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By D. F. Sherwin

"THE AREA which is described in this paper (Fig. 1) includes the continental margin of eastern Canada extending from the Gulf of Maine to the north edge of the Grand Banks, which, including the continental shelf, slope and rise, comprises an area of about 600,000 square miles. The paper is intended to give a background of the geological setting of this region in the context of its ultimate potential for oil and gas reserves in close proximity to the Nova Scotia energy market.HISTORY OF EXPLORATIONThe history of geological exploration of this area really began in 1878, when U.S. fishing boats brought back samples of rock recovered in trawls from their expeditions to the long-famous fishing banks off Canada's East Coast. Tertiary and Cretaceous fossils recovered from these samples indicated that the eastern Canadian continental shelf was actually the submerged northern extension of the Atlantic Coastal Plain."

Jan 1, 1972

By S. W. Marcuson, P. J. Mackey

The Canadian non-ferrous mining and metallurgical industry has made great strides in environmental protection during the past half century. The path taken by the copper-nickel smelting industry in reaching today’s level is traced in this paper. Following the practice at early copper smelters in Wales and in the US, Canadian smelters originally used tall stacks to disperse furnace of-gases. This was the normal mode of operation and was accepted by society and by Government. Gradually, Government regulations required fixation of sulphur dioxide emissions and Canadian companies responded with significant technical developments to achieve this result. The initial development in Canada of the first new technologies such as the Cominco Flash Suspension Roaster and the Freeman Flash Smelting Process - both representing early versions of the modern established flash smelting technologies - and then later technologies such as the Inco Flash Smelting Process and the Noranda Process, both of which continue to this day, are discussed in this paper in terms of their contributions to the development of environmentally friendly plants. The evolution of these and other technologies is also discussed. Some comments regarding how the industry will face the future are also included.

Jan 1, 2015

By Guoxiang Chi

Hydrocarbon fluid inclusions entrapped in diagenetic minerals may be used to constrain hydrocarbon exploration models in two aspects. First, the distribution of different types of hydrocarbon inclusions in different tectonostratigraphic domains, and their relationships with organic matter maturation levels may reflect a regionalscale variation in the thermal regimes of the hydrocarbon systems. Second, the relative timing of hydrocarbon inclusions in the diagenetic history may provide constraints on the evaluation of reservoir potential. This paper summarizes the distribution of hydrocarbon inclusions in four different Paleozoic tectonostratigraphic domains in eastern Canada, discusses its implications on hydrocarbon systems in the different domains, and finally provides two examples to show how the relative timing of hydrocarbon inclusions may be used in the evaluation of reservoir potential. Oil inclusions mainly occur in host rocks that are within the oil zone, although some are found in units in the condensate zone. Light hydrocarbon inclusions occur in the dry gas zone, and methane inclusions were found from dry gas zone to anchimetamorphism zone. This correlation between hydrocarbon inclusions and host rock maturation implies that the hydrocarbons were derived from source rocks having a maturation level broadly similar to the host rocks. Although the Paleozoic rocks are generally relatively poor in reservoir quality, the two examples provided in this paper show that in some stratigraphic units, significant secondary porosities could have existed prior to some hydrocarbon migration events, thus favoring the accumulation of hydrocarbons.

