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By A. B. Irwin

Abstract The techniques used in recognizing, recording, and interpreting structures in the Slocan sedimentary ceries in the West Kootenay district of B.C. are presented here in the hope that they will be of use to others working in complexly folded areas. The general pattern of folding in the Central Slocan area is obscured by lack of outcrop over a large part of the country, lack of marker horizons, local complexities of folding, and several systems of faulting. 1t was found necessary to observe and record in great detail all primary and secondary structural features and to analyse those observations on a statistical basis. The determination of bedding tops as well as bedding attitudes proved to be of fundamental importance in determining the pattern of folding. The interpretation of secondary linear and planar structures confirm:; this pattern. Accordingly, the thickness of the Slocan sedimentary series is computed to be several times that formerly postulated. Introduction The data upon which this paper is based were collected largely during the field seasons of 1947 and 1948 when the writer was employed by the British Columbia Department of Mines on detailed mapping in the Slocan mining camp. Additional observations were made by the writer during 1950 when engaged in property examinations for the Geological Survey of Canada. This presentation is largely a condensation of part of a more comprehensive thesis (5) and is restricted to observations and conclusions pertaining to the mapping of complex folds, stripped of any hypothetical discussion. Except for some unique occurrences of primary structures, there are no features or techniques described here which are not presented in standard textbooks on structural geology. It is felt that the major contribution of this paper is the method used in applying these standard techniques to a specific field problem and in interpreting the results.

Jan 1, 1951

By G. W. Clark

"The mining of the ore bodies at Rabbit Lake has in the past been by the open pit method. This method is presently being used to develop the B-zone and will continue into the future with the development of two smaller ore bodies, the A-zone and D-zone. The Eagle Point orebody will be developed by an underground method which will provide production and employment into the next century.The ore bodies at B-zone, A-zone and D-zone are unique in that they are located under Wollaston Lake. To permit mining by the open pit method a steel-celled dyke has been constructed around the north end of the B-zone. This same dyking method will be used for the A -zone and D-zone. INTRODUCTIONMine development at Rabbit Lake commenced in 1970when a detailed engineering feasibility study established the viability of the Rabbit Lake deposit. In 1972 construction of the mill and camp site began. Construction materials were seasonally hauled to the site over a winter road until November 1973when the government of Saskatchewan completed an all-weather road to within six miles of the operation.In October 1974, stripping of the Rabbit Lake open pit began with the removal of overburden and lake bottom sediments from the previously drained Rabbit Lake. The first ore was processed by the mill in June 1975and by October the mill was producing three million pounds per year. The design capacity of five million pounds annually was first achieved in 1977 and maintained until 1981, when lower ore grades resulted in lower production rates .It was clear when mining at Rabbit Lake began that, without additional reserves, the Rabbit Lake operation had a life of less than 10 years. Exploration, therefore, continued in the immediate area in an attempt to discover additional uranium mineralization."

Jan 1, 1989

By R. A. Lunceford, K. C. Shaver

Acquired by Teck Corporation in 1990, the White Earth project, located in southwestern Colorado is the largest titanium resource in the U.S. Teck Corporation has conducted geologic, reserve, mineral processing, pre-marketing, and environmental baseline studies directed toward the economic feasibility of producing titanium pigment. The White Earth project is situated in a 31 km2 alkalic-carbonatite complex intruded into Precambrian granite and metamorphic rocks about 570 million years ago. Perovskite occurs in a 8 km by 1.2 km Acquired by Teck Corporation in 1990, the White Earth project, located in southwestern Colorado is the largest titanium resource in the U.S. Teck Corporation has conducted geologic, reserve, mineral processing, pre-marketing, and environmental baseline studies directed toward the economic feasibility of producing titanium pigment. The White Earth project is situated in a 31 km2 alkalic-carbonatite complex intruded into Precambrian granite and metamorphic rocks about 570 million years ago. Perovskite occurs in a 8 km by 1.2 km

