.25 in. thick, and another about 1 in. thick, put the surfaces of all in about the same condition and tested them with the scleroscope. The readings varied widely; the resilience of the anvil evidently entered to a very high degree on thin pieces. By putting a soft cushion between such a thin specimen and the anvil, and forcing it up against the tube, the softness of the cushion cut off the resilience of the anvil and the results were more like those of the thick specimens. After a thickness of 1 in. was passed, the specimen seemed to have mass enough so that the resilience of the anvil no longer played an important part, and above that thickness results on different materials would be comparable, even though the thicknesses differed. But in order to get comparable results on thin specimens the thickness of those being tested should be the same. I should like to ask how the variations introduced in this way were overcome, so as to get strictly comparable results. Mr. AMMON :-.I have not had much experience in that, but the scleroscope is simply an indication of the surface harden-

Dec 1, 1912

Gravity concentration of tin at Renison Limited uses tables and spirals to treat the various coarser fractions produced from sulphide flotation tailing. An acceptable final tailing cannot be made from one pass over the tables and spirals and therefore the tailing from these separators is reground and combined with the sulphide flotation tailing as the feed to the classification section. The gravity section became increasingly overloaded in the years preceding 1976 due to efforts to maximize tin recovery to the gravity concentrate. In April, 1976, two 2DSV Reichert cone concentrators in series were installed to treat the table and spiral tail- ing stream, prior to regrind, to scavenge a small tonnage of hard, coarse low tin grade material for rejection to final tailing. Gravity section loadings were decreased markedly, allowing operator attention to be directed more to table performance than to spillage collection. An increase in mill throughput of approximately 15% was possible following the commissioning of the Reichert cones. The cones are currently operated to make the minimum tonnage of tailing consistent with reasonable- gravity section loadings.

Jan 1, 1978

By R. E. Reed-Hill, W. H. Hartt

High-purity magnesium single crystals, oriented with basal plane parallel to stress axis, were deformed in tension at room temperature so as to form second-order (1011)- (1012) twins. Investigation by optical and replica electron microscopy revealed that these twins can support very large internal strains approaching 1000 pct and that fracture follows as a direct consequence of these strains. At low strains the basal plane within (10i1)- (10i2) twins rotates with increasing deformation until it becomes approximately parallel to the twin boundaries. This rotation is not consistent with deformation by basal slip in the double twin, but may be rationalized in terms of nonbasal slip. Observations also indicate that basal slip in the primary (1011) twin, prior to second-order twinning, may contribute to this rotation. Deformation markings that are difficult to interpret in terms of slip on previously observed systems were noted in the twin bands. A possible means of rationalizing these markings is to relate them to grain boundary shear. The fracture associated with these twins is thought to initiate by formation of voids at the twin boundaries. These grow into microcracks, with ultimate fracture occurring by tearing of the interconnecting regions. THE significance of deformation and fracture along second-order (10i1)-(10i2) twins in polycrystalline magnesium1-' and many magnesium alloys4 was discussed in a previous paper.5 It was noted that this double twinning mode effectively controls the room-temperature deformation and fracture of magnesium single crystals, oriented with the basal plane parallel to the tensile axis. Reed-Hill and Robertson6 observed that, although these crystals may fracture at a macroscopic strain of less than 1 pct, shear strains up to 1000 pct could occur within (1011)- (10i2) twin bands. They concluded that the fracture was "ductile" and resulted from concentrating the deformation into a very small volume. The present research was undertaken to obtain a better understanding of the deformation and fracture associated with these twins. EXPERIMENTAL TECHNIQUES The experimental procedure involved straining high-purity magnesium single crystals in tension at room temperature. Specimens were oriented so that the applied stress direction was within 2 deg of the [1010] crystal axis. The specimen cross section was rectangular with faces closely parallel to (1210) and (0002). The specimen preparation and testing procedures have been described in detail elsewhere.5 Second-order (1011)- (1072) twins nucleated during straining were studied using optical and replica electron microscopy techniques. For the latter, cellulose acetate-carbon double replicas were employed. Observations were made on the (1210) crystal surface, which is the plane of shear for twins of this type. In addition to the single crystals, some investigations were carried out on longitudinal polycrystalline specimens. These were obtained from high-purity magnesium plate with a texture in which the basal planes of the grains tended to be nearly parallel to the specimen axis. All. polycrystalline specimens were annealed prior to testing in order to produce a coarse grain structure, permitting Laue back-reflection X-ray photographs to be obtained from grains of interest. EXPERIMENTAL RESULTS a) Deformation Within ( 101 l )-( 1072) Twins. Fig. 1 is an optical micrograph demonstrating the extent of the plastic deformation that can occur in (1011)-(10i2) twin bands. Notice at the lower left corner of the photograph the large displacement of the dark band (a polishing step) where it crosses the twins. The shear strain in the twin band at this position was computed to be 700 pct, using the ratio of step width to twin thickness. It was previously shown5 that (1011)- (1012) twin bands are often composed of small, separate twins aligned close to the macroscopic habit plane. Fig. 2 is an electron micrograph from near the upper end of the twin band in Fig. 1. This illustrates that the twin habit often does not coincide exactly with the macroscopic band habit, but may be inclined at a slightly smaller angle to the matrix basal plane. Figs. 3 through 6 are electron micrographs of the twin band in Fig. 2 illustrating successive steps in the development of deformation inside the band. A twin band such

