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By John E. Callahan

"A stream sediment geochemical survey covering an area of 13.000 sq. km near Churchill Falls. Labrador. was conducted for Brinex (British Newfoundland Explorations Ltd.) prior to partial flooding by the Churchill Falls power project. Stream sediments (minus 80-mesh) were analyzed for Cu, Pb, Zn, Ni, Ag, Mo. U and Mn, and the heavy mineral, nonmagnetic fraction (minus 60-mesh) for Cu, Pb, Zn, Ni, Ag, Mo, Ba and Mn. A binocular examination of the concentrates for sulphides and pyrope garnet was done on the heavy mineral concentrates. The concentrates were also examined for fluorescent minerals.Two distinct areas with high trace-element values indicate the need for follow-up studies. The first is in an area of gabbro erratics containing massive and disseminated sulphides (pyrrhotite, pyrite and minor chalcopyrite) on the western edge of the survey area along the Esker Road. The second, largest area (several hundred square kilometres) is anomalous in U and Mo and associated with felsic intrusives (Red Wine Complex?), syenites. granite gneiss and sedimentary rocks (Seal Lake Group?).The binocular study showed that almost 15% of the heavy mineral concentrates contained pyrite and no other sulphides. This indicates that this technique may be worthwhile in determining the presence of sulphide minerals in stream sediments from glaciated environments. The only fluorescent mineral observed in the study was zircon."

Jan 1, 1981

By B. Stimpson, K. Kosar, K. Barron

"A number of high wall failures have occurred in some of the Alberta coal strip mines of a type called by the authors ""Multiple block plane shear slope failure "". They cause rapid deterioration of the dragline bench, reduced productivity and maintenance costs.The failures are invariably associated with the presence of almost horizontal (± 5 degrees) bentonitic clay bands in the overburden, often immediately above the coal seam, and regress behind the slope as a series of tension cracks which isolate detached blocks. As many as 17 sets of cracks have been observed, at lateral distances in excess of five times the slope height from the toe.The theory of this mode of failure is presented and a limiting equilibrium computer program which will produce deterministic or probabilistic (Monte Carlo) solutions is briefly described. A case history of one such failure is documented. It is shown that the extent of the regressive failure is exceedingly sensitive to the water table elevation, leading to the conclusion that drainage, if practical, represents the best control strategy. IntroductionA number of high wall slope failures are occurring in some of the coal strip mines in Alberta of a type called by the authors ""Multiple block plane shear slope failure""(I). These failures cause a rapid deterioration of the bench from which the dragline operates, reduced productivity, and necessitate conregresses into the slope as a series of tension cracks and detached blocks. As many as 17 prominent cracks or crack zones have been observed, the last being in excess of five times the slope height distant from the toe.The block between each pair of cracks must be at limiting equilibrium, i.e. the factor of safety equals one. This condition can be used to determine the locations of the cracks which develop in sequence behind the face."

Jan 1, 1986

By M. A. Mahtab, T. M. Yegulalp

This paper presents the development and application of an approach for clustering fracture orientation data. Data are projected on the surface of the unit upper hemisphere and the clustering approach is applied in three steps: (1) randomness test and identification of dense clusters, (2) estimation of cluster statistics, using Bingham distribution, and (3) rejection of extremal data based on Chauvenet's criterion.

Jan 1, 1982

By Gaulton R

The Commission maintains a data base first computerised in 1957 and containing information from over 18 000 boreholes located mainly in the Latrobe Valley area. Some of the borehole derived information dates from the turn of the century, although most of it has been collected as a result of Commission investigations conducted over the past 40 years. The Resource Data Base contains not only information gained directly from the drilling itself but includes the results of chemical and physical testing on many hundreds of thousands of samples retrieved from boreholes. Replacement value of the Resource Data Base has been estimated to be around $200 million, and it's integrity and accessibility is clearly of paramount importance, not only to existing mining and power generating functions but to the future evaluation and use of the vast brown coal Resource.

