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By Forrest A. Kerr

Introduction During recent years the work of the Geological Survey in northwestern British Columbia has been in the nature of reconnaissance and exploratory mapping, largely for the purpose of gaining knowledge of the potential mineral-producing zones known to occur along the eastern side of the Coast range, and also to gather such data as might facilitate their exploitation. Commencing with fairly detailed mapping in the more accessible parts, the work has been continued and expanded until now an understanding has been gained of the more general features of a continuous section along the range for a distance of about two hundred miles. Geographically, northern British Columbia is more or less isolated. It is cut off from the central part of the Province by a rugged and mountainous country which, except for the telegraph line and a rarely travelled trail along it, is not penetrated by any developed routes or lines of communication. To the west, it is cut off from the Pacific by the Coast range, an extremely rugged area sixty to eighty miles in width which, except along the few navigable rivers cutting across it, cannot be readily traversed. Politically, it is further isolated in this direction by the narrow strip of south-eastern Alaska which borders the coast and extends inland to the axis of the range.

Jan 1, 1931

By W. A. Dixon Edwards

Gravel deposi ts in the Edmonton region are unique in their diversity in origin and age. The deposits were described first around the turn of the century (Dawson and McConnell 1896) . Among the many more recent in vestigations are works by Rutherford (1936), Shelley and Associates Limited ( 1977) and the City of Edmonton (1978) .

Jan 1, 1984

By V. Ogarlaci

Over 90% of the Romania's lignite reserve is located in the region of Oltenia, which is why this area is given special attention in the country's coal resources. Because the lignite deposit of Oltenia is comprised of 1-8 exploitable coal layers, their capitalizing calls for urgent arrangements to ensure rational exploitation under conditions of total safety, minimum losses and efficiency. The technology used the coal pits of North-Western Oltenia is the technology of excavation, transport and dumping in a continuous flow by using the complexes of excavation, transport and high-capacity dumping. The theme of this paper is of particular importance because the rhythmic operation in complete safety, is necessary both for sizing and keeping within the bounds of acceptable values, throughout the process of excavation of the geometric elements of the coal faces, marked by: the height of benches, slope angle and width of berms. Geometric dimensions of the benches of the open pits, the height of benches, slope angle and width of berms shall be calculated and shall be based on: the massif structure that forms the benches; physical-mechanical characteristics of rocks from the bench; working conditions, characterized mainly by mining and extraction methods applied; functional parameters of the mechanical equipment used to perform various operations on the coal face etc. For this study it was necessary a broad field for task tracking, measurement, research and design elements of the coal face, for land survey and a desk activity by: processing of topographic data, laboratory analyses on physical and mechanical properties of rocks and numerous specialized studies. In the final part, we bring some contributions to elucidating the issues of special importance for the lignite coal pits of Oltenia, coming up with data, graphics, formulas, solutions and concrete dimensioning of coal faces in terms of using technology in a continuous flow.

Aug 1, 2013

By Rob Kelso

The PISCES Goals ? To conduct research and develop programs to enable and promote planetary surface exploration ? To host international tests and technology demonstrations at the PISCES Test Site. ? To promote STEM education, inspiring students by connecting Hawaiian culture to space exploration and settlement. - economic and workforce development ? To involve the commercial sector, spinning off technologies to help the local Hawaiian economy. ? To develop a full-scale, technically valid, analog lunar/Martian outpost on Hawai`i Island.

May 1, 2013

By J. Janzen

The cost to supply ventilation may exceed 40% of the total mine energy cost for underground mines and is often higher for deeper mines. The goal of Ventilation-on-Demand (VOD) is to ensure that the required quantity and quality of air is supplied to underground mining crews and diesel equipment at the least energy expenditure (minimum cost). A VOD system may include control of surface fans (Supply & Exhaust), underground booster fans, auxiliary fans and automated regulators/dampers to regulate the flow of air with more control elements providing more value. Strategically located Air monitoring stations measure air quantity and quality and provide feed-back enabling control. The modular design involving controls, intelligent instrument and intelligent motor control centres coupled with a communication network allows the quick installation, commissioning and expansion of the system as the mine develops. The result is a very robust, flexible system while reducing maintenance costs and spare parts. This paper discusses the impact of sensors, installation and commissioning on advanced controls and provides solutions for in-field applications.