Jan 1, 1998

By W. Standifird

"Cohesive fracture is a mechanical model widely used for modeling quasi-brittle fracture in rocklike materials. This work discusses use of this model to simulate quasi-brittle fractures generated by injection stimulation during the process of cuttings reinjection in West Africa. Cuttings reinjection is an engineering practice used for disposal of drilling waste. During this process, hydraulic fractures are created at the target formation and milled cuttings are injected with fluid. In practice, this process must remain in compliance with environmental regulations and zero-discharge policies. The purpose of this study is to determine the following factors of injection design for a field in West Africa: (1) pumping pressure capacity required to successfully perform the injection and (2) the injection rate for injection performance and the value of fracture width under injection.A simplified three-dimensional (3D) finite element model (FEM) was built. A poroelastic plastic damage model was used for simulation of the cohesive crack prorogation within the target formation. For simplicity, fracture development in both horizontal and vertical directions was simulated separately. In this way, the computational burden for one calculation was reduced to a reasonably low level, without losing accuracy of the model. Loads of the model include fluid injection and gravity, which balances the initial geostress field. Various values of injection rate were used in these calculations to determine the most reasonable value of injection pressure. The capacity of pressure of a pumping device was determined using this optimized value of injection pressure.Results in values of width and length of fractures created by the injection are presented. Injection pressures at bottom-hole (BHP) corresponding to each value of injection rate are also given. Numerical results for fracture generation and propagation in a horizontal direction were visualized. The pumping pressure capacity required to fulfill the cuttings reinjection work was determined based on the numerical results of optimized injection rates and pressure. The fracture width was determined using the given pumping pressure. The length and height of the fractures was determined using pumping pressure along with the required volume of cuttings waste to be disposed of into the formation.This work presents a case study of 3D finite element modeling of hydraulic fracturing generated by cuttings reinjection. The results of the optimized injection rate and pressure provide a best practice and a useful reference for cuttings reinjection analyses in this region."

Jan 1, 2015

By D. A. Peterson, R. Pakalnis, G. Peter Mah

"Laboratory and trial installations have been completed to determine the potential of composite cable bolt reinforcement in Canadian underground mines. Several prototypes of glass fibre cable bolts have been developed and tested, two of which are currently available to the mining industry. Their evalualtion consisted of lab testing in Canada and the United States, along with trial installations in several underground mines throughout Canada. The objective was to develop a cost competitive composite cable bolt equivalent in strength to that of a 16 mm (Ys in.) diameter steel cable bolt. In addition to achieving equal or superior load carrying characteristics in tension, the glass fibre cables generally experienced an increase in the rate of installation due to their lighter weight. Unlike conventional steel cables, composite cables may be installed within mines which utilize continuous excavation and which require cuttable support. A market analysis of cable bolt usage in Canada has been completed. Glass fibre cable bolts are an effective means of rock reinforcement in mining applications. They prove to be a viable alternative to conventional steel cable bolting. IntroductionCurrent cable bolting practice consists of cement grouting one or more steel cables within a drill hole in order to support the surrounding rock mass. Cable bolts are a form of internal support and are generally used as pre-support in open stope and cut-and fill mining methods. They can be either tensioned (active support) or untensioned (passive support) and may be of any length, though for underground mining applications, are generally less than 20 m (65.6 ft) and are untensioned. A major advantage of cable bolts is that they are flexible and can be coiled to approximately 1 m (3.3 ft) diameter coils. This allows relatively long lengths (>20 m, [65.6 ft]) to be installed in areas with limited head room (1.8 m)."

