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By D. King

Outline ? Regional Geology and Deposit types ? PM Deposit Exploration History and FNX?s Exploration Strategy ? Deposit Geology and Interpretation ? Resource Estimation ? Reconciliation ? Conclusions ? Breccia of comminuted footwall rocks from passage of shock wave due to meteorite impact ? Matrix ?pseudotachylite?-like? ? Variable re-crystallization of matrix due to thermal metamorphism &/or alteration

May 1, 2006

By Shahé Shnorhokian

Numerical modeling is increasingly being used as a tool to examine complex geomechanical issues related to rockmass behaviour and stability of underground openings. The in-situ stress regime and the evolution of mining-induced stresses during the life of an operation, taking into account the planned stope sequence, are topics that can only be handled through the use of a realistic and calibrated numerical model. This paper presents a case study of a deep underground Canadian mine in northern Ontario. A FLAC3D model was constructed and calibrated based on in-situ stress measurements. In the first stage, the evolution of stress regime was studied and compared with the occurrence of rockburst events during a period of three years. The locations of clusters were examined and compared to the mining sequence during that period. In the second stage, stresses within a diminishing ore pillar were examined based on the planned stope sequence and compared to levels deemed acceptable to the mine. Based on the results, an alternative sequence was arrived at to reduce stress accumulation in the pillar, or induce it to occur at a further distance from a brittle dyke in the vicinity of the orebody.

Aug 1, 2013

By S. J. Schofield

INTRODUCTION ONE of the greatest and most interesting problems of economic geology is to discover criteria bearing on the persistence of ore in depth. It is a question which is very much to the fore in connection with many of our important mines in British Columbia, and, as is to be expected, it is a most controversial one. The present paper, summarizing the views of the writers concerning the possibilities, in some of the mining districts of the Province, for the persistence of commercial ore to greater depths than have been, or are at present, mined, is offered as a basis for a general discussion on the subject and to call attention to the need for renewed study and research on the problem. Sooner or later-at some depth or other-individual ore-shoots become impoverished and bottom. In many mines where this has happened, either at the same or at a lower horizon, another ore-shoot, which had no surface outcrop, has been encountered and has continued downward until it, in turn, has pinched out. The Kolar (Mysore, India) gold field, for instance, presents interesting examples of this recurrence of ore-shoots at depth (1). For many years these mines have been under the management of Messrs. John Taylor and Sons. On more than one occasion they have persisted in sinking or drifting on barren quartz or along a narrow fracture for many hundreds of feet before values were again encountered. Their earliest experiment in such bold development took place at a depth comparable to that at which most mines in British Columbia are considered to be bottomed. In the past, is has been concluded that the ores in British Columbian mines do not go below approximately 2,000 feet, and to that depth only in a few instances. Consideration of the depth to which ores have been mined in the Province appears to support this view. The figures shown in the accompaning table have been gathered from various sources and are approximate.

Jan 1, 1935

By T. R. Heflin

The paper provides a comprehensive discussion of pump selection for the hydrometallurgical industry. Material suitability, in addition to proper size and design, will provide extended life for pumps in erosion /corrosion service.

Jan 1, 1979

By L. Dekker

"In 1979 Chevron Standard Limited and Irving Oil Limited intersected a thick, high-grade sylvinite zone in the Windsor Group in the Chevron Irving Malagawatch No. I well in central Cape Breton. This well was the third and final hole of a program designed to evaluate a non-commercial oil discovery made by Chevron Standard's Mineral Staff in 1978 while carrying out base metal exploration. Nine holes were subsequently drilled to evaluate the significance of the potash discovery. The delineation drilling proved the Malagawatch structure to be complex with the potash zone showing erratic grade and thickness distribution. Based on the drill information the potash accumulation at Malagawatch is uneconomic, however, other salt ""structures"" in the Bras d'Or Basin may in time prove to have better potential.History of DiscoveryIn 1972 Cuvier Mines discovered the Gays River lead-zinc deposit (MacEachern and Hannon, 1974) which prompted Chevron Standard's Minerals Staff to carry out a study of the Windsor basins in Nova Scotia (Figs. I and 2). As a result of this program several carbonate-hosted lead-zinc prospects were identified in the basal Windsor carbonate; one of these was at Malagawatch on Cape Breton Island . In 1978, after preliminary exploration surveys, a diamond drill program commenced consisting of 5 BQ holes (Fig. 3), three of which tested the basal carbonate. Instead of the reefoid bank facies of the Gays River Formation (Giles et al., 1979), the favoured host for economic base metal mineralization, this carbonate was developed as a laminated, pelletoidal, lime packstone more characteristic of the facies equivalent Macumber Formation (Schenk, 1967). While drilling one of these holes, No. 3-78, oil scum was intermittently detected on the drilling mud. The hole was abandoned at 191 m in anhydrite, without having reached the basal limestone."

