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By B. W. Smee

Glacial lake sediments or glaciolacustrine deposits form a significant portion of the Canadian, Scandinavian and Russian landscapes. Furthermore, 50 per cent of the Archean volcanic belts within the Canadian Shield area are covered wholly or in part by these deposits. Because of the high electrical conductivity and low hydraulic conductivity of these compact sediments, the application of geophysical (electrical) and geochemical techniques in such areas becomes a difficult task. The presence of these sediments has therefore hampered exploration for metallic sulphide deposits in some of the most important metallogenic environments of Canada. Similar problems exist in some tropical countries, such as Australia, where the overburden may be very conductive. In this paper, the extent and provenance of the glaciolacustrine deposits within the Canadian Shield are described. The geochemical and geophysical factors that hinder exploration in the clay belts are reviewed, with case histories of successful and unsuccessful applications of some of these techniques. The most successful geochemical technique used within glacial clay belts is the sampling of lodgement till beneath the clay cover, and the analysis of the heavy mineral fraction of that till. Surficial sampling has not been successfully applied. Some geophysical techniques, more specifically electromagnetic and magnetic induced-polarization techniques, have detected mineralization beneath substantially deep clay or saline overburden layers. Some suggestions have been made, such as the use of anions in hydrogeochemical surveys and the use of wide-band multi-frequency EM systems. When implemented, they will hopefully make the current geochemical and geophysical methods more effective in exploration for base metal sulphides within clay-covered terrains.

Jan 1, 1979

By John C. Lyons

"The Wabana iron ore deposits occur as flat-dipping beds of oolitic hematite and chamosite, of Lower Ordovician age, which outcrop for 3 miles along the northwest coast of Bell Island, Conception Bay, Newfound-land, about 16 miles from St. John's.The deposits occur in three zones, Upper, Middle, and Lower beds, separated respectively by 30 feet and 215 feet of shale and sandstone. They are primary sediments laid down in a shallow tidal basin by the precipitating action of a marine environment on iron-rich fresh waters flowing into the basin.The ore-bearing zones, while of wide areal extent, are not uniform beds of hematite that can be mined wholesale. The action of waves and currents during sedimentation; the delta pattern, velocity, and transporting power of streams flowing into the basin; the contours and oscillations of the sea bottom on which the sediments were laid have all been fundamental in the emplacement of richer and thicker mineable sections, and of lean zones so intercalated with shale as to be unmineable.The preservation of the deposits is due to their location in the Conception Bay syncline and to a considerable upthrust of the country east of the bay in post-Ordovician time.The hematite deposits were first recognized as such in 1892, and soon after were acquired by the Nova Scotia Steel and Coal Co. They are now being mined by Dominion Wabana Iron Ore, Limfred, a wholly owned subsidiary of the Dominion Steel and Coal Corporation, Limited. Production started in 1895, and up to the end of 1955 totaled 58,588,516 long tons of hematite ore, having an average dry analysis of about 51 5 per cent iron, 11 8 per cent silica, 0·9 per cent phosphorus, and l ·5 per cent moisture. About 40 per cent of the total tonnage mined has come from surface stripping and on-shore mines. These areas have now been almost completely depleted, and operations are confined to submarine mines extending for two miles off shore under the waters of Conception Bay. Three sub-marine slopes are currently in operation, Nos. 3 and 4 working in the Lower Bed and No. 6 in the Middle Bed. A general picture of the workings is shown in isometric projection in Figure 1. Submarine mining has been entirely by the room-and-pillar method, with an extraction of 60 per cent. The deepest workings, at a vertical depth of 1,850 feet below sea-level, have a rock cover of about 1,500 feet. No mining is done in areas where the rock cover is less than 200 feet. To date mining has explored six square miles of a potential area that may exceed 50 square miles."

Jan 1, 1949

By Steve Lalancette

Centre Jardin Lac Pelletier (CJLP) has been a leading actor in the revitalisation of closed mining sites in northern Québec for over 20 years. Over that period, CJLP developed a cost-efficient technique that transforms sterile mining residue into a substrate able to support a resilient ecosystem. Using a unique mix of organic matter, fertilisers and selected plant species, this technique rapidly builds a microorganic fauna and a layer of humus that will sustain the creation of vegetation coverage. The coverage is composed of over 13 different plant species, each having a unique role in the development of a resilient ecosystem, from soil stabilisation to nitrogen fixing. Considerably less expensive than traditional methods using civil engineering techniques, it does not require the use of heavy machinery or the spread of topsoil. This technique has been successfully used to restore over 20 sites in Québec such as Joutel, Yvan Vézina and Louvicourt. It is a proven technique that has passed the test of actual implementation. The presentation will review the biological, production and economic aspects of the technique through the revitalisation of the Joutel site.