Aug 1, 2013

By Evans B. Mayo

ABSTRACT Orange Footwall 'sill' is locally concordant locally discordant, with the structure of its sedimentary walls. The sediments were folded in two directions. Folds, following both these directions, are preserved in the concordant portion of the 'sill'. It seems, therefore, that the porphyry has replaced the sediments, thus preserving within itself their structure. During replacement, the nascent porphyry may have been much weaker than its walls. Accordingly, under directed pressure, the porphyry could have flowed locally, disarranging the replaced structures within it and developing a flow structure discordant with the folds in the sediments. Some such action may account for the discordant parts of the 'sill'. INTRODUCTION The senior author has seen certain granitoid massifs that have an internal structure vastly different from, and discordant with, the structures in their wall rocks. It seems that? such massifs have moved independently of their surroundings. Yet, a structure section elsewhere in the same mountain range may reveal granitic rocks with internal structures that appear to continue the structure of the invaded rocks. In such a case, it is at least thinkable that the granite has replaced the older sediments or volcanic rocks. In February, 1950, the writers mapped, on 15 level of the Nickel Plate mine, near Hedley, B.C., a diorite or gabbro porphyry 'sill' that, in one cross-cut (1503), appeared to be quite concordant with the wall-rock structures, whereas in another cross-cut ( 1500) about 100 feet to the south, the same porphyry was discordant (see Figure 1).

Jan 1, 1951

By L. O. Cooper

IN THE operation of most mines, hoisting ropes, made of steel, play a very important part in the conveying of men and material between surface and the underground workings. It is obvious that, in order to maintain a maximum degree of safety, certain restrictions must be placed on the loads that may be carried by hoisting ropes, as well as on other factors that may affect the life of the rope. It is the purpose of this paper to suggest ?a new method of defining the necessary restrictions. The three main stresses in a hoisting rope are the static stress, bending stress, and dynamic stress. Crushing stresses, which are also present, are largely indeterminate and may best be allowed for by proper grooving of drum and sheaves, by adequate inspection of cross-over points, and by limiting the number of layers on the drum. They will, therefore, not be considered in this analysis. In the ?recent Ontario regulations, the limiting conditions for the main stresses are specified separately. The static stress is limited by setting a minimum static safety factor of 5.0 The dynamic stresses are allowed for by specifying a minimum capacity factor of 8.5, which has the effect of increasing the safety factor required at smaller depths in a uniform manner. The bending stresses are limited by calling for a drum-dia./rope-dia. ratio of at least 60 for ropes up to 1 inch in diameter and 80 for ropes greater than 1 inch in diameter. One disadvantage of this method is that the controls are too rigid and do not allow the operator sufficient freedom of action within safe limits.

Jan 1, 1951

By P. J. Adams

Environmental regulations require means for controlling emissions of SO2 NOx and particulate when burning coal. The combustion of coal in limestone fluidized beds is one of the most promising techniques for the necessary reduction in emissions. Fluidized-bed firing, furthermore, offers potential economies in capital equipment. The world's largest steam generator applying fluidized-bed techniques was built under the sponsorship of ERDA and installed in Rivesville, West Virginia. This paper describes the design and discusses the start-up and development difficulties which were experienced during the period from initial operation to current readiness for commercial operation. Other developments leading to utility and industrial fluidized-bed steam generating equipment are reviewed. The future potential of this promising technique is discussed.

Jan 1, 1979

By George J. Thompson

This pa per deals with the internal characteristics of steel and its response under cold northern temperatures. General maintenance procedures and specific repair techniques are covered.