Jan 1, 1969

Bauxite mine rehabilitation is an important stage of today’s bauxite mining activities. To get an overall picture on those activities the International Aluminum Institute (IAI) has been carrying out Bauxite Mine Rehabilitation Surveys since 1991. The most recent survey from 2003 covers 70% of the world’s bauxite production and 23 corresponding companies from 12 countries. The survey activities show that nearly all operations refer to a sophisticated environmental management strategy. By setting up a review scheme based on the principles of the Global Reporting Initiative the compliance of this survey to aspects of Sustainable Development has been reviewed. The Clarification of a multitude of aspects based on the GRI guidelines helped to structure recommendations and relate them to the survey as such but also to the different stakeholders involved.

Jan 1, 2005

A brief review of the problems in ventilating and cooling deep and hot Australian mines is presented. An overview is given on the development of the controlled partial recirculation concept. The main part of this paper describes the first majo

Jan 1, 1994

By J. R. Stack, H. H. Alexander

Prior to 1915, numerous attempts were made to treat tin concentrates in the United States, but for various reasons they were unsuccessful. Tin ore is said to have been found in nearly every state, but none of the deposits has proved to be of commercial importance. An annual output of a few hundred tons in Alaska is the only domestic production; hence any considerable production of tin in the United States must be from foreign ores. The most promising occurrence of tin was found in the Black Hills, S. Dak.; in the early development stage, it was called the Cornwall of America. Associated with the tin is tungsten The story is told that an exceedingly fine specimen of the Black Hills ore was sent to England to encourage stock promotion; the desired effect was produced until a skeptic chipped off a small piece, which the analysis showed to be wolframite. First Attempts at Smelting One of the first promising attempts at tin smelting in the United States was made by R. T. White at Bayonne, N. J., in 1903. Mr. White, after spending some time in England studying the methods of tin smelting, organized a company called the International Tin Co., and erected a plant to treat tin concentrates from the Straits of Malacca. About the time the plant was completed, the English Government placed an export duty of 40 per cent. ad valorem on tin concentrates exported to other than British smelters, which duty made it impossible to operate this plant so the enterprise was abandoned, As this export duty is still effective, the only source of tin-ore supply for the United States is the Bolivian concentrates. Bolivian Tin Concentrates Unlike the alluvial placer deposits, nearly all Bolivian tin occurs in lode deposits and some of the highest grade ores contain only a small

Jan 1, 1924

By Diana Pérez Escobar

O efeito do caminho de solidificação de um aço High Temperature Processing (HTP) API 5L X65 com 0,09 %Nb, 0,039%C e 0,54% Mn (percentagem em massa) na segregação, microestrutura e distribuição dos precipitados de Ti,Nb(C,N) foi estudado por microscopia ótica, eletrônica de varredura (MEV) e simulação computacional (ThermoCalc e DICTRA). Os resultados foram comparados com os de um aço microligado comercial com 0,04 %Nb, 0,09%C e 0,97 %Mn. Foi encontrado que o principal parâmetro que influencia no caminho de solidificação é o teor de C, o que está de acordo com a maior micro e macrossegregação observada no aço microligado comercial, em comparação ao aço HTP.

