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By D. A. Livingstone

Abstract Golden Manitou Mines, Limited, nine miles east of the town of Val d'Or in northwestern Quebec, are presently milling, at the rate of 1,000 tons daily, a relatively complex 3.11-phide ore and producing, in decreasing order of value, zinc, silver, gold, lead, and copper. The products are a zinc concentrate, a silver-lead-copper concentrate, and a silver-gold precipitate from cyanidation. Although several independent pre-production metallurgical investigations into the treatment of the ore were carried out, current practice is different from any of the recommended methods and, while still leaving room for improvement, is considerably more effective than earlier performance. Flow-sheet developments from the commencement of operations in 1942 are dealt with briefly, showing the reasons for making numerous changes, the shortcomings of the various schemes tried, and, finally, covering data pertinent to present-day practice. From the recovery standpoint, silver has presented the greatest difficulty. The writer's association with the Company coincided with the start of production. Characteristics of the Ore The predominant metallic minerals present in the ore, in decreasing order of their abundance, are: pyrite, sphalerite, galena and chalcopyrite, with lesser amounts of argentiferous tennantite-tetrahedrite, arsenopyrite, covellite, bornite, and chalcocite. The sphalerite is mostly light in colour, sometimes colourless, and practically free from combined iron. Some of the sphalerite is very closely associated with minor amounts of pyrite, chalcopyrite, and galena. Pyrie is abundantly disseminated as medium to fine grains; more rarely it is massive and contains occasional grains of sphalerite, galena, and chalcopyrite.

Jan 1, 1952

By R. S. Adhikari

The changes in defects patterns or in element condition index during visual inspection of bridges are primary concerns for inspectors. This paper presents a new approach for change detection of defects in bridges by identifying changes in texture patterns through spectral analysis of digital images. The commonly used method for change detection is image differentiation. This subtraction method requires images to be of same size, scale, and rotation. However, no two images are same in real practices. Thus, image registration is required to align images and to produce change maps. This process is tedious and it is difficult often to achieve a good registered image. But, the change detection task can be readily modeled in frequency domain for texture patterns discrimination and also for quantifying their properties. This paper proposes a novel approach for change detection by transforming digital images into Fourier spectrum. In new coordinate system, 1-D signature functions can be drawn which facilitates easy comparison of textures in different directions. The proposed methodology provides useful tools for comparison of inspection history graphically and quantitatively. In practice, expensive sensors are used to detect subtle change in defect patterns. The proposed method can be used to detect any subtle change in defect patterns using digital images at much lower cost.

Aug 1, 2013

By J. S. Redpath

Eighty feet of overburden, thirty feet consisting of fine, water-bearing sands, was encountered during the construction of a shaft collar for Chimo Gold Mines Limited at its Louvicourt, Quebec, property. This paper describes the excavation and construction methods used on the project. Open-cut methods, a sheet pile cofferdam, chemical grouting and special blasting methods were used during excavation. Concrete placement was hampered in the lower portion by a heavy water flow, and aided in the upper portion by an unusual method of form bracing. Plant and • pum11ing facilities are also described.

Jan 1, 1966

By John Taylor

"The Highvale Mine in Alberta is owned by TransAlta Utilities Corpora/ion and operated by Mana/fa Coal Lid. It is the largest coal mine in Canada and in 1982 supplied 8.6 million 1onnes of sub-bituminous ""B"" coal to TransAlta's Sundance Ceneraling Plan/. Annual produclion is scheduled to increase in 1983 when the firs/ unit of the new Keephil/s Generating Plant comes on stream and is expec/ed to exceed 11 million tonnes by 1985 when the second unit is commissioned. Coal is mined from several pits in a multi-seam operation. Comprehensive maintenance, drainage and environmental programs form a major part of the operation.IntroductionThe Highvale Mine is located eighty kilometres west of Edmonton, Alberta on the south shore of Lake Wabamun (Fig. I). The mine is owned by TransAlta Utilities Corporation (T.A.U.) and is operated by Manalta Coal Ltd. In 1982, 8.6 million tonnes of coal were supplied to T.A.U.'s 2100 MW Sundance Generating Plant, making it the largest producing coal mine in Canada. By 1985, with two 375 MW units on line at T.A. U .'s new Keephills Generating Plant, annual production is estimated to exceed eleven million tonnes. The generating plants accept crushed unwashed coal from the mine via the coal handling plant system conveyor belts. The coal is classified as sub-bituminous ""B"" and has an average heating capacity of 18.6 MJ I kg.HistoryPrior to 1943 only small scale mining took place in the Highvale area. Between 1943 and 1961 two strip mining companies, Mount Royal Collieries and Continental Collieries operated on the present mine site. Both operations excavated coal along the south shore of Lake Wabamun."