Jan 1, 1985

By Jean-Yve Tremblay, Michel Prud'homme

"Industrial minerals include a group of more than fifty minerals which are marketed into almost all the sectors of industry; they are the backbone of many manufacturing industries. Table I shows major end-uses for industrial minerals in manufacturing sectors. At Energy, Mines and Resources, industrial minerals are divided in three major categories: (I) agro chemicals and chemicals, (2) construction mineral s, and (3) ceramics and specialty minerals. A listing of the major groups of minerals is shown in Table 2. Agro-chemicals and chemicals are sold on the basis of their chemical content and purity. Construction minerals or structural minerals are distinguished by their performance as low cost and bulky commodities. Ceramics and specialty minerals are performance-specific and are sold for their property on imparting functions on end-products. Industrial minerals have unique characteristics that are useful in many stages of processing; from crushed size to micronized fillers a single mineral ca n serve a broad range of industries because of its intrinsic properties."

Jan 1, 1988

By A. J. Neale, B. C. Flintoff

"A review of the dynamic rod mill-ball mill grinding circuit simulator developed at the University of Alberta, highlighting the modular structure and open-ended design, demonstrates the ease with which classical feedback control strategies can be designed and implemented. Various open loop simulations are presented to demonstrate the highly interactive nature of the grinding circuit and to indicate where potential control problems may be encountered. Closed loop simulations are examined, beginning with the basic SISO classical feedback control of circuit product size. Further improvement in the grinding circuit performance in the presence of various disturbances is realized through the application of a classical MIMO feedback controller. As an example of advanced (multivariable) control, static decoupling is implemented and shown to provide additional improvement in overall circuit performance.INTRODUCTIONIt has long been recognized in the processing industries that a dynamic process simulator is an indispensable tool in the design and evaluation of automatic control schemes. In mineral processing the lack of these simulators is felt to have been a major hindrance to the widespread implementation of effective process control systems. In particular dynamic simulation is a necessary precursor to any study of modern (as opposed to classical) process control methods. This paper discusses the development of a dynamic simulator that can be used to study various feedback control strategies. The simulation software provides a powerful educational tool for those individuals interested in grinding circuit control."

Jan 1, 1988

By J. H. Rickard, D. H. Watkinson

"Abstract - Detailed petrographic and quantitative (electron microprobe, SEM-EDS) mineralchemical analyses of sulfide ore from the 100 orebody at the Copper Cliff North mine, Copper Cliff, Ontario, reveal numerous stages of ore development. Sharp contacts between weakly mineralized quartz diorite and blebby to massive sulfides indicate multiple intrusive events within the Copper Cliff offset dike. A spatial association of sulfides and hydrous minerals, such as amphibole, biotite, chlorite and epidote, suggests that most primary ore has been affected by later hydrothermal fluids. Sulfides are often enclosed or bordered by these secondary silicate phases. The ore consists primarily of pyrrhotite, pentlandite, chalcopyrite, with trace michenerite, cobaltite/gersdorffite, irarsite, hessite, tsumoite, and bismuth tellurides.Geological and petrological comparison of the 100 orebody and the adjacent 900 and 890 orebodies has revealed distinct similarities in ore distribution. Data show that the 100 orebody is depleted in platinum-group elements (PGE) relative to the 900 orebody. Platinum-group elements from the 100 orebody may have been hydrothermally remobilized and partly emplaced in the 900 orebody, in adjacent veins, or in magmatic breccia. Analysis of Cu, Ni, and PGE assay data of ore samples has characterized their distribution among the eight different ore textures in the orebody. There is a strong association between Pt and interstitial sulfide, and to a lesser extent massive sulfide, but little correlation between chalcopyrite-rich ore and PGE in the 100 orebody, unlike many other deposits in the Sudbury region."

