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By J. R. Andrews, R. P. Young, J. M. Reyes-Montes

"Microseismic monitoring provides insight into the location and extent of rock-mass fracturing induced by cave mining, enabling interpretation of the cave profile and validation of predictive numerical models. Source location uncertainties can lead to misinterpretation of the inferred characteristics of the fracture network. One principal source of uncertainty is the velocity model used to invert the location algorithm. Large-scale 3D numerical models of modulus changes across a caved mass can represent such complexities in the location algorithms, allowing more accurate interpretation of the microseismic activity. A Northparkes mine case study applies this advanced approach to microseismic data interpretation.RÉSUMÉ Le suivi microsismique fournit des renseignements sur la localisation et l’étendue des fractures de la masse rocheuse induites par l’exploitation par blocs foudroyés; cela permet d’interpréter le profil de la chambre foudroyée et de valider les modèles prédictifs numériques. Les incertitudes quant à la localisation de la source peuvent conduire à des mésinterprétations des caractéristiques inférés du réseau de fractures. Une des principales sources d’incertitudes est le modèle de vitesse utilisé pour inverser l’algorithme de localisation. Des modèles numériques tridimensionnels à grande échelle des changements du module d’élasticité à travers une masse foudroyée peuvent représenter de telles complexités dans les algorithmes de localisation, permettant ainsi une interprétation plus juste de l’activité microsismique. Une étude de cas à la mine Northparkes applique cette approche avancée à l’interprétation des données de microsismicité."

Jan 1, 2016

By Y. Zedan

In this study, the statistical design of experiments (DOE) was applied to study and regulate the properties of near-eutectic Al-11%Si alloys. Develop regression equations for such response variables as hardness, yield stress, ultimate tensile stress, percent elongation, total cutting force, cutting power, and tool life together with other factors which, include the percentage composition of the alloying elements, and the requisite modification (Sr) level. These equations may be analyzed quantitatively to acquire an understating of the effects which the main variables and their interactions may have on the mechanical behaviour and the machinability of the alloy under investigation. The results reveal that increasing the levels of Cu and Fe content results in an increase in hardness, yield stress, and ultimate tensile strength in both modified and non-modified alloys. On the other hand, both Cu and Fe appear to affect the percentage elongation adversely, whereas the Sr-level has a positive effect on this parameter. It was found that Sr-levels have the most significant effect on the cutting forces and cutting power followed by the content in Fe and Cu. The results also reveal that the interaction coefficients of these variables have a significant effect on tool life compared to the main independent variables. This fact may be attributed to the formation of complex insoluble phases between Cu, Fe, Si, and Al as investigated using Scanning Electron Microscopy (SEM) attached to an EDX analysis system. The accuracy of the regression equations in predicting the expected properties has been verified by carrying out random experiments in the range of variation of these variables.

Jan 1, 2011

By Pedram Sahba

In today?s emerging economy, pooling resources is a growing trend to reduce overall system costs. Two important resources of every maintenance department are repair shops and spare parts. In this work, we consider a system consisting of mine drills at multiple areas in a mine. In each area, a number of identical drills are operational. When a failure occurs, the defective component should be repaired in a designated repair shop. The failed component can be replaced immediately if a spare part is available. Otherwise, the drill is down until a component is repaired and put back into service. In this paper, the effect of pooling resources is examined, and the conditions under which it is beneficial to pool the resources are investigated. In addition, determining the optimal number of stand-by units, equipment or spare parts, in each case is of interest.

May 1, 2013

By Real Daigneault, François Robert, J. Paul Golightly, Jean-Yves Cloutier, Jayanta Guha, Pierre Pilote

"The Casa-Berardi East, Center and West deposits, located in the Archean Abitibi, Sub province, are hosted by volcanic and sedimentary units of varying compositions, less than300 m from the Casa-Berardi fault (CBF). The CBF, a brittle structure, represents an increment in the structural evolution of a regional-scale deformation zone showing ductile-brittle behavior known as the Casa-Berardi deformation zone (CBDZ). The CBDZ is characterized by a mylonitic Sc1 foliation which is folded a.n4 deformed by a later sczfoliation in high strain zones.Four generations of quartz vein and fracture systems have been recognized within the Casa-Berardi deposits. Most economic gold mineralization, occurring in the second generation system, is found within high strain zones. This system hosts three types of mineralized structures: (1) banded quartz veins; (2) swarms of veins and mineralized host rocks; and (3) disseminated sulphides along fractures. An early carbonate hydrothermal alteration zone (pre- to syntectonic) surrounds the deposits. Alteration associated with gold mineralization is contemporaneous to late ( syn- to post-tectonic) relative to the development of progressive deformation in the CBDZ. The geological characteristics and paragenesis of the four quartz vein and fracture systems developed as an integral part of the geodynamic evolution of the Casa-Berardi deformation zone."

