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By A. Hynes, T. Skulski, D. Francis

The Archean volcano-sedimentary succession in the LG-3 area has undergone two phases of deformation and has been metamorphosed to upper greenschist and amphibolite facies. Marine, fine-grained sediments and mafic pyroclastics comprise the lowest observed stratigraphic unit. These sediments are overlain by a thick sequence of submarine basalts and minor basaltic andesite. The lavas are characterized by high Al/Al+Si, Ti values, low Mg numbers and flat REE profiles (lOx chondrite). A sedimentary prism of coarse elastics which was deposited close to an exposed plutonic highland, overlie the volcanics. Massive lavas of basaltic andesi te and associated volcano-sediments comprise the uppermost stratigraphic unit. These lavas are characterized by high Mg numbers, Ni, Cr, LREE (lOOx chondrite) but low Ti, Al/Al+Si and HRee. The supracrustal rocks were intruded by tonalites and tonalitic gneisses.

Jan 1, 1984

By Kenneth L. Norris

Stonegate Agricom Ltd. is currently conducting exploration and development drilling of the Paris Hills Phosphate Project (Paris Hills Project) located in Bear Lake County, southeastern Idaho, 3.2 km west of the towns of Paris and Bloomington, Idaho. The project is located adjacent to a highway and 19 km by paved highway to Montpelier, Idaho where the Union Pacific Railroad system is located. Power and water are available locally. The nearest metropolitan centre is Salt Lake City, Utah approximately 225 km by road to the south-west of the property. The Paris Hills Project encompasses an area of approximately 856 hectares. Property holdings consist of three (3) patented lode mining claims and 16 contiguous fee parcels (some with federal phosphate leases). Active open pit phosphate mining operations are located in surrounding counties in south-east Idaho and are owned and operated by Agrium Inc., Monsanto Company and J.R. Simplot Company. The Paris Hills Project is located near the centre of the Western Phosphate Field which constitutes the most extensive phosphorite beds in the United States. Phosphate beds of the Western Phosphate Field occur within the Phosphoria Formation of Permian age and extend over an area of more than 350,000 km2 including extensive areas of Idaho, Utah, Wyoming and Montana. At Paris Hills the phosphate mineralized beds occur in the overturned limb and the horizontal limb of the Paris Syncline. Grades and thicknesses in both the western overturned limb and the eastern horizontal limb of the anticline are similar. The vast majority of potential mineralization occurs in the horizontal limb which underlies most of the property holdings. Mineralization in the overturned limb has a strike length of over three (3) kilometres and extends from the surface to a depth exceeding 300 m depending on location along the north-trending strike of outcrops. Depths of the horizontal limb range from surface along the north side of Bloomington Canyon to estimated depths of 915 to 1,035 m at Paris Canyon. The property contains an Inferred resource of 109.6 million tonnes at 23.6% P2O5 over two mineralized horizons. The phosphate zones have a strike length of over 3 km and extend from surface to a depth of at least 900 m. Drilling commenced late in the 3rd quarter of 2010 and is planned to continue through 2011. The drilling was planned to target an area of potentially higher grade phosphate mineralization and better define and upgrade the current resources.

May 1, 2011

By J. W. Bawden, J. Nantel

"The mine operator has two prime objectives when he operates a mine: (l) the mine must be safe, and (2) the mine must operate with the lowest possible costs. The operator constantly faces a dilemma; if he is over cautious with regard to safety, his costs may be very high, and if he is over-zealous in trying to reduce costs, the safety of his operation may be jeopardized.Modern bulk mining methods rely heavily on high productivity non-entry stoping techniques (e.g. open stoping, VCR, etc.). Such techniques have the advantage of removing the operator from the active and sometimes dangerous mining face and ofminimizing costly development. On the other hand, this generally results in a certain loss of flexibility in following irregular ore-waste contacts. If stopes are opened too large and/or are inadequately supported, severe dilution with resulting escalating costs usually results. If initial access drift support is inadequate for latter mine induced stresses high rehabilitation costs may also be incurred.Optimization of stope dimensions should logically occur as part of a general mine rock engineering program, within the over-all mine planning context. The same program should help highlight those areas where drift rehabilitation may be a problem.Whenever successful mining is performed, rock engineering is being applied, either by design or by chance. The cost implications of planned practical rock engineering as an integral part of mine planning and design can be very significant to the ultimate mining ""bottom line"". At Noranda Minerals Inc. allowable stope dimensions are derived using a combination of numerical stress analysis and empirical design techniques. This paper discusses the use of the above techniques and their limitations as tools for rock mechanics based stope dimension optimization. The potential cost implications of such design efforts within the general mine planning context are also addressed."

