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By R. E. Whitehead, G. J. Prior

"Abstract -Biotite from aplite that appears to have crystallized simultaneously with disseminated Cu-Mo mineralization at MacLeod Lake in northern Quebec yields K-Ar dates in the range 2032 ± 44 Ma to '2f1:)1 ± 47 Ma. The mean value, 2065 Ma, is some 400 Ma younger than the 2485 ± 64 Ma date obtained from a hornblende concentrate separated from a granodiorite sill that is spatially, but apparently not genetically, associated with the disseminated Cu-Mo deposit. The mean biotite date of 2065 Ma at MacLeod Lake, a K-Ar date of 2055 Ma reported from an area 50 km east of MacLeod Lake and published dates of about 2000 Ma for galenas from the Chibougamau Cu-Au ores, suggest a widespread thermal and mineralization event, in that part of the Superior Province east of James Bay, that differs from the common late Archean mineralization that is related to volcanism and metamorphic-intrusive activity.Sommaire - Les datations au K-Ar sur des biotites qui auraient cristallisé en même temps que la minéralisation disséminée en Cu et Mo dans une aplite mise en place au Lac MacLeod, au nord du Québec, s'échalonnent entre 2032 ± 44 Ma et '2f1:)1 ± 47 Ma. La datation moyenne, soit 2065 Ma, est d'environ 400 Ma plus récente que la datation obtenue pour un concentré de hornblende extrait d'un fùon-couche de granodiorite qui est spatialement mais ne serait pas génétiquement as­ sociée à la minéralisation disséminée en Cu et Mo. La datation moyenne de la minéralisation au Lac MacLeod, soit 2065 Ma, la dataion au K-Ar à 2055 Ma citée pour une région à 50 km à l'est du Lac MacLeod, de même que les datations d'environ 2000 Ma établies pour des galènes qui se trouvent dans le minerai aurifère et cuprifère à Chibougamau, suggèrent un phénomène thermique répandu qui aurait produit la minéralisation dans cette région à l'est de la Baie James, dans la province du lac Supérieur. Ce phénomene serait différent de celui qui aurait produit la minéralisation répan­ due d'âge archéen tardif qui elle serait associée à l'activité volcanique et à l'activité intrusive accompagnée de métamorphisme."

Jan 1, 1992

By Ali Montaser

Hauling trucks are important part of equipment fleets for large earthmoving operations such as those encountered in dams and highway construction projects. This paper presents an automated methodology for tracking and estimating productivity of hauling trucks fleet operations in near-real-time. Recent advancement in automated site data acquisition technologies made their use in tracking and monitoring of construction operations feasible. However, these technologies fail to track hauling truck fleets due to the change in the cut and fill locations from one cycle to another; making tracking and progress reporting difficult and inaccurate. In addition, there is very little work done utilizing data sensed directly from equipment, for example sensing when truck dumping bed is raised during the dumping process. The technologies deployed in the developed method are Radio Frequency Identification (RFID) and equipment control sensors. Low cost passive RFID tags are attached to hauling trucks and fixed RFID readers are attached to loaders or excavators. The read range of the used RFID tag is centimeters, to be activated only when a loader with an attached RFID reader is loading a truck. On the other hand, control sensor is connected to the truck control system and operated by the motion of its movable bed. The function of control sensors is to record the signal time when the truck operator gives order to the truck control system to raise or lower truck bed. The captured data is then transferred wirelessly from the RFID reader and control sensor to a computer housed in one of the temporary offices onsite and subsequently to the main server in the contractor?s head office. Fusing the data captured from RFID reader and control sensor is used to identify loading, travel, dumping and return time that constitute the hauling truck cycle time. The collected data is analyzed and processed automatically, without human intervention, to calculate the productivity of the hauling truck and to report it directly to onsite personnel. Relational database is developed to support the implementation of the proposed method. The developed database is used to process the data captured by the RFID and the control sensor to calculate the productivity achieved in cutfill operations in near-real-time. The developed methodology is expected to facilitate early detection of discrepancies between actual and planned performances.