Jan 1, 1992

By Rashid Bashir

The presence of groundwater in the form of large aquifers can have an important influence on investment decisions for underground mines. The design for such mines requires development of special mining methods, and mine dewatering infrastructure to avoid hazards during shaft sinking and underground development. The costs associated with mine drainage control and Mine Dewatering Systems (MDS) are relatively small compared to the huge consequential losses that can occur in case of an uncontrolled inflow and subsequent flooding of the mine. The design of MDS needs consideration of accurate prediction of the maximum uncontrolled inflow rate, availability of the system during an uncontrolled inflow while the inflow is mitigated, and decision on pumping system technology to have capability to operate under water. The research presented in this paper provides a theoretical framework for a reliability based design procedure which takes into account the uncertainty in the estimate of the maximum uncontrolled inflow, performance of the system during the period of an uncontrolled inflow and a methodology to decide on appropriate pumping technology considering the reliability of the system and available underground storage. The reliability based mine design procedure integrates the ideas of Effective Reserve and Hydraulic Reliability Index to come up with a unified methodology for design of Mine Dewatering Systems.

Aug 1, 2010

By A Roudnev, P Loderer

Mineral froth pumping utilising centrifugal slurry pumps is a major engineering challenge for both the end users and pump manufacturers. The traditional approach has been to oversize the pump for pumping mineral froth. New horizontal slurry froth pump designs offer opportunities to improve froth pumping capability of mineral froth with challenging (high) Froth Volume Factor while maintaining high efficiency, long wear life and stable pumping performance.CITATION:Loderer, P and Roudnev, A, 2018. A reliable solution for pumping mineral froth with challenging froth volume, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 291–296 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By James E. York

AT a meeting of the American Society for Testing Materials at Atlantic City, June, 1908, Dr.. C. B. Dudley, in his presidential address,' showed the vital necessity of not only making a steel rail as good as in the past, but of making it considerably better in order to meet the present and prospective require¬ments of railroads. Doctor Dudley requested the co-operation of all who from personal experience could give information that would result in bringing about the production of a steel rail that could be relied upon to meet the present requirements. I have had considerable experience in the practical manufacture of steel of almost every grade, during the past 40 years, and I shall suggest changes that will bring about the results desired. Doctor Dudley has had a long experience as chemical and metallurgical expert for the Pennsylvania railroad, but he frankly admits that up to the present time both he and other metallurgical experts lack the practical knowledge of steel-making that is necessary to state correctly the reasons for the unreliability of the steel rails now produced. The necessity is self-evident for more positive practical knowledge on the part of these experts of what is possible and what is impossible regarding the practical manufacturing of steel rails from the ingot to the, finished product. Chemical knowledge in steel-making is far in advance of what it was years ago, and might be said to cover every requirement (in that department) for producing reliable steel. The study of the metallography of steel has been of great value, also the physical testing of steel, but this knowledge will only de-

May 1, 1909

By A T. Spathis, K E. Leslie, K R. Blay

Many open pit mining operations seek to control blasting-related movement of ore and waste to minimise loss and dilution. Tracking the movement of ore boundaries can result in the maximisation of ore recovery and minimisation of waste sent to the mill, thereby optimising the economic performance of the operation.A novel solution for tracking the ore–waste boundary location before and after a blast uses subsurface markers placed along the boundary with all measurements and scans conducted remotely from the blast block. Upon system activation, user-operated equipment on the surface determines the three-dimensional (3D) location of the subsurface markers.The patented system concept combines two electromagnetic mechanisms, magnetic positioning and radio frequency through-rock communications to enable remote battery-powered markers, buried within the rock to be accurately located in 3D space.Field trials at a quarry have demonstrated the system can comfortably handle over 100 subsurface markers with a complete scan, including set-up, taking less than an hour. Location accuracy for each marker in 3D space is better than 0.5 m at a range up to 50 m from the magnetic source, and the system has an overall operational range in excess of 75 m.CITATION:Blay, K R, Spathis, A T and Leslie, K E, 2015. A remote, rapid and accurate three-dimensional ore waste boundary tracking system, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 297–306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By A. Boeing

Rock-breaker automation and remote operation improves the safety and efficiency of mining operations. This article presents an overview of the Rocklogic rock-breaker automation system architecture that provides collision avoidance, automated parking, and remote operation functionality. The system consists of a distributed computer control system that interfaces with sensors attached to the rock-breaker, the rock-breaker hydraulics, and the site infrastructure. We present results of an automated Transmin rockbreaker installed in a production environment at an underground Australian mine site. The system has been in production use for over 900 days during which there have been no reported collisions, and 100% adoption of the remote operation technology. As a result, Rocklogic has significantly improved the safety of rock-breaking operations and reduced the rock-breaking cycle time, thereby improving the sites overall throughput.

