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By F. W. Gray

Foreword: It is not my purpose, in this address, to write the history of the Geological Survey of Canada, which has from time to time been reviewed by the officers of the Survey itself, and by men more competent than myself to handle so large a subject, but rather to set out some of the reasons for the regard in which the Survey is held by our Institute, the body best qualified to speak for the mining men of Canada. And, a further purpose is to publish the desire of our Institute that the work of the Survey shall be maintained at the highest pitch of efficiency the resources of our country. will permit, because to scrimp expenses on the Survey is 'to save at the spigot and lose at the bunghole." A historical examination of the grounds on which it may be asserted the Geological Survey has been, and still is, of fundamental economic value to our country, discloses a prescience on the part of the forefathers of Canada, calling for our admiring gratitude, and reveals a unanimity among the real leaders of Canadian thought, on the value of geological knowledge, that is impressive in its continuance dawn to this date. There seems always to have been before our people the realisation that large stretches of Canada are unfitted for agricultural settlement, and that our glaciated areas, the barrens and tundra of the North, and our extensive mountain ranges, had promise of compensating mineral content which the geologist and the prospector, labouring together through the years, would disclose. The Geological Survey is one of Canada's oldest public services, distinguished by an unimpaired tradition of honourable and useful labour. Founded in 1843, under William Edmond Logan, not yet 'Sir William', one year after the Act of Union, it was directed by him until 1869, or into the early years of Confederation, so that the early years .of the Survey were also, politically, the formative years of Canada, as we know her today.

Jan 1, 1932

By M. Yavuz

As a branch of Operations Research, decision making is a widely used application in both science and social sciences. There are many different methods developed to solve decision making problems in the literature. In this study, Fuzzy Analytic Hierarchy Process (AHP) method is performed for the selection of reclamation project selection in an open pit mine and the optimal solution of the problem is investigated. Different reclamation project alternatives are prepared for an open pit mine, which continues to its production activities in magnesite sector in Turkey. The data obtained from Magnesite Cooperation is used in the application of the method. A decision-making process is prepared as considering the project alternatives for the purpose of selecting the most suitable reclamation project. The entire criteria that affect the decision-making process are identified and transformed into a hierarchical structure. The problem is solved by using Fuzzy AHP method developed according to this structure. It is found that Fuzzy AHP is a method that may help decision-makers in solving different decision-making problems in mining.

Aug 1, 2013

By V. S. Melamud, A. G. Bulaev

"Sulfide ore processing is characterized by significant losses of metals, for example, with flotation tailings. Therefore, flotation tailings can present an important source of metals. The treatment of flotation tailings is a technological issue due to low content of valuable metals (e.g. copper and zinc) and high iron content. The goal of the present work was to investigate extraction of base metals and gold from old flotation tailings containing 17% iron, 0.26% copper, 0.22% zinc, and 0.7 g/t gold. Chemical leaching in columns with 0.5 to 10% sulfuric acid solutions and bioleaching in air-lift percolators were used for the extraction of base metals. 1% H2SO4 provided high extraction of base metals and best selectivity. Recovery of copper and zinc reached 35% and 40%. Increasing H2SO4 concentration did not lead to significant increase in base metals extraction, but led to increased iron concentration in the pregnant solutions. The 1% H2SO4 leaching solid residues were used for further experiments. Acid leaching and bioleaching did not result in significant increase in base metals recovery. Leaching of the residue with 10% H2SO4 provided extraction of 4% copper and 20% zinc, and bioleaching for 100 days provided extraction of 16% copper and 12% zinc. The recovery of gold by cyanidation from the flotation tailings, the 1% H2SO4 leaching solid residue and residue of two-step acid leaching were 50, 49, and 65%, respectively. The results suggest that acid leaching can be effective approach for treatment of old flotation tailings.INTRODUCTIONAbout 80% of base metals (copper, nickel, zinc) are produced through pyrometallurgical treatment of sulfide ores. Mining and metallurgical treatments of sulfide ores are presently characterized by significant losses of non-ferrous and precious metals into the various wastes. For example, flotation of sulfidic ores yields formation sulfide flotation tailings. These wastes pose a problem not just because of their sheer volume, but some of them may affect local ecosystems. Nowadays, mining and metallurgical wastes can be considered as technogenical source of base metals."

