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By M. S. Badollet, W. C. Streib

"AbstractA commercial method .has been developed for controlling the texture of chrysotile asbestos fibers so that they may possess properties comparable with natural sem1-harsh fibers for use in wet •processes.The physical properties of the soft, silky and slimy fibers are partially altered by a flash-heating process which removes a portion of the molecular water.The heat-treated fibers show an improvement in filterability, an increase in bulk, absorption, and surface area and better electrical properties, such as volume resistivity.IntroductionCHRYSOTILE ASBESTOS fibers are found in nature having varying degrees of texture, referred to as soft, semi-harsh, and harsh. Fibers of each type of texture have inherent characteristics which directly affect their usefulness to industry. Visual differences are apparent under a microscope where it is seen that the soft-textured fibers have a silky, serpentine or wavy appearance, whereas the harsh-textured fibers are coarser and spicular. Semi-harsh fibers, of course, have properties intermediate between these extremes.Fankuchen and Schneider ( l) have shown by the use of low-angle X-ray scattering that the diameter of the harsh type of chrysotile fiber is somewhat greater than tha of the soft variety. Surface area measurements on various chrysotiles of different textures tend to confirm their findings. By nitrogen adsorption methods, it was found that the surface areas of soft types of chrysotile asbestos are approximately 23M2 / g whereas for the harsh types they are as low as 11M2/g."

Jan 1, 1955

By Craig Roberts

"While various methods are available to estimate a mining project's value, value is only established through a transaction. Comparable methods allow the value estimated for a mining project to be benchmarked against mining project values established in the market. Comparable methods thus are a key tool for ensuring value estimates are congruent with what the market would actually pay. For example, if the value estimated for a mining project using discounted cash flow analysis differs significantly from the value implied using comparable market methods, the valuator may be using metal price or discount rate assumptions that differ significantly from those the market is currently willing to pay for.The paper provides an overview of market comparable valuation approaches, and discusses some of the difficulties and limitations that arise in using these approaches. The types of market values that are typically utilised are discussed, including asset sale prices, share prices (market capitalisations), and values established in corporate mergers and acquisitions. Topics discussed include methods used in estimating a mining project's value based on the market value of the company that holds the asset, and limitations that arise because of unique features of mining projects and of companies that hold them.It is concluded that market comparable and fundamental (e.g. NPV) approaches to project valuation should not be viewed as alternative approaches to estimating project value, but rather can and should be integrated to derive a single value estimate based on both market andfandamental data. A method for integrating these approaches is discussed, and illustrated by example."

Jan 1, 2003

By W. N. Hamilton

As a result of a test-drilling program conducted by the Research Council of Alberta in 1968, a gypsum deposit averaging 30 feet in thickness, with a chemical purity of 84 per cent gypsum, has been proven to underlie the Clearwater River valley for a distance of 18 miles at depths ranging from near-surface to 300 feet. This and other subsurface deposits in the vicinity of Fort McMurray, Alberta are the product of local hydration of anhydrite beds believed to be the water-insoluble remains of the leached Prairie Evaporite formation of Middle Devonian age, the thick salt section of which is preserved down dip. The effects of salt solution are seen in the disturbed bedding and the intermixture of greyish green shale with gypsum in the core, the shale content being responsible for the rather low chemical purity of the deposit. A similar gypsum deposit, but probably of higher purity, is postulated to occur beneath the Athabasca River valley about 60 miles north of Fort McMurray.