May 1, 2001

By N. Molaei, E. R. Bobicki

The continued demand for mineral products, coupled with the depletion of high-grade ore resources, has led to the mining of lower grade ores, which often require fine grinding to achieve mineral liberation. Regrinding of low-grade ores results in the production of fine gangue mineral solids and produces vast quantities of fluid fine tailings which are difficult to separate from water, particularly if they are composed of clay minerals. Organic synthetic polymers and inorganic salts have been widely applied in flocculation of colloidal suspensions in the treatment of mining tailings. However, there are growing concerns regarding their impact on the environment and human health. Recently, extracellular biopolymer flocculants or bioflocculants have attracted much attention as alternative reagents. In this study, much effort has been devoted to considering the effectiveness of protein and polysaccharide-based biopolymers for the dewatering of clay slurries. The interaction between kaolinite and illite clays and biopolymers was investigated via settling tests at pH 7 and 10. Zeta potential measurements were also conducted as a complementary technique. Results showed that protamine and lysozyme protein- based biopolymers were generally the more effective bioflocculants. Pectin, a polysaccharide-based biopolymer, showed a dispersing effect and has the potential to be used as a dispersant and/or depressant for clay minerals in froth flotation. INTRODUCTION With the depletion of high-grade ore resources, the need for mining of low-grade ores has increased over the past few decades (Bourgès-Gastaud, Stoltz, Dolez, Blond, & Touze-Foltz, 2014; Chen, Walshe, Fru, Ciborowski, & Weisener, 2013; C. Wang, Harbottle, Liu, & Xu, 2014). Low-grade ores often require fine grinding and contain clay minerals, leading to the generation of fluid fine tailings (FFT). It is a challenging process to separate suspended clay particles from water (Craciun, Manaila, & Stelescu, 2013; Dompierre, Lindsay, Cruz-Hernández, & Halferdahl, 2016; Kasperski & Mikula, 2011; Mercier et al., 2012). Clay minerals form stable dispersions in water due to their anisotropic nature, non-spherical morphology and colloidal size (Lagaly & Ziesmer, 2003; Olphen, 1977). The difficulty in separating clay minerals from water has led to the accumulation of vast quantities of FFT in oil sands, phosphate, copper and nickel operations, representing a huge liability for mining companies (Chen et al., 2013; Mercier et al., 2012)

Jan 1, 2019

By J. A. Brusset

Introduction I am indebted for most of the information in this paper to Mr. P. S. Lea, Deputy Chief Inspector of Mines of Great Britain, and Mr. A. E. Crook, Engineering Inspector of Mines, Ministry of Fuel and Power. Other coal-mining men in Canada may be as surprised as I was to learn that there are twenty-five Diesel locomotives in service underground in British gassy coal mines. Many more are in use underground in non-gassy coal mines and in metal mines. Approval has been granted for an additional fifty flame-proof locomotives to be used in gassy mines, and these should be in operation by the end of 1946, or as soon as manufacturing facilities permit.

Jan 1, 1946

By ManhKha Trinh, Neal Pyke

Dofasco was the first company to adopt oxygen steelmaking in North America in 1954, two years after the first LD vessel installed and operated successfully in Linz, Austria. Since then, Dofasco has investigated and implemented several strategies to maximize hot metal usage and minimize overall cost. Some key strategies -low hot metal silicon, combined blowing conversion, vacuum degassing tank upgrade and BOF slag carryover control - are discussed. Post combustion, scrap preheat, carbon injection trials along with current operating philosophies are described.

Jan 1, 2004

By N. Aslin, R. Clark, G. Heferen

The methods of harvesting copper from stainless steel mother plates has been investigated from fundamental and operational experience perspectives. At least five different harvesting techniques have been identified that have different effects on product quality, current efficiency, current distribution, growth morphology and ease of stripping. Each method is examined from fundamental principles to understand what occurs during the harvesting process and why the particular effects are manifested. Experience from plants operating the harvesting method is provided to show that the fundamental understanding is relevant. Best practice harvesting method and harvesting management are described.

Jan 1, 2014

By T. Yalcin

"This paper describes a process that can provide high rates of dewatering and that has the potential of bringing significant savings in tailing disposal costs. It involves a three-stage, closed-circuit operation employing a hydrocyclone, a settling cone and a thickener. The mill tailing, with adjusted pulp density, is first fed to the hydrocyclone. The underflow from the hydrocyclone goes to the settling cone for further dewatering. The overflows from the hydrocyclone and the settling cone are sent to a thickener which, with the addition of a flocculant, gives a clear liquid effluent and a dilute underflow which is recycled back to the hydrocyclone. The underflow of the settling cone is a material with as high as 78% pulp density and is suitable for direct disposal or for use as mine backfill.INTRODUCTIONDewatering is an essential process for the disposal of mill tailings and forms an additional cost item in milling operations. Cost-cutting measures are therefore desirable in this area as in any other stage of milling. One way of achieving this is through increased rate of dewatering which would require smaller dewatering units with correspondingly lower capital and operating costs."