Jan 1, 2016

By A. J. Petrina

"At Craigmont Mines Limited, Merritt, B.C., tests were begun in March, 1965 to evaluate the use of shotcrete as a method of ground support m development headings; previously, ail drifts had. required support, which was accomplished mainly by timber and occasionally by the use of rockbolts. The tests demonstrated conclusively the effectiveness of shotcrete for supporting Craigmont's ground. Gradually, the use of timber for ground support was virtually eliminated in favour of shotcrete. This paper describes the equipment used, the operation of the equipment, pertinent cast data and opera ting details. Also discussed are other uses developed for the shot-creting equipment, the use of reinforcing bar rockbolts, and a method used at Craigmont for lining long vertical ore passes with steel plate and concrete as part of the raising cycle."

Jan 1, 1968

By M. A. Kessick

Current treatment and disposal procedures are compared for clay slimes resulting from the extraction of Alberta oil sands, the extraction of Florida phosphate matrix, the recovery of diamonds from kimberlite deposits in South Africa, the recovery of kaolin from clay deposits in southwest England and the upgrading of bauxite ore. Published research in the area is reviewed, and common trends which are emerging in the disposal of clay slimes are discussed.

Jan 1, 1978

By F. L. Casey

"Part 1 – Published Papers Baria, G., and Boshkov, S., ""Insights into Undercuttingin Block Caving"", Proc. 5th Rock Mech. Symp.,Mines Br. - Information Canada, 41-58, 1970.Barron, K., Coates, D. F., and Gyenge, M., ""ArtificialSupport of Rock Slopes'', Mines Branch ResearchReport R228, July, 1970.Barron, K., ""Criteria for Brittle Fracture Initiation inand Ultimate Failure of Rocks and Their Applicationto Fracture Zone Prediction"", Proc. 2ndCongr. Int. Soc. Rock Mech., Belgrade, 1970, 3-37.Bauer, A., and Calder, P. N., ""Projectile Penetration inRock"", Proc. 5th Rocle Mech. Symp., Mines Br. -Information Canada, 157-170, 1970.Bauer, A. M., ""Site Development and Rehabilitation ofPits and Quarries"", Canadian Mining Journal,Vol. 91, No. 7, 77, July, 1970."

Jan 1, 1971

By Y. Q. Li, X. H. Long

In this work, structural and electronic properties of smithsonite (ZnCO3) and cerussite (PbCO3) as the typical lead-zinc oxide minerals is simulated by means of DFT. The calculated results could be concluded as: (1) The density of states (DOS) of Zn atom in ZnCO3 is nearer to the Fermi level than that of Pb atom in PbCO3, suggesting that the Zn atom of ZnCO3 is more active and easier to interact with water molecules and hydroxyl ions. Smithsonite, therefore, could be more readily depressed in the flotation process. (2) The bond population value of Zn-O (0.23) and C-O (0.92) in ZnCO3 is obviously larger than that of Pb-O (-0.01) and C-O (0.85) in PbCO3, indicating that the covalent characteristic of ZnCO3 is stronger than that of PbCO3. (3) It is shown that the charge of Pb (+1.32e) in PbCO3 is more positive than that of Zn (+1.22e) in ZnCO3, suggesting that cerussite is easier to interacting with HS- compared with smithsonite in the flotation process. In summary, the structural and electronic property of smithsonite is completely different with cerussite, leading to the difference of their flotation behaviour.

Jan 1, 2015

By D. Stone, N. J. Aslin, W. Webb

In today's modem copper electro-refineries, increasingly higher average current densities are being employed. With these increases many refineries are approaching their limiting current density. The nearness of the average operating current density to the limiting current density has placed increasing emphasis on the need to maintain an even current distribution. This paper explores the importance of maintaining even current density and discusses the factors, processes and practices that are necessary to achieve and maintain high quality production at high operational intensity.