Aug 1, 2013

By Gordon L. Kidd

The object of this paper is to show the relations of the East Coulee coal area to the near-by Willow Creek, Wayne, Rosedale, and Drumheller areas, all being parts of the Drumheller field. The word ?area? is here used in a more local sense than that employed by Dr. J. A. Allan, whose. 'area' is rather comparable with the 'mining division' in British Columbia. I have drawn freely from the published information, particularly from Dr. Allan's report on the "Geology of Drumheller Coat Field, Alberta", and from Dr. E. Stansfield's paper on " A Chemical Survey of Alberta Coals", to whom thanks are due. The Drumheller field is served by branch lines of the two principal Canadian railways. The C.N.R. traverses the district by its Goose Lake line from Calgary to Saskatoon; and the C.P.R. by a line from Calgary to Acme and then southeasterly to Drumheller, where it effects a junction with the C.N.R., over which the C.P.R. has running rights as far as Rosedale. From Rosedale, a joint line built during the summer of 1928 extends about forty miles down the Red Deer river to the mouth of Bull Pond creek. From that point the C.P .R. turns more southerly to connect with the Bassano-Empress line. The C.N.R., it is expected, will eventually proceed eastward to connect with a transcontinental line. The joint line from Rosedale down the Red Deer river opened up the Willow Creek and East Coulee areas.

Jan 1, 1929

By Pierre Laliberté

L?utilisation de plusieurs nouvelles technologies et systèmes de contrôle visant des économies d?énergie dans une exploitation minière pourrait laisser croire qu?il suffit d?additionner les économies potentielles de chacune de ces technologies pour en évaluer l?économie totale. Une addition simpliste des pourcentages d?économie pourrait, dans certains cas, dépasser 100%, ce qui est évidemment totalement incohérent. Les LMSM-CANMET sont à réaliser une étude dont les résultats serviront à estimer l?influence de certaines technologies et systèmes de contrôle visant des économies d?énergie et à évaluer l?impact des unes sur les autres. En outre, un modèle de simulation est en cours de création afin d?évaluer les gains incrémentaux liés à l?application d?une série d?innovations dans une exploitation minière. La présentation fera le point sur l'état d'avancement du projet en plus de soumettre quelques exemples.

May 1, 2007

By K. A. Clark

A meeting between representatives of the Scientific and Industrial Research Council of Alberta and the Deputy Minister of Mines for Canada was held at Edmonton in May, 1929, for the purpose of formulating a co-operative plan for carrying forward studies in aid of the development of commercial methods for utilizing the bituminous sands of Alberta. It was agreed that to the Alberta Research Council should be allocated the general problem of investigation of the processes for the separating of bitumen from the sands, including studies of methods of emulsifying, dehydrating and otherwise preparing separated bitumen for industrial applications. It was further agreed that during the present year the work of the Alberta Research Council should be to continue its laboratory investigations of points of design of its separation plant; to further perfect its separation procedure; to recondition its existing separation plant at Dunvegan Yards, Edmonton, in the light of laboratory studies and to operate it for the purpose of demonstrating its efficiency; to carry on tests in emulsifying and dehydrating or otherwise preparing separated bitumen for industrial application; and on the basis of the experience gained in the operation of the preliminary plant at Dunvegan Yards to prepare and design and, as far as possible, to proceed with the erection of, a semi-commercial separation plant at a site to be chosen, probably at the bituminous sand deposits near McMurray, Alberta. This paper presents, in the main, a progress report of the carrying out of this programme.

Jan 1, 1929

By S. K. Dimitrov

?Ellatzite Med? is one of the biggest mining companies in Bulgaria, processing about 12,000,000 t of ore per year. Waste materials left after extraction of copper concentrate are deposited in tailings dam ?Benkovski 2?. The hydraulic structure is built according to the downstream method, through hydrocyclonization where the downstream batter and the body of the wall are formed by the separated coarse sand particles of the separated tailings. In connection with the prolonged concession of Ellatzite Med and the enlarged capacity of Benkovski 2, the tailings dam has expanded on to the surrounding terrain. To guarantee a normal hydrocyclonization and build up of a tailings wall during waste deposition from the ore mill, the technological scheme of the hydraulic transport system of Benkovski 2 has been changed.