Jan 1, 2001

By Pierre Montrueil, Marcel St-Amant

Within the next few years, underground mobile equipment will be partially automated. Mining methods will integrate more and more automation. Such an evolution will be possible only if adequate underground communication systems are developed. This is expected due to the available competence in Canadian telecommunication, to the economic pressure on the Canadian mining industries for international competitiveness and to the social changes where a better working environment (i.e. less accidents) becomes a major concern. CCARM propose the concept of a Production Area Network for Automated Mobile Units called PANAMU as an intermediate size communication system. It can be implemented using mature present-day technology and it can be integrated in some mine wide communication systems. It can evolve so as to incorporate new technologies because of its modular concepts. In this paper, the communication requirements are estimated, the amtmptions are defined, the concepts of the PANAMU are presented and an over- view of its implementation is described. CCARM presents this article to the mining industry as a document for discussion.

Jan 1, 1994

By Chuck Crowell

ISO Standards ?Provide Information to Address Commercial and Safety Needs for Standardization: ?Definitions and Terminology ?Test Methods ?Performance Criteria ?Conformity Assessment Process ?Developed by Global Experts ?Promote Global Harmonization

May 1, 2013

By DAVID C. MILLER

Barite deposits occur worldwide and in a variety of geological environments. In recent years, several deposits of barite and barite-lead-zinc have been discovered in northern British Columbia, Yukon Territory and Alaska. Most are associated with Devonian-Mississippian age sediments, and many are syngenetic, bedded-type deposits. The Mel is a barite-lead-zinc deposit; it lies within Lower Cambrian strata and appears to be of epigenetic replacement origin. Figure I is an aerial view of the property from the south. Observations herein described are based largely upon field work, megascopic studies and two recent B.A.Sc. theses (Biasucci 1979, Rennie 1979).

Jan 1, 1984

By Mohammad. M. Khajeh

Rock mechanical properties are important parameters in geomechanical simulation. Considering stochastic heterogeneous models rather than conventional homogeneous layer cake models leads to more realistic simulation results and uncertainty assessment. These heterogeneous models are usually fine scale models generated by geostatistical techniques. Although considering high resolution property models is desirable, geomechanical simulation with a fine scale model is not computationally feasible for full?field, coupled geomechanical-flow simulation. Upscaling of property models is necessary to move from fine scale/high resolution property models to coarser scale/low resolution models appropriate for simulation. Local numerical upscaling was proposed by Khajeh et al. (2012) to describe the macroscopic elastic behavior of complex heterogeneous media and is expanded upon in this work. This numerical technique is not restricted to specific geologies as typical analytical techniques are. Moreover, transversely isotropic deformation is considered rather than the usual assumption of isotropic deformation. To compare the accuracy of the upscaling methodology, in this study shear strain is considered as the geomechanical response of a synthetic facies model and the response of the coarse scale model is compared to other conventional analytical averaging techniques. It is found that the numerical upscaling technique better approximates the geomechanical response of the fine scale model.