May 1, 2011

By Baki Özüm

Early evaluations of Pasquia Hills kerogen shale deposits by Geological Survey of Canada, Saskatchewan Geological Survey, Manitoba Energy and Mines and Sun Oil Company, using modified Fischer Assay, Rock-Eval and other techniques, estimated recoverable reserves of about 2.6x109 barrels of oil in areas favorable for strip-mining; each metric ton of ore was determined to yield about 30 L to 50 L of shale oil remarkably high in aromatic compounds. Western Petrochemical Corp. (WPC) is holding two Oil Shale Exploration Permits covering about 76,635 hectares in the Pasquia Hills Region of eastern Saskatchewan and conducting a 15-corehole drilling program to determine stratigraphic correlation on both first and second white specks kerogen shale. In this program, correlation will be established between oil yield and oil quality, using different retort techniques, including modified Fischer Assay, steam retort and Rock-Eval. Results will lead to further resource evaluation and to a preliminary engineering design for a shale processing plant, including selection of retort process, upgrading of shale oil to petrochemical feedstock, hydrogen management, energy balance and evaluation of environmental impact.

May 1, 2002

By E. Uzun

"In this study, H2SO4 and HCl leaching behaviour of an ore sample containing 1.87% of Ni, obtained from the Karaçam (Eskisehir-Turkey) lateritic deposit that started operation recently was investigated. Acid concentration, temperature and reaction time were investigated as variables by comparative leaching tests and the optimum leaching conditions were selected on teh basis of Ni, Fe, Co and Mg behaviour. For H2SO4 leaching, optimum leach parameters were 95°C, a 12 normal H2SO4 concentration and 90 minutes of reaction time, and under these conditions Ni and Fe dissolutions were 97.6% and 95.4% respectively. On the other hand, 70°C, an 8 normal HCl concentration and a reaction time of 90 minutes were found to be the optimum parameters for HCl leaching, and Ni and Fe dissolutions found were 97.1% and 97.8%, respectively.INTRODUCTION Today, nickel and various nickel compounds are obtained from sulphide and lateritic nickel ores (Moskalyk & Alfantazi, 2002). Even though about 72% of the world's nickel reserves constitute lateritic ores, only about 42% of nickel is produced from these ores. The decrease in production from sulphide deposits, on the other hand, and increases in the use of nickel in the iron and steel, and battery production sectors, and especially the production of nickel cast irons in recent years, have accelerated the importance of making use of lateritic deposits (Luo et. al., 2010; Chang et. al., 2010). In the beneficiation of sulphide nickel ores, mostly pyrometallurgical methods are used. On the other hand, about 39% of lateritic ores are beneficiated by pyrometallurgical, and 61% are beneficiated by hydrometallurgical methods (USGS, 2009). In laterite beneficiation, the ore properties are of significance; that is to say, limonitic ores are eneficiated by high pressure acid leaching or via the Caron process, nontronitic ores are beneficiated by high pressure acid leaching or heat treatment (smelting), and ores containing serpentine by pyrometallurgical methods (Berezowsky, 2004; McDonald & Whittington, 2008a; Dreisinger et. al., 2015)."

Jan 1, 2017

By T. Adamcewicz

The province's lignite resources lie mainly in the south, extensions of the much larger deposits in Montana and North Dakota. Because of planned additional capacity, conventional steam power generation will probably remain as the dominant resource usage for many decades. Conversion of coal to other energy forms is receiving emphasis and in the future will compete with steam power generation in terms of quantities used.Economic deposits, minable by present-day technology, have been generally defined. Because a large percentage of the total lignite resource is in seams containing multiple partings, future extraction will become much more difficult and capital intensive.Increased public involvement will ensure that the impacts of future coal mining and usage operations are compatible with environmental and social objectives.