Aug 1, 2013

By R. Blazej

Machinery Systems Division (MSD) in the Institute of Mining Engineering at Wroclaw University of Technology specializes in belt conveying systems analyzing, calculating and design. Within the division operates the certified Laboratory of Belt Transportation (LTT) and Laboratory of Rollers. Since few years, a group of several people have begun work on developing a comprehensive system for the automatic evaluation of condition of conveyor belts working in the mines. Group uses both magnetic devices developed by specialized companies servicing belts and its own machine vision system developed for assessment of belts covers and edges during belt movement (up to 7 m / s) on the specially designed for this purpose the test conveyor. Recently they have got the research grant funded by the National Centre for Research and Development (NCBiR) for development of the system for automatic diagnosing of conveyor belts? condition and aiding of rational belt management. On the basis of previously created diagnostic tool called ABCDE (Automatic Belt Condition Diagnostic Equipment) the five modules: vision-A magnetic-B, preventive-C, forecasting?D, and determining safety factor-E will be developed. They will automatically interpret data about conveyor belts? condition to indicate the extent and timing of repairs, to prevent failures and to select the optimum moments for their replacements. The system will use results of ongoing research & development and planned research concerning modeling of belt wear using evolutionary genetic algorithms. The reached stage of research can not yet allow to start the implementation work by potential users. It is therefore necessary to pursuit research in real scale, the development of new modules (C-E) and intensive testing of the system in working condition with system calibration to optimize the economic effects.

Aug 1, 2013

By J. Desroches, J. Burghardt, B. Lecampion, A. P. Bunger

"We present detailed comparisons between theoretical predictions and experiments for the initiation of radial hydraulic fractures transverse to a wellbore. Most of these experiments provide a measure of the time evolution of pressure, length, opening and flux entering the fracture during the test. We compare all these measurements simultaneously to our theoretical predictions, thoroughly testing hydraulic fracture initiation theory, which is shown to be predictive. These comparisons notably emphasize the difference between the initiation pressure (the wellbore pressure for which the fracture initiates) and the breakdown pressure (a misnomer which simply corresponds to the maximum pressure recorded during the test). INTRODUCTION In this paper, we will compare hydraulic fracturing laboratory experiments performed in different tight materials (PMMA, cement, shale) with the predictions from a numerical solution of the governing equations of hydraulic fracture mechanics (e.g. Geerstma & de Klerk, 1969; Detournay & Peirce, 2014). We focus on transverse radial hydraulic fractures initiating from a radial notch at the wellbore wall (see Figure 1). In particular, we will clarify the difference between the initiation pressure (the wellbore pressure at which the fracture initiates) and the breakdown pressure (a misnomer which simply corresponds to the maximum pressure recorded during a test, usually carried out at constant pump rate). This difference stems from the strong viscous effects at play during wellbore pressurization, fracture initiation and early propagation (i.e. fluid entrance in the newly created fracture). It has been observed on a number of experiments (e.g. Weijers, 1995; Zhao et al., 1996) and has a strong practical application, first because the maximum pressure is the most obvious value to report and second because that maximum value is necessary to specify injection systems."

Jan 1, 2015

By R. Howard

"In projects involving resource development and plant optimization, the use of in-mine geophysics can deliver considerable benefit. The value proposition lies in using very high resolution downhole measurements to model process-plant outcomes. The calibration procedure used to convert in-situ physical properties into process engineering parameters is illustrated using two iron ore projects. Data correction was related either to orebody structure or mineral formation. The deliverable from this approach is a series of high-definition sections indicating the variability of ore delivered to a front-end separation plant and parameters for mine scheduling and stockpile design needed for maximum product yield.RÉSUMÉ Dans des projets de développement des ressources et d’optimisation de l’usine, l’utilisation de la géophysique minière peut engendrer des bénéfices considérables. La valeur de la proposition réside dans l’utilisation de diagraphies à très haute résolution afin de modéliser les résultats de l’usine de traitement. La procédure d’étalonnage utilisée pour convertir les propriétés physiques in situ en des paramètres d’ingénierie de procédés est illustrée en se basant sur deux projets de minerai de fer. La correction des données porte sur la structure de la masse minérale ou de la formation minérale. Les livrable attendus de cette approche sont une série de sections à haute définition, signalant la variabilité du minerai livré à une usine de séparation de première ligne, des paramètres pour l’échéancier de la mine et la conception des haldes requis pour une production optimale."