Jun 1, 2012

By James A. Deeks

"Motor failures and equipment bearing failures are responsible for reduced productivity.With the introduction of computers and data acquisition systems, users are now able to monitor, report and trend deteriorating conditions and take corrective action before a critical shutdown occurs.This paper discusses the monitoring and trend analysis of' motors, and motor and equipment bearings. With today's digital electronics technology users are now able to monitor their equipment, detect deteriorating or abnormal conditions quickly, alarm the condition locally and or remotely, and decide if immediate corrective action is necessary or if it can be delayed until the end of a work Shift. All of this can be done long before any damage is done to the equipment.Monitoring Trend AnalysisIt is no longer necessary to compromise in selecting products, since state-of-the-art designs allow the adjustment in such small increments that the users are able to detect minute changes in a system's performance.Monitoring and trending of motors and equipment bearings is now available in economical packages which can be expanded as a system grows. Simply select the information you need, set the parameters, choose the scan time, and decide on the degree of reporting.Buffer storage of short-term monitoring of a number of analogue channels permit the user to view the recent history of motor data such as: motor average load, unbalance, motor current, ground fault, reserve thermal capacity, plus all of the settings of the protective device.A decision can be made to freeze the stored information after the motor stops or after the motor starts. Then the user is able to recall the conditions and diagnose the performance and the cause of the abnormal condition. Typical scan times range from ¼ second to 5 seconds ."

Jan 1, 1992

By The Mill Staff

Professor H.E.T. Haultain: Table 4, on page 131 of this paper, gives the assays of sized mill products. I am sure that there are many others besides myself who would be very interested to learn how the sizes 0-3 and 3-13 microns were obtained. * * * Mr. Del Davis, Mill Superintendent, Flin Flon Concentrator, on behalf of the authors of the paper, has kindly sent us the following information in reply to Professor Haultain's enquiry. Sub-Sieve Sizing by Sedimentation Procedure (As used by R. J. Digney & J. E. Ryan, 1940) Fractionation of Sub-Sieve Sizes General Method: A 1,050-gram sample of the material was pulped to 3 liters; 10 c.c. of sodium silicate and 0.2 grams of Na2C03 was added and thorough agitation given for two hours previous to settling. The material was assumed to consist wholly of particles of the same density as the most abundant particles. The time required for a particle of the upper limit of the lowest size-range to be separated, to fall a specified distance was calculated according to Stokes Law. The pulp was poured into the settling apparatus and, when the calculated time had elapsed, the suspended material was drained. The settled sediments and the process repeated until no more suspended material was obtained. The next larger size fraction was obtained in a similar manner, using the settled sediments which had been stripped of all smaller sizes as above. The fractions were arbitrarily set at 0-3, 3-13, 13-23, 23-33, and 33-43 microns (43 microns = 325 mesh).

Jan 1, 1946

By M. P. Brameld, R. H. McCorkell

"Overburden covering bedrock uranium deposits was sampled to depths of 29 m and Rn concentrations measured at the same depths. Total-alpha activities, V concentrations and Rn emanation (J) of the samples were measured. The U-flux into the overburden was greater in the past: oxidation and dissolution has since removed most U, leaving decay products which indicate the presence of U deposits when U itself does not. Distributions of U and decay products and their ratios to each other reflect U-migration and degrees of U-removal. Rn distribution in overburden is related to the J of overburden samples and the presence and movement of groundwater. Simple, rapid methods of total-alpha and J measurement are described.IntroductionThe overburden drilling apparatus developed by Bondar-Clegg and Company makes possible sampling and radon measurement in overburden from the surface down to about 50 metres. This apparatus was used here to study the diffusion of uranium and its decay products from ore deposits into over lying overburden at the N deposit of the Amok Ltd. property (Cluff Lake, Saskatchewan) and on the Imperial Minerals Ltd. property at Gooderham, Ontario. These ores are enclosed in bedrock; the overburdens were deposited by glaciers or streams. The migration of uranium and its decay products in such situations and the factors which affect it have been little studied in the past, as readily usable techniques for mapping it in three dimensions have not been available. The results reported here are somewhat sketchy and preliminary, but they indicate the value of the methods used and some of the patterns to be expected. Surface and subsurface sampling and measurements were carried out on 3-line grids crossing known zones of mineralization. The lines were 60 metres apart at Gooderham and 40 metres apart at Cluff Lake."