Jan 1, 1987

By R. Thierbach, W. Kahnt, Oberthür. T., D. Eisenburger, V. Gundelach

ABSTRACT: The ground penetrating radar (GPR) method was used in a platinum mine in Zimbabwe by members of the Federal Institute for Geosciences and Mineral Resources (BGR). The measurements were carried out in boreholes and drifts. Electromagnetic re?ections from a fault that consistently trends parallel to the mineralization zone permitted the mapping of the economically minable parts of the deposit. An introduction is given to the geology of the studied area and the application of the GPR method. The electrical parametres of the rocks are measured in situ, the GPR measurements are displayed with radargrams, and the visible structures are explained in illustrations.

Jan 1, 2010

By Robin Phinney

Certain statements in this presentation may constitute "forward-looking" statements which involve known and unknown risks, uncertainties and other factors which may cause the actual results, pe1formance or achievements of the Corporation, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. When used in this presentation, such statements use such words as "may", "would", "could", "will", "intend", "expect", "believe", "plan", "anticipate", "estimate" and other similar terminology. These statements reflect the Corporation's current expectations regarding future events and operating performance and speak only as of the date of this presentation. Forward-looking statements involve significant risks and uncertainties, should not be read as guarantees of future performance or results, and will not necessa1ily be accurate indications of whether or not such results will be achieved. A number of factors could cause actual results to differ materially from the results discussed in the forward looking statements including, but not limited to, the factors discussed in the Corporation's annual information form filed on March 9, 2011. Actual results could differ materially from those currently anticipated due to a number of factors and risks. These include, but are not limited to, the failure to obtain necessary regulatory approvals, including environmental approval, the failure to secure full project financing, the failure to implement the recommendations set out in the Technical Report, the failure to raise financing to implement the recommendations in the Technical Report, risks associated with the mining industry in general (e.g., operational risks in development, exploration and production; delays or changes in plans with respect to exploration or development projects or capital expenditures; the uncertainty of estimates and projections relating to production, reserves and resources, costs and expenses; and health, safety and environmental risks), decrease in potash prices and exchange rate fluctuations. Although the forward-looking statements contained in this presentation are based upon what management of the Corporation believes are reasonable assumptions, the Corporation cannot assure shareholders that actual results will be consistent with these fonvard-looking statements. These fon\?ard-looking statements are made as of the date of this presentation and are expressly qualified in their entirety by this cautionary statement. Subject to applicable securities laws, the Corporation assumes no obligation to update or revise them to reflect new events or circumstances. This presentation is a market update based on the Corporation's public disclosure and does not form a part of any offer of securities, or constitute a solicitation of any offer to purchase or subscribe for securities. Any purchase of securities in the company should be made solely on the basis of information contained in the Corporation's public record which is available on www.sedar.com .

May 1, 2013

By I. Caraconcea, M. Cousineau, S. Gariepy

"Several base metal plants operate in low grade/high tonnage conditions which impose strict cost control on all fronts for their operations to remain profitable. This leads to decisions regarding plant design, procurement, operations and maintenance that often favor cost minimization over value optimization. This may hinder the representativeness of the metal accounting systems while this should be a priority in a low margin environment. Such poor representativeness not only creates confusion in plant scheduling but can also hide suboptimal metallurgical performance. Furthermore, this situation can run undetected for a while since one dominant feature of a poor metal accounting system is its poor self-awareness. During their practice, authors have particularly identified measurement bias and reproducibility, as well as their impact on metal recoveries as areas of concern. These issues have not been extensively reviewed in the specific context of precious metals in base metal plants. Pragmatic solutions are proposed either at the design stage for a new project or to retrofit an actual operation. These solutions should be based on a business analysis that set a value of information matching the contribution of precious metals as well as the potential to use such information to act toward increasing plant profitability. Conclusions are that trade-offs are an inherent part of the design/audit/retrofit of any metal accounting system in any plant processing either base or precious metals. However, compromises must be evaluated on economic/technical ground.INTRODUCTION Every mineral processing plant must produce metal accounting reports (Morrison, 2008) where estimated saleable metal flows and inventories are published. These metal accounting reports are delivered to a variety of stakeholders who use them for internal management purposes (day-to-day plant production planning, plant operation optimization, capital spending, etc.) as well as for external management (royalty settlements, tolling agreements, etc.). Hence, there should be no doubt that state of the art metal accounting is instrumental for mining companies to reach and sustain high-quality corporate governance (Gaylard, Randolph, & Wortley, 2014). However, producing a metal accounting report involves much more than just printing it (Lachance, Leroux, & Gariépy, 2015a). The underlying metal accounting system (Figure 1) is responsible not only for the reliable production of the metal accounting reports but also for the quality of the outcome. As such, the crucial tasks of its design/audit/retrofit should neither be seen as ancillary nor be left as an afterthought."