Jan 1, 1990

By D. Gorc, T. M. Fraser, Z. T. Nikic, R. Pesalj

"Mount Polley is an alkalic porphyry copper-gold deposit of Lower Jurassic age within the Quesnel terrane in south-central British Columbia. The silica-saturated Mount Polley intmsive complex is assumed to be coeval with volcanic rocks of similar composition in the Nicola Group in which it was emplaced. Other intmsions and some of the volcanic rocks in the Mount Polley area are silicaundersaturated and contain feldspathoids.The Mount Polley deposit is characterized by multiple intrusions that vary from diorite to crowded plagioclase porphyry to monzonite. Intmsion breccias are associated with some of the intmsive phases. Abundant hydrothermal breccias occur on the margins and above plagioclase porphyry intmsions. These breccias provide the main host for mineralization and are associated with the highest concentrations of copper and gold. The breccias are subdivided into four distinct types based on the dominant hydrothermal mineral in the matrix. Actinolite breccia is developed in an elongate zone within the core of the Central zone and grades laterally and vertically into biotite breccia to the southeast. Magnetite breccia is irregularly distributed and is relatively sparse throughout the deposit and albite breccia is dominant in the West zone. Pervasive and vein-related alteration correlates with the breccia types. The core of the hydrothermal system at Mount Polley is subdivided into three zones: actinolite, biotite and K-feldspar-albite. The margins of the core zone are overprinted by a discontinuous zone of calc-silicate minerals. This intermediate zone passes outward into propylitic alteration. Mineralization is most prominent within hydrothermal breccias and is generally present as disseminations, blebs within the matrix and abundant veins. Mineralization is associated with a chalcopyrite-magnetite-bornite assemblage in the core of the deposit passing out into magnetite-pyrite-chalcopyrite. Relatively constant copper to gold ratios suggest that both metals were precipitated under similar conditions.Hydrothermal breccias are genetically related to the emplacement of the crowded plagioclase porphyry melt. Crystallization of the melt was probably accompanied by volatile/aqueous exsolution, forming a water saturated carapace. Decompression of the chamber in response to magma withdrawal, fracture propagation and possible fault movement allowed hydrothermal brecciation to occur at the apex and margins of the intmsion. Alteration and mineralization appears to have been controlled by fluids migrating away from the plagioclase porphyry."

Jan 1, 1995

By K. Fagerlund, L. Rosenback, T. Mäkinen, Y. Anjala

This paper deals with the nickel smelter and refinery concepts Outokumpu has applied at Harjavalta and several other plants. Also other process routes and modifications developed and tested by Outokumpu during the recent years are highlighted. Outokumpu started nickel production in Harjavalta in 1959. Until 1995 the Flash Smelting - Peirce-Smith (PS) converting route was applied. High grade nickel matte from the converting step was further refined by means of leaching and electrowinning to produce cathode nickel. In 1995 the nickel production capacity was increased from 17 000 t/a to 52 000 t/a based on the Direct Outokumpu Nickel Smelting Process (DON). In the DON process PS converting is eliminated and high grade nickel matte with low Fe-content is directly produced in the flash smelting furnace (FSF). Metal values from the smelting slag are recovered in the electric furnace (EF) as iron containing Ni-matte. The DON process can be operated with either two matte concept, where high grade FSF matte and EF matte are produced, or a single matte concept, where EF matte is recycled to the smelting furnace and thus only one type of high grade matte is obtained. The additional refinery capacity at Harjavalta is based on hydrogen reduction producing.

