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By R. P. Viljoen, A. D. Scheglov, A. L. Sokolov

"Abstract -The distribution of mineralized provinces is analyzed on the basis of their genetic link with specific blocks of the earth's crust including ancient platforms, mobile belts and zones of tectonic­ magmatic activation. Mobile and fold belts surround the Siberian platform in Russia and the Kaapvaal craton in South Africa, with decreasing age zoning away from ancient platform margins. The main differences in the geological development of the two cratonic areas are: (1) the long period before the final stabilization of the Siberian platform (3600 Ma to 1600 Ma) and the comparatively short period of time for the stabilization of the Kaapvaal craton (3600 Ma to 3050 Ma) and (2) the intensive multiple activation of the marginal zones of the Siberian platform and the tectonically­ controlled, magmatic sedimentary, intracratonic activity, typical of the Kaapvaal craton. Mineralization of the Siberian platform is largely characterized by marginal reactivation zones of differing ages although mineralized intracratonic Cu-bearing basins of Proterozoic age are also known. Mineralization of the Kaapvaal craton is mainly related to the formation of the intracratonic basins i.e., Witwatersrand (Au, U) and Transvaal (Au). The latter is characterized by multi-age volcanic-intrusive activity including the emplacement of Bushveld Complex (Cu, Ni, Pt, Cr, Au, V). The Siberian platform is characterized by the prolonged development of inherited mineralization from Archean until the late Mesozoic. The main period of mineralization in the Kaapvaal craton is restricted to the middle Proterozoic.The Baykal-Patomskaya and Namaqua-Natal mobile zones occupy similar positions adjacent to the Siberian and Kaapvaal cratons, respectively, and demonstrate similar modes of metallogenic development: i.e., the early formation of exhalative Pb-Zn-Cu deposits during the early stage and magmatic Cu deposits during the late stage. The more remote mobile belt near the Siberian plat­ form, the Trans-Baykal, is characterized by intensive multi-age mineralization (Wo, Mo, Sn, fluorite), related to a period of tectonic-magmatic activation. The Saldania Belt occupies a similar position near the Kaapvaal craton but is known for its poor Au, and Cu rnineralization. lt does, however, have some similarities with Trans-Baykal Belt in regard to Mo-W bearing granitoids.The phenomenon of interference of geosynclinal, orogenic, platform, and tectono-magmatic activation regimes is known for the Russian section of the Pacific Ocean Volcanic Belt."

Jan 1, 1994

By K. R. Nichol

The author points out that corrosion works 24 hours a day, every day. It is an economic reality that the cost of corrosion is inevitable and that its cost should be incurred in the least expensive way. An economic evaluation technique to properly assess its relative impact is the Discounted Cash Flow Method. Various remedial and corrosion control measures are available and these, when coupled with a planned corrosion control program, help reduce the cost of corrosion.

Jan 1, 1973

By J. J. Brummer

"A reconnaissance geochemical survey, using the stream sediment technique, is described. The survey covered an area of about 400 square miles, in the Seal Lake area of central Labrador, underlain by basaltic flows, diabase and metadiabase sills, and sedimentary rocks. Previous work had indicated numerous small copper occurrences within the Seal Lake group of rocks. Stream sediments were tested for the readily extractable copper content and total heavy metal content. The results of the copper survey did not yield any new data on the distribution of copper mineralization. Results of the total heavy metal survey attracted attention to a remote portion of the area (Ten Mile Lake), which had hitherto been regarded as having no economic interest. The anomalous values found, suggested that zinc mineralization should occur in this region. Geological mapping indicated that the rocks exposed belonged to the Letitia Lake Group, which is older than the Seal Lake Group exposed to the east, which contains the copper mineralization of the district.Investigation of the area lead to the discovery of: (1) uneconomic lead-zinc mineralization; (2) radioactivity extending over a considerable area. Evaluation of the radioactive rocks led to the discovery of columbium-thorium mineralization in amphibolite and in diopside-actinolite schists along a contact with intrusive alkali syenite.Thus a geochemical survey, which was planned to evaluate a copper province, resulted in the discovery of lead-zinc-columbium-thorium mineralization."

