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By Marco Quirion

The Daniel-Johnson dam, formerly named Manicouagan-5 (Manic-5), is located 800 km northeast of Montreal (Quebec) in Canada. This is the largest multiple-arch concrete dam in the world consisting in 13 arches and 14 buttresses. Since its construction in 1969, various type of cracks have appeared on both downstream and upstream faces of almost all the arches of this concrete dam. As a part of the Daniel- Johnson’s dam safety assessment program, Hydro-Québec is currently performing structural analysis of the dam with advanced numerical models to better understand and predict the dam behaviour. Because the buttresses transmit all the arch loads to the rock mass, determination of the properties of the dam foundation should not be neglected in dam global safety analysis and also to insure that reliable input parameters are used in the dam numerical simulations. This paper summarizes the past and the more recent investigations of this foundation used to assess its safety and stability. Moreover, the use of rock mass classification to estimate the deformation modulus, based on empirical equations, gives values in the range of 30 to 40 GPa that are higher than expected values. Using those values in the numerical simulations for dam structural analysis gives an excellent correlation with displacements monitoring of the buttresses.

Jan 1, 2015

By D. Roy Eccles

A multi-element geochemical response, with contrasts of up to 29 times background, was obtained in soil above the Mountain Lake Diatreme, northwestern Alberta. The overall geochemical signature is indicative of an ultramafic source; geochemical responses contain elevated concentrations of Co, Cr,O, Cu and Ni with the presence of high Ba, Ga, HI, PO,, Rb, Ta, Ti and light rare earth elements suggestive ofa kimberlite or lamproite body. The shape, or morphology, of the enzyme leach-based geochemical signature over the Mountain Lake Diatreme combines moderately strong to strong oxidation halos, or a rabbit's- ear geochemical profile, with a sharply-defined apical geochemical profile. Because some Alberta diatremes discovered to date form positive topographic highs, the resultant geochemical signature may express the soil development profile that forms directly on top of kimberlitic and lamproitic bodies. The enzyme leach technique, which has proven to be a useful tool in base metal, precious metal and petroleum exploration, may have a significant impact on exploration for kimberlite, lamproite and related rocks in Alberta by providing industry with a useful and cost effective tool to probe blind and/or buried anomalies identified by airborne and ground magnetic surveys in areas of glacial overburden.

Jan 1, 2001

By J. G. Trowell, D. T. Magee

"IntroductionMANITOBA'S first recoverable oil was from the California Standard Daly 15-18 well in Lsd. 15, Sec. 18, Twp. 10, Range 27, W.P.M., completed early in 1951. This well also gave the first indications of commercial production in the Williston basin, which is centred in North Dakota and extends into southeastern Saskatchewan and southwestern Manitoba. Subsequent drilling in the Manitoba portion of the basin has revealed the presence of oil in more or less commercial quantities at various points in an area approximately four townships in width and eleven townships in length.Although completions are becoming fairlly widespread in the area,, the greatest activity is in the Virden district, with the focal point in the Daly field, approximately eight miles west •of Virden. This paper will deal with the various techniques used in the Daly field, where •completion problems have •been unusually troublesome. Techniques evolved there have already been used with success at other points in southwestern Manitoba.Daly FieldGeneralTo date, all production has been from the Mississippian limestone, which is encountered •at depths ranging from 2,300 to 2,500 feet. Pay thickness is •of the order of 100 feet. Core analyses indicate average porosity .of about 9 per cent but permeabilities, for the most part, are extremely low."

Jan 1, 1953

By Lynn I. Kelley

Potash is the primary industrial mineral produced in Saskatchewan, followed, in terms of gross value, by aggregate, sodium sulphate, salt, potassium sulphate, peat, clays, silica sand, calcium chloride brine and "clinker." Potentially economic deposits of kaolin, diamond and building stone are under evaluation.