Jan 1, 1985

By J. Finch, Wei Zhang

In this paper we describe the synthesis of a new homologous series of linear Polyglycol-based frothers that consist of Ethylene Oxide (EO) and hydroxyl as hydrophilic groups and Propylene Oxide (PO) and alkyl chains as hydrophobic groups. The synthesized frothers were of two types: Alkyl-Ethoxy-Propoxylate (abbrev. CnEOlPOm) and Alkyl-Propoxy-Ethoxylate (CnPOmEOl) giving: (a) different number of groups and chain length, and (b) different locations of the groups. The identities were confirmed by proton nuclear magnetic resonance (NMR) spectroscopy and total organic carbon (TOC) analysis. The characterization of the products was carried out in a bubble column. At steady state, bubble size, gas holdup and water overflow rate were measured as a function of frother concentration. The results indicate that increasing number of PO groups led to significant decrease in bubble size, and increase in gas holdup and water overflow rate. Increasing the alkyl chain length, gave similar but less pronounced trends. There was no impact of increasing the number of EO groups on bubble size but there was an in increase in gas holdup and water overflow rate. Changing the location of the PO and EO group had a significant effect on all three parameters.

Jan 1, 2015

By Y. J. Yu, C. D. Zhang, Y. S. Zhao, W. G. Liang, Y. D. Geng, J. L. Bi

"In this study, the coefficient of thermal expansion (CTE) and thermal conductivity (TC) of shale in two perpendicular directions, vertical and parallel to the bedding of the rock, are firstly measured by experiment. The experimental results show that the CTE of the shale in the vertical direction is 1.69 times as much as that in the parallel direction, while the TC in the parallel direction is 1.83 times larger than that of the vertical direction. Based on the no initial strain assumptions, numerical simulations for the thermal cracking in shale are carried out with the obtained coefficients. Using finite element method and thermal-mechanical coupling theory, two fracture mechanical parameters, KI and J-integral of the shale are also analyzed for the shale thermal fracturing. The simulation results show that both KI and J-integral reach the maximum when the fracturing angle equals to 0° in the shale, namely parallel to the bedding direciton. It is also found that the two fracture parameters decrease with the fracturing angle increasing. Additionally, the thermal fracturing effect of the shale is evaluated under a given scenario. The study is significant for shale oil or gas recovery by in situ pyrolyzing method.INTRODUCTIONOil shale is regarded as a kind of unconventional resource that can contribute to production of shale oil and hydrocarbon gases (Rahm & Dianne, 2011). As is known that there is a large deposit of oil shale in China, and present technology for exploiting oil shale still concentrates on open-pit mining, obtaining shale oil by retorting shale on the ground (Li, Tang, Xue, Zheng, & Du, 2014; Qian, Yin, 2008). However, this technology has a bad effect on the environment and leads to severe resource waste for utilizing oil shale. Exploiting oil shale by in-situ method for ‘green mining’ is widely necessary in China (Kang, Wang, Cao, Liang, Chang, & Liu, 2013; Waters, Dean, Downie, Kerrihard, Austbo, & McPherson, 2009; Zoback, Kohli, Das, & McClure, 2012). One of effective method to exploit shale oil is heating oil shale in-situ underground. For instance, the in-situ conversion process (ICP technique) from Shell Company etc. used a direct heating method, and convectional heating oil shale underground by injecting superheated steam from Mining Technology Institute, Taiyuan University of Technology and constructing horizontal fracture in vertical wellbore from Chevron Company use indirect heating method (Chaudhary, Ehlig, & Wattenbarger, 2011; Hazra, Lee, Economides, & Moridis, 2013; Zhao et al., 2010). The convectional heating method contains complicated procedures with phase transition in double-media of fracture-matrix of oil shale subjected to multi-physical fields coupling including stress, fluid and temperature (Zhao et al., 2010). The characteristics of thermodynamics, solid mechanics and seepage of oil shale have been investigated separately (Hopkins, Rosen, & Hill,1998; Kang, Zhao, & Yang, 2008; Yang, Zhao, Kang, 2010; Zhao, Yang, Feng, Liang, & Kang, 2008; Zhao, Cao, Zhao, Lin, & Wang, 2008). However, it is quite difficult to solve constrained problem of each physical parameter in multi-physical fields coupling for oil shale pyrolysis."