Jan 1, 2005

By D. R. Derry

"IT WOULD TAKE a braver man than I to try to forecast the future of mining exploration far into Canada's second century. Even to look ahead ten or twenty-five years we must review the figures of the fairly recent past -and I have found this quite a time-consuming but interesting job -in order to find trends and project them into future years. The trends to which I will refer are: firstly, the annual expenditure on exploration and its relation to value of output; secondly, the discovery rate and its relation to production initiations; and thirdly, the methods by which discoveries have been, and will be, made. Exploration Expenditures Figures on the annual expenditure on mining exploration in Canada have been collected and published for some years by the Do-minion Bureau of Statistics. These have some unavoidable limitations; e.g., in the varying definition between one company and another of what comprises ""Exploration"" and in the difficulty of getting complete returns. However, although the actual figure for a given year may be subject to question, I believe that the relative figures from one year to another are reasonably reliable. There is also a lapse of time between the collection of data and publication -the last published figures are for the year 1963. In bringing the figures up to date to 1966 I have canvassed eight of the larger mining and exploration companies and obtained their figures for 1963 to 1966 inclusive, and then averaged these for each year and applied the progression to the 1963 figures."

Jan 1, 1968

By A. K. Croteau

"At Craigmont Mines Limited, Merritt, B.C., the mining practice of trackless sub-level caving was started in the latter part of 1966. This type of mining was new to the mine personnel and the mining industry of Canada as a whole. Sub-level caving has presented many old and a number of new problems in maintaining the equipment used in this method. This paper will deal with some of these problems as they affect this particular mining operation. It will be impossible to review all phases of the equipment, but an attempt will be made to cover the most pertinent aspects in maintaining the drilling, mucking and hauling, and auxiliary equipment."

Jan 1, 1970

TRE ? worldwide leader in InSAR ? Spinoff of Polytechnic University of Milan ? Numerous patents for cutting edge technology (e.g. SqueeSAR?, PSInSAR?) ? Focus solely on InSAR with over 13 years experience ? ISO 9001 quality certification ? Powerful scalable parallel processor to handle all jobs What can InSAR provide for mining? An advanced suite of tools for monitoring ground deformation over mine sites: ? Deformation maps ? A dense network of measurement points ? Time series ? Cross sections of surface profile evolution

Aug 1, 2013

By P. H. Agson Gani, T. Sitorus, N. P. Widodo

"PT ANTAM UBPE Pongkor underground mine use blasting to develop its tunnels which will cause poisonous and dangerous gases trapped inside mine. To analyze this case, a study of mine ventilation, the dispersion of carbon monoxide (CO) gas concentration and diffusion coefficient is commenced. At the end, the re-entry time formula will be determined. Results indicate that this study is site specific and could only be applied in the place this study executed. The aim of this study is to be further developed by applying Principal Component Analysis (PCA) to find a universal re-entry formula. KEYWORDS Mine Ventilation, Re-Entry, Smoke Clearing, Diffusion Coefficient, Carbon Monoxide Gas, Gas Dispersion INTRODUCTION Pongkor underground mine is using cut and fill as its mining method. Thus, its development and production processes require blasting to develop its tunnel. This process caused poisonous and dangerous gases spread and trapped inside the mine, one of them is carbon monoxide (CO) gas. CO is formed in an unbalanced reaction of explosives detonation and could be the cause of headache, blackout and death to people who inhale CO at certain concentration (McPherson, 2011; Hartman, Mutmansky, Ramani, & Wang, 2012). Mine ventilation system is installed in the mine to resolve this problem. Mine ventilation play an important role to disperse CO gas by absorb the poisonous/dangerous gases and deliver clean air into mine. The important parameter is diffusion coefficient, because diffusion is affecting particulates or gasses spreading from its sources throughout the mine. Diffusion coefficient is the total diffusion in axial direction of turbulent flow mainly by convection of bulk motion, advection and eddy diffusion, while the effect of molecular diffusion is appreciably negligible (Widiatmojo et al, 2015). Taylor (1953, 1954) develops a theory about the dispersion by inducing a slow stream of solvent into a capillary tube. Taylor used Reynolds assumption of radial diffusivity to be analogous with the transfer of the matter in turbulent flow as well as the transfer of momentum and heat. Then, Taylor proposed the formula of diffusion coefficient, D (m2/s), against pipe diameter and turbulent shear velocity are as follow:"