Jan 1, 1994

By A. Pawelczyk, D. Hreniak, E. Zych, W. Strek, K. Grabas, A. Ostrowski

"Mongolia is a country rich in rare earth resources. In the experiments carried out samples of the Mongolian ore were processed to obtain a lanthanide concentrate. The concentrate underwent hydrometallurgical processing. At the same time radioactive elements were removed. The lanthanides were obtained in the form of hydroxides that were further processed in order to get concentrated products. As a result cerium, lanthanum and neodymium-praseodymium concentrates were separated in the process. Also a concentrate of remaining elements: samarium, europium, gadolinium, terbium, dysprosium, holmium and erbium was obtained. INTRODUCTIONAccording to the assessment of the US Geological Survey, Mongolia possesses 16.77 % of the world total rare earth (RE) resources (Daly, 2011); that is the second largest RE reserve in the world, estimated to be 31 million tonnes in terms of rare earth oxides (REO). In the face of Chinese RE trade restrictions, Mongolia emerged as an important economical partner in mining and exploitation of these critical raw materials. This country is recognized as having more than five large RE deposits in the southern provinces. The most important are Lugeengol (Lugin Gol), Mushgia Khudag, Khotgor and Khalzan Buregtei (Eurasia, 2010). The Mongolian government has taken measures to facilitate western investments, nevertheless the country is economically dependent on China, the basic trading partner, particularly where exports are concerned.In the late 1970s Hydromet Kowary Enterprise, Poland, took up, along with the Wroclaw University of Technology, research and technological study on lanthanides recovery from raw materials of Vietnamese and Mongolian origin and from Indian monazite sands (Kowalczyk, 1990; Kowalczyk & Mazanek, 1987; 1990). For that purpose, a rare earth processing plant had been constructed with the capacity of about 10 t/year of hydroxide concentrate. The facility included several technological operations like grinding, flotation, hydroxide concentrate production in the hydrometallurgical processing, particular RE separation, and production of commercial products in form of CeO2, La2O3, Nd2O3, Pr2O3, and misch metal. Additionally work had been carried out in Kowary on the manufacture of yttrium and europium oxides of high purity, which were intended for color TV picture tube production in Poland."

Jan 1, 2012

By A. Sutherland Brown

"The Red Rose Mine is in the Rocher Deboule Range, 8 miles south of Hazelton. The mill camp (elevation 4,000 feet) is on Red Rose Creek, 11 miles by road from Skeena Crossing. The mine camp is one mile northeast and 1,600 feet above the mill camp on a spur of Red Rose Peak.The Red Rose mine was described in the Jubilee Volume, Structural Geology of Canadian Ore Deposits (Davis, pp. 129-131), but regional geology and mine development have progressed to a stage at which a more complete description is possible.The property was first located in 1912, and for the next 7 years was prospected actively for gold and copper on the southern extension of the Red Rose shear. Scheelite was first discovered in the vein in the northern part of the shear in 1923. The Consolidated Mining and Smelting Company of Canada, Limited optioned the property in 1939, and after a drilling program in 1940 the present mine development was initiated in the vein in the northern part of the shear. A 75-ton-per-day mill started operating early in 1942 and continued until 1943. The property was inactive until 195 l, when Western Tungsten Copper Mines Limited leased the property from The Consolidated Mining and Smelting Company of Canada, Limited. A mill, which later was enlarged to 140 tons per day, started operations at the end of 1951. The mine and mill were closed in December, 1954.The mine has twelve levels and sub1evels, and most of the workings are in the plane of the vein (see Figure 2a). The level interval is not constant, but between the lower four levels is 87 feet (100 feet in the plane of the vein). Access is provided by four adits; the 800 (elevation 5,659 feet), 600 (5,920 feet), 300 (6, 133 feet) and 200 levels (6,237 feet). The 600 level is the main haulage, and from it the ore is transported to the mill by aerial tram. From this level an inclined shaft extends in the vein to the lowest level (I, 100)."

Jan 1, 1949

By J. Keith Haddock

"Introduction The Boundary Dam Mine is located 5 km south of the City of Estevan, Saskatchewan and is operated by Manitoba and Saskatchewan Coal Company Ltd., one of the Luscar companies. The entire production of 1.7 million tonnes per year is delivered to the Boundary Dam Generating Station of Saskatchewan Power Corporation. Geology There are basically two seams mined on the property, the main Estevan seam ranging in thickness from 3.0 m to 4.5 m with partings and the upper Roche Percee seam (roughly 15 m to 23 m above the Estevan) which ranges from 0.6 m to 2.0 m in thickness. Most of the reserves are concentrated in the Estevan seam, the Roche Percee only being mined whenever its thickness makes it economic to recover. The coal measures belong to the Ravenscrag Formation of Tertiary (Paleocene) Age. This formation is widespread in North Dakota and Montana and contains the lignite fields of North Dakota and subbituminous coals of Montana. The formation is gently tilted to the southeast at Boundary (0.5 degrees) and consists of weak sandstones, siltstones and silty mudstones. Reserves and Coal Quality The present minesite encompasses a coal reserve of approximately 50 million tonnes calculated to a maximum stripping depth of 37 metres or 20:1 mining ratio. The reserves form only a part of the total reserves in the Estevan area which are owned by the Saskatchewan Power Corporation. The coal being mined is classed as Lignite ""A"" and has the following specifications:"