Jan 1, 1982

By Mario A. Morin

Over the years, several sources have stressed the need to better integrate the underground mine design and planning processes. The belief is that with better integration, better designs and plans will result - designs that are ?optimized?. Some researchers have focused their efforts on data integration, others have looked at closing the loop between production control & monitoring with mine planning & scheduling. In spite of all these efforts, fully integrated applications combining geological modeling, stope design and geomechanics, mine planning and scheduling, rock extraction and material handling system design, mine support systems, economic analysis with production control do not yet exist for the underground hard rock mining industry. There are several likely explanations - some economic, some technical. It is certain that the design and planning processes are interrelated and interdependent and thus are extremely complex to describe and understand. The mining engineer has an appreciation of the complexities involved - but how does he convey this knowledge to a programming team responsible for developing an integrated design & planning system. This paper will focus on software engineering methods, and other possible approaches, to describe and manage the complexities inherent in the underground mine design and planning process and the development of an integrated computerized system.

May 1, 2001

By K. Barbetti

"The carbon-in-pulp (CIP) process has been the dominant gold recovery process since the early 1980s. CIP has proven to be very adaptable for a wide range of ores and circuit configurations. The key performance indicator for CIP circuits is the minimisation of soluble gold losses to tailings, however, it is also important to operate the circuit efficiently (maximising gold loadings on carbon and minimising carbon inventory). Over the last 30 years the Curtin Gold Technology Group has studied CIP circuits as part of an on-going collaborative industry funded project (the AMIRA Gold Processing Technology Project). In the early years the project undertook basic research into understanding activated carbon, and its management in the circuit. More recently the development of process models and instrumentation has provided additional tools to assist operators. The results show that while most CIP circuits operate well, there are still significant opportunities for further cost savings, or additional revenue. This paper reviews the observations arising from this work, including key requirements for good carbon management, the results of benchmarking and industry surveys of carbon circuit over 20 years, the value of process modelling of CIP circuits to establish operating parameters, and the use of automated instrumentation to better optimise carbon control in the circuit.INTRODUCTION The introduction of activated carbon to recover gold from cyanide leach solutions in the last quarter of the 20th century was the most significant development in gold ore processing since the advent of cyanidation seventy years before. Replacing the Merrill–Crowe zinc cementation step with carbon-in-pulp (CIP) or carbon-in-leach (CIL) circuits provided a process that allowed the treatment of lower grade and problematic ores (e.g. high-clay ores), at lower capital and operating costs, and higher metal recoveries. The CIP circuit was first developed in the 1950s at the Carlton Mill, Cripple Creek, Colorado. All the components of the modern CIP process came to fruition at the Homestake Mine in South Dakota in 1973 (Fast, 1988). From the late 1970s onward a variation of CIP, carbon-in-leach (CIL) which combined the leach and adsorption stages, became the preferred circuit design in most parts of the word."

Jan 1, 2017

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 W. E. Roscoe

"Mineral exploration properties are those on which an economically viable mineral deposit has not yet been discovered. Such properties are bought, sold, optioned and joint ventured on the basis of their perceived potential for the existence and discovery of a viable mineral deposit. The intrinsic value of an exploration property is therefore based on the exploration potential. One measure of the exploration potential is the amount that can be justified to spend on exploration for a viable deposit.The appraised value method uses a cost approach to value exploration properties. It is based on the premise that an exploration property is worth the meaningful past exploration expenditures plus warranted future costs to test remaining exploration potential. Results of past exploration work are analyzed in order to retain only those past expenditures that are productive in terms of identifying remaining potential. Warranted future costs comprise a reasonable exploration budget to test that potential."

Jan 1, 2002

By R. Barbaroux, J. -M. Lalancette, D. Lemieux, K. Nasrallah, G. Garcia Curiel

"Arsenic released from the lithosphere by mining and metallurgical activities is a growing global environmental concern. Dundee sustainable technologies (“DST”) has developed a processing technology to sequester arsenic by means of vitrification. This method can effectively sequester arsenic trioxide without the need to oxidize from As (III) to As (V). Arsenic oxide is incorporated within a silica glass matrix that is stable as per the Toxicity Leaching Characteristic Procedure (“TCLP”) or EPA Method 1311. In this paper, the conventional treatment of arsenopyrite, commonly referred to as “two-stage roasting”, is discussed along with the options traditionally available for the remediation of the arsenic trioxide by-product. The drawbacks limiting the adoption of this processing flowsheet are discussed and a new processing route is presented for the treatment of arsenopyrite. This new flowsheet outputs an auriferous aluminosilicate highly amenable to gold extraction (> 96%) while eliminating the sulfur dioxide production associated with the second-stage roasting of pyrrhotite and ultimately uses vitrification as a definitive sequestration solution to arsenic trioxide.INTRODUCTION Faced with the depletion of conventional gold ores, the gold industry has witnessed a trend towards the exploitation of arsenical deposits. Arsenic is a naturally occurring metalloid often found in mineralogical association with gold. Many northern Canadian regions, from the Northwest Territories to Northern Manitoba, Northern Ontario and the Abitibi region are facing significant arsenic challenges. Projects are deemed uneconomic or prevented from going into operations due to the costs associated with handling arsenic material and there are penalties imposed to complex concentrates by smelters. In addition, Canadian mining operations have left an environmental legacy of gold tailings with grades typically of up to 9 grams per tonne with no processing solution as they also contain significant arsenic contamination at grades of up to 20%. Table 1 presents a list of Canadian deposits known to contain arsenic."