Jan 1, 2016

By D. Cronin, A. Plumtree, A. Hosseini

"Crack in corrosion (CIC) linepipe defects are hybrid defects not directly addressed by existing assessment methods. To investigate the collapse pressure of these defects, CIC defects were formed in 508 mm (20 in) diameter, 5.7 mm thick API X52 linepipe. These defects were 200mm long and varied in depth from 3.0 to 3.8 mm. The respective failure pressures decreased from 14.3 MPa for the plain pipe to 7.9 and 6.2 MPa respectively. A standard FAD method was applied to evaluate these defects as equivalent length and depth cracks, predicting the rupture pressure conservatively by 18% on average. However, when assessed as equivalent cracks with a reduced wall thickness corresponding to the corrosion depth, the predicted collapse pressures were more accurate, approximately 14% conservative on average.INTRODUCTIONPipelines are a safe and efficient method for transporting high volumes of oil and gas. However, aging pipelines may experience defects, such as cracks or corrosion. Present approaches include detection, assessment and repair of defects before they may become critical to the integrity of the line. There are different codes and standards for assessing pipeline defects, depending on the type of defect, with API 579 (API, 2000) being the most common code for the assessment of cracks in oil and gas pipelines . Corrosion is commonly assessed using RSTRENG (Kiefner & Vieth, 1989). Other methods such as the Finite Element method and the CPS method (Cronin & Pick, 2002) may be used for crack and corrosion, respectively.At present, there is no specific method or procedure for assessing crack in corrosion (CIC) defects, and as a consequence there is a need to provide an assessment and evaluation of the integrity of these defects in order to determine the requirements for defect repair or hydro line testing. Hence, the goal of this study was to provide guidance for the assessment of CIC defects for linepipe.CRACK IN CORROSION DEFECTS (CIC)Significant amounts of corrosion and cracking are not generally found together (Hosseini, 2010). However, a new hybrid defect including cracking within corrosion (CIC) has been identified in operating pipelines. In this case, cracking coincident with corrosion (schematic shown in Figure 1) provides the motivation for the current study."

Jan 1, 2012

By T. Yeomans

NVI Mining’s Myra Falls operation is a forty-year-old underground mining operation feeding a 4,000 metric tonnes per day concentrator. The current mill, built in 1985, was designed to process a massive sulphide ore-body. This orebody, known as the HW, contains about 50% pyrite. Minerals of value are chalcopyrite and sphalerite, with precious metals occurring in all mineral types. By 1997, mining of a new ore-body, known as Battle-Gap, commenced. Mineralogically complex, the new orebody contains about 15% pyrite copper minerals, including primary chalcopyrite and secondary bornite, chalcocite and tennantite, combined with increased galena and sphalerite. Flotation performance generally decreased with increasing amounts of Battle-Gap ore types, with both copper concentrate quality (increased lead and zinc content) and copper recoveries being affected. Following significant metallurgical test-work, a new, fully sequential copper-lead-zinc flotation flow sheet and reagent scheme was developed. This sequential flow sheet was progressively installed and commissioned during 2006. Copper concentrate lead and zinc smelter penalty contents have been reduced by some 40%, while increasing copper recovery by 10%.