Jan 1, 2019

By A. Roy MacLean

"Cape Breton is an island on the eastern extremity of Nova Scotia, Canada. Here, coal mining under the Atlantic Ocean has been a way of life since the early French militia mined coal for heating purposes in 1720. Despite many ups and downs over the intervening years, the coal industry has survived and is now in a favourable position to benefit from the upswing in international coal usage.Mining in Cape Breton Early mining in Cape Breton was done by hand picks and shovels. The coal was loaded into mine cars which were hauled by horses to the main haulage system for transport to surface. Later, compressed-air cutting machines and drills led to the use of explosives to blast the coal so that it could be loaded by hand and transported as above. In 1923, longwall mining (by hand) was introduced. In 1950, the Dominion Coal Company developed the Dosco continuous miner in order to mechanize the longwall coal-getting operation. At this time, conveyor belts came into wide-spread use, along with diesel locomotives to haul mine cars from the longwall face to the main transport system. During this period, coal was also mined by conventional mechanized room-and-pillar equipment such as cutting machines, loaders, roof bolters, etc. This system evolved into the use of the continuous ·miners of today, which are employed in the Lingan Mine room-and-pillar section. However, this method is only satisfactory at shallow depths and gradients. For these reasons, almost all the coal in this coal field will be mined by longwall methods. In 1968, the Government of Canada expropriated the assets of the Dominion Coal Company on Cape Breton Island in order to prevent complete closure of an uneconomic industry by its owners. The government created, by an Act of Parliament, the Cape Breton Development Corporation which now operates the coal mines, coal preparation plants, railway, shipping pier and ancillary services (Fig. 2). Since its inception, the Corporation has closed three mines, opened two new mines, is in the process of developing a third new mine, and has invested heavily in the one mine which remains from its previous owners."

Jan 1, 1985

By W. L. Sherwood

Present conventional techniques for primary steelmaking in both integrated and non-integrated plants are outlined. 'Direct reduction' alternatives are reviewed and categorized according to the nature of the product produced, with particular emphasis on the limited number designed to yield steel as the end product. A proposed new technique, referred to as the Sherwood Process, is described in some detail as a new combination of selected features from the prior technology. This process is in-tended to realize, in integrated operations, the result of continuons steelmaking directly from the ore in a single plant and, in non-integrated operations, continuons steel-making from a metallic charge of scrap, sponge iron or pig iron. Prominent features are continuons processing in elongated, horizontal, rotary furnace equipment, controlled direct heating of each process stage and, for the over-all integrated process, a size separation for removal of excess solid reductant and other waste just prior to the melting step. Material and energy balances are presented as well as exemplary cost data. Reasons for selecting this particular combination of process elements are dis-cussed.

Jan 1, 1968

By C. M. Kleemann

The paper describes the present milling practice at Western Mining Corporation Limited's new nickel mine at Kambalda in Western Australia. It details the crushing, autogenous grinding, flotation and spray drying circuits for the production of a nickel concentrate. It also indicates some of the metallurgical problems which have been encountered in concentrating this ore.

Jan 1, 1973

By F. P. Morawski, J. E. Schelske, J. R. Geddes, B. R. Eberts, D. M. Wilson, J. D. Jeffries

"The Griffith Mine is located 200 miles northeast of Winnipeg and is 30 miles south of Red Lake, Ontario. Owned by The Steel Company of Canada Limited and managed by Pickands Mather & Co., it has an annual rated capacity of 1.5 million tons of high-grade iron ore pellets with an analysis of 66.3 per cent iron and 4.5 per cent silica.Development of the mine and construction of the plant got underway in January of 1966 and operations began in February of 1968. The orebodies outcrop on the shore of Bruce lake and run under the lake. The ore in its crude form is a metasedimentary low-grade magnetite and occurs in a highly folded banded formation. The average iron analysis of the crude is 29 per cent and the over-all weight recovery is 32 per cent.In order to mine the portion of the orebody under the lake, the soft varved clay on the lake bottom was hydraulically dredged and a dyke constructed of rock, with till used to provide an impervious seal on the lake side of the dyke, prior to dewatering.Mining is carried out by conventional open-pit tech-niques. Ore dressing is achieved by combining one crushing stage and a two-stage grinding system, with beneficiation by magnetic separation, hydroseparation and flotation. Agglomerating is done with conventional balling drums and pelletizing is carried out in shaft furnaces.Of interest and discussed in detail are the 32-foot autogenous cascade mills ."