Jan 1, 2017

By R. K. Collings

The annual production of mineral and mineral-based wastes in Canada is conservatively estimated to be 400 million tons. Over 90 per cent of this amount is waste rock or mill tailings from the mining and mineral processing industry. The remainder are slags and ashes from the metallurgical industry, and sludges from the chemical industry. Because of impurity content, remote location, or both, most wastes have limited usefulness and, indeed, are a liability in that they must be transported to waste disposal sites and contained therein. Certain mineral wastes do, however, have potential value. Some contain small percentages of metals that may be economically recoverable with price increases; others consist of mineral material that may be used for such purposes as road base, construction aggregate, railroad ballast, and in the manufacture of bricks or blocks. Increased interest has been shown in mineral wastes in recent years. This paper reviews the types of mineral wastes available in Canada, briefly describes a number that have potential value, and notes possible uses and related research by CANMET and other organizations.

Jan 1, 1978

By P. Lafleur

All indications point to a growing market for thermal coal in Japan as part of the country's current energy policy formulation process. The Ministry of International Trade and Industry forecasts imports of 16 million tons a year in 1985 and 40 million tons in 1990-a twenty-fold and forty-fold increase over the present level. This potential reflects Japan's over-all serious and increasing concern for security of energy supplies and its resultant need to seek alternative sources. Nuclear power will be the main alternative source, but, because it is expected that its development will be slow, imported thermal coal will assume greater importance. Canada, with large resources of all types of coal, could fill a portion of this market. Thermal coal could come from specific thermal coal developments or from metallurgical coal mines, which usually produce a certain amount of coal not amenable to coking, but suitable for power purposes. However, penetration of this Japanese market by Canadian thermal coal will depend on the resolution of a number of problems. On the demand side, siting, environmental aspects, the need for a coal unloading and trans-shipment centre, and the added cost of installing coal-fired stations could be major constraints. Although Canada has ample high-quality resources, any new development tied to the Japanese market will require improvement in prices to cover the high costs associated with transportation, the construction of new mines and the provision of new infrastructure.

Jan 1, 1979

By Jas. E. Thomson

PUBLIC attention was first attracted to the Crow River area of north-western Ontario by the discovery of gold in 1928. The first three discoveries were eventually developed into Central Patricia, Pickle Crow, and Albany River mines. In 1929, preliminary developments were carried out at the Howell vein on N.A.M.E. (later Pickle Crow) claims, and in 1929 and 1930 surface and underground work indicated an ore-body at Central Patricia mine. However, due to the financial depression and the distance of these properties from the railway, it was not until 1934 and 1935 that, benefitted by the revaluation of gold, the real potentialities of these two properties began to be realized. Their immediate success led to a resumption of activity on neighbouring properties throughout the area in 1936 and 1937. Preliminary prospecting in the earlier period had been limited by the scarcity of rock exposures in the country. The procedure in the recent programme of intensive exploration has been along similar lines at most properties and has consisted lf detailed geological mapping accompanied by geophysical surveys and followed by systematic drilling of favourable zones. The present importance of the camp may be judged by the fact that, in 1937, Central Patricia and Pickle Crow mines together produced bullion valued at $3,662,953, and paid $1,450,000 in dividends. In addition, there were pro-mising gold developments at Albany River mine. During the past two seasons, the Geological Branch of the Ontario Department of Mines has been making a fairly detailed study of the geology and mineral deposits in the Crow River area. It is the purpose of this paper to present a brief statement of some of the structural features of these deposits; a summary of other geological information essential for the understanding of the main topic is included. A more detailed report on the area will be published shortly by the Ontario Department of Mines. It is impossible to make full acknowledgment here for all help received, for the writer is in-debted to the management, staff, and consultants of every Company in the camp for generous co-operation in the field and for information, plans, maps, and records placed at his disposal. Reports and articles on properties in the area have been written by Hurst (1), Cormie (2), Reid (3), and the staff of Pickle Crow Gold Mines ( 4).