Jan 1, 1969

By C. O. Stee

Introduction The property of Siscoe Gold Mines, Limited, is located on an island of three hundred and forty acres in lake Kienawisik, about fifty-two miles east of Noranda and forty-three miles south of Amos, Quebec. Lake Kienawisik is a part of the Harricanaw drainage system and is crossed by the main line of the Canadian National railway at Amos. This waterway is navigable for boats with a draught of six to eight feet. Diesel engines have been the source of power at the property since milling operations were commenced in January, 1929. The power plant as first designed and built was for a milling capacity of 100 tons. Two Polar-Atlas units, each of 200 h. p., comprised the original installation. With the growth of the 'mine, more engines were added until, at the present time, there is installed at the Siscoe what is rated the largest Diesel plant at any mining property in Canada. Definition of a Diesel 'The Diesel engine is an internal combustion engine which works with liquid fuel introduced after, and independently of, the air charge at a time when communication between the cylinder and the outside atmosphere is cut off, and which ignites the fuel by compression-beat and stored combustion-heat unassisted by heat sources outside the cylinder itself while the engine is in stable operating condition"(1).

Jan 1, 1934

By A. R. Farkoosh

Al-Si based alloys have been recently used by automotive industry for highly stressed engine applications. Due to severe working conditions of the engine parts, existing alloys hardly endure high pressures at high temperatures. This necessitates alloy modifications to enhance the elevated temperature performance. In this study, the effects of trace nickel additions on the microstructural and mechanical properties of A356+0.5Cu alloy have been investigated at different aging conditions. Electron probe microanalysis (EPMA), scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to study the microstructural changes. Aging curves have been obtained by hardness measurement. It was seen that the presence of additional nickel introduced many complex intermetallic phases within the microstructure which led to improved high temperature mechanical and aging response.

Jan 1, 2011

By H. W. Smith, C. L. Lewis

"A process control computer has been installed in the Lake Dufault concentrator to: (a) control the on-stream X-ray analyzer and convert chart readings to elemental percentages, (b) calculate the flow rates required for the most important flotation reagents, using the amount of material entering the process, the analyses and the slurry pH, and (c) set the reagent feeder to these flow rates automatically. Although this project was largely experimental, to gain knowledge and experience in flotation process control, the objectives have been met and fully automatic computer control is now the normal mode of mill operation.This paper describes project planning and defines the system with respect to both control design and functional design. System operation -as seen by the mill operator -is detailed. Implementation of the system is described and the system is discussed in terms of its success, economic justification and future plans."

Jan 1, 1969

By Elma van der Lingen

Gold is considered the most inert of all metallic elements, but the metal can show catalytic activity when prepared by specific techniques. Preparation techniques being used to prepare gold catalysts systems mainly involve precipitation methods incorporating gold compounds or complexes. This paper introduces a totally different method for the preparation of gold-based heterogeneous catalysts that can be used for oxidation and reduction reactions, as well as electrocatalysts. The method involves alloying of gold with a less noble metal, such as aluminium, to form a gold-containing intermetallic precursor. AuAl2 was produced by melting gold and aluminium together in a vacuum arc furnace under a protective atmosphere. The aluminium is then dissolved from the AuAl2 precursor by means of NaOH to produce a highly porous gold structure. The paper also reports on a method of incorporating transition metal oxide(s) with the porous gold to form an active heterogeneous catalyst. Promoter elements can also be melted with AuAl2 to improve catalytic activity. Alloying has the advantage that the promoter element can be in contact on atomic level with the gold. In-situ xray photoelectron spectroscopy (XPS) studies have also been done on the porous gold catalysts to further clarify the CO oxidation mechanism on gold-based catalysts.

Oct 1, 2003

By John D. Godfrey

A brief account of economic developments in and around northeastern Alberta is presented and mention is made of mining and industrial developments currently of interest in the area. Planned and projected operations are briefly discussed for this region. The history of geological surveys and mining activities in the Shield area of Alberta and the adjoining parts of Northwest Territories and Saskatchewan is traced. Reassessment of the presently-known economic picture of northwestern Canada in conjunction with some recent information on Precambrian structures of northeastern Alberta points to some interesting mining possibilities, particularly in and around that province.