Jan 1, 2015

By J. J. Laffin

In the pursuit of comfort and safety, the wonders of science have given us controlled heating and cooling, thus enabling us to enjoy all the aspects of present-day living to an extreme never previously •envisaged. Man's attempt to conquer the elements largely involves con-trolling the temperature around him. Without having conquered this aspect, his body energy would be consumed in trying to maintain physical comfort, rather than being invested in the explorations which have resulted in man's control over the forces of nature. The indirect methods used to obtain the most agreeable temperature environment were developed because of the natural tendency to strive for increased safety, convenience and comfort. Until the twentieth century, when heat generated by atomic fission became a reality, man's only source of heat, except for that of the sun, came from his discovery of fire.

Jan 1, 1962

By James D. Hall

THIS essay deals with the materials and methods used in the waste filling of scopes in Canadian mines, with especial reference co the methods used at the Sullivan mine, Kimberley, B.C. The author would like to thank members of the staff of the Sullivan mine for information obtained, and acknowledges material from the following publications: Waste Filling of Stopes: Information Circular 6816, U.S. Bureau of Mines. Mining Methods and Practices at Lake Shore, by Leslie S. Weldon; Trans., C.I.M. & M., Vol. XXXIX, 1936, pp. 142-202. Development and Mining (at the Mcintyre Mine), by D. E. Keeley; Eng. & Min. Journal, November, 1933. INTRODUCTION Although mining in Canada is a relatively youthful industry, many of our mines have reached a stage of extraction which requires waste filling, both as a means of support and co make possible the winning of ore that would otherwise have co be left in the mine. Fill may be used at regular intervals as one of the cycle of operations, as in cur-and-fill and square-set scoping; or it may be introduced into a completed stope co provide permanent support for overlying rock formations, and co permit mining of pillars of valuable ore. Waste fill is sorted in resuing, which is a form of cut-and-fill scoping employed in narrow veins.

Jan 1, 1937

By André Piché

"Over the last ten years, several developments have been undertaken to conceive a machine capable of carrying out simultaneously all the mining tasks in hard rock deposits: cutting, mucking, hauling, ground support and dust control.The main advantages of continuous mining over conventional drill and blast is the elimination of the cyclical nature of the actual methods. Other advantages sought are improved stability of mine openings, higher productivity, lower costs, and a cleaner and safer mining environment. Noranda has con-tributed to these developments in a major way. As a member of HDRK, Noranda participated in the development of two mechanical continuous mining machines; the TM60 and the Wirth. Noranda also undertook a development of its own based on the utilization of electricity to break rock. This technology is called plasma blasting (PBT). The concept of plasma blasting is illustrated in Figure 1.When the operating voltage is reached (18kV), the energy is released through a high current switch (500k A) into a coaxial powercable. It is then delivered to the tip of an electrode inserted into a drill hole which is filled with an electrolyte (water). When the energy reaches the electrolyte, it is instantaneously transformed into a high temperature, high pres-sure plasma that produces a shock wave capable of breaking rock(1).After initial testing of the plasma blasting technology in the lab and in the feld, two experimental platforms were constructed. The first one, a test bench, was erected at the Noranda Technology Centre in Pointe Claire, Quebec.(2)The second one is a rock breaker prototype based on a standard diesel-powered carrier (Fig. 2). Each platform was equipped with a 300 kJ pulsed-power module.In 1993, the rock breaker prototype was used for an extensive series of tests in the field. During that campaign, over 700 oversized boulders were blasted. The results of the tests demonstrated that more durable components for PBT were needed. The test bench was then used to successfully develop and test long-lasting components (probe, switch, cable, connector) that can be adapted to industrial platforms leading to the commercialization of the technology."