Jan 1, 1970

By L. W. Vollmer

Introduction During the past three years at least fifty strings of 9% nickel steel tubing have exhibited excellent resistance .to the variably severe corrosive conditions typical of many of the sweet condensate wells in Mississippi, Louisiana, and Texas. This experience, and the characteristically outstanding performance of other ?nickel alloy steels under hydrogen sulphide corrosive conditions, dictated the selection of 9% nickel steel tubing for the second well drilled in the sour condensate Pincher Creek field of southwestern Alberta. The damaging effects of the Pincher Creek reservoir fluids on well equipment had been manifested in the discovery well by the rapid and not yet fully understood failure of API Grade N-80 tubing, stainless steel wire lines, and alloy steel fishing tools. Two very unexpected failures in the 9% nickel steel tubing, after only six days of service in production tests, instigated an extensive and continuing investigation to ascertain the probable cause of failure. This discussion presents some of the results obtained thus far which cast a little light on the perplexing behaviour of steels in hydrogen sulphide environments in general, and in sour condensate wells in particular. History of Tubing Failures Walter Marr well No. 1, in which the 9% nickel steel tubing failures occurred, produces from the Madison lime at the depth interval approximately 12,200 to 12,750 feet. The gas-oil ratio is about 26,000 and the gas contains 10.2 per cent hydrogen sulphide and 6.3 per cent carbon dioxide by volume.

Jan 1, 1952

By K. V. Lindell

Introduction This paper describes a recent innovation in the design and construction of mine headframes. A reinforced concrete headframe was built by using sliding forms. A concrete headframe of conventional design was originally considered, but investigation of this project showed that it was doubtful if the bearing strength of the soil was sufficient to support the great weight of a structure of this type. In addition, the slope and the fractured condition of the serpentine bed-rock did not permit satisfactory piling. A conventional steel headframe with storage bins was then designed, but, due to the steel situation, delivery promises were set back many months. The concrete headframe was again investigated, and a design was adopted incorporating a circular headframe lower in height than that first considered, with skips discharging into a smaller surge bin. The upper section of the shaft collar was strengthened to result in a stable structure which would be supported by bed-rock, as well as by the concrete and steel lining of the shaft itself.

Jan 1, 1948

By Jean A. Bastien

Cette présentation décrit les étapes de développement et l?exploitation souterraine au puits Penna chez Agnico-Eagle division Laronde. Les sujets suivants sont touchés : le fonçage du puits, le développement des niveaux, la méthode d?exploitation, la manutention de la roche brisée, le méthode de remblayage et la ventilation. En résumé : le fonçage du puits s?est fait sur 2,240 mètres de novembre 1995 à mars 2000. Le développement des niveaux a débuté en octobre 1998. Les opérations de minage ont débutés en août 99 dans le premier horizon situé au dessus du niveau 122. Les chantiers sont exploités par longs-trous d?environ 25 mètres de long avec un diamètre de 10 cm. Les accès à la zone minéralisée sont transverses. Le minerai est soutiré des chantiers et acheminé au passe-minerai a l?aide de chargeuses navettes. Par la suite, le minerai passe sur un marteau, est concassé et transporté sur un convoyeur, jusqu?au silo de 4,500 tonnes au-dessus de la station de chargement automatisée du niveau 152 d?ou les skips sont alimentés. Le remblai en pâte est envoyé de la surface par des trous ayant un revêtement d?acier. Le diamètre intérieur est de 15 cm. Le réseau de ventilation est principalement alimentée par des ventilateurs de surface (système aspirant et souflant) conçus pour acheminer sous-terre un maximum de 640 mètres cubes par minutes (1,350,000 pcm).