Jan 1, 1960

By P. Clinton Milne

Uranium mines in Washington State include the producing Midnite and Sherwood mines and several mined-out deposits, the most productive of which was the Daybreak mine. The Midnite mine is generally classified as a hydrothermal deposit consisting of tabular orebodies in Precambrian pelitic and calcareous metasedimentary host rocks. The host rocks occur as roof pendants in a Cretaceous porphyritic quartz monzonite intrusive; the quartz monzonite averages 12 ppm U308 The uranium deposit appears to have undergone a complex genesis, involving a series of depositional and enrichment stages. The Sherwood uranium deposit, approximately 4 miles south of the Midnite mine, occurs near the bottom of a basal Late Cretaceous to Paleocene arkosic conglomerate. The conglomerate lies nonconformably on the porphyritic quartz monzonite that is associated with the Midnite deposit. The Sherwood and Midnite uranium deposits may have had a similar genetic history linked by a common uraniferous pluton source, ground-water action, and/or leaching of uranium-rich ash flows from now-eroded, overlying, Eocene volcanics. The Daybreak deposit, in northeastern Spokane County, consists entirely of secondary uranium mineralization (metaautunite) in a quartz monzonite pluton. Mineralization is confined to a low-angle fault zone and is most highly concentrated at the intersection of primary and secondary shears. Both hydrothermal and ground-water origins are feasible. Besides the Midnite-Sherwood area, 14 other areas in the western Okanogan Highlands physiographic province and Cascades region have favourable characteristics for uranium potential. Criteria include the existence of uranium occurrences, Tertiary basin sediments with intercalated volcanic and volcaniclastic rocks, favourable geochemical data, alkaline plutons associated with uranium occurrences or borders of Tertiary basins, and structural controls.

Jan 1, 1979

By B. C. Tripathy, S. K. Padhy, R. K. Paramguru, Pinak Patnaik

"Cobalt is regarded as technology enabling metal among the less abundant metals found in the earth crust. Electrodeposition of the metal from aqueous sulphate solutions is the preferred technology for its commercial production. Certain additives are added in the electrolytic bath during electrodeposition for the production of uniform, smooth and bright deposits of cobalt metal with higher current efficiencies and lower energy consumptions. A detailed investigation has been carried out to determine the effect of additive Sodium octyl sulphate (SOS) on the electrodeposition of cobalt. The results indicated that the additive apart from increasing the current efficiency enhanced the quality of cobalt electrodeposits. A maximum current efficiency of 98.4% was achieved at 10 mg/L SOS. The presence of SOS in the electrolytic bath did not result in any noticeable change in the crystal orientation of the cobalt electrodeposits except at higher concentrations (50 g/L) of the additive. Scanning electron micrographs indicate that smooth, compact and uniform deposits of cobalt were obtained at 10 mg/L of the additive beyond which there is detoriation in the quality of deposits. Polarisation of the cathode was seen in the presence of SOS. The effect of SOS on the electro kinetic parameters: Tafel slope (b), transfer coefficient (a) and exchange current density (I0) has also been investigated.INTRODUCTIONCobalt is recognised to be a strategic metal among the various base metals, owing to its numerous applications in various industries. Cobalt as a metal finds its use in the preparation of rechargeable batteries, as an alloying component in the manufacture of space craft and jet engines, as a drying agent for paint varnishes, ground coats for porcelain enamels and in the manufacture of the catalysts for the petroleum and chemical industries (Davis, 2000). Although there is a huge demand of the metal the supply of the metal is limited due to its scarcity in the earth crust. The metal comprises of only 0.02% of the earth’s crust for which the metal is recovered from various ores of nickel and copper as a byproduct (Hawkins, 1998). The present day techniques for cobalt production includes mostly hydrometallurgical methods which are preferred over the earlier used pryometallurgcial methods carried out for the metal production. Almost 70% of the world’s cobalt produced currently is from hydrometallurgical techniques in which electrodeposition of the metal from aqueous solutions is the final step for metal production (Verney, 1988). The most preferred route for electrodeposition of cobalt metal involves a sulphate medium (Das and Subbaiah, 1984; Lenthall and Bryson, 1997; Sharma et al., 2005)."