Jan 1, 2009

By T. ?kre, O. M. Dotterud, S. Haarberg, J. Thonstad, G. M. Haarberg

An electrowinning pilot plant has been constructed at Falconbridge Nikkelverk A/S, Kristiansand, Norway. The equipment consists of a mixing tank where the electrolyte composition and temperature are controlled, an electrowinning tank equipped with five cathodes and six anodes of commercial size and design and a dechlorination facility. Electrowinning experiments were carried out in this pilot plant using acid cobalt chloride solution from the cobalt tankhouse. Key parameters were varied to obtain an improved understanding of the cobalt electrowinning process, focusing on the detrimental deposition of cobalt oxide on dimensionally stable anodes. The extent of anode scaling was found to be dependent on the electrowinning conditions. Low pH, temperature and cobalt concentration resulted in less scale being formed, however at the expense of cobalt current efficiency and cell voltage, adversely affecting electrowinning production capacity and energy consumption. When operating at high acidity, pH in the anolyte was higher than in the catholyte, which is believed to be due to H+ ions taking part in the current transport across the diaphragm, migrating out of the bags surrounding each anode.

Jan 1, 2005

By Mehmet Guney

This article is based on a detailed heat investigation conducted at the Rokana Division of Nchanga Consolidated Copper Mines Limited while both authors were employed in Zambia. Mindola Mine is one of the three underground mines comprising the Rokana Division on the Copperbelt of Zambia, producing about 270,000 tons of ore per month at 1.9% Cu and 0.14% Co. The total volume of air being circulated by means of five primary fan installations slightly exceeds 1,000 m3/sec at standard density. Sectional bulk cooling is practised where air cooling coils are installed at primary splits some considerable distance from the stoping operations. Total capacity of the refrigeration complex is 10,500 kw (3,500 R. tons), of which about 7,000 kw is available as effective cooling power after losses, but the heat removed from the coifs is about 3,500 kw with 61% over-all plant performance. An extension program is planned for a further five production levels with the re-deepening of a sub-vertical shaft. Thermal heat will become a major problem at increased depth associated with higher rock temperature, higher thermal conductivity of the rock groups encountered and fissure water flowing into working areas through the strata with increased rock temperature. This paper describes the ventilation and refrigeration practices in Mindola Mine, with special reference to future thermal heat problems. These are discussed with a view to mining at depth.

Jan 1, 1979

By R. I. Iacobescu, Y. W. Chiang, A. Van Audenaerde, R. M. Santos, T. Van Gerven, P. Knops

In this work, we explore a novel mineral processing approach using carbon dioxide to promote mineral alterations that lead to improved extractability of nickel from olivine ((Mg,Fe)2SiO4). The precept is that by altering the morphology and the mineralogy of the ore via mineral carbonation, the comminution requirements and the acid consumption during hydrometallurgical processing can be reduced. Furthermore, carbonation pre-treatment can lead to mineral liberation and concentration of metals in physically separable phases. In a first processing step, olivine is fully carbonated at high CO2 partial pressures (35 bar) and optimal temperature (200 °C) with the addition of pH buffering agents. This leads to a powdery product containing high carbonate content. The main products of the carbonation reaction include amorphous colloidal silica, chromium-rich metallic particles, and iron-substituted magnesite ((Mg1- x,Fex)CO3). Carbonated olivine was subsequently leached using an array of inorganic and organic acids to test their leaching efficiency. Compared to leaching from untreated olivine, the percentage of nickel extracted from carbonated olivine by acid leaching was significantly increased. It is anticipated that the mineral carbonation pre-treatment approach may also be applicable to other ultrabasic and lateritic ores.