Jan 1, 1989

By G. Molloy

The purpose of this paper is to demonstrate the value of applying continuous improvement, in particular 5S and standard work, in an underground environment. 5S and standard work are two aspects of Lean manufacturing that have been applied in many industries. At Vale Canada Limited, the focus is to first stabilize the process, commonly through the use of 5S, standard work and other continuous improvement techniques. In parallel with building an engaged workforce, these approaches aim to incrementally stabilize and improve a process. 5S is an employee-driven, systematic methodology to reduce waste in all its forms through attaining, maintaining, and improving workplace organization. Identified as a foundational part of any improvement process, 5S aims to remove wastes that impact on the overall efficiency of the area. Standard work is used to formulate a common approach to how tasks are carried out to ensure consistency. Standardization involves identifying, establishing, and following the best method. The aim is to eliminate the variation that can occur when there is not a pre-defined established standard. Demonstrating the value of 5S and standard work in an underground environment will be achieved by first understanding the overall concept of Operational Excellence and continuous improvement as practiced within our operations. The paper will then cover a real application of 5S and standard work within the underground environment at Thompson, Manitoba.

Aug 1, 2013

By Ken J. Brouwer

Stillwater Mining Company commenced construction and development of the East Boulder underground mine in 1998. This new PGM mine is situated adjacent to the East Boulder River approximately 35 miles south of Big Timber, Montana. Project planning and development incorporated detailed collaboration between the regulatory agencies, concerned citizens and mine personnel. A unique ?good neighbour agreement? was established with a local environmental group who have become actively involved in the review of ongoing site development and the implementation of environmental and compliance monitoring. Environmental management systems allow for integrated management of tailings, waste rock and water in order to minimize surface disturbances and to prevent adverse impacts to the East Boulder River. Long-term site development plans contemplate implementation of comingled waste rock and paste tailings. Water management capabilities allow biological treatment of all excess mine water in order to reduce nitrogen loadings prior to land application disposal by means of spray evaporation, snow making and land application. The comprehensive waste and water management plans have also been integrated with staged mine development and interim reclamation requirements.

May 1, 2002

By Douglas C. Fraser

"Geophysical data are often presented on maps, sections or profiles with minimal data processing. A common example is magnetic data, in which the diurnal-free raw readings are merely contoured on a map. Other examples include profile presentation of VLF-EM data, IP pseudo-sections and airborne EM anomalies which may be shown on a map with only the measured amplitudes indicated.In recent years, efforts have been directed to the portraying of data in more useful forms. A number of algorithms (i.e., manipulative procedures and equations) have proven to contribute significantly to the usefulness of geophysical data. Some can be applied manually; others are sufficiently complicated to require a computer. Some merely alter the data to a more useful geometric form without altering the units. Others yield quantitative estimates of source body parameters such as conductivity and shape. Several examples follow:1. A simple algorithm is in common use which transforms noisy non-contourable VLF-EM data into less noisy contourable data. The input is the dip angle in degrees or per cent and the output is also in these same units.2. A simple algorithm has recently been developed which allows multi-level dipole-dipole IP data to be contoured on a map. Again, the units are not altered.3. A relatively complicated algorithm is in common use which transforms non-contourable height-sensitive helicopter EM data into contourable resistivity data,4. An algorithm has been recently developed which transforms non-contourable height-sensitive EM data into contourable weight per cent magnetite.The purpose of all the above techniques is to present the data in a simplified form. This, in turn, allows an easier assimilation by the user of much of the information content of the data."

Jan 1, 1981

By J. Shahabpour

"Abstract - Breccias with angular and rounded clasts of a late-mineralization, ""barren"" hornblende porphyry dike set within a comminuted matrix consisting of rock fragments and quartz, cemented by quartz and K-feldspar of hydrothermal origin is observed in diamond drill cores from the Sar Cheshmeh porphyry copper deposit. Studies of age relationship between vein types, phyllic-altered clasts and the breccia groundmass suggest that the brecciation is a late event. The breccia clasts record evidence of hydrothermal reaction between the clasts and fluids responsible for the brecciation.Formation of bornite, in the breccia clasts of the originally barren hornblende porphyry dike, and in the breccia matrix, along with the scarcity of bornite in the Sar Cheshmeh deposit itself suggest involvement of fluids which are later and of different composition from the fluids responsible for the known mineralization at Sar Cheshmeh. These later fluids may be related to a later plutonic event and suggest the possibility of a later, and concealed deposit."