Jan 1, 2005

By Dawei Yu, Kinnor Chattopadhyay

In the nickel industry, molten slags produced from a Pierce-Smith converter contain significant amounts of valuable metals in the forms of oxides and physically entrained matte droplets. A slag cleaning step, which takes places in an electrical slag-cleaning furnace, is therefore required to recover the valuable metals as a common practice. Utilization of a waste material from aluminum industry (i.e. spent potlining) as a flux to improve the slag cleaning in terms of both the metal recovery and the operation efficiency was studied by simulation with FactSage program. Results show that the addition of SPL could substantially reduce the slag viscosity due to its fluoride values, thus accelerating the settling of matte droplets. The carbon value in the SPL could also help increase the metal recovery by reducing the valuable metal oxides followed by settling.

Jan 1, 2015

By A. C. Stevenson

"There are many critical application issues that affect all AC drives, but there are several that are absolutely mandatory for pulse width modulated (PWM) AC drives. If these rules are not followed, the drive system will have insulation, bearing EMI or noise problems. Pulse Width Output VoltageFigure 1 shows the output current of a typical pulse width modulated (PWM) drive. This is, of course, not a clean sine wave thus will have a lot of very significant harmonics. In fact, the harmonic spectrum is directly related to multiples of the carrier switching frequency plus side bands related to the basic output frequency. A typical spectrum for a PWM source bridge switching at 5 kHz is shown in Figure 2. Notice that the spectrum has multiples of the 5 kHz switching frequency and the number of side bands gets larger as the harmonic number increases.IGBT Switching TransientsWhenever we have PWM inverter switching, voltage transients are formed that propagate (usually at about half the speed of light) down the power cables to the motor just like in a radio frequency transmission line. If we do not terminate these transmission lines (motor cables) properly, the voltage pulses will be reflected when they reach the motor end and will be transiently increased up to twice their original amplitude.This transient voltage rise, shown in Figure 3, is important for three reasons:1. Insulation Voltage Stress — Higher voltage stress in the motor connecting cables and motor insulation will lead to a shorter insulation lifetime. If any of the voltage transient peaks exceed the insulation corona discharge level (partial discharge level), the insulation will gradually degrade with each voltage pulse. When it has been sufficiently degraded, it will then fail.Most new “inverter rated” motors have triple layer insulation which has a 1600 to 2000 volt partial discharge level. This will make them suitable to withstand the double voltage peak transient from a 600 volt inverter. It is wise to make sure of this fact, since a “standard” induction motor will only withstand about 1200 volts. Use of a standard motor in this application would shorten its life drastically. This can sometimes be as little as a matter of hours."

Jan 1, 2000

By Charles Amoah

Abosso Goldfields Limited has been optimizing the comminution circuit at the Damang Mine Operation for the treatment of 100% primary ore. The optimization process started at a base rate of 343 tph when treating primary crushed primary ore, and was increased to above 600 tph with partially crushed primary ore. Abosso Goldfields engaged Orway Mineral Consultants (OMC) to assist with the optimization process in 2009 and the two companies have been working together since, to further refine the process. Continuous improvement was achieved through crushing circuit modifications, changes in operating processes and grinding control system utilization. This paper discusses the improvements developed for the increase in milling capacity and improvements in final product size.

Jan 1, 2012

By Owen Matthews

Introduction For the past year and a half, the mill of Cochenour Willans Gold Mines, Limited, McKenzie Island, Ontario has been roasting arsenopyrite-gold concentrates, prior to cyanidation, by means of a roaster employing techniques that are new and novel. The roaster is known as the Dorrco 'fluo-solids reactor', and the technique as 'fluidization'. The reactor has demonstrated its ability to roast a flotation concentrate containing arsenopyrite, pyrite, stibnite, small quantities of other sulphides, and some lime silicates and carbonates, yielding a calcine consisting mainly of porous iron oxide, plus the gold values. This calcine is readily amenable to cyanidation. Bulk shipments of concentrates to a distant custom smelter, as practised prior to this installation, has thus been eliminated, with appreciable savings in smelting charges, freight costs, and interest losses during shipment and smelting. This is the pioneer installation of fluo-solids roasting at a Canadian mill and up to the present performance results have not been published. It is the purpose of this paper to present the information now available for the benefit of other millmen who may be confronted with identical or similar problems to those encountered and solved at Cochenour Willans.