Aug 1, 2013

By E. Swartzman

"DURING 1951, experimental cleaning studies on both fines and larger sizes of certain Canadian coals were conducted on a relatively large scale in two pilot plants in the United States, large enough to be considered as small commercial units, and in one commercial plant in Canada.One of the pilot plants was a wet washer of a type which apparently has never been .used in Canada, nor has any Canadian coal been tested in it before. In the other pilot plant and in the commercial plant, dry cleaning equipment was used. The commercial plant is the first of its kind to be employed in Canada, and this type is used only to a limited extent in the United States.Fine-Coal Cleaning ExperimentsTest PlantsHydrotator and Hydrotator-Classifier combination pilot-plant with a capacity of about twenty tons per hour. This is a classifier type washer adapted for cleaning fine coal as well as certain intermediate sizes. The Hydrotator deals with that portion of a coal retained on approximately a 24-mesh Tyler sieve, whereas the Hydrotator-Classifier deals with the minus 24-mesh fines."

Jan 1, 1952

By William Crowe Kellogg

By now the term AFMAG has been fairly well introduced to the mining industry. Several papers have been presented and published concerning AFMAG (references 1 and 2). However, the term AFMAG remains rather new to the industry, and the exact place which AFMAG occupies in the minerals exploration field is still somewhat uncertain in the minds of many who may have use for this new and interesting method of electromagnetic exploration for conductive minerals. It is the purpose of this paper to again review the basic theory of the AFMAG system, to describe and - illustrate the equipment and data presentation as used in aerial surveying, and to provide some idea of the cost and nature of airborne AFMAG surveys. This paper is primarily of a general descriptive nature and presents AFMAG theory in a schematic rather than mathematical form; emphasis is placed on the equipment, the present method of data presentation and survey operations, since it is believed that such, information will now generally best serve to inform the mining industry of the characteristics of the AFMAG system.

Jan 1, 1960

By M. H. Pelley

To increase drill fleet capacity and meet increased ore demands at its Carol Lake Project, the Iron Ore Company of Canada initiated a program in 1975 to convert the Gardner-Denver 120 and Bucyrus-Erie 60-R rotary drill fleet from 12 1/4-inch-diameter multi-pass drilling to 15-inch-diameter single-pass drilling. This paper will examine briefly the conversion program , including some tests and results, and examine how the utilization of the 15-inch-diameter blast-holes, coordinated by a comprehensive drilling and blasting program, has improved the drilling, blasting and drilling-plus-blasting aspects of the mine operations, from both economic and operational viewpoints.

Jan 1, 1978

By Cloyd D. McDowell

The Federal coal Mine Health and Safety Act of 1969 has been criticized by those who say it goes too far in controlling the activity of private enterprise and by those who say it does not go far enough in eliminating fatalities and accidents in an accident prone industry. Possibly a better evaluation of this legislation lies somewhere in between. From the viewpoint of the coal industry it can be said that through the efforts of those engaged in mining, both the operator and the miner, the year 1969 marked a record year in mine safety with only 190 fatalities and a frequency of 0.84 per million man hours exposure. This outstanding achievement compared to any previous was the result of a determined effort on the part of a concerned industry to improve its reputation as being the most hazardous industry in the nation. After the effective date of the Act, March 31, 1970, the Bureau of Mines assumed complete control of all safety and health activities of the mining industry. Unfortunately, there was no improvement in the safety record of underground mines in 1970 with the total of 255 fatal injuries and a frequency of 1.04 for the year. The number of fatalities declined to 177 in 1971 but the number of underground coal mines had declined from 5,955 to 2,268 during the two year period. Meanwhile, surface mined coal increased from about 38% of total production in 1969 to over 50% in 1971, keeping the annual production of coal at a normal level but involving fewer men.