Jan 1, 1985

By T. E. Warren, K. W. Bowles

"IntroductionTHE PROBLEM of producing synthetic liquid fuels from coal and other raw materials is of increasing importance in Canada as well as in the United States. This is due, to a large extent, to the continually increasing demand for gasoline and other liquid products which are now obtained solely from petroleum. The United States has reached a position where domestic supplies of crude petroleum must be augmented by imports and Canada is still a long way from self-sufficiency. In the event of war, there might well be an immediate need to find supplementary sources of liquid fuels. It is, therefore, expedient to consider alternative sources of production now -well in advance of the time when supplies of petroleum may prove inadequate to meet requirements.The purpose of the present paper is to give a short review of the history of liquid fuel production from coal, to describe briefly the research sponsored by the Federal Government on the coal hydrogenation process, and finally to evaluate the present status and future trend of the synthetic fuel industry, with special reference to necessary research work.History of the Oil-From-Coal IndustryThe history -of coal liquefaction began in 1913, in Germany, with the work of Frederick Bergius. His first approach to the subject was not deliberately planned."

Jan 1, 1952

By A. E. Cameron

The theory of atomic distribution of the stranger atoms in the space lattice of the solvent metal has been well developed by Rosenhain. It has long been known that the addition of one metal to another to form a solid solution increases the strength and hardness of the solvent metal. This increase is practically proportional to the amount of added substance up to the limit of solid solubility. To account for this increase in hardness and strength, Rosenhain assumes that the stranger atoms occupy positions on the solvent metal space lattice. Atomic attractions about the stranger atoms will not be the same as in the case of the pure metal, and there will thus be a disturbance of the orderly arrangement of the atoms on the space lattice, or a distortion of the lattice. Such a disturbance would interfere with the ease of slip along the planes and would thus tend to promote strength and hardness. Rosenhain notes that not only may there be a local disturbance of the lattice about the stranger atom but there may well be also a measurable change in the dimensions of the lattice as a whole. The relative amounts of local and general distortion of the lattice will depend upon the nature of the lattice itself. As Rosenhain says, "If the lattice is comparatively soft and flexible the distortion is likely to be largely local. In a stiff lattice, however, local distortion will be resisted and there will be a correspondingly increased general distortion."

Jan 1, 1927

By D. M. Xue, T. B. Li

"With the increase of human engineering activities, global climate change and active plate tectonics movement, the giant landslide frequently occurred in southwest China, which caused huge property and human losses. Besides, the potential landslides pose severely threaten to the construction and operation of airports, railways, highways and power stations etc. In order to provide accurate guidance for the landslide investigation, stability analysis and mitigation, the giant landslide is redefined according to landslide volume, depth of slip surface, complexity of landslide mechanisms, and degree of landslide mitigation difficulty, and classified with the typological classification approach based on the twofold attributes of landslide behavior including formation mechanisms and reactivation features. Finally, the threefold particularity of the giant landslide is also summarized, which enables a more effective landslide mitigation design.INTRODUCTIONWith the increase of anthropogenic activities, global climate change and active plate tectonics movement such as continual uplifting of Qinghai-Tibet plateau and strong earthquakes, the occurrence of giant landslides was in ascending trend in southwest China (Huang, 2009), which caused serious destruction, and greatly endangers such engineering construction from safety, time and economic aspects as airports, railways, highways, power stations, etc. Giant landslides have huge scale, complex formation/reactivation mechanisms and mechanical behavior. They may not be identified during the hazard investigation, but may be firstly initiated or reactivated due to the following engineering activities, heavy rainfall or strong earthquakes. Consequently, the landslide mitigation is inevitable and costly. However, it is difficult to control the deformation of giant landslide with lack of a correct understanding of genetic mechanisms (Marui, 2012; Zhang, 2000) and the excessive large sliding forces of the slide blocks calculated by the conventional limit equilibrium method. For instance, the failure of anchored pile wall for the No.102 giant ancient landslide (Zhu et al., 2012) and stabilization measures for the Sidi Rached viaduct landslide(Guemache et al., 2011); four rows of piles had not prevented the occurrence of the No.12 landslide in a high fill slope in the Panzhihua airport (Li et al., 2012)."