Jan 1, 2001

By C. Zangerl, H. Lechner

"Large scale rock slides in deeply incised Alpine valleys are common hazards that can endanger human life, settlement areas and critical infrastructure such as highways, railways and reservoirs (Bonzanigo et al., 2007). In order to perform reliable forecasts of the behaviour of rock slides influenced by large dam reservoirs the geometry, the kinematics, the deformation behaviour and the hydrogeological situation need to be understood profoundly. Based on generic rock slide models the influence of the rock slide geometry on the stability as well as the impact of the buoyancy forces and water load of the reservoir at the toe of the slope are the main focus of this study. Various assumptions of hydraulic conductivity, groundwater conditions of the rock slide and impoundment depth of the reservoir are analysed using limit equilibrium approaches.Generally, deep seated rock slides are characterised by deformation along one or multiple shear zones where most of the measured total slope displacement localizes. Many large rock slides, especially those observed in foliated, mica-rich crystalline rock masses (e.g. paragneisses, mica schists, phyllites), do not fail suddenly or reach high velocities. Instead, many of them move slowly and reach velocities of centimetres per year or even less. Some show episodic accelerations, sometimes reaching alarming levels, but then subside to non-critical levels again. However, there is a potential that deep-seated rock slides fail rapidly, develop into far-reaching run-out rock flows, and cause catastrophic events. Whereas the role of triggers in promoting phases of acceleration is often understood, the same cannot be said regarding the kinematics and dynamic processes by which the rock slide mass decelerates, re-stabilises or accelerates to a catastrophic degree once the trigger impetus has been removed. Thus key questions of the presented work concern the geotechnical, geometrical and hydrogeological conditions under which a slowly moving rock slide is triggered to accelerate to irreversible, maybe dangerous velocities. The development of the sliding zone is generally influenced by pre-existing discontinuities such as brittle fault zones, shear and tensile fractures, foliation and bedding planes. These geological structures determine the geometry of the sliding zone which can either be rotational or translational. During the gravitationally induced failure process the geometry of the rock slide undergoes a change.Several observed post-failure geometries in metamorphic rocks show a concave topography in the middle to upper part of the rock slide and a typical convex or bulge-like topography at the toe of the slope (Zangerl et al., 2012). Whereas the sliding zone of the upper part of such a rock slide mass is rather steep and planar, the inclination of the sliding zone at the toe can be close to zero and act against the driving forces (Alonso et al., 2010). A shear zone that meets alluvial deposits at the foot of the slope encounters a stabilizing impact on the mechanical behaviour. This buttressing effect of alluvial sediments has a remarkable influence on the slope stability."

Jan 1, 2015

By Blaycock. S. C.

WE should indeed feel proud and satisfied with the accomplishments of our great mining and metallurgical. industries during the past quarter of a century, for they have vastly exceeded those of any previous period of like duration. 1 feel that Canadians, and particularly those in the mining industry, should know more concerning the important role our industry will be called upon to play in the present war. Our Empire metals will be an outstanding factor in this conflict. Every man connected with the industry, from the lowest paid labourer to the highest official, can feel proud that his every effort results in more and more production of those metals which will help to give the Empire supremacy. He can feel assured that, by sticking to his job and by putting his whole heart into his work, he is making a contribution towards winning the terrible struggle in which our Empire and our gallant French allies are engaged. These two great peoples will have ro bear the brunt of the task of ridding the world of the menace of those who would set up force. and might in the place of right and justice in the settlement of international affairs. As the present European crisis developed, it became evident that they, alone, would have to accept the challenge and fight the enemies of Democracy to ensure the survival of the small nations of Europe and, indeed, of the great democratic powers themselves. The acquisitive eye of the German leaders had looked far ahead and they had realized that the eastern European states, already reeming with population, were no solution to Germany's space problem; but they thought that these states could be gobbled up one by one, each in turn strengthening Germany's might until it could successfully challenge France and England. No glimmer of doubt dimmed their vision. The two great democracies once subdued, they could proceed to seize Canada and the United States. This clone, they would have an abundance of room to expand, as well as those resources-grain, timber, cotton, nickel, iron, lead, zinc, copper, gold, silver, sulphur, oil-which German statesmen have always coveted. Von Ribbentrop, von Alvensleben, Bernstorff, and many others have made exhaustive studies of our resources. German rulers had been told that the French would not fight and that the British could not. They knew of the rust on the British war machine. There was no cloud in the sky; their fond dream was at last robe fulfilled.