Jan 1, 2016

By Teresa Sikora

For over 40 years the Institute of Innovative Technology EMAG has specialized in the development of systems and equipment for laboratory and on-line monitoring of coal quality parameters, as well as the implementation of these systems and devices in mines and power stations. Some of these systems, based on advanced radiation detection techniques such as ?-ray backscattering (ALFA-06 and ALFA -06/T systems) or dual energy ?-ray transmission measurement (ALFA-06/2E ash meter), and also the ALFA-06/3E system applying microwave technology for the measurement of moisture, have had numerous applications in Poland. At present, over 100 systems and devices are used in Polish hard and brown coal mines. For over 10 years, EMAG has been specializing in the development of systems and devices, based on natural gamma measurement technology. An on-line ash meter, RODOS and RODOS Ex, based on measurement of natural gamma radioactivity of coal, has been developed and put into operation. This technique has been also used in developing the portable ash meter WALKER and laboratory analyzer GAMMA NATURA. The paper briefly presents features of the above-mentioned devices, their limits and their obtained accuracy, but in particular refers to the laboratory analyzer, GAMMA NATURA, as the first such device in the world, and presents the results of ash and moisture content measurement in hard, brown coals and potassium salts. The possible applications and advantages of the device in coal mines are discussed. The paper also presents the implementation results of the portable ash meter, WALKER, and the on-line ash meter, RODOS, that is used underground in coal mines.

Aug 1, 2013

By J. F. Davis

Pegmatite dykes containing lithium minerals and beryl occur dose to the borders of intrusive masses of granitic rock in the Winnipeg River area of Manitoba. Both vertical and flat-lying dykes are present. Most of the pegmatites consist of zones, containing characteristic mineral assemblages, arranged more or Jess parallel to the borders of the dykes. Five important lithium minerals are present; each occurs in a separate zone, but all the lithium-bearing zones are situated toward the centres of the pegmatites. Spodumene is the most abundant and widespread of the lithium minerals and occurs as small crystals intimately intergrown with quartz. Beryl is not an important constituent of the lithium pegmatites, but when .present, occurs outside the lithium zones, toward the margins of the -dykes. Beryl is most common in dykes containing few or no lithium minerals. The mineral assemblage in the beryl zone of the lithium dykes is the same as that of the beryl dykes. The attitude and internal structure, particularly zoning, of the pegmatite dykes, and the texture and assemblages of the constituent minerals, have an important bearing on exploration, development, and mining of these pegmatites, and on the extraction of various mineral products from them.

Jan 1, 1958

By Rodrigo Serna-Guerrero, Ted Nuorivaara

"As the demand of raw materials increases in a global scale due to demographic and economical changes, it is necessary to find technological solutions that improve current production processes in an efficient and sustainable manner. The main objective of this preliminary study is to evaluate the properties of foam produced with a cellulose-based molecule as an alterative to commercial frothing agents in flotation operations. There are two potential advantages identified with the use of cellulose-based additives for the proposed application: i) these chemicals can be produced from sustainable sources (i.e., non-edible crops), and ii) cellulose can be functionalized with chemical groups, in order to rationally modify its behaviour. In previous studies dealing with foam stabilization, it has been proposed that some functionalized cellulose species present a self-assembly mechanism at gas-liquid interfaces. Unlike typical surfactant-based frothers, cellulose molecules form networks around the bubbles that act as protective layers to the mechanical stress and to the occurrence of ionic species. This work studied the properties of foams produced in the presence of a partially hydroxylated cellulose molecule (i.e., hydroxypropyl methyl cellulose; HPMC) under various concentrations in a laboratory-scale column. A comparison with a commercial surfactant frother (i.e., Nasfroth 240) is presented, and a rationalization of the behaviour of HPMC in terms of foam properties (i.e., surface tension, bubble size, foam depth) is proposed. INTRODUCTIONThe search for green alternatives to chemicals produced from non-renewable sources has become a topic of major relevance in industry (Choi et al., 2015). As a chemical consuming industry, the mining sector faces now the challenge of adopting new processing technologies and strategies in order to achieve the future demands of sustainability. Evidently, a move towards green chemistry can only take place by identifying substitute molecules offering potential advantages in terms of recovery and grade."