Jan 1, 1996

By Corrie Pitzer

Safety performance in many companies and even industries has stalled in the last decade. Accidents rates are improving but more slowly and yet, serious accidents and fatality rates are not: in fact, these rates of more serious incidents have plateaued or deteriorating. In more dramatic cases, organizations that had ?exemplary? safety statistics, suddenly had a catastrophic or multi-fatality event occurring. Popular books such as In Search of Excellence of Peters and Waterman or Good to Great of Jim Collins created many delusional ?secrets? or recipes, to achieve great performance and yet, most of those ?great? or ?excellent? companies have now declined in their performance, some dramatically and some have fallen from grace, like Fanny Mae, a company Jim Collins identified as a ?great? one, that had to be bailed out in the latest financial crisis. These organizations share several ?delusions? about managing a business, and often, these delusions are created by academics, consultants and authors of popular books about (safety) management. More damaging however is that safety management is defined by a set of key practices or axioms: a focus on human error, compliance to rules and regulations, creating consistency of systems and actions, reacting to accidents and incidents and on prevention of those, measuring safety with performance metrics and rewarding employees on those measurements. All of these axioms contain the seeds of destruction, and they create conditions and dynamics that precede the disaster - and ironically, they are all 'good things' we do in safety management. For example, a mere focus on safety in the business, and the measurement of it, create a culture of repression of mistakes and incidents, leading to a situation where the organization knows incrementally less and less of risks and risktaking behaviour - until the day it all coincides destructively! This paper discusses seven such safety delusions and how they impact on the views and safety management approaches. They are: ??The delusion of (risk) control, that risks can actually be identified, analyzed and mitigated. ??The delusion of compliance, that mere compliance to rules will safeguard the business ??The delusion of consistency, that standard operating procedures will ensure safe operations ??The delusion of predictability, that accidents and trends tell us everything about the risks of the future ??The delusion of human error, that people are the weakest link and that it can actually be dealt with through discipline and enforcement. ??The delusion of statistical trends, that safety is measurable with statistics ??The delusion of invulnerability, that we have achieved high levels integrity and capability to deal wit risks. Organizations that suffered catastrophes all share some or all of these delusions and this paper traces how these played a role in many disasters, ranging from the Titanic, Challenger, Piper Alpha, Bhopal, BP Deepwater Horizon and many more.

Aug 1, 2013

By Henry Lepp

Introduction A shaft sinking operation carried out at the Viking Yellowknife mine in the spring of 1947 presents certain features, especially as regards speed of sinking and low cost, that may be of interest to Institute members, and especially to those who are not familiar with conditions and costs in the Northwest Territories. After collaring, the inclined, two-compartment shaft was sunk 130 feet by four miners in twenty-eight days at a direct cost of only $53.19 per foot. All things considered, this is a remarkable performance, even if it does not actually establish a record. The property is at Morris lake, some forty-five miles north of Yellowknife. Formerly owned by Athona Mines (1937), Limited, it was acquired by the then newly incorporated Viking Yellowknife Gold Mines, Limited, in 1947. Surface work and diamond drilling in 1946 disclosed a number of veins and masses of quartz in a sill of diorite which lies conformably within sedimentary rocks. The sill strikes N.30°E. and dips at 70° to 85° southeast, and has a mean width of 40 feet over its explored length of 3,000 feet . Both the quartz and the diorite carry gold and are mineralized with pyrrhotite and lesser amounts of galena, sphalerite, chalcopyrite, and arsenopyrite. Of thirty-five holes drilled in the mineralized zone, the core from twenty showed visible gold. Sampling of drill cores indicated several ore shoots in the north and central parts of the sill. Assays, however, were somewhat erratic, possibly due to the fairly widespread presence of visible gold, and it was decided that the deposit could best be explored by underground sampling. Accordingly, late in 1946, plans were laid for the sinking of a shaft.