Jan 1, 1949

By V. Maazallahi, A. Rouleau, A. Saeidi

"The geometry of the terrain topography before and after the failure are the essential factors for analyzing a landslide and for the design of remedial works. This paper presents a method to determine these factors, considering that the determination of the slide surface profile is difficult and costly using traditional methods and the pre-slide topography data is often not available. The presented method to locate the 3-dimensional geometry of the slide surface is based upon determining the slide surface in 2- dimensional vertical sections. This method utilizes post-slide topography of the area to determine the pre-slide topography and uses equations to estimate the pre-slide situation using a statistical process applied to points located on the sliding mass. This method is tested on the Maskun landslide in Iran. The results indicate the applicability of the proposed method to obtain the key factors for the back analysis of a landslide in a cost effective manner.INTRODUCTIONProbably the most reliable method of determining the strength of soil and rock mass is to back analyze a failed or failing slope (Caia et al. 2007; Wyllie & Mah, 2004). This method is used in geotechnics for estimating geotechnical parameters of the rock and soil mass (Sakurai et al., 2003; Frayssines and Hantz, 2009; Cepuritis et al. 2010), but it requires that the failure mode is well established and that there is complete and precise information available on the slide surface and the sliding mass (Sjöberg, 1996). Measurement of the slope profile before failure provides the basic information required for a back analysis (Hock & Bray, 1981). The post-slide topography is another key factor. The back analysis process for determining the actual strength parameters of soil or a decomposed rock mass after a landslide requires knowledge of the sliding mass geometry, both before and after the sliding event. Many studies are reported in the literature about the application of back analysis for determining geotechnical and geomechanical parameters of rock and soil mass (Sakurai et al., 2003; Cepuritis et al. 2010; Frayssines and Hantz, 2009, Hussain and Stark, 2011), but they generally present little information about the geometry of the slide surface, and the weight of rock and soil mass that slid, although these factors are the most important parameters for back analysis process. Liang and Xue-song (2012) determined the slip surface having the minimum factor of safety (called critical slip surface in deterministic analysis of slopes) and the slip surface with the minimum reliability index (called critical reliability slip surface), but they have not considered the actual profile and geometry of the slide surface. Rocscience (2013) proposes the back analysis option in the Slide software for slope stability study, but it requires an imposed slide surface as input; alternatively, one can estimate by a finite element analysis the surface with the minimum factor of safety. However, this estimated surface is very likely different from the actual sliding surface, considering the uncertainties in input data of the finite element method."

Jan 1, 2015

By John R. Hayes, Kebbi A. Hughes, John Rowson, Peter E. R. Blanchard, Jeremiah C. Beam, Andrew P. Grosvenor, Arthur Situm

Uranium ore bodies contain elements within mineral phases that need to be disposed of responsibly. Solid waste can be placed in a tailings management facility (TMF) to contain the waste elements and limit interactions with the environment. It is important to understand how the chemistry of the tailings evolves throughout the lifetime of the operations that feed the TMF and after the site has been decommissioned. The objective of our collaboration with Orano Canada was to study how the tailings from the TMF located at McClean Lake, Saskatchewan change over time. This manuscript discusses our use of X-ray absorption spectroscopy (XAS) and X-ray microprobe to study the fate of Mo and Ca in the tailings. Mo is considered an element of concern (EOC) and it is necessary to determine if a stable solid Mo-bearing species forms. Thermodynamic modeling suggested that aqueous Mo would precipitate over time as powellite (CaMoO4). Comparing Mo K-edge XAS spectra from the solid tailings to the aqueous Mo concentration in the pore water showed that powellite did form and that this did result in a decrease in the aqueous Mo concentration over time. Further, it has been proposed that Ca2+(aq) can react with bicarbonate ions in the pore water and precipitate as calcium carbonate (e.g., CaCO3). This reaction would limit the aqueous bicarbonate present in the tailings that could react with uranyl ions to form soluble uranyl-carbonate complexes. We have identified several trace Ca-bearing species, including carbonates, in the tailings using XAS and X-ray microprobe.