Jan 1, 2017

By Patrick Rennkamp, Wolf-Dieter Trodel, Andy Fearn

"The Jansen shafts are completed using purely mechanical excavation. This paper summarises the geology, a description of the shafts, the method used for excavation and the results achieved along with the challenges encountered and the solutions developed during the project. This experience is now being applied in the next generation machines and shaft sinking processes. This pioneering approach is changing shaft sinking in soft and medium to hard rock. INTRODUCTION The Jansen Mining project located approximately 150 km east of the city Saskatoon is the location of the BHP owned potash mine with an expected mining output of eight million tonnes annually upon completion. Mining contractors DMC Mining Services have used two Herrenknecht Shaft Boring Roadheaders (SBRs) to excavate the two blind shafts with an approximate excavation diameter of ten metres (inner diameter approximately 8.3 m) to depths of -975 and -1005 metres, respectively. The SBRs excavate the rock by a partial-face cutting method, using a transverse cutting drum mounted on a telescopic boom. The excavated rock is then conveyed away from the bench by an innovative pneumatic system and transferred into muck buckets to be hoisted to the surface. No drilling and blasting was done to keep to the BHP philosophy of using only mechanical excavation for this reference project. BHP VISION – MECHANICAL EXCAVATION BHP focused on mechanical excavation at Jansen due to the following perceived benefits: 1.No workers in the excavation chamber (shaft bottom), minimizing the exposure to traditional shaftsinking hazards associated with working in the shaft bottom. 2. Minimal damage to the rock fabric reducing the need for ground support and avoiding potential impact damage to freeze tubes located around the shaft. 3. Accurate excavation diameters with no overbreak, reducing volumes of rock to be removed and replaced with concrete lining."

Jan 1, 2019

By A. Gutiérrez

At present, most ore milling is done in tumbling mills, consisting of huge cylinders turning on their horizontal axis. This rotational motion causes the ore charge and the grinding balls to interact by impact, compression and abrasion, to reduce the size of the ore. This method is very inefficient since only around 12% of the energy supplied is used for actual grinding, the rest being used in moving the large mass of balls and ore within the mill. This work aimed at better understanding the milling process by evaluating the movement of the load through the Discrete Elements Method (DEM). First, the number of bodies (balls and ore) moving inside the mill is determined, to correlate to the potential impacts that constitute one of the milling mechanisms. Then, the number of high energy impacts is evaluated to correlate to the bodies in motion. At this stage, a differentiation between grinding media and the ore, as well as between the types of contact taking place in the mill, has to be made. This latter issue is of great relevance since from the five identified contact types (ball-ball, ball-liner, ore-ore, ball-ore and ore-liner) only the last three actually contribute to the milling process, the other two causing structural damage to the mill.