Jan 1, 1982

By Stephen B. Hearn

The SLon Vertical Ring and Pulsating High Gradient Magnetic Separator was developed to overcome multiple disadvantages associated with traditional horizontal type Wet High Intensity Magnetic Separators (WHIMS) which have been in service for many decades for recovering iron ore and other minerals. Proven successful, with hundreds of units now upgrading low-grade iron ores and maximizing recovery of fines throughout China, the technology is now being tested in the Western world. This paper will discuss the drawbacks of traditional WHIMS, explain the operation of the SLon, and illustrate its practical use in processing hematite ores.

May 1, 2007

By Arthur Lieu

Outline Removal mechanisms of Se and Mo in the Key Lake Bulk Neutralization circuit Bulk circuit Detail process modification in the Key Lake BN circuit Process performance after commissioning Objective Legacy effects of Se and Mo from the historical operation of Key Lake mill were shown to have an negative effect on the regional biota in the downstream environment. The water treatment circuit was not designed to remove Se and Mo from the effluent. Reduce Se and Mo concentrations in final effluent under0.028 0.028 ppm ppm and 0.3 and ppm ppm(CNSC regulatory limits).(limits).??????

Nov 1, 2011

By Loris S. Pascoli

The increased pace of globalization in the mining industry has presented more opportunities for Canadian service companies to participate in ventures abroad. However, varying cultures, laws, competitive environments and contracting philosophies in other countries make it impossible to take for granted what is normal in the Canadian context. The author discusses some of his experiences and situations encountered in over 30 years in the diamond drilling industry, the last third of which were primarily focused on projects outside of this country.

May 1, 2001

By Jorgen Elbrond, Noel Billette

"La connaissance du niveau de variation de I' alimentation d' une usine minéralurgique est essentielle pour estimer le taux de récupération dans un concentrateur. De plus, il est important de connaître la période moyen ne de correlation afin d’améliorer la qualité des contrôles et de l' au tornatisation.Le modèle proposé permet de prédire ces paramètres à partir du minerai en place et des activités d'exploitation dans une opération à ciel ouvert. II est basé sur la combinaison des variogrammes directionnels dans diverses zones d'un gisement, ce qui permet de définir la correlation à la sortie de chaquc zone en fonction des decisions opérationnelles, puis sur une loi binômiale modifiée, afin de séparer minerai et stériles dans Ie but de décrire variance et corrélation dans Ie minerai même, Les statistiques classiques sont alors utilisées pour décrire la combinaison de plusieurs zones et obtenir la variance et la correlation au concentrateur.IntroductionUn concentrateur est habituellement rodé de facon à recevoir une alimentation à teneur fixe en métal ; Ie minerai qui s'y presente a, par contre, tendance à osciller auteur de cette valeur cible, tantôt plus riche , tantôt plus pauvre . Ces variations entraînent des pertes de deux types: tout d'abord, la teneur du concentré oscille de facon similaire à celle de l' alimentation , ce qui peut même impliquer des pénalties a I'usine de smeltage lorsqu'elle est trop riche ou trop pauvre; la récupération peut pour sa part être diminuée de plusieurs points par un engorgement du circuit lorsque la teneur est trop forte."

Jan 1, 1984

By Bennett McLaughlin, Gille Brousseau, John F. Cook

"La Mine Bousquet commenced operations in October 1979. Mining has been by underground methods from two main zones which dip steeply to the south , Sub-level stoping methods with following fill are used.The orebody and immediate country rocks are sericitic and highly schistose. The intensity of schistosity varies significantly and poor ground conditions prevail, especially within the orebody,Initially few mining problems were encountered but in May 1981, significant damage occurred. A system of stabilizing pillars was introduced with improved support systems. Predevelopment in ore and pre-drilling of blastholes were reduced with extra footwall development.Damage has continued to occur on a regular basis particularly during the spring thaw. Generally, the adverse conditions have been successfully overcome.IntroductionMost of the mining problems that have been experienced at Bousquet have been caused by poor ground conditions . This pa per describes these conditions, considers the cause and describes the ways in which the conditions have been dealt with . Despite the problems, Bousquet is a successful operation which in 1983 produced 95,000 ozs of gold from 514,000 tons of ore."

Jan 1, 1985