Jan 1, 2020

By Louise Corriveau, Bronwyn Azar, Valerie A. Jackson, Luke Ootes, Jeff Harris

We use the results of new bedrock mapping, combined with geochemical point data and airborne radiometric data (in particular equivalent uranium concentrations) to help determine which geological units in the Paleoproterozoic Great Bear magmatic zone (GBmz) contain elevated uranium. The data collectively indicate that the highest primary uranium concentrations are in equigranular granites and subvolcanic/volcanic porphyries. Notably, these rocks host the majority of known uranium-bearing deposits and/or prospects in the GBmz. We speculate that the uranium in these deposits/prospects was derived from nearby, uranium-enriched rocks and was mobilized by much younger, circulating hydrothermal fluids. Sedimentary rocks of the Thelon and Dismal Lakes groups unconformably overlie the GBmz and are known to host unconformity-type and sandstone-hosted uranium prospects. Most likely, the uraniumenriched rocks of the GBmz acted as a uranium donor to these overlying sedimentary basins. The method of investigation employed in this study may be applicable to other ‘granitic’ terrains in order to identify regions with favourable rocks for uranium exploration.

Jan 1, 2013

By Marcel Vallee, D. C. Gagnon, C. CARBONNEAU, P. ST-JULIEN

The Magdalen Islands archipelago, a cluster of fifteen islands, is located near the centre of the Gulf of St. Lawrence on the thickest portion of the Carboniferous Fundy Basin of the Maritime Pro vinces. The bedrock of the Magdalen Platform includes a thick succession of evaporites of Visean Age, occurring as a series of thickenings, ridges, domes and diapirs reaching a probable vertical thickness of close to 6000 m. The emplacement of 1hese salt structures by flowage has much dislurbed 1he SlrOligraphic sequence of the rocks of the Windsor Group, particularly 1he Havre-aux-Maisons Formation. Subsequent tectonic movemenl has broken the overlying Cap-auxMeules Forma1ion info an assemblage of panels and blocks now slightly tilted. Following detailed gravimetric surveys and more than 30,000 m of diamond drilling, SOQUEM has discovered, at various dep1hs, seven salt domes on four of 1he main islands of the archipelago. These evaporite bodies generally are localized near the cemre of complex anticlinal struclUres where diapiric movements and faulting have disturbed the original stratigraphic succession. At Rocher du Dauphin near Grosse 1/e, in 1he northern part of the archipelago, Seleine a SOQUEM subsidiary is developing a mining complex with an annual capaci1y of 1,250,000 1onnes of deicing salt for 1he Canadian and Eas1ern United Swtes marke1s. The stan of operations is scheduled for April 1982.

Jan 1, 1984

By Michel Aubertin

Les rejets miniers sont communément utilisés, depuis plus de 60 ans, comme matériau de remblayage des chantiers souterrains. Les roches stériles et les rejets de concentrateur sont employés comme remblais car ils sont disponibles sur les sites miniers à un coût réduit pour aider au support de terrain. Le remblayage des ouvertures est également avantageux car il permet de réduire la quantité de rejets entreposée en surface. Dans les mines souterraines, le remblai des chantiers doit aider à maintenir un espace de travail sécuritaire, tout en favorisant la récupération du minerai et le contrôle de la dilution. Il est alors essentiel d'évaluer précisément les pressions exercées par le remblai sur les murs et sur les barricades installées près de la base des chantiers. Dans cette présentation, des solutions existantes pour évaluer les pressions dans les chantiers sont brièvement revues. Les auteurs présentent ensuite des solutions analytiques récemment développées à cette fin, qui permettent de tenir compte du transfert des contraintes du remblai aux parois des chantiers et des galeries. Les solutions proposées, qui sont basées sur la théorie de l?effet d?arche, prennent en compte l'influence de la géométrie des ouvertures et de la position des barricades. La méthode de calcul permet aussi de calculer l?effet des pressions d?eau pour un remblai partiellement ou totalement submergé. Les solutions s'appliquent au cas d?un remblai récemment mis en place, alors que l?effet de la pression interstitielle ne peut pas être négligé, et aussi à plus long terme sous une condition drainée. Des résultats expérimentaux et des simulations numériques sont utilisés pour valider les équations proposées. Les résultats analytiques et numériques montrent notamment que la pression totale sur une barricade peut être grandement augmentée par la pression d?eau, tandis que la contrainte effective peut être réduite par les pressions interstielles (par rapport à la condition drainée ou sèche). On discutera aussi des implications pratiques de ces résultats pour l?application des remblais souterrains.