May 1, 2001

By Gregg W. Morrison

"The Craigmont copper-iron skarn deposit is adjacent to the southern margin of the late Triassic Guichon Creek batholith in south-central British Columbia. Host to the ore are sedimentary and volcanic rocks of the western calc-alkaline belt of the Upper TriassicNicola Group. In the mine area, the Nicola Group rocks are a stratigraphically complex sequence, at least 1800 feet thick, which have been subdivided into Basalt, Rhyolite, Carbonate and Clastic Sediment units. All the units strike and dip parallel to the margin of the Guichon Creek batholith and are within the batholith contact aureole. However, only the Clastic Sediment unit is in contact with the batholith.Most of the skarn and ore is within the Carbonate unit and more specifically within an Interbedded facies that consists of lime sandstone, lime siltstone, quartzo-feldspathic siltstone and argillite. The Interbedded facies and the adjacent barren Massive Limestonefacies are interpreted aspart ofa carbonate reef complex. The distribution of skarn and ore within the Interbedded facies suggests that the facies boundary was a physical and chemical barrier that resulted in concentration of metals adjacent to the Massive Limestone facies.Two stages of skarn formation have been recognized at Craigmont. In Stage I, ore-bearing magnetite-rich and actinolite-epidote-magnetite skarns developed both in basaltic rocks and in Fe-bearing siltstone and argillite of the Interbedded facies, while barren grossular garnet-epidote-calcite-pyrite skarns developed in Fe-poor rhyolitic bands within the Interbedded and Massive Limestone facies . In Stage ll, massive, barren grandite garnet skarn replaced mineralized Stage I skarns in the vicinity of diorite plugs. and specularite ore formed in brecciated Stage I skarn and clastic rocks away from the plugs. Theformation of Stage I skarns required no addition of material, only redistribution and concentration of elements already present within the Interbedded facies. However, the concentration of Cu in Stage lore requires a mechanism for more efficient leaching of Cu from the host rocks, an anomalous concentration of Cu at the site of the Stage I orebody or an additional input of Cu from an external source. The formation of Stage II skarn and ore requires only remobilization and recrystallization of Stage I skarn and ore.Copper and iron are the only elements in economic concentrations in the ore and chalcopyrite is the only significant copper-bearing mineral. Chalcopyrite is disseminated and interstitial to magnetite in Stage I mineralized skarns and is interstitial to specularite in the matrix of Stage II breccia ores. Chalcopyrite also occurs with pyrite as stringer ore in bleached • sediments and rhyolite tuffs in the stratigraphic footwall of the main orebodies.The Craigmont deposit has more features in common with Cu-Fe deposits hosted in metavolcanic and metasedimentary rocks than it has with typical skarn deposits associated with porphyry copper deposits. The orebody is more likely a product of concentration of metal contained within the Nicola Group rocks than of the mineralizing event that produced the . Highland Valley Cu-Mo porphyry deposits in the central part of the Guichon Creek batholith ."

Jan 1, 1980

By B. A. Zaharov, J. M. Shneerson, L. V. Chugaev, M. T. Zhunusov, A. M. Markelov, S. V. Drozdov

The main direction of research was the application of autoclave technology for the flotation concentrates or biooxidation feedstocks. The industry modernization also expects the possibility of increasing the yield of the flotation concentrate, to allow an increase in gold extraction in flotation circuit. This paper provides brief description of results obtained for concentrates with the yield of 4 and 8%, as well as corresponding biooxidation feedstocks. Technological efficiency of autoclave oxidation is shown for both concentrates and biooxidation feedstocks. The process has been evaluated on a laboratory and a continuous pilot plant scale. Gold extractions from POX discharge are ranging from 94-97% for each product, with only 5-7 kg/t cyanide consumed.

Jan 1, 2014

By A. Becker, C. Gauvreau, L. S. Collett

"A scale model was designed to simulate the airborne Barringer INPUT time domain electromagnetic system. The amplitude of the response to a vertical conductive dyke varies considerably with the conductor's thickness conductivity product (TCP). The response increases from a minimum detectable level at a TCP of about 2 mhos, rises to its maximum value at a dyke TCP of 15 mhos and then falls again so that conductors with a TCP exceeding 500 mhos would probably remain undetected. Measurements made with both standard receiver coil configurations (maximum or minimum coupled) indicate comparable effectiveness for both systems, either from the viewpoint of vertical conductor detection or from the viewpoint of discrimination against overburden anomalies."

Jan 1, 1972