Jan 1, 1994

By Claude Hubert, Alex C. Brown, Pascal Marquis, D. M. Rigg

"Numerous studies of the Bousquet mining district, Abitibi, Quebec, mainly following the successive discoveries of new gold deposits over the past two decades, have led to a broad range of genetic hypotheses for their gold deposition. A compilation of petrographic, structural, and geochemical data indicates that the gold deposits are composed chiefly of pyritic schists derived from felsic and mafic volcanic and volcaniclastic protoliths, and of auriferous massive pyrite hosted by pyritic schists of felsic affinity. The deposits are typically located within zones of local pyrite enrichment and advanced-argillic alteration which are in turn enclosed within much larger zones of disseminated pyrite included in regional-scale, commonly anastomosing, zones of sericitic alteration.Overprinting relationships between three sets of folds and foliations indicate that the host-rocks of the gold deposits have retained the imprint of three successive generations of ductile deformation resulting from regional dynamothermal metamorphism. Sericitic and advanced-argillic alteration, together with massive sulphide deposition, are interpreted to have taken place prior to the onset of the ductile deformation, based on observations 1) of altered fragments of wallrocks which are enclosed within massive sulphide bodies and were thus preserved through regional metamorphism, 2) of the syntectonic deformed pyrite, and3) of the syn-tectonic porphyroblasts of andalusite, garnet and plagioclase. The orebodies are oblate to prolate, and the pyrite-gold mineralization is typically vein-type, distributed in foliation-oblique and foliation-parallel veins. The gold-bearing structures postdate all foliations, and are associated with retrograde alteration assemblages that are pseudomorphic after pea~-metamorphic porphyroblasts in host-rocks, and with cataclasticfabrics that overprint syn-metamorphic pressure-solution features and annealing fabrics in pyrite.Retrograde gold-bearing assemblages indicate a chemical disequilibrium between the ore-forming fluids and their host rocks. This disequilibrium rules out the possibility that gold was remobilized from its own host, and suggests, instead, that the ore-forming fluids and their metal contents had an allochtonous source. Stable and radiogenic isotope analyses indicate that the fluids had a metamorphic origin, and that the associated alteration took place after the culmination of the Kenoran orogeny."

Jan 1, 1990

By Janos de Warga

"After a short introduction to the history of the semi-conductor theory, the paper describes the principles of electron and hole flow in the semiconducting materials, the operation of the PN junction, and the rectification process in multi-layer devices (diodes and SCR's). The various methods of purification and zone-refining of the silicon are illustrated prior to the discussion on the most commonly used junction-forming processes (alloying, diffusing, etc.). Modern device fabrication and packaging operations are illustrated. Factory testing, evaluation, electrical parameters and guaranteed rating characteristics are listed. It is explained in this paper how the various device parameters affect the electrical performance of the finished unit and how the finished unit characteristics (turn-on, turn-off time, etc.) will influence the equipment rating. In concluding, some typical items of equipment are highlighted, and the applications of these semiconductor rectifiers in the chemical, mining, pulp and paper, and steel industries, etc., are dealt with."

Jan 1, 1967

By M. M. Helm

Samples sourced from the Goldstrike property in Nevada USA, have been evaluated in terms of their preg-robbing capacity and the physical structure of the graphitic carbon component in the carbonaceous gold ore. The study highlights a wide range in preg-robbing capacity between samples collected from the Betze-Post open pit and Rodeo underground mine. The physical structure of the graphitic carbon was assessed using Raman spectroscopy, and is found to play an important role in influencing preg-robbing behaviour. Differences observed in the physical structure of graphitic carbon are thought to be the result of hydrothermal events that occurred at Goldstrike.