Jan 1, 2007

By R. D. White

"The Cumberland Basin of Nova Scotia has long been considered a structural basin by virtue of the elliptical outcrop and inward dip pattern of the Pennsylvanian outcrops. Recent published and unpublished data indicate that subsidence began in the late Devonian, perhaps resulting from a graben or rift. The Mississippian sediments which filled the growing depression were continental, lacustrine and marine with evaporites. The cessation of the riftforming processes is recorded by the alluvial swamp-type sediments of the Pennsylvanian which filled the depression. In excess of 25,000 feet of Carboniferous rocks are believed to be present in the deepest part of the Basin. Starting with the rift hypothesis, we can speculate on the kinds of sediments, their location and the structural features present beneath the Pennsylvanian surface. Using surface exposures and a limited amount of subsurface data, we theorize that (1) the Mississippian evaporites acted as glide zones which effectively divided the Basin into two horizontal structural layers. The rocks above the evaporites, responding to Appalachian stresses, formed the long diapiric folds with cores of overthickened evaporites. Below the evaporites the structures are related to movements of the rift floor, compaction closures and structures formed by differential horizontal movements of the rift walls. (2) The rift, in its deeper parts, will have more and a greater variety of marine rocks than the outcrops indicate. Should the rift hypothesis be correct, the possibility of finding hydrocarbons is enhanced."

Jan 1, 1972

By B P. Scott

Podsol soil horizons developed on Pleistocene glacial sediments overlying the Coronation Mine orebody were analyzed for copper and zinc spectro-photometrically, using biquinoline-isoamyl alcohol and dithizone carbon tetrachloride reagents. Copper and zinc are concentrated in the A. and C horizons, whereas the A1, A2 and B horizons are leached. Of economic significance is the fact that the C horizon contains a copper anomaly, in excess of 100 times back-ground, directly over the orebody. Due to the erratic distribution of high copper concentrations in the Ao horizon with respect to the orebody, that horizon is not considered as a reliable prospecting datum. U NDER certain conditions, metallic ore deposits are accompanied by primary halos of trace elements in unweathered rock surrounding the orebodies or by secondary halos in weathered rock, alluvium, soil, or vegetation above or near the mineralized zones. Where such halos occur, chemical analysis, as applied to the detection of trace elements, is a valuable prospecting aid, permitting the detection of mineralization of possible economic value.

Jan 1, 1965

By J. S. Godard

The mining developments in western Quebec have shown the ores of this district to be more complex in character than was at first expected. When the initial discoveries were made it was thought that the ores would be similar in character to those of Kirkland Lake and Porcupine areas. Developments have since shown that although the ores along the southern margin of the belt are somewhat similar, those within the belt, constituting by far the greater proportion, are vastly different, being complex mixtures of base-metal sulphides carrying values in the precious metals. These mixtures of base-metal sulphides of copper, zinc, and iron, present several problems to the metallurgist, especially in their concentration into marketable products. For the purpose .of this paper the following classification may be made of the ores of the district. Group I. - Milling Ores: (a) Ores in which~ arsenopyrite is the predominating sulphide. In this class of ore the gold occurs in fractures in the quartz and is associated to a lesser extent with the arsenopyrite and pyrite. Examples of this class of ore are the Granada, south of Pelletier lake, and the O'Brien and the Thompson in Cadillac township. (b) Ores in which iron pyrite is the predominating sulphide and gold is the valuable constituent. This may also be classed as a concentrating ore-Group III.

Jan 1, 1928

By N. Morrison, I. Holl, R. Welyhorsky, A. Hempstock

ABSTRACT: The Victor diamond mine is located in the James Bay lowlands, 90 km west of the First Nations village of Attawapiskat. The project was the first of its kind in northern Ontario. The process plant was designed to produce a 95 to 98% by weight diamond concentrate through three stages of comminution, dense medium separation, and proprietary X-ray technology for final recovery. The plant was commissioned over a period of six months, commencing prior to substantial completion of construction. Through effective planning of the commissioning phase, the Victor mine start-up was safely completed nine months ahead of schedule.