Jan 1, 1948

By R. K. Collings

"This paper summarizes research that was done at the Mines Branch, Ottawa, to evaluate samples of phosphogypsum for gypsum products manufacture. The samples were from phosphate fertilizer facilities at: Port Maitland, Ontario ; Valleyfield, Quebec; and Fort Saskatchewan and Redwater, Alberta. All samples were wet-screened, washed, filtered and calcined in a laboratory kettle at atmospheric pressure. Tests were also made at higher pressures in a small autoclave. The gypsum and resulting hemi-hydrate, being acidic, were treated before, during and after calcining with various bases. The hemi-hydrate products were checked for time of set, compressive strength and bond to gypsum wallboard paper. The results of this study indicate that phosphogypsum from each of the sources investigated has potential as a substitute for mined gypsum in gypsum products manufacture. Pilot-scale testing is recommended to confirm that the product would be satisfactory for the manufacture of plaster products on a commercial basis."

Jan 1, 1972

By A. E. Aho

"The material presented in this paper will be subject to modification as new data become available, but it is presented in the hope that it will inspire more intensive mineral exploration and geologic studies of what appears to be one of Canada's richest mineral provinces. A metallogenic province 400 by 150 miles in extent, lying mostly northeast of Tintina trench, encompasses most of the base metal deposits of Yukon, as well as deposits of other metals. Its main features are northwesterly trending arcuate fold belts, with several orogenic axes, which include most of the metamorphosed rocks, granitic intrusives and mineralization; and which are modified by regional uplifts, northwest-striking fault trenches, and lesser transverse folding and faulting.The main base metal occurrences and their regional controls are summarized briefly. Most of the replacement-type deposits are localized in late Proterozoic to early Paleozoic rocks, particularly Lower Cambrian -probably because these are the most physically and chemically favourable hosts encountered in an appropriate temperature and pressure environment; perhaps because of early age of deposition. Most of the deposits also occur near heat sources or intrusives with associated structural uplift, which has, moreover, served to expose the older rocks. They also tend to occur near known or suspected regional fault trenches, such as Tintina, Macmillan and Hess, although this relationship may be fortuitous. In detail, they may be localized in fold axes, flat-lying beds or other appropriate structural traps. Vein-type deposits are fracture-controlled and localized by dilational localfties, the competence of wall rocks and ""damming"" effects.In the Anvil district, large stratiform iron-zinc-lead replacement deposits lie parallel to gently plunging flex-ures in phyllite in a zone parallel to the Tintina trench, along the southwest flank of the arch-like Anvil batholith. About 80 million tons of massive sulphide ore probably existed before erosion of the Faro orebody, the Vangorda deposit could have been of similar magnitude before erosion and much more tonnage probably remains to be discovered in the district. The Anvil deposits may differ from others found to date in Yukon, but resemble the Sullivan orebody of southeastern British Columbia in their large size, localization in essentially non-limy peptic to arena-ceous host rocks of Proterozoic or early Paleozoic age and proximity to the Rocky Mountain -Tintina trench sys-tem. These features suggest an origin from primordial subcrustal sources.More major ore deposits, not only of lead, zinc and copper but probably of other metals as well, will no doubt be found in similar environments in Yukon or Alaska. Thus, the base metal province of Yukon offers challenging opportunities for prospecting, development, field studies and basic research."

Jan 1, 1969

By M. S. Badollet

INTRODUCTION THE DEMAND for general knowledge on asbestos fibres has increased considerably in recent years. A few publications have printed data showing some of the physical and chemical prupertie3 of asbestos, but in many cases this information is difficult to find and is seldom available when needed. During the past ten years, Johns-Manville have received many inquiries on the physical and chemical properties of asbestos fibres. Fortunately, we had some of the information in our files, and we willingly supplied the data. To help relieve this need, we have tried to present briefly in this paper some of the interesting and out-standing properties of asbestos. This information was obtained over a period of years by search of the literature and by experimental investigations. PROPERTIES OF ASBESTOS FIBRES Table I (1, 2) presents, in convenient form for easy comparison, data on the principal properties of the several varieties of commercial 'asbestos' -actinolite, amosite, anthophyllite, chrysotile, crocidolite, and tremolite. Under each variety of fibre is a brief statement describing the properties in terms of structure, mineral association, origin, etc. Some of the more important data in Table I are expanded and presented in Table II (3). SOLUBILITY OF ASBESTOS A report ( 4, 5) discussing the effects of acids and caustic on asbestos fibres was published in Germany in 1927.