Jan 1, 1940

By Xiu-Xiang Tao

This study investigated bio-liquefaction of lignite and its model compounds of thymol, bezioc acid and quinoline by a fungus, Hypocrea lixii AH. It analyzed, during bio-liquefaction, enzyme activity of oxidase, LiP, Lac, MnP and polyphenol oxidase, and degradation products by UV-Vis, FTIR, 13C NMR and GC-MS. The results showed that the bio-liquefaction percentage (by mass) of lignite was up to 44.86 %. The bio-liquefaction products of lignite were mainly aniline, amide, ether, carboxylic acid ketone and ester. The aromatic ring number was 1-3 with an aromatic carbon ratio of 0.328, which indicated rings opening, bonds breaking and oxidation reaction. By considering with the enzyme activity analysis results, it showed that LiP and Lac catalyzed reactions to open aromatic cycles and to break bonds; esterase to break ester bond; and peroxidase in oxidation reaction.

Aug 1, 2013

By Shuo Zhang, Wenying Liu

"In dump leaching, the efficiency of metal extraction from ores is strongly influenced by the mechanisms of fluid flow. Particle size distribution acts as a fundamental parameter in the determination of fluid flow properties in packed ore beds. In this study, we investigated the particle size distribution in dump leaching by using image analysis technique. The results showed that the particles in the dump varied from smaller than 2 cm to larger than 200 cm in diameter. P80 was calculated to be 200 cm, which was significantly higher than the historical data used by the operation. P25, P50 and P80 were found to increase non-linearly with increasing depth towards the toe of the dump, suggesting the segregation of fine and coarse particles. The image analysis results were verified by applying the rock fragmentation models. The model with the Swebrec function was found to be in better agreement with the image analysis results. Future research will investigate the effect of particle size distribution on the behaviour of fluid flow.INTRODUCTION Fluid flow plays an essential role in the extraction of valuable metals using heap/dump leaching (Amos et al., 2009). The rates of the chemical leaching reactions and microbial activities determine metal concentrations in the leachates and therefore the efficiency of the metal extraction. The reaction rates are influenced by two fundamental processes: transport phenomenon and reaction kinetics (Bouffard & Dixon, 2001). The transport phenomenon refers to the percolation of fluids through channels and pores in a packed ore bed, which carries lixiviants and reaction products to/from ore surfaces by convection and diffusion. The percolation rate of the leaching solution is determined by the hydraulic conductivity of the packed ore bed, which is a function of the permeability and the degree of saturation (Guzman et al., 2008). Permeability, an intrinsic property of a packed ore bed, is strongly influenced by the particle size distribution of the ore grains (Bouffard & Dixon, 2001). Hence, the objective of this study was to investigate the particle size distribution in dump leaching."

Jan 1, 2017

By Xiang-dong and Zhu, Xia-jie Hao, Yi-lin Fan, Quan Jiang, Lian-xing Hu, Xia-Ting Feng, Shao-jun Li