Jan 1, 1973

By Ricardo Rocha de Oliveira

A indústria Siderúrgica, nos dias atuais, vem enfrentando grandes desafios, no que tange à sua produção de metais. Com um cenário cada vez mais desafiador, (variação cambial, mercado externo, mão de obra local, custos de produção e logísticos, matéria-prima), as empresas do setor de Metalurgia precisam adotar soluções cada vez mais sustentáveis e com um excelente retorno a curto e médio prazo. Mesmo sob estas condições, o mercado brasileiro não para de inovar em seus processos, principalmente a indústria automobilística, onde há vários desenvolvimentos de veículos automotores que demandam o que há de mais tecnológico e moderno, tais como ligas especiais, adoção de alumínio em sua composição, aços com maior resistência mecânica, entre outros. O Segmento de Metalurgia/Siderurgia é orientado, desta forma, a realizar as mais diversas pesquisas para a otimização de processos e de produção, através de parcerias com seus fornecedores e pesquisa de matéria-prima. Com tudo isso, se verifica que é possível aplicar novas soluções, incorporando-as aos seus processos, obtendo excelentes retornos quanto a ganhos de produtividade e redução de custos de aquisição/manutenção, sem deixar de lado o fator Sustentabilidade e a prática do “Ecologicamente Correto”. Desta forma, as empresas do setor de Metalurgia/Siderurgia conseguem se destacar em seu nicho tecnológico, atendendo a demanda do mercado, apresentando excelente retorno a seus acionistas e garantindo a satisfação de seus colaboradores em todos os níveis dentro da corporação.

Oct 30, 2017

By W. A. Bain

"AbstractProduction from the Excelsior Reservoir has amounted to approximately one million barrels. This production has caused a 'Pressure •drop of 10 p.s.i. from the original pressure of 1,245 p.s.i.g. Volumetric balance calculations indicate that the pool as being produced by a water drive whose strength is •probably unsurpassed in Western Canada. It has also been shown by 'unsteady state' calculations that the reservoir will still be above the saturation pressure of 915 p.s.i.g. at the time of depletion. The average permeability of the producing formation is approximately 1,000 millidarcys and, consequently, well draw-downs are very low. The field is essentially a bottom-water drive and calculations have shown that gravity drainage will greatly assist the recovery of oil. Water flooding data on several cores •have placed the flushing efficiency at •approximately 50 per cent, which indicates a recoverable oil-in-place of 17.7 million stock tank barrels. Calculations and field data indicate that the MER for the early life of this field is probably as high as 8,000 to 10,000 stock tank barrels per day.IntroductionTHE EXCELSIOR NISKU oil reservoir is located about twenty miles northeast of Edmonton. The field was discovered in November, 1949, by Imperial Excelsior N.o.1 well, in Lsd. 13, Sec. 3, Twp. 56, R. 22, W. 4, at a depth of 3,850 feet.Since discovery, development has continued on a 40~acre spacing pattern. At the end of 1951, drilling over approximately 80 per cent of the estimated productive area of 1,680 acres had established 32 we1ls capable •of production. The field •has been fairly well delineated by dry holes on all but the eastern flank ."

Jan 1, 1952

By F. D. Aaring

"IntroductionTHE PINCHER CREEK gas condensate field, in Township 3, Range 28, and Townships 3 and 4, Range 29, West of the Fourth Meridian, was discovered in 1947 by the Canadian Gulf Oil Company with the completion of Pincher Creek No. 1 well in the Madison lime-stone of Mississippian age.This discovery was the result of a great deal of detailed seismic work in the area and is a credit to the geophysical personnel of the Company. The depth of the reservoir varies from 7,400 feet to 8,200 feet subsea, with the established water level at -8,200 feet. The predicted depth was but a scant 100 feet from that found in the discovery well, at 11, 705 feet. Since the discovery of the reservoir, three additional wells have penetrated the Madison limestone and have further verified the original •seismic interpretation of the limits of this reservoir.To date, •only a very small amount of gas has been produced from this field. Consequently, the reservoir studies that have been made so far are predominantly based on investigations of the phase behaviour of the fluid and physical characteristics of the reservoir rock. In view of the above limitations, it has been necessary to set up and perform model reservoir studies with the fluids and to recover as much core from the productive Madison limestone as possible in order that it might be analysed by conventional laboratory technique and be subjected to detailed microscopic geological examination."

Jan 1, 1952

By George Gazetas, Sissy Nikolaou, Fani Gelagoti, Irene Georgiou, Rallis Kourkoulis