Jan 1, 2016

By G. A. Pinsky, Pickard M. K

"IntroductionTWO METHODS of mucking have been used in sinking C shaft, the five-compartment production shaft of the Yellowknife property of Giant Yellowknife Gold Mines, Limited:(a) Band mucking during the original sinking in 1949 and 1950 (l); and(b) Mechanical mucking with the Cryderman shaft mucker during the recent deepening in 1954.This paper briefly describes the recent deepening and compares the performance figures of the two sinking operations.PlanningProduction planning in 1952 showed that it would be advisable to deepen C shaft in 1954 to provide for three new production levels and the installation of an underground crusher. To complete the required shaft work it would be necessary for a shaft crew to deepen the shaft about 500 feet, to partly excavate three level stations and a crusher station, and to cut a station for the loading pocket. Figure 1, a vertical section of the lower part of the shaft, shows the details of the deepening programme.During the planning period, Giant had a rather small supervisory staff and at the same time was experiencing a heavy labour turnover. As it was obvious that production would suffer if the sinking crew were recruited at the mine, it was decided that the merits of contracting-the shaft sinking to an independent contractor should be investigated."

Jan 1, 1955

By Neil Campbell

"The gently-dipping Devonian dolomite beds south of Great Slave lake in northern Canada are nearly every-where concealed by a cover of glacial drift and muskeg. Nevertheless, in 1898 or earlier, four small outcropping areas of dolomite, richly mineralized with lead and zinc sulphides, were discovered. Exploration work performed here up to the end of 1930, included intensive trenching and drilling of the showings, together with mapping and wide-spaced drilling in the surrounding region. This work proved that the discoveries are isolated pockets of mineralization much too small to be commercially valuable by themselves. No evidence of orebodies elsewhere was reported.Meanwhile, mapping by the G.S.C. in the Shield far to the east disclosed major Precambrian faults, some of which can be projected southwesterly (under a cover of Paleozoic sediments) to the vicinity of Pine Point. During the period from 1940 to 1947, consideration was given, by The Consolidated Mining and Smelting Company Ltd., to evidence of a theoretical possibility that, although apparently dormant in Paleozoic times, these faults may have provided a structural control and a source of ore-bearing solutions in some post-Devonian period. From this, it was postulated that the breaks might have created, in the overlying dolomite, a linear array of orebodies concealed by overburden but lying in a belt of considerable length and in a position predictable within practical limits. A program of drilling designed to test and exploit this specific concept was conducted from 1948 to 1955.he drilling within the new, theoretically-defined search area resulted in the discovery of many lead-zinc ore-bodies, none of which was exposed at the surface. Some of these are large and (as indicated by 1965 production records) very rich. They are situated 1 to several miles distant from, and apparently not connected to, the earlier-known surface discoveries. The drilling also disclosed that the ore, which consists of disseminated sphalerite and galena replacements together with colloform sphalerite and coarse galena cavity fillings, occurs mainly at certain stratigraphic horizons within a large, coarsely-recrystallized dolomite barrier reef. Considerable fracturing and folding was found. It has been suggested that reef development was influenced by post-Precambrian tectonic movements associated with the old faults in the basement complex. The ore may have been deposited by solutions moving from distant sources to favourable structural and chemical environments in or related to the reef.In more recent exploration performed in the course of preparing for mining production, the rate of ore discovery within the same general geological context has been greatly accelerated by the use of new geophysical techniques and drilling equipment. Reserves of 21.5 million tons, averaging 4 per cent lead and 7.2 per cent zinc, were reported in 1965, and production from open pits at the rate of approximately 248,000 tons of concentrates per year is in progress"