"Columnar jointed basalt (CJB), which typically originates from lava flows, is characterized by a special geological structure. The joint network inside the CJB is self-organized into a rough hexagonal arrangement. The field test and measurement during the unloading excavation showed that the columnar joint sets and other internal joint sets not only are important for determining the mechanical properties of the CJB, but also induced its asymmetric unloading deformation and failure. A constitutive model, which considered mechanical deterioration of both the joint sets and rock blocks, was also developed to simulate the unloading behaviour of the CJB. The crack-confinement supporting method for surrounding CJB was developed to overcome the failure of columnar jointed rock mass in the diversion tunnel. Application to the CJB segments of the diversion tunnels in the Baihetan project indicated that this supporting method was reasonable and efficient. INTRODUCTIONColumnar jointed basalt (CJB) rock mass, which typically originates from lava flow, is characterized by a special joint structure. The joint network of the CJB is self-organized into a roughly hexagonal arrangement and leaves behind an ordered colonnade. The widely accepted current view regarding the formation of columnar jointing involves a thermally induced contraction–cooling mechanism (Peck and Minakami, 1968; Degraff and Aydin, 1987; Budkewitsch and Robin, 1994; Lore et al., 2000; Goehring et al., 2006). Although the columnar basalt formation mechanism is fairly understood, the geotechnical characteristics of such rock mass are not well established. In practice, joint sets always induce the multi- failure modes of surrounding rock in the tunneling space (Ibarra et al., 1996; Waltham and Swift, 2004; Mahendra and Bhawani, 2008).According to conventional wisdom in rock mechanics, structural joints affect the mechanical response of rock mass by introducing strong anisotropic effects (Barton and Bandis, 1980; Hudson and Priest, 1983; Brady and Brown, 1985). The columnar jointed rock mass should be considered an anisotropic material given that the joint sets are distributed with some principal directions and characteristic spacing distributions (Cundall and Fairhurst, 1987; Hoek et al., 1998; Wu and Wang, 2001; Budetta and Nappi, 2011; Fortsakis et al.,2012). Columnar jointed rock mass would result in structurally controlled failure patterns, even serious disasters during underground excavation because of the low shear and tensile strengths of intensely joints (Gencer,1985 ;Ishida and Uchita, 2000; Jia and Tang, 2008). The CJB rock mass in the Baihetan hydropower station has exhibited serious stability issues, including sliding, fracturing and even collapse (Shi et al.,2008). Therefore, the geotechnical and geomechanical characteristics of such rock mass should be assessed through in situ investigation and numerical analysis to minimize future accidents during underground unloading excavation."

Jan 1, 2015

By M. Abumiya, N. Onodera

Stabilization of arsenic via the precipitation of large-sized scorodite (FeAsO4·2H2O) particles usually involves the use of expensive autoclave systems operated under high temperature and pressure conditions. Alternatively, DOWA developed a novel scorodite synthesis process (DMSP®) wherein the Fe(II) ions in solution containing As(V) ions were oxidized by O2 gas under atmospheric pressure. In this process, crystalline scorodite particles were formed via the formation of a gel-like precursor containing Fe(II). Based on this concept, in this study, we have demonstrated the synthesis of scorodite particles by the addition of Fe(III)-containing solution to the experimental solution containing Fe(II) and As(V) ions, without the O2 gas oxidation process. Ferric sulfate (Fe2(SO4)3) was used as the source of Fe(III) ions. Results indicate the precipitation of scorodite particles, comparable to that of the O2 gas oxidation method.

Jan 1, 2014

By Marc Boyer

Modern civilization, modern industry, and modern standards of living, bring into, sharp relief the present-day essentiality of metals .and minerals, and the wide and diversified use which is made of them. Any attempt, therefore, to appraise the international situation today must take into consideration the metal and mineral resources of the world. If, as some believe, the world is divided into two distinct ideologies of political belief, one unalterably opposed to the other, so that armed conflict is unavoidable, then the question of national strength in mineral resources becomes of paramount importance. If, however, it is possible to avoid war by raising the standard of living in the underdeveloped ?areas of the world, thus ensuring all peoples everywhere against the dread spectres of starvation and disease, then the development of the world's mineral resources assumes even greater importance. Today it is difficult to realize that, prior to the industrial revolution in Great Britain, only a few of the metals and minerals now in common use entered into the everyday life of the people. !iron and steel, copper, lead, tin, and zinc, usually in .their unalloyed forms, along with the more common industrial minerals, were those most widely used, and then only in limited amount. With the advance of technology in metallurgy and in fabricating skills, the list of commercial metals and minerals has expanded until today they number more than eighty.

Jan 1, 1951

By A. Kowalski

Telvis Limited, manufacturer of an emergency communication dispatcher's broadcasting system, now introduces the possibility of a remote software upgrade to its devices. The paper presents methods, features and ways to accomplish this task. It describes the mechanisms used and the opportunities that arise from the use of this type of functionality. The mechanism software update presented applies to devices on the surface and in underground areas of mines. The electronics used currently allow the use of remote software updates, but the mining equipment makes little use of these methods. This paper aims to start the discussion on this topic and tries to lay the path of development by showing one of the first examples of the application.