Jan 1, 1960

By Ming’an Wei, Qifu Duan, Jianmin Wu, Lusheng Zhou, HMR Group Limited / HMR Technology Canada Ltd., Wenjian Wu

"The development and industrial applications of magnetic liners have been around for decades. A Swedish company Skega first introduced rubber magnetic liners, and then followed by the Chinese invention of metal magnetic liners. Traditionally, both liners were used in secondary ball mills and regrind ball mills for industrial applications, especially for ores containing magnetic materials. Mostly steel balls or equivalent forged steel balls, usually below 60 mm in diameter, were used as grinding media. With the development of mineral resources over the years, SAG mills and larger ball mills have become the dominating components for comminution circuit design. Due to the development of larger diameter ball mills and thus larger ball charge diameter (up to 80mm) especially in non-ferrous metal mining operations, the application of magnetic liners have been very limited. Based on “Magnetism theory” and the development of new materials, the HMR Group Limited has been conducting researches on examining the structures of magnetic liners, associated materials and magnetic circuits which led to the invention of the Nano Alloy Steel Magnetic Liner (NSML). Recently, NSML had a successful application in a 5.5 m diameter × 6.5 m ball mill at the Erdenet Copper Mine in Mongolia. The NSML successfully handled a ball size up of to 80 mm, while achieving a service life of nearly 24 months, which is almost 3 times wear life of the original manganese steel liners.INTRODUCTIONDuring the development and utilization of mineral resources, mineral processing is an indispensably operation. The effective separation of various useful minerals depends on sufficient monomer dissociation of minerals in the ores. The crushing and grinding operation is prior operation of mineral processing. Ball mills are used in different concentrators. As the main consumption parts of mill, liners have been studied constantly. As a new kind of liners, magnetic liners besides can meet the requirement of production, and also have characteristics with maintenance-free, saving energy and increasing efficiency. So the magnetic liners are worth to be spread and applied world widely."

Jan 1, 2016

By B. Currie

Maintenance of quality electrowon copper requires an electrolyte which has suitable chemical and physical characteristics. The proper design and operation of the solvent extraction plant is essential to the quality of the electrolyte sent to electrowinning. An aspect that is not well appreciated is that the return electrolyte can have negative effects on the operation of the solvent extraction plant. Poor SX plant operation creates below optimum electrolyte conditions. High Eh in the return spent electrolyte can degrade the SX reagent with large decreases in copper transfer capacity and increases in internal entrainment. The synergistic interaction of the SX and EW plants needs a single-source design approach to address the interactions. The design elements in the SX and EW plants required to manage the electrolyte conditions are discussed.

Jan 1, 2014

By Pieter van Nierop

Outline ? What is gasification? ? Gasification Technologies ? Gasification ?The early years ? Gasification ? The last decade ? The Alberta Situation ? The Importance of Gasification in Alberta ? Polygeneration ? Development ? Conclusion

May 1, 2004

By G. O. Oniyide, H. Yilmaz.