Jan 1, 1973

By D. W. McDonald, N. A. Duke, R. L. Hauser

"The NERCO Con Mine is situated in the amphibolite facies aureole of the Western Plutonic Complex overprinting the Yellowknife Greenstone Belt. Metamorphic grade of the upright monoclinal basaltic succession decreases from hornblende-amphibolite facies along the border of the batholith to greenschist facies. Metamorphic isograds, subparalleling the faulted margin of the batholith, transect volcanic stratigraphy and coincide with major goldbearing shears.Gold mineralization is confined to north-striking, west-dipping shear zones where hangingwall amphibolite facies mineral assemblages retrogress to chlorite-carbonate-sericite-sulfide bearing schists hosting multiple generations of quartz-ankerite veins. The gold-producing portions of the Con and Campbell Shears occur where these structures transect an east trending thermal corridor. The corridor is defined by granitic plugs and a number of related breccia bodies, that can be traced outwards from the batholith across the greenstone belt.Prograde reactions of greenstone during amphibolitization effectively liberate fluids that partition metals. With retrograde reactions at shear zones, gold is precipitated with quartz due to the destabilization of sulfide and arsenic complexes. The coupling of regional prograde metamorphic and restricted retrograde metasomatic overprints suggest mineralization is temporally related to emplacement of the Western Plutonic Complex. Economic gold concentrations within the intrusive corridor indicates enhanced metamorphic overprint of hornfelsed greenstones enveloping satellite intrusives peripheral to the main batholith."

Jan 1, 1993

By Magdy Ibrahim

Detailed as-built project schedules are necessary to close out construction projects, benchmarking, forecasting, dispute resolution, and improving cost estimates of future projects. Manual procedures for developments of as-built documentation is time consuming, involves numerous interfaces and human interventions. This paper presents computational framework that encompasses automated site data acquisition and generates schedule updates utilizing commercially available project scheduling software. The work is carried out collaboratively with a Hydro Quebec team. The site data is captured employing mobile computing using iPad® type computers and Wi-Fi. The information is directly compiled in a centralized database server. The synchronization tool is a bi-directional application and is used on servers to communicate with iPad® computers deployed onsite. The captured data is stored in Microsoft SQL® relation database that consists of 63 entities. Computer software application has been developed in Microsoft Visual Basic® (vb.net) environment for extracting the collected site data, linking the database to the as planned schedule, and generating the actual, also known as as-built schedule. The development can be utilized in automated progress reporting, evaluating future bids, generating master schedules and a wide range of efficient EVM applications.

Aug 1, 2013

By M. Tanaka, H. Narita, T. Fuchikami, K. Morisaku, K. Nagao, T. Yoshida, K. Kuroda

The effect of various N-substituents on the performance of amide-containing tertiary amine compounds in the extraction of Rh(III) from HCl solutions was investigated to optimize the structure of these compounds for industrial use. It was found that N-2-ethylhexyl-bis(N-di-2-ethylhexyl-ethylamide)amine and tris(N-di-2-ethylhexyl-ethylamide)amine, which have long, branched alkyl chains, were suitable for Rh extraction, because they were soluble in a practical diluent (80 vol% n-dodecane?20 vol% 2-ethylhexanol) and stable against highly concentrated HCl/Rh solutions, and showed high selectivity for Rh(III) over Pd(II) and Pt(IV).

Jan 1, 2014

By Thomas Hauquin, Olivier Deck, Yann Gunzburger

"In this study, 2D numerical modeling of a room-and-pillar mine is conducted along with the calculation of all terms of the mechanical energy balance. Simulations of different geometrical and geomechanical configurations are performed in order to investigate the conditions that favor a high seismic energy release (instability) during the excavation (removal) of one single pillar. At first, classical stressstrain simulations enable us to estimate the elastic and quasi-static response of the mine. Then, owing to the implementation of new functions in the modeling code, the seismic energy released when the pillar is removed is calculated. The obtained values are found to be in agreement with those calculated analytically using a modified energy balance based on the works by Cook (1967) and Salamon (1984).It is shown that the mine’s proneness to release large amounts of seismic energy, after sudden removal of one single pillar, mainly depends on three parameters: the initial extraction ratio of the mine, the depth of the exploited seam and the Young’s modulus of the surrounding rock mass compared to that of the ore. Moreover, it is pointed out that the magnitude of the seismic energy can be greater than that of the stored elastic energy, meaning that the dynamic (seismic) transient stresses should not be neglected when compared to the quasi-static stresses, particularly when trying to prevent the risk of rockburst and collapse in underground mines."