Aug 1, 2013

By Ltd Changsha Research Institute of Mining and Metallurgy Co., Shi Yunliang, Luo Yunbo, Chen Jun, Liu Miaohua, Xiao Jinxiong, Long Yan

"A refractory lead-zinc oxide ore located in Yunnan has hundreds of tons of metal reserves, which is hard to be recovered effectively by conventional oxide ore beneficiation methods. In this study, by sulfidation roasting of raw-ore, sulfide deposit is formed on the surface of the lead-zinc oxide ore, and then the roasted ore is processed with bulk flotation. The test results indicate that a bulk concentrate with grade of 7.85% lead and 34.24% zinc, recovery of 79.13% lead and 79.04% zinc, respectively, can be obtained by using conventional sulfide ore flotation method.The sulfidation process shows that pyrite in the raw ore releases S firstly, then S reacts with PbO and ZnO to transform into PbS and ZnS. When the mole ratio of sulphur:zinc is 0.59, the surface of smithsonite is covered with a layer of zinc sulfide. When the mole ratio of sulfu:zinc rate is 1.47, entire simthsonite particle is transformed into zinc sulphide. Thus the transformed particles can be recovered by flotation without complete sulfidation.INTRODUCTIONWith the increasing demand for zinc and decreasing of zinc resources, people pay more attention on development and utilization of zinc oxide ore. However, zinc oxide ore has wide range mineral kinds, complex mineral composition, disseminated fine-grained particle size, and high content soluble salt, so current study results about the zinc oxide ore with conventional flotation are not satisfactory. So far, process dealing with zinc oxide ore includes: sulfuration (Na2S)-flotation, direct flotation with fatty acids collectors, metallurgical methods, in which sulfuration flotation is the most widely used method. The basic principle of sulfuration flotation method is firstly roasting oxide ore with vulcanizing agent, and then recovering the sulfurated oxide ore with flotation, which is similar with recovering nature sulfide ore by using conventional collectors such as amines and xanthate."

Jan 1, 2016

By S. G. Coultis

Turner Valley is in the foothills of the Rocky mountains, at an altitude of 4,000 feet, and is 42 miles south west of Calgary. The present producing area is 8 miles long by 1 1/2 miles wide, while drilling is being carried on over an area of 10 miles by 2 miles . There are 32 wells producing, 26 wells drilling, and 17 wells shut down, making a total of 75 wells, which range in depth from 2,160 feet to 5,900 feet, varying according toa the well location on the anticline centre wells being shallower than those located on the flank. The first indication of possible production in this field was a gas seepage on the banks of Sheep river, in what is now the Royalite plant yard (Figure 1). Geologically, this seepage proved to be located on an anticline running through the valley in a southwesterly direction. The Calgary Petroleum Products Company was formed in 1912, and under the direction of Mr. A. W. Dingman, President, and associates, the first well was drilled. Production was obtained in this well. Gas was found in several horizons from 884 feet to 3,960 feet, and oil at 1,557, 2,718 and 3,839 feet. In May, 1914, oil was struck at a depth of 3,839 feet, this being a light straw-coloured oil of 60 gravity, which was blown spraying from the well accompanied by three to four million feet of gas. The latter contained some 200 grains of hydrogen sulphide per 100 cu. ft., giving it the disagreeable odour so well known in Turner Valley gas. This strike caused considerable excitement and started the famous 1914 boom, when some 400 oil companies were formed. The well referred to produced from two to five barrels of 60 gravity oil per day, and 4,000,000 cu. ft. of gas. The oil was used in the crude form in cars and trucks.

Jan 1, 1929

By J E. Curfman

This paper deals with using track-type and rubber-tired machines in the ripping and handling of overburden and ores. The techniques and proper attachments pertaining to the ripping of materials are covered in some detail. Production and relative costs of ripping, as against other methods, are covered in cases pertaining to the mining industry. The use of the refraction seismograph in predetermining the rippability of materials, including a chart relat-ing velocity to rippability, is covered. This operates on the principle that sound waves travel through subsurface materials at different velocities, depending upon the degree of consolidation of the material. It is known that the same factors that affect consolidation also affect rippability. Proper equipping of the tractor to insure maximum efficiency is also covered in some detail. Introduction T HE idea of loosening consolidated materials prior to further handling and processing is probably as old as man. The purpose of ripping is to provide fragmentation of rock and loosening of consolidated materials.