"This paper presents the result of the research done on the effect of temperature on the dilatancy of rocks from the Bushveld Igneous Complex (BIC), where the South African Platinum mines are located. The BIC has higher virgin rock temperature (VRT) than the gold mines of the ‘Witwatersrand Basin Complex’. If the platinum mines advance to ultra-deep levels as the gold mines, since the Merensky Reef has been reported to extend beyond 5km, then the virgin rock temperature at 5 km below surface would be approximately 140oC. Hence, there is a need for the investigation of rock behaviour at high temperatures. Five different rock types (norite, leuconorite, mottled anorthosite, pyroxenite and chromitite) were tested in a 2600 kN servo-controlled multi-purpose triaxial testing machine. The tests were done at a constant strain rate of 5 x 10-1 S-1 and a confining pressure of 10 MPa within temperature range of 20 °C (ambient temperature) to 140 °C. The results show a general strength reduction and increasing dilation angles with increasing temperatures. The results also demonstrate that dilation angle is close to the internal friction angle at lower temperatures; however, they are greater at higher temperatures.INTRODUCTIONMany challenges are faced with increasing depth of mining in underground mines. The most obvious are heat, in-situ stresses and those associated with logistics. Issues related to underground heat have mainly focused on the side effect of heat on workers' health, increasing production costs as a result of higher cost of ventilation. The effect of increasing temperature with increasing depth on the behavior of rock has not been given much consideration. Generally, gold mines in South Africa are deeper than the platinum mines but the latter have higher temperature gradient, which makes the platinum mines to be warmer at similar mining depths. Although the study of the effect temperature on the behaviour of rock can be beneficial to both gold and platinum mines, the focus of the research is limited to the platinum mines because of their higher temperature gradient. Donoghue (2004) stated that the virgin rock temperatures (VRT) and air temperatures increase with depth, due to the geothermal gradient and auto-compression, that is, compression of air by its own weight."

Jan 1, 2015

By J. A. L. Henderson

THE potential oil-and gas-bearing area with "which this paper deals is the large undefined Carboniferous basin, roughly triangular in shape, occupying about 10,000 square miles of southern and eastern New Brunswick. Its base, about 135 miles long, lies on the gulf of St. Lawrence and embraces the whole eastern coast-line of the Province, while its apex lies in the south-west corner of the Province, near the International boundary (see map, Figure 1). The Carboniferous basin may be divided roughly into two areas-the Northern basin and the Southern basin-by a structural feature represented by a ridge of low hills running north-easterly from the Saint John river, near Saint John, on the southwest, to Indian mountain, about eight miles north of Moncton, in the northeast. Within the Northern basin, all evidence regarding the presence or attitude of the older Mississippian Albert Shale series, the only oil-bearing rocks known in New Brunswick, is for the greater part obscured by a thick and practically horizontal blanket of Pennsylvanian strata and, although evidences of oil and gas have been reported, none has been positively identified. Five parallellines of gentle folding, running to the northeast, occur in the Pennsylvanian rocks, within a distance of 100 miles from north to south. This folding is reflected in the courses of the rivers, which lie within the synclines. The relationship of the folding in the younger rocks to structures in the uncomfortably underlying older rocks is unknown, but should now be possible of clarification by means of a geophysical survey accompanied by drilling. Independent geological examinations have yielded no evidence of value in this respect, nor have five exploratory boreholes drilled by per-cussion tools to a maximum depth of 3,645 feet been of assistance, as only one inconclusive hole completely traversed the beds which normally overlie the Albert shales.

Jan 1, 1940

By Samuel O. Akande

"Gold occurs as native metal, in electrum, and in a telluride mineral in quartz carbonate veinlets of three vein systems at the Ross Mine, northern Ontario. The 14 Vein System is made up predominantly of concordant veinlets within layered ankeritic dolomite stratabound by, and conformable with, andesite tuff Individual veinlets contain pyrite, sphalerite, galena, chalcopyrite, tennantite, pearceite, proustite, native gold and electrum in a matrix of quartz, dolomite, ankerite and calcite. The 2B Vein System is made up of both concordant and discordant veinlets within andesite tuffs. The veinlets contain pyrite, chalcopyrite, sphalerite, bornite, tennantite and free gold in quartz, calcite and dolomite. The 18 Vein System is comprised of stockwork veinlets in and around intrusive syenite which has both sharp and gradational contacts with enclosing andesite tuff The veinlets contain pyrite, chalcopyrite, bornite, chalcocite, native gold and calaverite. Sulphide and silicate minerals in veinlets and wall rocks are stable assemblages for the regional metamorphism of greenschist rank. ,The 14 Vein System is interpreted as a metalliferous siliceous carbonate chemical sediment, the components of which were leached from the underlying volcanic rocks by convecting sea water and subsequently deposited on the sea floor between the extrusion of flows and pyroclastic rocks. Subsequent regional metamorphism and intrusions remobilized and redistributed the syngenetic stratabound material into dilatant fractures in adjacent tuff, as in the 2B and the 18 vein systems."