"The need to shift geotechnical design from a “factor of safety” to a “performance based” design (PBD) approach has increased rapidly in the past years following examples from structural engineering. PBD supports sustainable engineered systems that target project-specific geotechnical behavior objectives and results in more rational and, in most cases, less conservative solutions. Resiliency, efficiency, risk optimization, and cost-effectiveness are key components of this approach. For design of retaining walls, the concept of mechanically stabilized earth (MSE) systems combines these attributes, while being environmentally friendly and adaptive to variable construction conditions. Natural hazards, such as earthquakes, may drive the design of MSE systems whose reliability depends on their performance under extreme events. In this paper, the authors compare the seismic response of an MSE steel-reinforced vs. concrete-reinforced retaining wall. The MSE system is composed of a grid of longitudinal and transverse ribs which internally enhances the capacity of the soil backfill. Results of fully non-linear twodimensional (2-D) numerical finite element analyses using two commercial programs with emphasis on the interface conditions are presented. The pull-out resistance of the grid used in the numerical simulation was evaluated from actual pull-out experiments. The results demonstrate a superior performance of the MSE system as compared to the concrete one, especially when subjected to strong seismic excitations.INTRODUCTIONThe idea of performance-based geotechnical engineering is not new, and has been evolving as our perception for ‘good’ performance has also evolved (Kramer, 2008). In early practice, the only criterion for achieving good performance was to avoid failure; designers had only to ensure that the available capacity of the geotechnical system is sufficiently higher than the expected demand (i.e. Load and Resistance Factor Methodologies). Yet, even when the key design requirements against collapse are satisfied, the system may still be placed into a condition in which the deformation constraints are not met (Bolton, 2012). To address these issues, geotechnical design has been developing into a predominantly performance-based approach that correlates deformation considerations to the severity of the experienced loading. As such, in earthquake-related problems, the definition of good performance of a geotechnical system is no more unique; for a low intensity earthquake the system should remain serviceable (i.e., the developed deformations should remain low), whilst for the design earthquake the maintenance of lifesafety is the single performance criterion."

Jan 1, 2016

By D. Minney

The quality of resin used in South African collieries is currently controlled according to South African Bureau of Standards, "SABS-1534:2002". It has however been found that resin which passed the SABS tests failed in underground short encapsulation pull tests. An investigation was therefore conducted to determine the characteristics of resins that are currently being used in collieries. A series of in situ short encapsulated pull tests was conducted to determine the effect of expired resin on support performance. The results showed that the longer the time after the expiry date the poorer the resin performance. A series of resin-torque tests has been performed using Anglo Coal's testing facility. The following parameters were investigated on different resins: Spinning speed, Mixing time, and Setting time. An attempt was also made to develop a new quality control procedure for resin. This procedure enables mining personnel to make sure that the quality of resin can provide the required support performance. The effect of spinning speed on resin performance was also investigated. The results showed the resin gelling times of resin decreases as the spinning speed increases. It is found that over-spinning with slow speed roofbolters may result in decreased bond strengths. It was found that a 30-second resin (10-second spin, 30-second hold) should never be spun more than 20 seconds, even with very slow roofbolters (100 rpm).

Jan 1, 2005

By L. R. Stoiser

The mineral resource potential of the Los Bronces deposit was successfully evaluated by an intense, coordinated program over a 37-month period (April 1978-May 1981) as part of an economic feasibility study. The program included more than 120 km of core drilling, 63 km of access road construction under adverse topographic and climatic conditions, detailed geological mapping, plus other related activities. This Tertiary-age copper-molybdenum deposit is composed of an earlier mineralized porphyry-type body intruded in part by a large complex of mineralized hydrothermal breccia pipes. Both intrusive and extrusive igneous rocks are present. Erosion, oxidation, leaching, and supergene enrichment of copper have resulted in a deposit now exposed at the surface that contains more than 368 Mt grading about 1% copper equivalent as sulfides.

Jan 1, 1982

By Pramod C. Thakur

Coal is a major source of energy in the world today and will, undoubtedly, continue to be so for the next few centuries. Naturally, a great number of studies has been made of its physical and chemical properties. Unfortunately, the work on technical properties which influence the mining of coal and the consequent yield of inflammable gases and respirable dust particles has not progressed at a comparable pace. Coal is a brittle material. Irrespective of the mechanism of breaking coal, some dust is always produced. In mining parlance dust is defined as solid particle, smaller than 100 microns (micron = 10-6 meter), in size Coal dust, when raised into a cloud, creates two well known hazards in mines, namely, the coal dust explosion and Coal Workers' Pneumoconiosis (CMP). The latter is, perhaps, the greatest environmental hazard in U.S. coal mines today. In this context it is not only natural but also necessary to investigate the proneness of a coal seam to respirable dust production. It has been established that the amount of dust produced is a function of two groups of variables (1), (2), viz. (1) Material dependent variables, e.g., moisture content, compressive strength, hardness, etc. (ii) Breaking mechanism dependent variables, e.g., type of machine, depth of cut, etc.

Jan 1, 1973