Jan 1, 2015

By T. T. Wang, T. H. Huang, S. S. Zhan

"Fractures with diverse features dominate the hydraulic behavior of fractured rocks and are one of the major subjects for hydrogeological characterization of a site. This study investigates curve patterns obtained by packed tests, and as well the influence of fracture features based on 59 sets of in situ packer tests with different fracture combinations and fracture features. The result shows that, in the example of Heshe site, neat and tidy fractures usually provide stable channel for water flow during testing, and the hydraulic properties of fractures infilled with breccia and mud may change during testing because of leaching and/or washed out of infilling breccia and mud. Different combinations of fractures with diverse features in packed test sections lead to different curve patterns for in situ hydrogeological tests. For groundwater flowing predominately through neat and tidy fractures, the pressure-discharge curve of modified Lugeon tests are usually linear curve pattern, and the pressure decrease while the discharge increase in pressure-discharge-time curves of single-hole double packer tests, which benefit statistically determining the transmissivity of dominant fracture sets. INTRODUCTIONFractures interlaced in rock masses are major channels for groundwater flow and generally account for the anisotropic and heterogeneous characteristics of permeability for fracture rocks. To describe reasonably the permeability of a fracture rock, the Discrete Fracture Network (DFN) approach and others with similar ideals have been developed. Many methodologies and associate equipment, for instance, the televiewer and the in situ hydrogeological test, have been proposed to investigate the spatial distribution and the transmissivity for different fracture sets, which are two main parameters necessary for the DFN or similar model simulation (Pearson & Money, 1977; Barker & Black, 1983; Hsieh et al., 1985; Bernard et al., 2006; Quinn et al., 2012). However, diverse outlooks for the pressure-discharge curves and the temporal pressure and associate temporal discharge curves often confuse the investigation results by significant deviations on derived permeability (Houlsby, 1976; Zlotnik, 1994; Royle, 2009; Camilo, 2010).Aiming on technical development for in situ hydrogeological tests and fracture investigation, an experimental well site with 10 wells has been established in Heshe in central Taiwan since 2011 (Wang et al., 2011; Song, 2012; Zhan et al., 2013). Extensive geological survey and well-hole scanning by a televiewer provide spatial distributions and outlooks of fractures in detail. Additionally, a series of Lugeon tests, double packer injection tests and pumping tests have been performed to investigate the permeability of fracture rocks, and dominate fracture sets as well. Based on the results obtained from the Heshe site, this study classifies the curve patterns of hydraulic packer tests. The features of fractures involved in packed sections for packer tests are then inspected in detail. Relationship between the curve patterns of hydraulic packer tests and associated features of corresponding fractures in rock are discussed and addressed accordingly."

Jan 1, 2015

By R. L. Brown

The burning sulphide ores in the Sullivan Mine generate sulphur dioxide gases. This paper is concerned with a description of the environmental impact of SO2 on air quality in the mine and on the surface in the vicinity of the mine. As a result of surface caving, SO2 has been able to vent to surface and winds have carried it into one residential area of Kimberley. Monitoring practices are described.

Jan 1, 1977

By A. D. Hunter, J. M. JR. Moore

"The Aldermac deposit and associated prospects occur in the Noranda Archean volcanic centre of the Abitibi greenstone belt. Over two million tons of are grading 1.65% copper, with minor gold and silver, were mined between 1933 and 1943. The deposit has features in common with the Vauze and Millenbach mines in the same district.Recent detailed mapping, geochemistry and petrography combined with data from former diamond drilling and mining operations permit a re-interpretation of the Aldermac area. The orebodies and spatially related sulphidic zones are con eluded to be volcanogenic.The host rocks are a chemically bimodal suite of mafic and rhyolitic flows, volcaniclastics and related subvolcanic intrusions. Massive sulphide lenses are spatially related to a quartz-feldspar- phyric rhyolite dome and siliceous, volcanic-exhalative sedimentary rocks, The succession is cut by gabbro and syenite, related to later stages of volcanism, and by post Kenoran diabase dykes. Regional metamorphism attained the low greenschist facies, but the rocks lack penetrative deformation.Hydrothermal alteration is primarily an intense silicification of mafic volcanic rock s enveloping, or lying below, sulphidic zones. Chlorite and sericite alteration zones, including dalmatianite, are more locally developed and have a closer spatial relation to mineralization, as do epidote, calcite and calcic garnet.The structure is complex and cannot be explained by isoclinals folding; rather it reflects concurrent faulting, and extrusive and intrusive activity. Fault blocks were rotated and exhibit opposed facing; the original selling was possibly a submarine graben.Sulphidic zones occur within mafic and felsic volcanic rocks and at the interface between the two; there is thus potential for discovery throughout the known stratigraphic succession. Exploration conducted according to a volcanogenic model is advisable, particularly in the light of recent discoveries in similar rocks of the Amulet area."