Jan 1, 1982

By F. Liu, H. A. Meier, D. M. Valiveti, P. A. Gordon

Hydraulic fracture is a frequently used technique in the Oil and Gas industry to create high permeability pathways for extraction of hydrocarbons. Numerical simulation of this method poses challenges such as representation of 3D fractures, propagation of randomly oriented fractures in 3D media, enabling fluid leak-off from fracture to poro-elastic medium. We have developed a numerical model using the Generalized Finite Element Method (GFEM) to simulate fluid driven fracture in a poro-elastic medium that addresses these challenges. In the GFEM framework, special enrichment functions are used to augment the solution space in the displacement and pore-pressure fields in order to accurately capture the response in the vicinity of the fracture. Adaptive refinement of the finite element mesh is also employed to facilitate accurate and efficient solution of the model. Our model fully couples fluid flow in the fracture, represented with the lubrication approximation, to the geo-mechanical behavior of the bulk poroelastic rock, comprised of an elastic rock skeleton saturated with fluid. Fracturing fluid exerts traction on the fracture surface and is also allowed to leak-off into the poroelastic medium using a transfer function approach. Stress intensity factors (SIFs) are evaluated based on the Contour Integral Method, accounting for the fluid pressure on the fracture surface. The SIFs are used to govern a full 3-D evolution of the fracture. Verification of the model is performed for known behaviors for the poroelastic response and fluid flow in the fracture.

Jan 1, 2015

By Robert A. Bosschart, Harold O. Seigel

"Most electromagnetic methods presently used in mining exploration are of the moving source type; i.e., the primary field source is moved simultaneously and in a fixed configuration with the receiver. Of the fixed-source methods, which employ a stationary primary field and a moving receiver, the Turam method is the most effective and has marked advantages over alternative electromagnetic methods. The results are little affected by topographic relief, and a high degree of resolution can be obtained because of the constant relation between source field and investigation area. Another inherent advantage of the Turam configuration is that it provides more favourable dimensional relations. Thus, the primary field attenuates at a much lower rate than in moving-source configurations and, secondly, the method is size sensitive; i.e., conductor size affects the strength of the response, which is not the case with moving-source methods. These factors result in a considerably better potential depth penetration."

Jan 1, 1966

By John Loui Porathur

Highwall Mining has been recently introduced in India. The first Continuous Highwall Mining extraction in India started operating at Ramagundem Opencast Project-II (OC-II) of Singareni Collieries Company Ltd. (SCCL) in December 2010. A new hybrid empirical and numerical modelling approach has been devised to design web pillars for the initial Highwall Mining sites in India, considering the complex geology, such as existence of thick seams and multiple seams in close proximity. This paper gives the scientific elucidation of a comprehensive design methodology adopted for the above mentioned Indian Highwall Mining sites. The design technology includes web pillar design for multiple seams using hybrid empirical and numerical methods, slope stability assessment, ground movement monitoring, and recommendations for conducting blasting operations in the vicinity of Highwall Mining extractions.