Jan 1, 2015

By Jan Drzymala, Przemyslaw B. Kowalczuk

"Flotation is possible when the forces operating between a bubble and the attached particle are properly balanced. There are many forces operating in the bubble-particle aggregate. The magnitude, location and direction of the forces depend on the type of process. The simplest arrangement in flotation is when a spherical bubble is attached to a spherical particle and both are immersed in water. In such a system there are four essential forces which shape the stability of the bubble-particle aggregate. They are excess pressure and interfacial solid/liquid, solid/gas and liquid/gas forces. A proper analysis and balance of the size, location and direction of these four principal forces lead to a general equation delineating the stability of the spherical particle–attached bubble system. Specific cross sections of the system and solution of the general equation lead to different relationships including the Young formula as well as the well-known geometrical relation between contact angle, particle and bubble radiuses. The arrangement of forces in the proposed graphical representation of the Young law is different from that presently used in literature for a bubble attached to an unmovable solid particle. Many real solid/liquid/gas systems are more complex due to the presence of additional forces which change the regular curvature of the liquid/gas interface leading to advancing and receding contact angles.INTRODUCTIONThere are numerous papers (Athukorallage, Aulisa, Iyer & Zhang, 2015; Chau, Bruckard, Koh & Nguyen, 2009; Drzymala, 1994; Lubarda, 2012; Pellicer, Manzanares & Mafe, 1995; Wang, Cui, Zhou, Xu, Sun, & Zhu, 2014; Young, 1804) and books (Davies & Rideal, 1963; Defay & Prigogine, 1966; Lee, 2013; Lyklema, 2000) dealing with the solid/liquid/gas system. Many of them concern the three involved phases having the shape of a sphere or spherical cap and the formed contact angle. The contact angle is usually measured through the liquid phase and can be either smaller or greater than 90o. The essential part of these publications is a graphical representation of the system with the Young equation shown as a result of balance of only three forces that is the excess Gibbs (or Helmholz) free energy per unit area of the three involved interfaces (Davies & Rideal, 1963; Defay & Prigogine, 1966; Israelachvili, 1985) (Figs. 1a-c). The Young equation, when the gravity force/buoyancy is neglected, is:"

Jan 1, 2016

By J. Currie, J. McManus, R. Chenier

"Cominco Copper Division's Valley Mine is located in the Highland Valley of British Columbia, approximately 275 km by air northeast of Vancouver. The nearest towns are Logan Lake, located IS km to the east and Ashcroft, located about 50 km to the northwest.Preproduction stripping of rock and overburden at the Valley Mine's Lake Zone Pit began in mid-1982 following a decision to discontinue mining in the adjacent Jersey Pit. Equipment and mining methods were carried over from the Bethlehem Copper operations which, with Valley Copper Mines, were merged into Cominco in December 1982.Blasting practices, as carried over from the Bethlehem pits, were designed to provide the fine fragmentation required to meet production requirements using the Bethlehem crusher. However, after mining the first few benches of the Lake Zone Pit, it became apparent that overblasting at the pit limits was causing a number of bench failures, as well as contributing to an over-all reduction of the material strength of the rock mass forming the southwest wall of the pit.With present ultimate pit plans calling for the southwest wall to be as high as 300 m, Valley staff realized that potential slope stability problems should be dealt with as early as possible. This philosophy would enable experimentation on phase pit walls in order to attain the optimum slope angle on the ultimate pit wall.As part of an over-a ll slope stability program, a controlled blasting program was initiated at the Lake Zone Pit in March 1983. In this program, Valley engineering and production staff worked together with Golder Associates in establishing design criteria and evaluating the results. This program resulted in a marked improvement in the soundness of pit walls while maintaining the required degree of fragmentation."