Jan 1, 2011

By Shawn Harvey

HIGHLIGHTS of STAR DIAMOND PROJECT Initial underground bulk sample 4,048 ct / 25,253 tonnes: US$135/carat: 3,050 ct March 2005 $116 million financing: Newmont takes 9.9% SGF Prefeasibility study commenced on Star Merger with Kensington: 42.245% FALC-JV Voting agreement with Cameco in FALC-JV November 2005 $120 million financing: Newmont maintains 9.9% SGF Diamond valuation: 5,950 ct/ 36,529 tonnes: US$135/carat

May 1, 2006

By L. Voisin, K. Yamaguchi, D. G. Mendoza, K. Ltagaki

The behavior of arsenic and antimony in the Cu-0 system was thermodynamically investigated to understand their elimination during a blister-making stage in copper smelting. Firstly, the phase relations in a miscibility gap composed of the liquid slag and copper phases in the Cu-0-As and Cu-0-Sb systems at 1523 K were established by a quenching technique. It was found that arsenic and antimony distributed preferentially into the slag phase in the miscibility gap. Secondly, the activities of arsenic and antimony in the miscibility gap of these systems were determined at 1523 K by using a double Knudsen cell - mass spectrometer method. It was clarified that the activity of arsenic in the copper and slag phases showed the negative deviation from ideality while that of antimony in the copper phase a slightly positive deviation. These data obtained in this study suggest a possibility to eliminate arsenic and antimony by means of over-blowing in a converter after discharging the slag.

Jan 1, 2007

By S. Khoshkhooei

In this research, the effects of rare earth elements addition on thermal fatigue behaviors of AZ91 alloy were studied. Repeated heating and cooling cycles were applied on the samples at 170°C and 210 °C to develop thermal fatigue cracks, Crack growth mechanisms and microstructural influences were investigated by optical and scanning electron microscopy (SEM) as well as energy dispersive X-ray spectroscopy (EDS), Thermal fatigue behaviors were improved successively by addition of up to 2-wt% RE, This improvement is attributed to consummation of the aluminum of the melt by precipitation of the needle shape Al 11 RE3 phases, This process reduces the volume of Mg17Al12 phases and consequently decreases the brittle Mg/Mg17Al12 interfaces which are the main reason of weak thermal properties of the alloy at rather high temperatures, Further additions of RE, however, reduced the thermal shock resistance of samples by increasing in the mean length of the brittle needle shape phases.

Jan 1, 2005

By Barry D. Simmons

"A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck's approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-l990s and the company is confident that this target will be achieved.IntroductionAs one of Canada's oldest continuously operating mining companies, Teck Corporation traces its roots to Kirkland Lake, Ontario, with the development of the Teck-Hughes gold mine in 1913, later supplemented by production from the Lamaque gold mine in Val d'Or, Quebec. Control of the company was acquired by Temagami Mining Company, part of the Keevil Mining Group, in 1959. Credited as one of the first discoveries made using airborne geophysics, the Keevil Group had recently found the small but very high-grade copper deposits at Temagami, Ontario. These developments in eastern Canada formed a foundation for remarkable growth and Teck's present status as one of Canada's most successful and respected mining companies.Teck currently operates successful mining ventures across Canada and has international exposure through its association with Cominco Ltd., M.I.M. Holdings Limited and Metallgesellschaft AG. Operations in eastern Canada, however, remain an important component of Teck's ongoing success. The David Bell and Williams mines at Hernlo, Ontario, are Canada's lowest cost and largest gold operations, respectively. The Niobec Mine at Chicoutimi, Quebec, is North America's only significant producer of niobium. Teck maintains a 45070 interest in Golden Knight Resources Inc., part owner of the successful gold mining operation in the Casa Berardi area of northwestern Quebec. As a significant shareholder in Aur Resources Inc. and as a part owner, Teck is participating in the development of the Louvicourt deposit, a major base metal discovery at Val d'Or, Quebec."

Jan 1, 1992

By P. R. Brito-Parada, A. Norori-McCormac

Positron emission particle tracking (PEPT) has become an important tool for flotation research, as it is able to resolve directly the behaviour of particles in laboratory scale flotation vessels. The first applications of PEPT to flotation showed only the motion of an individual particle in the pulp and the froth, but nonetheless allowed interpretations of behaviour not previously possible. Since then, PEPT measurement and data analysis techniques have improved significantly and now ensure a high level of confidence in the particle behaviour obtained. In particular, statistical analysis of long-duration experiments allows time-averaged data to be collated, ensuring spatial accuracy and allowing rigorous comparison of different conditions. It will be shown that these PEPT techniques can be used to compare directly the effect of operating conditions and particle properties in a laboratory flotation system. Particle tracks will be illustrated, as well as analyses of particle speeds, average flow streamlines and occupancy that show marked differences in behaviour near the interface and impeller.