Aug 1, 2013

By Jian-bin Xie, Lin-fang Shen, Zhi-liang Wang

"In order to research temperature field for construction of connecting passage in Metro using artificial freezing method, the finite difference software FLAC3D is employed to numerically simulate construction process of connecting passage. During construction, the overall distribution of temperature field around connecting passage, the relationship between soil temperature and freezing time, the distribution and variation for the thickness of freezing wall are studied from the perspective of numerical analysis. The results show as follows: after 55 days’ freezing, the soil temperature surrounding connecting passage is about -24 oC ~ -28 oC, and the minimum thickness of freezing wall is about 4.0m, which is larger than the design value 3.1m. So construction conditions have satisfied to the excavation of connecting passage and pumping station. During the excavation of connecting passage, soil temperature has almost no obvious change and the thickness of freezing wall remains constant mainly. After 45 days’ normal thawing, the temperature of freezing wall rises 12 oC approximately. And the soil temperature rises faster at the beginning of the normal thawing stage. In the whole process of construction, the frozen area is about 5m outside the edge of connecting passage, and the cooling area is about 10m outside the edge of connecting passage. INTRODUCTIONThe first recorded application of the artificial freezing method is on a mineshaft project in 1862, and it has been widely used in foundation pit engineering, subway tunnels, mine shaft engineering and so on (Wang Zhiliang, 2010; Zhang Juanxia, 2012; Qiu Fan, 2007; Zhou Xiaomin, 1999). This method has many advantages of enhancing soil strength; decreasing permeability and adopting various unstable soils (silt clay, sand, gravel, etc.). It has been applied successfully in metro engineering construction in Beijing, Shanghai and Nanjing. According to incomplete statistics, the construction of connecting passage using artificial freezing method accounted for 98% in Shanghai metro (Qiu Fan, 2007)."

Jan 1, 2015

By Richard P. Taylor, Rod Henham

Abstract - Newly discovered pegmatites distributed throughout the sub-surface environs of the Musselwhite Archean gold deposit occur as narrow dikes that intrude most of the major lithological units. The mineralogy and textures of the pegmatite dikes are characteristic of granitic pegmatites of the "Rare-Element Class"; more specifically, they closely resemble varieties of the "Complex-type" granitic pegmatites that are commonly associated with zones of tantalum mineralization. The essential minerals in the dikes comprise albite, quartz, and K-feldspar, together with lesser amounts of mica (including lepidolite), spessartine, tourmaline, and locally, spodumene. Fine-grained (30 µm to 300 µm), tantalum-bearing minerals occur in the quartzo-feldspathic matrix of the dikes as disseminations, in interstices, and in small vugs. The nature of the tantalum-bearing mineral assemblage present in individual pegmatite dikes varies from a simple mineral assemblage composed of ferrocolumbite (with around 39 wt% Ta2O5) in the most northerly dike, to more complex assemblages comprised of manganotantalite (with up to 75 wt% Ta2O5), ferrotapiolite (with up to 79 wt% Ta2O5), and microlite (with up to 76 wt% Ta2O5) that are present in dikes located several kilometers to the south and southwest. The compositional characteristics and textural relationships of the tantalum-bearing minerals in the dikes provide evidence of igneous fractionation trends that are typical of rare-element granitic pegmatites. Such trends suggest that the newly discovered pegmatites represent part of a more extensive group of cogenetic, tantalum-mineralized dikes.

Jan 1, 2001

By L Gill

The four basic types of electric motors -squirrel-cage, wound rotor, synchronous and D.C. -are de-scribed, with particular reference to speed-torque characteristics. The three classifications of squirrel-cage motors, C.E.M.A. B, C and D, are compared, and methods of selection for specific drives are outlined. Wound rotor and synchronous motors are covered from the viewpoint of construction details, methods of operation and control required. The application of these motors to crushers, conveyors and ball mills is described and reasons for their selection are given. The application of D.C. motors to haulage equipment and mine hoist drives is included, and the basic principles of a variable voltage drive are illustrated. Efforts have been made through-out to provide specific examples of motor selection, with particular reference to the mining industry. THIS paper will attempt to answer the question -"which motor should be used for a specific drive?" Although it is impossible to cover the complete subject of electric motor application here, we hope to give some idea of the types of motors available and why certain types are used on specific applications.