Jan 1, 2011

By J. E. Hawley

"The property of Francoeur Gold Mines, Limited, lies directly west of the Armfield mine in Beauchastel township, Abitibi district, and 12 miles west and slightly south of Noranda. The gold deposits are of particular interest because of their replacement character and close association with fault zones. The property was originally staked in 1923 following the discovery oi a mineralized zone near the eastern boundary. This became No. 1 orebody. Later discoveries in 1936 of No. 2 and No. 3 orebodies led to underground development and actual mining in July, 1938. A fourth orebody, No. 8, was found in 1939.The following is the production record up to December 31st, 1947:Beginning in September, 1944, ore was shipped to Noranda as siliceous flux, but late in 1946 milling of low-silica ore from No. 1 orebody was undertaken until operations were temporarily suspended in 1947.The four main ore deposits, Nos. 1, 2, 3, and 8, consist of siliceous ferrocarbonate and albite replacement bodies mineralized with fine pyrite and specularite in schistose fault zones in Keewatin volcanics. Barren to low grade quartz veins though present in some are uncommon, but small stringers of quartz are usually present wherever here and there visible gold is found. Nos. 1, 2, and 3 deposits lie in a major fault zone that extends completely across the property from west to east (over 7,000 feet) and dips N.40° to 50°, and are separated by intervals of 1,800 to 2,000 feet respectively. The fourth lies in a smaller fault zone striking east and dipping on the average 65°S.No. 1 orebody has been explored by mining to a depth of 500 feet, No. 2 to 400 feet, and No. 3 to slightly less than 300 feet . The greater part of No. 8 lies above a depth of 200 feet, but a raise has recently .been driven through from the west end of the 5th level of No. 1 to the 2nd level on No. 8 zone. Most of the ore of No. 8 zone above the 2nd level and of Nos. 2 and 3 above the 3rd levels has been removed."

Jan 1, 1954

This paper outlines the position and capabilities of Western Canada's bituminous coal industry, and indicates the increasing importance of Japan as an export market. The use of coal in Japan is reviewed, especially as regards future trends, and an appraisal is made of Canadian coal in comparison with domestic Japanese coal and imports from other countries. The importance of maintaining a solid nucleous within the Canadian bituminous coal industry is emphasized. I N RECENT years, Japan has emerged as a valuable market for Canadian exports. The first major product exported in volume to Japan was wheat, which has become very successfully established in Japanese markets. Following this, iron ore gradually found a market in Japan, with exports usually based on long-term contracts. This iron ore was produced entirely in British Columbia In 1958, the Western Canadian bituminous coal industry -jointly with the Dominion Coal Board -sent an official mission to Japan to investigate the

Jan 1, 1964

By V. Sheikhzadeh, M. Saghaeian, R. Hejazi, P. Ghobadi

Design and selection of equipment for a grinding circuit strongly depends on the mill function, ore properties and requirements of the down-stream circuit. Primary mills usually work in open circuit and size distribution of product would be controlled in the final steps using a classifier like cyclone. Although HPGRs are mostly utilized as pre-grinding mills, it is preferred to utilize them in a closed circuit due to their specific mechanism of comminution. Unique mechanical design of HPGR and its completely different crushing process than tumbling mills needs precise consideration on its circuit design. In this paper, we investigate the impact of different parameters on design of pre-grinding HPGR circuit and selection of the proper classifier. Our study focuses on iron ore properties (e.g. moisture, particle size distribution of feed and product, compatibility and de-agglomerability). We also investigated various options of HPGR circuit according the classifier efficiency and influences on down-stream processes. The optimum operating parameters of HPGR (working pressure, speed and level of hopper) for the selected circuit were also determined based on pilot and industrial data. Our pilot and industrial tests and observations revealed that HPGR should be arranged in closed circuit because of the edge effect, as a negative factor of non-uniform distribution of pressure force along the roller width and presence of non-crushed particles in the mill product. Wet vibratory screen could be the optimum option for screening of its discharge. Fine part of the wet screen discharge could be delivered to the concentration stage without over-grinding in ball mill using a hydrocyclone working in a reverse closed circuit mode. Moreover, our pilot and industrial tests during design and operation of ten HPGRs in various iron ore processing plants proved that higher pressure and lower roller speed in a fixed level of material inside the hopper could give the desired product size distribution.

Jan 1, 2016