Jan 1, 2015

By J. Janeson

Wall control at the Pipe Open Pit is of primary importance in ensuring the long-term stability of the operation, while keeping costs to a minimum. Blasting techniques have been adapted to the variations in competence and structure of the wall rocks. A portion of the perimeter wall is being developed in incompetent peridotite . A recent change in pit slope design provides a wide safety berm on alternate benches. A support program which consists of pinning the crests of wide berms with vertical reinforced concrete dowels and horizontal bolting of walls shows evidence of increasing the stability of the pit walls. This paper describes the blasting and support techniques which are contributing to successful wall control in the Pipe operation.

Jan 1, 1979

By X. Cao, A. Birur, R. R. Chromik, J. Cuddy, P. Wanjara, J. Gholipour Baradari, T. Shariff

In this study, 3.1 mm thick Ti-5553 (Ti-5Al-5V-5Mo-3Cr) butt joints were autogenously welded using a 4 kW continuous wave Nd:YAG laser. The effect of welding speed and defocusing distance on the weld quality was investigated in terms of the surface morphology, welding defects, microstructure and hardness. Welds with full penetration were achieved at a defocusing distance ranging from -1 mm to 0 mm and welding speeds from 2.25 to 6.0 m/min. Underfill and porosity were the two main defects most frequently observed but within the optimum process window these defects could be maintained to meet aerospace specification tolerances. The fusion zone (FZ) consisted entirely of retained beta with a refined dendritic morphology. Compared to the bimodal alpha (a) + beta (ß) microstructure of the base metal (BM), the dissolution of the a phase was observed in the heat affected zone (HAZ), which led to an 11 % decrease in hardness from the BM to the FZ. To determine the tensile properties of the welded samples, an automated 3D deformation measurement system was used to measure the local strain in the weld region. The yield strength (YS) and ultimate tensile strength (UTS) increased with increasing welding speed with a highest joint efficiency of 75 % being achieved, albeit with a concomitant reduction in the ductility.

Jan 1, 2010

By D. J. McCulla

Mineral development and utilization affect the health of the economy and the pattern of long-term development throughout Canada. There are many diverse opinions on the contribution of minerals to the economy, but there is a dearth of adequate quantitative information. This paper discusses some recent research and provides some new information.

Jan 1, 1977

By Getu F. Biftu

There is general agreement among scientists that global surface temperatures have been increasing during the past decades. The increase in temperature is postulated to be the result of either an increase in greenhouse gases emission or climate variability (i.e., due to variations in sun or volcanic activity or El Nino and La Nina events) during past decades and may continue to increase. The effects of a predicted rise in the Earth?s surface temperature include an increase in average global evaporation and increase or decrease in precipitation (Bloomfield, 1992; Mann et al., 1991; Vinnikov et al., 1990; Gan 1995; Zhang et al., 2000a). The general circulation models (GCMs) project a global warming due to greenhouse effects of 1.5-4.5°C by the mid 2050s, with the most pronounced changes taking place in northern latitudes (Nicholls et al., 1996). However, similar predictions at a watershed scale or even a regional scale using GCMs are mot possible yet (Arnell et. al., 1996; Georgievskii et. al., 1996; Zhang et al., 2000a). Detection of historic trends, changes and variability in climatic variables is another indirect means of understanding potential future changes or variability at regional and local scales. The main objective of this paper is to review studies related to climatic change or variability and associated hydrologic changes at a regional scale and local scale, particularly those studies applicable to the Oil Sands Region (OSR) of Alberta. This paper identifies gaps in our current understanding of the hydrologic processes that may be affected by climate change; it discusses potential implications to developments in the OSR; and it explores mitigation opportunities including several that have already been implemented.

May 1, 2004

By Donald F. MacDonald

WE are living in a mineral and technological civilization. The Encyclopedia Britannica defines civilization as follows: "It is the final test of a progressive civilization that a given effort shall produce a larger modicum of average individual comfort, and the pursuit of this ideal has been from first to last the impelling force which drives civilization onward". This "individual comfort" demands labour-saving machines and devices such as motor cars, radios, and thousands of other inventions, most of which require minerals and metals in vast quantity for their manufacture. In fact, more minerals and fuels have been used in the last third of a century than in all previous world history. Since 1800, the world's production of metals has increased more than a hundred fold (1). Scientific discovery is now advancing on a wide front, thanks to the research work that is being carried on in progressive countries. The world's work is now being done with very much less human drudgery than in the past. We do not have to toil for our living as our ancestors did, even if we follow their occupations. The average man has had many years added to his life-span, but, apparently, little to his spiritual stature and less to his common sense.

Jan 1, 1939