Jan 1, 2014

By B. McHenry, A. E. Wraith, P. J. Mackey

The Wallaroo smelter on the Yorke Peninsula, South Australia commenced smelting operations in 1861 treating ores from the nearby Moonta and Kadina mines. The plant expanded and modernized on several occasions and was a leader in the successful introduction of new technology to improve operations. It operated continuously until 1923 when local mines became exhausted; in the closing stages of the 19th century it was the largest copper smelter in the world outside of those in Swansea, Wales. In 1892 a small electrolytic refinery was established at Wallaroo, the first in Australia, based on principles developed by Elkington at Pembrey, Wales in 1869. The Wallaroo refinery was specifically built to recover gold and silver from copper produced by smelting gold-containing feed materials shipped from Western Australia. This first venture into electrolytic refining was replaced in 1903 by a somewhat larger refinery which, although modest in size for its time, with a capacity of about 1000 tonnes of cathode copper per year, was very productive in precious metals. Anode copper was produced by an updated version of the reverberatory-based Welsh process until 1910 when barrel-type pneumatic converters were introduced based on American practice; subsequently, anodes were cast by tapping the precious-metals rich "bottoms" portion of converter copper as produced at about one-fifth into the copper blow. The present paper describes the Wallaroo refinery, its anode supply and products, supported by initial observations on a sample of a Wallaroo cathode held in the collection of the South Australia Museum, Adelaide SA, Australia. INTRODUCTION Australia ranked 6th in the world for copper mine production in 2018, with an output of 918,000 tonnes of mined copper, after Chile, Peru, Congo, China and the USA; about 40% of Australian mined copper was smelted in the country. Interestingly, the world ranking of Australia in mined copper has, with a few variations, remained about the same for more than 100 years – of interest, it was also the 6th largest country for copper production at 21,089 tonnes in 1899. At that time, all or most of the copper was smelted in the country (Mackey, 2016). Copper was first discovered in Australia in 1842 in South Australia not far from Adelaide; additional copper discoveries in the region soon followed. At first, copper ore was shipped to Swansea, Wales for smelting (Bampton, 2003). However, in addition to the long, 150 day one-way sea passage, it seems Welsh smelters preferred higher grade of ores – these aspects and likely a mood in the new colony to be independent of Swansea (Evans, 2014) evidently encouraged local smelting at the mine sites using small, Welsh-type reverberatory furnaces fired with hardwood as fuel and operated by Welsh and Cornish migrants. The first large copper smelter in Australia commenced in 1848 at Bremer, near Callington some 60 km east of Adelaide. With larger discoveries on Yorke Peninsula, the Wallaroo copper smelter at Wallaroo Bay on the west coast of the peninsula commenced operations in 1861 (Bell & McCarthy, 2008). Thus began one of the most successful, and in its day, one of the most advanced and innovative plants in Australia if not the world. In the late 1860s, it was considered one of the largest copper smelters in the world (Bell & McCarthy, 2008)

Jan 1, 2019

By A. W. Jolliffe

AEROPROSPECTING may be defined as the application of the air view to the search for mineral deposits. The term is suggested as a preferable alternative to either aerial prospecting (which may be confused with areal prospecting) or air prospecting. The air view may be obtained by visual observation from an aircraft or by examination of air photographs; each has its particular advantages and disadvantages. Aeroprospecting should be regarded only as an aid to, and not as a substitute for, accepted prospecting methods ( l ). The Precambrian region north of Great Slave lake consists of two well defined physiographic units, a feature first noted by J. T. Wilson (2). The boundary between these lies close to the north shore of the east arm of the lake and extends northwesterly near Spencer, Beniah, Carp, and Ghost lakes (Figure 1). South and west of this line, exposed bed-rock makes up the greater part of the land area; eskers are very rare, and overburden is largely limited to rock-walled valleys and depressions. North and east of the line, outcrops are rare or absent, eskers are abundant, and most of the surface consists of drumlin-like drift hills, elongated parallel to the direction of ice movement (Figure 2). Where this boundary passes through the area shown in Figure 1, it lies near the 1,200-foot contour and may mark the maximum extent of the lake or sea arm present in this vicinity toward the end of the Pleistocene period. For convenience, the first area may be called the 'bed-rock belt' and the other the 'drift belt'.

Jan 1, 1945

By Kostas Fytas

Acid mine drainage (AMD) is a serious environmental problem that preoccupies the Canadian Mining Industry. Considerable amounts of money are spent every year in an effort to prevent or reduce the acid mine drainage phenomenon. AMD occurs when sulphide minerals (ex. pyrite) contained in rock are exposed to air and water and subsequently oxidize to produce low pH water. This acid effluent has the potential to mobilize any heavy metals contained in the rock. Coating the sulphide minerals with silicates is a new promising technology to reduce AMD. Pyrite is treated with a solution containing H2O2, sodium silicate and a buffering agent. H2O2 oxidizes a small part of pyrite producing ferric iron (Fe3+) ions. These ions subsequently react with the silicate ions to produce ferric hydroxide-silica that precipitates on the pyrite surface producing a passive coating. This silicate coating can protect the grains of pyrite from oxidation. This paper presents a series of experiments that confirm that silicate coating can considerably reduce AMD.