Jan 1, 1965

By A. G. Beer

The evolution of microstructure is examined during the annealing of hot worked magnesium alloy AZ31. The influences of deformation and annealing conditions on the developed microstructures are assessed. It is found that annealing at a low temperature (300 °C), after deformation at a low temperature and strain rate (300 °C and 0.001 5-1 respectively), results in the development of abnormally large grains. With increasing values of Z (lower temperatures, higher strain rates), static recrystallization of the dynamically recrystallised structure takes place; smaller annealed grain sizes are attained and the time at which coarsening begins is reduced. Whilst both the deformation and annealing conditions influence the time it takes to reach a stable annealed microstructure, the grain size attained is governed solely by the prior deformation conditions employed.

Jan 1, 2006

By A. Brown

IN INTRODUCING the subject of rock pressures, it may safely be assumed that mining men are only too familiar with the physical effects of strata stresses that accompany the extraction of minerals. It may be further assumed that they have, as individuals, arrived at certain conclusions regarding their nature, based upon years spent in observing such phenomena and in learning how to continue mining in spite of them. Such hardly won experience forms the core of what is often referred to as 'pit sense'. This essential type of knowledge is not ?based on theoretical considerations, nor can it be found in text books. It is highly individualistic in nature and almost impossible to pass on from one generation to another in terms of precise rules for guidance. It is this aspect of individual judgment based on practical experience that has led to the significant phrase The Art of Mining.

Jan 1, 1956

By M. Mirnezami, J. A. Finch, S. Uddin

A fast, reliable and practical way of measuring zeta potential using sedimentation potential method is proposed. A cell was designed along with the instrument control software to determine the required variables simultaneously i.e. sedimentation potential, specific conductivity, volume fraction of solid as well as pH. High purity alumina and silica powders were used as test samples. Measured zeta potential using the proposed technique was comparable with the results by electrophoresis.

Jan 1, 2009

By DONALD E. BARNETT

Since the days of early settlement ew Brunswick has produced a variety of industrial minerals but it is perhaps only the recent discoveries of significant reserves of potash that have elevated the meaning of industrial minerals in their contribution to the provincial economy. With potash production commencing in July 1983, the role of industrial minerals will increase significantly to the value of mineral production in the province.

Jan 1, 1984

By Elbasher M. E. Ahmed, Indresan Govender

"A mechanistic model of axial charge segregation in rotating drums is presented. We show that granular material composed of different frictional properties diffuse into axial bands as a consequence of concentration fluctuations in the free surface layer that is caused by friction-limited mobility. A Bagnoldian stress assumption ensures an asymmetric free surface profile thereby providing the essential ingredients for the evolution of axial bands and the subsequent band coarsening observed in the literature. The formulation is sensitive to the boundary conditions of tumbling mills, including particle size and density, mill speed, inter-particle bulk friction, end wall friction and drum geometry (length and diameter).INTRODUCTIONA mechanism to fully describe the axial segregation of charge in a rotating drum remains elusive to the mineral processing industry. With regard to low aspect ratio mills (like ball mills), current thinking favours the use of closed circuit mills with correspondingly low residence times to offset the completely random contact probabilities between particles and balls (Wills & Napier-Munn, 2006). Conical end caps are argued to exploit the centrifugal force to achieve a regular gradation of ball size along the mill with larger sizes at the feed end and smaller ones closer to the discharge. However; segregation along the length has been observed in the absence of conical end caps (Oyama, 1939; Levine, 1999): In these investigations, sufficient differences in the particle’s mechanical properties (particle size, density, shape, surface roughness) was enough to successfully achieve axial segregation. Figure 1 shows the segregation of a bimodal distribution (by size) into bands of larger (darker colour) and smaller (lighter colour) particles."

Jan 1, 2016