Jan 1, 1966

By E. A. G. Colls

PART I.-GASES IN INDUSTRY INTRODUCTION THE part played by gases in industry can be considered from at least four distinct viewpoints, viz: (1) As air to support combustion and life and do various kinds of work (2) As fuel, or as essential to certain chemical processes (3) As sources of danger from explosion or fire ( 4) As hazards to man's health The present paper deals with gases only insofar as they are sources of danger, or are hazards to health. It may be noted, however, that, in point of tonnage, air is one of the most important materials handled in any industrial plant. In the operations of the Consolidated Mining and Smelting Company, for example, 138,000 tons of air are handled daily, the only material exceeding this figure being water. The United States Bureau of Mines has listed no fewer than seventy-four gases and vapours that, under certain conditions, may be considered as ex-plosive or dangerous (poisonous). The commonest and most important of these are as follows : Carbon monoxide Methane Acetylene Hydrogen Oxygen Hydrogen sulphide Benzol vapour Ammonia Petroleum vapour Carbon disulphide Hydrochloric acid gas Cyanogen Carbon oxysulphide Chlorine ` Fluorine (and fluorides) Acetone vapour Acetic acid vapour Water gas Natural gas Gasoline vapour Coal gas Producer gas Ether vapour Nitrogen oxides

Jan 1, 1940

By J. M. Janssens, Van Quach Tinh, M. Ruel, R. Leblanc

"Microscopic studies of peat moss indicate a highly porous material. In view of using this natural product as an adsorbing agent for the treatment of polluted water, studies of its adsorbing power for beef extract and alkyl benzene sulphonate solution were determined. The effects of time of contact, particle size, concentration of adsorbent and concentration of pollutant were studied. In the case of beef extract, there is a COD reduction of around 27 per cent; in the case of the alkyl benzene sulphonate, the percentage reduction varied from 72 to 95 per cent. A water treatment plant based on the adsorbing power of peat moss with simultaneous recuperation of the pollutant is proposed."

Jan 1, 1971

By Alain Simard, André Gobeil, Sylvain Lacroix, Maurice Rive, Denis Racicot, Pierre Verpaelst

"The Abitibi volcano-plutonic belt forms the major portion of the Abitibi lithotectonic subprovince in the Superior Province. The Abitibi belt is composed essentially of"" (1) approximately 2.7 Ga old volcanic and sedimentary rocks; and (2) gabbro, tonalite, granodiorite and syenite intrusions occurring in well-defined prekinematic ( synvolcanic ), synkinematic and post-kinematic plutonic suites. Most of these rocks are metamorphosed to greenschist facies. Regional multi-phase deformation affects the volcano-sedimentary rocks. Deformation was initiated as these rocks were formed, and peaked at the end of the Keno ran orogeny with the emplacement of granitic batholiths.There are 145 former and current mines in the Quebec segment of the belt. To date, more than 420 Mt of ore have been extracted yielding 1,600 tonnesof Au, more than4,000 tonnesof Ag,4,400,000 tonnes of Cu and 5,300,000 tonnes of Zn. Mineral production is concentrated in geologic domains that approximately coincide with the boundaries of lithotectonic domains. We have compared the geology and mineral deposits of different domains to illustrate their distinct metallogenic signature. Certain domains are dominantly gold-producing (Cadillac-Malartic, Val-d'Or, Caopatina), others are base-metal producers (Matagami and Normetal), while others produce both gold and base metals ( Rouyn-Noranda, Chibougamau, Casa-Berardi-Joutel).Gold is extracted from quartz-rich vein deposits (for example, Val-d' Or), sulfide-rich veindeposits(Cadillac or Chibougamau) and from volcanogenic massive sulfide deposits ( Rouyn-Noranda). Base metals are generally mined from volcanogenic massive sulfide( RouynNoranda, Matagami, Normetal), although certain vein deposits yield base metals (Chibougamau) . Certain sectors are dominantly zincrich (Matagami, Normetal)."