May 1, 2001

By J. Seo

We propose a dynamic biomechanical simulation method that uses motion capture to evaluate the risk of Work-related Musculoskeletal Disorders (WMSDs). Statistics show that WMSDs accounted for 33% of all non-fatal occupational injuries and illness in construction in 2009, and were a leading cause of temporary and permanent disability. Present methods rely largely on self-reports from workers, observational techniques, and direct measurements of motion and muscle activity to assess awkward postures, physical loads, repetitiveness, and the duration of exposure. While these methods have helped to prevent WMSDs in construction work, they may not be suitable for estimating the internal tissue loads associated with WMSDs. We propose a dynamic biomechanical simulation method to estimate internal forces and moments at each body joint of construction workers with motion capture data. Particularly, we explore the biomechanical loads by simulating active 3D musculoskeletal models based on measured postures and movements. To demonstrate the feasibility of this approach, we studied a ladder climbing task using a portable ladder under controlled laboratory conditions. Postures and motions were determined with a commercial motion capture system (e.g., VICON). The results were analyzed to investigate the feasibility of identifying risk factors based on biomechanical simulation. The results show that the proposed approach allows us to determine the biomechanical basis for WMSDs, and to identify postures and movements associated with excessive physical demands on each body joint. When combined with marker-less motion capture which is our ongoing work, the proposed approach has the potential to assess an individual?s motions and to provide personalized feedback for the purpose of reducing biomechanical loads and WMSD risk in real workplaces.

Aug 1, 2013

By W. E. Roscoe

The probability of making an exploration discovery in Canada can be calculated from Derry's (1970) data on exploration expenditures and number of discoveries over the last nineteen years. Considering an average exploration "try" to be $30,000, the probability of a discovery with one try has decreased tenfold from about 0.01 in 1951 to 0.001 in 1969. A plot of these probabilities can be extrapolated to the future, giving a 1969-71 three-year average probability of 0.00096 with 90 per cent confidence limits of 0.00042 and 0.00153. Using this probability, various calculations can be made, such as (1) the probability of making at least one discovery for any given exploration expenditure, (2) the probability of ultimate ruin or survival of the exploration investment process and (3) the expected value of an exploration investment. There is a critical minimum amount per discovery that must be re-invested in exploration, no matter how large the original investment is, for exploration to survive at all in the long run. Currently, this critical minimum is $31,200,000 with 90 per cent confidence limits of $19,600,000 and $71,400,000.

Jan 1, 1971

By A. M. Bell

"Hallnor mine is in the township of Whitney, Porcupine district. To date, its production of gold has been second largest in the east Porcupine field. Ore was discovered in the property in 1936 by diamond drilling in overburdened country. This drilling was undertaken by Noranda Mines following the discovery of ore in conglomerate at Pamour 1 mile to the east.Milling commenced at the Hallnor in June 1938, and to the end of 1945 432,000 oz. gold had been produced from 889,000 tons of ore, giving an average recovery of 0.49 oz. a ton.The West mine of Pamour, the Broulan orebody, and the veins on the Hallnor and Bonetal are all parts of a mile long vein system that has been separated into three sections by cross faulting. In consequence, they could well have been described in one paper. In treating them individually the viewpoint obtained from each may lead to conflicting opinions, and any conclusions advanced in this paper on the general structure should be modified by the conclusions advanced in papers on the neighbouring properties.GENERAL GEOLOGYRock FormationsThe Hallnor orebodies occur within 400 feet of the contact between lavas and sediments, and may lie in either lavas or sediments. The lavas near the ore consist of flows of pillowed andesite and one flow of more acid and less sheared and chloritized lava locally named trachyte. These flows strike east-west and dip steeply. At the surface on the east side of the property the volcanics have been intensely altered to a massive carbonate rock having a north-south thickness in excess of 1,000 feet . This carbonate body extends west across the property with a plunge of 45° (Fig. 1)."

Jan 1, 1954