Jan 1, 1938

By J. O. Marsden

Over the past eight years, Phelps Dodge (a division of Freeport-McMoRan Copper and Gold, Inc.) has developed a suite of proprietary hydrometallurgical processes for the treatment of copper concentrates as an alternative to conventional smelting and refining technology. The technical viability of two processes has been commercially demonstrated in a large scale plant at Bagdad, Arizona, designed to process approximately 52,500 metric tons per year of concentrate containing 30.5% copper. The first process utilizes high temperature (225°C) pressure leaching, followed by countercurrent solid-liquid separation, and then blending of the copper-bearing solution with low grade stockpile leach solution for subsequent treatment by SXlEW for copper recovery. The second process uses super-fine grinding, medium temperature (l60°C) pressure leaching, followed by solid-liquid separation, and treatment of high grade copper-bearing solution by direct electrowinning to recover the bulk of the copper values. The latter process will be utilized at Morenci in a commercial facility designed to treat mixed chalcopyrite-chalcocite-covellite concentrates. This facility is scheduled to start up in 2007. Other flowsheet options have been developed by Phelps Dodge for application to a variety of concentrate materials in specific situations. Examples of various flow sheet options are presented in this paper, and the advantages and disadvantages associated with each are discussed in detail.

Jan 1, 2007

By A. J. Hyett, R. D. Reichert

"A laboratory and field research program was conducted to investigate the major factors influencing bond capacity of grouted cable bolts. The results indicate that cable bolt capacity most critically depends on the grout uniaxial compressive strength (UCS), the radial confinement, and the embedment length.In the laboratory &apos;split-pipe&apos; tests were conducted using P VC, aluminum and steel pipes to provide radial confinement, and field test sites were chosen in granite, limestone and shale rock masses. For both datasets higher capacities were obtained under conditions of higher radial confinement. A correlation between the two was obtained through a comparison of the radial wall stiffness of the laboratory pipes with that of the field boreholes as measured using a high pressure dilatometer. Cable bolt capacity was found to increase with embedment length though not in direct proportionality.The use of low water cement ratio grouts (<0.40) can increase cable bolt capacities by 50% to 75%. This effect is maximized under conditions of high radial confinement. However, the use of super thick grout paste (0.30 and less) may be both impractical and undesirable, first because of their limited pumpability and second because of their inconsistency in strength. Grouts with a water cement ratio of between 0.35 and 0.40 are recommended for practical cable bolt applications."

Jan 1, 1992

By Habib Zughbi, Paul Zulli

"A key step towards sustainability in iron and steelmaking is to optimise the use of raw materials and energy consumption, and consequently minimise CO2 emissions. Models based on a Process Integration (PI) approach play a key role in evaluating various scenarios and the impact of introducing changes in raw materials and operational conditions on the overall energy consumption and CO2 emissions. BlueScope uses a PI based comprehensive model for its Port Kembla Steelworks (PKSW), called the Integrated Steelworks Energy and Emissions Model (ISEEM). ISEEM is tightly coupled to the configuration of PKSW. It is based on mass and energy balances as well as thermodynamic relationships. ISEEM is a steady-state model and is used to predict overall and detailed unit-by-unit energy consumptions and CO2 emissions. It is also used for plant-based scenario modelling. This paper investigates the impact of major changes to PKSW configuration, including the shutting down of a blast furnace and cokemaking battery, on the energy consumption and CO2 emissions of the plant. It discusses some of the issues involved in updating the model and some identified opportunities."