Jan 1, 1963

By Robert J. Uffen

YOU will likely recall the accomplishments of the International Geophysical Year of 1957, with its polar expeditions, the discovery of the Van Allen radiation belts and the spectacular launchings of the first artificial earth satellites. Our know ledge of the exterior of the earth was greatly increased by this international, friendly, cooperative scientific investigation. The Inter-national Union of Geodesy and Geo-physics has now been joined by the new International Union of Geological Sciences in sponsoring a similar study of the earth's interior. The program will extend from January, 1962 until December. 1964, and is known as the International Upper Mantle Project. During the T.G.Y studies of the interior of the earth were relatively neglected, even though the same international •Cooperation in obtaining simultaneous world-wide observations, by similar instruments, is required to locate and study earth-quakes, for example, as it is to study the earth's upper atmosphere. The upper mantle is 1•emote from man, as it extends from a depth of about 10 km. to perhaps 1000 km., but its practical importance is great.

Jan 1, 1962

By W. J. D. Stone

"For several years, the existence of a deposit of barite (BaS04) near Brookfield, Nova Scotia, has been known. A very large deposit of strontium (SrS04) near Sydney, Cape Breton, is a more recent discovery. Cape Chemical Syndicate has been formed to work the deposits. A five-million-dollar integrated mineral processing and chemical plant is planned for Sydney to produce various compounds of barium and strontium. The mineral processing plant includes the Jones Wet Magnetic Separator and will produce high-purity barite and celestite. These products will be processed further in the fine grinding plant and the chemical plant. The general project is described, covering the deposits, processing and markets."

Jan 1, 1969

By E. Chiyangwa, L. Schoeman

The commercially successful electrowinning and refining of metals typically requires the optimization of the electrolyte composition and operating parameters to produce high quality compact electroplated metal. The prediction of the effect of the electrolyte composition on the structure and morphology of the plated metal remains a challenge. Initial work on the use of polarization measurements to predict and control plating behaviour in electrowinning plants involved potentiodynamic polarization but proved unsatisfactory as accurate and repeatable predictions could not be achieved. The aim of the present work was to develop a reliable galvanodynamic technique specifically applicable to the plating of zinc from sulfate electrolytes with which plant operation may be controlled and optimized. Initial results indicated that plating and nucleation potentials could be measured accurately and repeatably and that the relationship between the two could be used as a predictive tool for the effect of electrolyte composition on the quality of zinc electrodeposits.

Jan 1, 2014

By R. F. Baxter, C. M. Read, R. I. McCulloch

"Globalization of the aluminium industry continues to increase the pace of change and the intensity of competition, while simultaneously, society demands better products, cleaner technologies and sustainable industries. Bechtel, a global engineering, construction and project management company, is not immune to either the opportunities or the challenges created by globalization. However, and not withstanding the challenges, for aluminium industry ""players"" with a true global perspective, globalization presents very real opportunities that may be leveraged to deliver value creating goods and services. The following paper will focus on the exploitation of one of the opportunities created by globalization in the Knowledge Management domain - the application of high level tools and methodologies to improve global delivery of greenfield and brownfield aluminium smelter construction projects. Specific examples will be presented of value driven solutions that were delivered at the early stages of project engineering."

Jan 1, 2006

By J B. Maughan

Gas and oil seeps have been known in Quebec for more than one hundred years. These occur in three main areas which contain sedimentary rocks with a total thickness estimated to vary from 6,000 to 20,000 feet. The strata in these areas are similar in many respects to those in producing areas of southwestern Ontario and the Appalachian basin, and the prospects for finding and developing commercial reserves of oil and gas in Quebec would therefore also appear to be favourable. Little of the exploratory drilling to date has been con-ducted in a systematic manner, and most of the drilling has utilized improper or inadequate equipment. Many wells have also failed to adequately test and fully evaluate the principal zones of interest. Relatively high drilling costs have hindered systematic exploration; however, with improved portable equipment, it is expected that future wells can be drilled with greater efficiency and at less cost. Most of the mineral rights in Quebec are held by the Provincial Government, and acreage can still be leased in large blocks on favourable terms.

Jan 1, 1964