Oct 30, 2017

By Wayne A. McCurdy

For the third consecutive year, predicted increases in coal production and consumption failed to materialize. Production of bituminous, sub-bituminous and lignite coal for 1961 was estimated by the U.S. Bureau of Mines at 400 million tons, a drop of 15,- 512,000 tons from the 1960 figure. Anthracite production for the year was 17.8 million tons compared to 18.8 million tons produced in 1960. Consumption figures are expected to show a proportionate decline. Of coal's major markets, only electric utilities showed an increase-and even here the increase of approximately 2% was smaller than had been expected. Major cause of relatively low consumption was a decrease of more than 20% in the use of metallurgical coal for making coke. Reductions of lesser importance were registered in general industrial, retail, and export markets.

Jan 2, 1962

By Jerry Newton

The bulk explosives industry is relatively young compared to how long explosives have been in use. It's been around for about forty years, about the length of a person's career. This period of explosives history has seen constant change. The type of product, the manufacture and the trucks that haul it have changed a great deal over the years.

Jan 1, 1997

By H. A. Schwartz, Wolfram Ruff

The spheroidal form of the temper carbon nodules in malleable cast iron and of the graphite mottles of "mottled" cast iron suggests that in both all the graphite in a given mottle or nodule grew from a single center of crystallization or nucleus. $ There is, however, a distinct metallo-graphic difference between the mottle and the nodule; the area of mother metal impoverished in combined carbon by the crystallization of graphite in a mottle is practically coextensive with the ramifications of the graphite, while the impoverished zone of metal corresponding to a given nodule is always larger, and usually much larger, than the approximately spherical mass of graphite crystals forming the nodules. Furthermore, the mottle probably is formed during freezing and the nodule almost always at a considerably lower temperature. Assuming that the nodules or mottles can be used as a measure of the existing nuclei (capable of germination) we propose to record certain observations as to the graphitizing reaction in the light of the number and habits of growth of these nuclei. The present authors, in cooperation with others'-', have reported upon various cognate aspects of the problem. The fact that temper carbon is a mass of flakes and not a solid granule has become well recognized since the introduction of an improved polishing technique8, 9, 10 for cast iron. The problem of deriving from the circular planar intercepts of a mass of spheres of varying sizes their number and size distribution in space has also been satisfactorily solved12, 13 Growth of Nuclei in White Cast Iron It has already been shown1, 3 that the progress of graphitization with time is usual1y consistent with the assumption that nodules grow in size

Jan 1, 1936

By Wolfram Ruff, H. A. Schwartz

The spheroidal form of the temper carbon nodules in malleable cast iron and of the graphite mottles of "mottled" cast iron suggests that in both all the graphite in a given mottle or nodule grew from a single center of crystallization or nucleus. $ There is, however, a distinct metallo-graphic difference between the mottle and the nodule; the area of mother metal impoverished in combined carbon by the crystallization of graphite in a mottle is practically coextensive with the ramifications of the graphite, while the impoverished zone of metal corresponding to a given nodule is always larger, and usually much larger, than the approximately spherical mass of graphite crystals forming the nodules. Furthermore, the mottle probably is formed during freezing and the nodule almost always at a considerably lower temperature. Assuming that the nodules or mottles can be used as a measure of the existing nuclei (capable of germination) we propose to record certain observations as to the graphitizing reaction in the light of the number and habits of growth of these nuclei. The present authors, in cooperation with others'-', have reported upon various cognate aspects of the problem. The fact that temper carbon is a mass of flakes and not a solid granule has become well recognized since the introduction of an improved polishing technique8, 9, 10 for cast iron. The problem of deriving from the circular planar intercepts of a mass of spheres of varying sizes their number and size distribution in space has also been satisfactorily solved12, 13 Growth of Nuclei in White Cast Iron It has already been shown1, 3 that the progress of graphitization with time is usual1y consistent with the assumption that nodules grow in size

Jan 1, 1936