Jan 1, 1985

By M. P. Rennick, D. M. Burton

Abstract -The Murray Brook massive sulfide deposit, which was the first geochemical discovery in the Bathurst camp, is one of the largest sulfide deposits in the area. The massive sulfides are hosted by quartzose metasedimentary rocks in the lower part of the Ordovician Tetagouche Group. This thick succession of sedimentary rocks is overlain conformably by felsic volcanic rocks, and is structurally overlain by mafic volcanic rocks. The massive-sulfide body is polydeformed, but primary metal zoning is still discernable and may permit future exploitation of discrete lead-zinc and copper zones. Although it was discovered in 1956, the deposit was not developed unti11989, when Murray Brook Resources commenced processing of gossan containing precious metals. Recovery of gold, silver, and mercury is accomplished by indoor vat leaching on a year-round basis.

Jan 1, 1992

By S. J. van Rensburg

Competition for resources, including water and arable land, refocused attention on water and gold tailings management with respect to quantity and quality. MINTEK established and validated an "Advanced Leach Facility" to record kinetic leach information aimed at gold refractory sulphide ores. This facility was developed because of the need for additional leach process information to enable proactive decision making. Instead of focussing on optimised gold recovery only, the impacts of pre-oxidation methodologies were evaluated by considering key parameters, including cyanide speciation, reagent consumption, thiocyanate, arsenic, heavy metals, salt loads, water quality and residue stability. Results from oxidative leaching of a refractory gold ore employing oxygen, ozone, ultra-fine grinding, high shear and pressure oxidation are discussed. The relative cyanide and lime costs and environmental and sustainability effects associated with these technologies are briefly outlined.

Jan 1, 2011

By Juliana Parreira

The past decade shows record increases in global demand for minerals and metals with an accompanying significant decline in skilled personnel. Mining companies today are examining new technologies to maximize production, reduce costs, and create safer work conditions to deal with this shortfall. Automation of an open-pit mine haulage system is receiving attention as a beneficial option since it provides more consistent and efficient operation of mining equipment, it removes workers from potential danger, it reduces fuel consumption significantly reducing greenhouse gas (GHG) emissions, and it can help optimize vehicle repairs and equipment replacement because of more-predictable and better-controlled maintenance. This paper describes a simulation model under development using the EXTENDSIM software package to examine scale-up issues and constraints of autonomous vehicles in comparison to a manual system. The software can predict and manage Key Performance Indicators (KPIs), such as productivity, safety, cost, equipment failures, fuel consumption, and tire wear under different road and load conditions. By breaking-down the various systems of an autonomous haulage truck and simulating the overall haulage system using a Monte Carlo approach, the model becomes a flexible and powerful tool to use within a mining organization. Direct comparison to a manuallyrun system can be done to show the cost and operational benefits of automation. Project managers can use this tool to guide decision-making about possible application of autonomous haulage trucks at a specific mine site.

May 1, 2010

By Felix D. Klebe

Efficient, high volume, mine load out operations have evolved in recent years to include more sophisticated control systems that integrate with mission critical equipment such as weighing systems. Traditional weighing systems often involve static weighment of individual railcars and either manual or serial transmission of scale data to a database application. In recent years integration of railcar or truck weight data into a loadout operation via direct PLC or Ethernet communication between the weighing terminal and the loadout control system has been realized. Furthermore, use of dynamic railcar weighing where railcars are automatically weighed while moving has increased productivity in a variety of mining applications.

May 1, 2008

By A. Fawceit, B. C. Dyer

"The basis of the tomographic velocity imaging technique is briefly described and an application of the method to detect and image a cross-section through a chromite pod is presented. Using the chromite application as an example, the relative costs of tomographic data acquisition and processing are compared with those of diamond drilling to obtain similar resolution. A number of different tomographic survey configurations and the potential role of the method in surface and underground exploration are discussed.IntroductionThe technique of seismic tomography has been most widely applied in oil industry exploration, nuclear waste disposal, civil engineering site investigations and in the assessment of the condition of mass concrete structures. Although model studies had indicated that tomography would be a useful tool in mineral exploration, relatively few applications have been reported.Essentially the method relies on the determination of the speed with which sound travels through a region within a cross-section of the earth or large body. The speed of sound is determined by the physical characteristics of the medium through which it is passing. In geophysics the speed of sound is generally referred to as the seismic velocity. Due to variations in the formations of different rocks the seismic velocity will vary and so can be used to map geological boundaries"

Jan 1, 1994