Jan 1, 1990

By V. T. Panayotov, M. I. Panayotova

Wastewater from mining and mineral processing activities is often polluted by anion forming metals, such as molybdenum and chromium. Low cost materials, including zeolites, are studied for removing heavy metals from wastewater. It is widely accepted that natural zeolites are not effective in removing metals in anionic form. The paper presents study on use of metal modified natural clinoptilolite to remove Mo (VI) and Cr (VI) ions from model soft wastewater. Modification with Pb, Fe(III), Zn and Ba increases clinoptilolite uptake capacity with respect to Mo(VI) at low pH values of the water subjected to treatment, the efficiency decreasing in the order Pb > Fe(III) > Zn > Ba. Only lead-modified clinoptilolite shows high uptake of Mo(VI) in acidic, neutral and slightly alkaline conditions. Modification with Pb, Ba and Fe(III) increases zeolite uptake capacity with respect to Cr(VI) from neutral water. The effectiveness of Ba-modified zeolite decreases in slightly acidic water. Over 90 % uptake of initially available Cr(VI) is achieved by lead-modified clinoptilolite both under neutral and slightly acidic conditions. Increasing the initial pollutant concentrations increases the removed amount both of Cr(VI) and Mo(VI) for Pb-modified clinoptilolite. The findings could be a basis for using the natural clinoptilolite to remove in consecutive steps: firstly Pb(II) and/or Fe(III) ions and then loaded zeolite to be used for Mo (VI) and/or Cr(VI) removal. The kinetics of Mo(VI) uptake by CL-Ba, CL-Fe(III), CL-Pb, and CL-Zn is best described by the pseudo-first order kinetic equation. The kinetics of Cr(VI) removal by CL-Ba, CL-Fe (II), CL-Fe (III) and CL-Zn is best described by the pseudo-first order kinetic equation. Kinetics of Cr(VI) removal by CL-Pb obeys the equation for the first order irreversible reactions. Finding way to remove anions-pollutants from the mineral processing wastewater will render this industry more environmentally friendly and socially acceptable.

Jan 1, 2016

By Alain Simard, Andre Gobeil, Sylvain Lacroix, Maurice Rive, Denis Racicot, Pierre Verpaelst

"The Abitibi volcano-plutonic belt forms the major portion of the Abitibi lithotectonic subprovince in the Superior Province. The Abitibi belt is composed essentially of"" (1) approximately 2.7 Ga old volcanic and sedimentary rocks; and (2) gabbro, tonalite, granodiorite and syenite intrusions occurring in well-defined prekinematic ( synvolcanic ), synkinematic and post-kinematic plutonic suites. Most of these rocks are metamorphosed to greenschist facies. Regional multi-phase deformation affects the volcano-sedimentary rocks. Deformation was initiated as these rocks were formed, and peaked at the end of the Keno ran orogeny with the emplacement of granitic batholiths.There are 145 former and current mines in the Quebec segment of the belt. To date, more than 420 Mt of ore have been extracted yielding 1,600 tonnesof Au, more than4,000 tonnesof Ag,4,400,000 tonnes of Cu and 5,300,000 tonnes of Zn. Mineral production is concentrated in geologic domains that approximately coincide with the boundaries of lithotectonic domains. We have compared the geology and mineral deposits of different domains to illustrate their distinct metallogenic signature. Certain domains are dominantly gold-producing (Cadillac-Malartic, Val-d'Or, Caopatina), others are base-metal producers (Matagami and Normetal), while others produce both gold and base metals ( Rouyn-Noranda, Chibougamau, Casa-Berardi-Joutel).Gold is extracted from quartz-rich vein deposits (for example, Val-d' Or), sulfide-rich veindeposits(Cadillac or Chibougamau) and from volcanogenic massive sulfide deposits ( Rouyn-Noranda). Base metals are generally mined from volcanogenic massive sulfide( RouynNoranda, Matagami, Normetal), although certain vein deposits yield base metals (Chibougamau) . Certain sectors are dominantly zincrich (Matagami, Normetal)."

Jan 1, 1989