Jan 1, 1951

"Developing markets for western metallurgical coal have continued to stimulate considerable exploration activity in the Rocky Mountain foothills and to influence major segments of a wide-ranging carbonization R&D pro-gram. Adjunct studies have included expanded petrographie investigations.Coal preparation has• been principally directed toward utilization of prepared small coal and was, like much of the year's combustion work, strongly influenced by concern over atmospheric pollution. Particular attention has been given to desulphurization and to the suppression of pollutants in combustion systems.In the area of non-fuel utilization of coal, interest has centered on plant nutrients and on a series of coal-based carbons which, inter alia, possess utility as filtration media.Other projects included the development of improved sampling and analytical methods, investigations into the effect of storage on coal proper-ties and R&D in solids pipelining. In addition, a significant volume of basic 'uncommitted' research has been maintained."

Jan 1, 1968

By J. Dennett, M. Faris, M. Antonio, M. Collins, N. Tuffrey, R. Ellenwood, V. Reddy

"In January 2012, AngloGold Ashanti Córrego do Sítio Mineração, with assistance from Sherritt International Corporation, commissioned a new autoclave for pressure oxidation of refractory gold concentrate at the Córrego do Sítio operation in Brazil. Start-up of the plant occurred in a few weeks and enhanced gold recovery was realized almost immediately, with 94% gold extraction achieved in carbon in leach (CIL), compared to less than 70% without pressure oxidation. This paper describes start-up and commissioning of the plant and provides an overview of plant performance over the last five years.INTRODUCTION In 2008, AngloGold Ashanti purchased the former São Bento property from Eldorado Gold, which, along with AngloGold Ashanti’s existing Córrego do Sítio mine, was renamed AngloGold Ashanti Córrego do Sítio Mineração (AGA Mineração). Later that year, the Sherritt Technologies division of Sherritt International Corporation (Sherritt) was contacted to begin batch and continuous pilot plant tests to determine the amenability of the AGA Mineração refractory gold concentrates to the pressure oxidation process. Based on the results of the batch and pilot plant tests, AGA Mineração requested basic and detailed engineering studies to be conducted by Sherritt, eventually leading to commissioning of the plant in January 2012. AGA Mineração’s plant is located in southeastern Brazil in the state of Minas Gerais, near the city of Belo Horizonte. AGA Mineração`s Phase 1 mine plan covers three sites in the Laranjeiras, Carvoaria Velha and Cachorro Bravo ore bodies, and is designed to process 60,000 tonnes of refractory gold concentrate per year to produce 140,000 ounces of gold per year with an 11 year life of mine (AngloGold Annual Financial Statements, 2010). Recovery of gold at AGA Mineração is based on Sherritt`s pressure oxidation technology for refractory gold concentrates (Berezowsky et al., 1991; Collins et al., 2011a; Collins et al., 2011b). This process had previously been applied to the recovery of gold at the São Bento site (Carvalho et al., 1988; de Silva et al., 1989), in a plant that was operational between 1986 and 2007 (Silva et al., 2004)."

Jan 1, 2017

By J. M. Whatley

"IntroductionFEW COUNTRIES equal Canada in the diversity of its mineral output, the range of size of its mine operations, and the extremes of climatic and topographic conditions under which its mining is carried out. Camps large and small are scattered over thousands of miles, some served by excellent communication lines, many in remote regions of the north. Common to most of the deposits is that they are worked by underground methods, and rely on adequate hoisting installations for the success of their operations.Hoisting in some form •pre-dates all other mechanical operations in mines and the hoist remains one of the most important pieces of equipment at the average mine. It provides the single line of communication along which must pass the men and materials to mine the rock, and in turn carry the ore to a place for refinement.Development of Mine Hoists in CanadaCanadian designed hoists were first built and •placed in operation about the year 1880 and have since developed in pace with the rapid growth of the Canadian mining industry. Early machines were all of the steam or compressed-air driven types, of light construction and driven by two duplex slide-valve open-frame type engines. As their application and size increased, designs became more rugged and more efficient."

Jan 1, 1955

By Himmelman. Nicholas P.