Jan 1, 2015

By J. I. Carroll, J. A. Walker

"Abstract - Camelback is a small (=200 000 tonnes), moderate grade (5%-7% Zn+Pb), volcanogenic massive sulfide deposit, which occurs within the Nepisiguit Falls Formation of the Ordovician Tetagouche Group. The host rocks are tuffaceous sedimentary rocks (Little Falls member) that overlie quartz-feldspar porphyritic tufflavas (Grand Falls member). The hanging-wall sequence comprises rhyolite of the Flat Landing Brook Formation, overlain by the Forty Mile Brook tholeiitic basalt. A dike of unaltered andesite was intersected beneath the massive sulfides, but was not found in the hanging-wall sequence in the vicinity of the deposit. The stratiform part of the deposit is made up of two, steeply south dipping, subparallel massive lenses that average approximately 4 m in thickness. Each lens is zoned, with an upper part consisting mainly of a pyrite and a basal part containing pyrite, sphalerite, and galena, with Ag values. The Au content in the massive sulfides is low (average = 52 ppb for 271 samples), but tends to be enriched in the massive pyrite near the top of each lens. Oxide facies iron formation is spatially associated with the massive sulfides, and has been traced up to 1800 m along strike. Footwall hydrothermal alteration is typical of VMS systems, and is characterized by depletion in K2O and Na2O, and enrichment in MgO and Fe2O3T with proximity to massive sulfides. The massive lenses are underlain by intensely chloritic, fine-grained, tuffaceous sedimentary rocks containing locally significant sulfide (chalcopyrite > pyrite > pyrrhotite) veins, which are interpreted to represent feeder zone mineralization. Unlike many VMS deposits, there is no evidence of silicification beneath the massive sulfides at the top of the feeder zone. The oxygen isotopic compositions (d18O = -1.5‰ to -0.3‰) of hydrothermal chlorite coupled with sulfur isotopic compositions (d34S ˜ 12‰) of the massive sulfides suggest that seawater was the dominant fluid in the hydrothermal system. Normalized rare earth element diagrams show flat Ce profiles and positive Eu anomalies, indicating that modified seawater was involved in ore formation; i.e., high-temperature (=350ºC), acidic, and reduced prior to entrainment into the hydrothermal cell. Although, seawater was the dominant fluid in the sulfide-forming system, d34S values of stringer zone sulfides (8.5‰) coupled with elevated Sn (400 ppm) in one massive sulfide sample indicate that there was at least some magmatic component in the hydrothermal cell."

Jan 1, 2006

By L. M. Dwarkin, D. F. Coates

Crows Nest Industries Limited adopted roof bolting in 1963 to improve roof control and to extend continuous miner utilization in one mine. Bolting was held back because anchorage tests gave inconsistent results. The time lapse between mining and bolting was suspected as a cause, and so a test entry was driven and sections of it were bolted as part of the work cycle in addition to the normal timbering. This paper presents the results of the instrumentation of test entries and discusses the utilization of the data to improve mining procedure.

Jan 1, 1967

By N. T. Avard

THE profitable disposal and utilization of much of our slack coal, lignite, and other low-grade fuels is one of the major problems facing the coal mining industry of Canada today. It is my belief that the pulverization process applied to these fuels opens the door to greater efficiency and greater prosperity, and I wish to discuss briefly with you some features of its development and advantages to date. Indeed, the art of burning pulverized coal under stationary boilers is one of the romances of modern engineering. As a Nova Scotian, I feel some pride in the fact that at Chignecto Mines, N.S., was built in 1906 the first pit-mouth power plant on the North American continent. This was built to make effective for the first time Edison&apos;s dream of carrying coal for power by wire rather than by rail. This plant, built by the Maritime Coal, Railway and Power Company, Limited, success-fully utilized underfeed stokers for twenty years but in 1927 was replaced by a more modern plant equipped with machinery for burning pulverized coal, which is now operating very successfully. A further source of pride is the fact that the first boilers on this continent to be operated by pulverized coal were installed by the Dominion Coal Company at New Waterford, N.S., in 1912 and were satisfactorily operated during the lifetime of the plant. It is an acknowledged fact that average living conditions on a large part of the North American continent are far superior to those of any other people on earth. The reason is that we use so much more machinery per capita, and cheap power supply has been a large factor in bringing that about. Statistics show that where one horse-power was used one hundred years ago to assist man in his work, five hundred horse-power is used today. Truly a remarkable development and the key to our present high standard of living. Lack of coal in the chief industrial centres of Canada has forced the extra-ordinary development of the water powers which Providence has placed in those centres. How many of us realize that Canada stands second in the world in the per capita development of hydro power, Switzerland being first and the United States sixth? From this condition, we are reminded of the fact that the per capita foreign trade of Canada far exceeds that of our great neighbour to the South-but another illustration of the benefits accruing from our great power development.

Jan 1, 1937