Nov 1, 2008

By R. Al-Hent, M. Aissa, J. Asfahani

"This paper presents regional radiometric gamma-ray spectrometry maps of Syria for total radioactivity (Ur) and surficial concentrations of equivalent uranium (eU). The maps were created by merging airborne and ground-based gamma-ray spectrometric survey datasets. On the regional radiometric eU map, eU anomalies are closely related to either phosphate and/or glauconite deposits. The Ur and eU maps delineate the boundaries of three phosphate deposits, close to the Palmyrides ridge, in the northern part of the Coastal Range and Syrian Desert. Scattered occurrences of uranium mineralization in other phosphate formations are attributed to secondary chemical and physical processes, rather than primary accumulation.RÉSUMÉ Cet article presente des cartes regionales radiometriques de spectrometrie gamma de la Syrie pour la radioactivite totale (Ur) et les concentrations en surface de l’equivalent en uranium (eU). Les cartes ont ete creees en combinant des ensembles de donnees, aeroportees et au sol, de releves de spectrometrie gamma. Sur la carte regionale radiometrique eU, les anomalies eU sont etroitement reliees aux gisements de phosphate et(ou) de glauconite. Les cartes Ur et eU delimitent les limites de trois gisements de phosphate, a proximite de la crete des Palmyrides, dans la partie nord de la chaine cotiere et du desert de Syrie. Des dispersions de mineralisation d’uranium dans d’autres formations de phosphate sont attribuees a des procedes chimiques et physiques secondaires, plutot qu’a une accumulation primaire."

Jan 1, 2016

By Renliang Shan

Site conditions of China?s coal roadways are complex and changeable, and scientific classification of them is the fundamental basis for coal roadway support design, with great significance for ensuring proper roadway service. Upon analysis of the issues, a commentary regarding the research progress on classification of the stability of rocks surrounding coal roadways in China has been achieved from the point of view of classification methods and indexes. The shortcomings and applicable scope of rock stability classification methods related to coal roadways have been analyzed. It has been asserted that combining artificial neural networks with fuzzy mathematics, combining fuzzy mathematics with grey theory, applying new avenues such as support vector machine algorithms or unascertained average classification, and making classification indexes more scientific are future directions for development of rock stability classification for coal roadways.

Aug 1, 2013

By N. Katsikaros, A. Lewis-Gray, P. Richards

"To optimize gold recovery in complex leach-to-electrowinning processes, Gekko Systems developed the Gekko resin exchange column (G-REX) as an intermediate step, using a highly gold-selective resin to isolate contaminant metals. The AuRIX®100 resin produced by Purolite is licensed exclusively to Gekko, with the G-REX column designed specifically for this resin. Operational experience has been gained at the Castlemaine Goldfields Ballarat gold mine. In near-continuous operation since 2008, the Ballarat plant treats unclarified concentrate leach solution. The extension of this technology to higher throughputs and more complex chemistry is discussed.RÉSUMÉ Afin d’optimiser la récupération de l’or dans des procédés complexes impliquant la lixiviation suivie de l’extraction électrolytique, Gekko Systems a développé la colonne Gekko de résines échangeuses d’ions (G-REX) comme étape intermédiaire, à l’aide d’une résine hautement sélective pour la récupération de l’or qui permet d’isoler les métaux contaminants. Gekko détient la licence exclusive pour la résine AuRIX®100 produite par Purolite, et la colonne G-REX a été spécifiquement conçue pour cette résine. C’est à la mine d’or Ballarat de Castlemaine Goldfields que l’expérience opérationnelle a été acquise. L’usine de Ballarat, en exploitation quasi-continue depuis 2008, traite une solution concentrée non clarifiée de lixiviation. L’extension de cette technologie à des capacités supérieures et à une chimie plus complexe est examinée."

Jan 1, 2017