In this paper, the hardware foundations and data collection methods of a real time collision avoidance system for electric surface mining rope shovels are described. The primary goal of the system is to help a shovel operator avoid accidentally colliding the shovel?s dipper with either a nearby haul truck or the shovel?s tracks. To achieve this goal, the system requires complete and precise knowledge of the shovel?s geometry and movement, as well as the location of any nearby haul trucks. This paper describes the subsystems created to acquire this necessary information. This system is unique in that all of its components are mounted solely on the shovel and that it is designed to be easily retrofitted to a shovel without significant modifications.

Oct 1, 2009

By C. E. Baltzer

This paper highlights the electric power situation in Canada, and introduces brief explanation of the salient differences between electrical practice in the United States and Canada. The availability of bask energy in the two countries is touched on, also the hydro versus thermal outlook as applying to Canada. De-v2lopment of thermal-electric power is dealt with in some detail, followed by Canada's thermal-electric power requirements, present and future. The fuel requirements for steam-electric generating plant are assessed on the basis of a survey recently made, and the location and size of the major thermal plant operations are given. Fuel contractual obligations on the part ?of suppliers and consumers are mentioned. Finally, an opinion is expressed in regard to the types of f.uel in ?demand on a regional basis with emphasis on the need for coal in the several areas dealt with.

Jan 1, 1958

By Thomas H. Heine

"The Rabbit Lake uranium deposit is located at 58° 11’00”N.. 103°42'36""W., close to the west side of Wollaston Lake, and approximately 800 km north of Saskatoon. The orebody is hosted by Aphebian Wollaston Group rocks, initially deposited as a series of shallow-water marine sediments consisting, in part, of carbonates and possible saliferous petites. Metamorphism during the Hudsonian Orogeny, peaking at about 1850 Ma, recrystallized the sediments to upper amphibolite grade paragneisses. This was accompanied by partial anatexis. The waning stages of Hudsonian orogenesis appear to be marked by minor granitic intrusive activity.The post-Hudsonian period was marked by a long interval of physical and chemical erosion, resulting in the unroofing of the Wollaston metamorphic complex. The entire region underwent extensive lateritic weathering under tropical to subtropical conditions. Carbonates were especially vulnerable and, in the Rabbit Lake area, suffered extensive solutioning with accompanying formation of collapse breccias. Old zones of weakness also underwent periodic reactivation.It was during this period that uranium was leached from the surrounding meta-sediments by oxidizing meteoric waters, and transported into the karsted and fractured rocks of the Rabbit Lake doline.Athabasca Group sediments eventually covered the deposit, their diagenesis taking place at about 200 °C and 900 bars. This allowed the partial to complete recrystallization of the initial mineralization, resulting in a minimum age of 1281 ± 11 Major ""first""-generation pitchblende. Periodic fault/fracture reactivation modified the hydrologic regime within the deposit, resulting in episodic mobilization and recrystallization of pitchblende and other uraniferous species. This is clearly shown in the open pit at the present time: uranium is being mobilized and recrystallized on damp pit walls as bayleyite and liebigite due to the modification of the hydrologic system by mining activities.The uranium mineralization occurs mainly as fracture fillings, coatings, and impregnations within breccia zones and intensely altered metasediments. Lesser mineralization is intimately associated with phyllosilicates which form the matrix of a carbonate-col/apse mega-breccia. The primary ore mineral is pitchblende, consisting of five generations, and from which a large suite of secondary uraniferous minerals have formed. On a gross scale the metal content of this deposit appears to be simple, consisting almost exclusively of U, but minor Ni, As, Cu, Se, Fe and Co are also present. The eastern limit of the mineralization is defined by a vertically-dipping microgranite dyke - breccia complex, containing high-grade uranium values. The orebody is truncated to the west and at depth by the Rabbit Lake reverse fault. Minor mineralization occurs as fracture fillings in unaltered plagioclasite in the footwall of the ore body. Precipitation of uranium from solution could have taken place by a number of processes. A mobile reductant (methane, carbon dioxide, etc.) may have been generated from graphite present in some of the host rocks of the orebody. Sulphides are also a common accessory and may have aided in the formation of a reducing environment. Phyllosilicates may have acted as adsorbants for uranium, allowing for its fixation. This metal has also been incorporated into the phyllosilicates themselves."

Jan 1, 1986