Jan 1, 1983

By Lorne Sivertson, Peter Kitrredge

"World metallurgical coal imports totalled 110million tonnes in 1978. Of this amount, Japan imported 50 million tonnes, making it by far the largest and most important coking coal market . British Columbia and Alberta exported 12.0 million tonnes of coking coal in 1978, or 11% of the world total. Virtually all of these exports were directed to Japan, making up 22% of total imports.Some observers have suggested that because Japan is almost the exclusive buyer of British Columbia and Alberta metallurgical coal, the benefits of the coal trade may be primarily on the side of the powerful Japanese buyers. Buttressing this suspicion is the fact that Japanese trading companies have taken substantial equity positions in B.C. coal mines, thus presenting the possibility of non-arms-Iength transfer arrangements. There is then at least some evidence to support the hypothesis that Canada's western coal producers receive prices that are less than would prevail in a more competitive market; that is, that they are exploited.This paper produces evidence that Canada's coals are not underpriced in respect to U.S. and world markets. The conclusion is drawn that British Columbia and Alberta metallurgical coals receive prices that are equal to prices known to be competitively determined. This conclusion follows an in-depth analysis of prices, coal qualities and the economic characteristics of all major coals traded in the Japanese market. A by-product of the analysis is an equation capable of predicting the value of any metallurgical coal sold to Japanese buyers, or, for that matter, any buyer. Hopefully, this can be of some use to coal producers in developing their marketing strategies."

Jan 1, 1980

By Kati Tschöpe

Cathode wear has become an increasing challenge in the aluminum industry due to the use of more graphitized materials. Today, there exist no standard laboratory methods for measuring cathode wear where different commercial materials can be ranked. The typical average wear rate in an electrolysis cell is quite small. The aim of this work was to design a test method where the wear could be accelerated compared to industrial cells. It was focused on polarized tests where the cathode is exposed to electrolyte, which gives higher aluminium carbide solubility. The cathode materials were characterized by microscopy and image analysis.

Jan 1, 2011

By R. B. Fermor

"The tyndalloscope is used in Europe for dust-hazard assessments in both coal and metal mines. Dust-hazard conditions can be directly evaluated by the tyndalloscope in many underground working situations, once the basic standard table or tables have been prepared from representative mine-rock samples.The tyndalloscope is excellent, in many cases, for diagnostic dust sampling during a working shift, because individual readings can be taken to within three-minute intervals. The limitations of the tyndalloscope are also discussed.The author suggests that a combination of both the tyndalloscope and gravimetric sampling methods would be an ideal match for most mine dust-hazard assessments."

Jan 1, 1970

By Andrzej Luszczkiewicz, Magdalena Duchnowska, KGHM Polska Miedz S. A., Witold Pawlos, Jan Drzymala, Alicja Bakalarz, Przemyslaw B. Kowalczuk

A pre-flotation process of the Kupferschiefer ore with only frothers produces a concentrate enriched in carbonaceous matter and tailings for further upgrading steps. A partial removal of easy-to-float components of the feed before the main enrichments steps by flotation (rougher, scavenger) improves overall efficiency of separation of valuable elements from the ore. Since the types and doses of frother used for pre-flotation effect the process, the aim of this study was to determine the influence of selected frothers on the efficiency and selectivity of the Kupferschiefer ore processed by KGHM Polska Miedz S.A. A series of pre-flotation tests in the presence of different poly(propylene glycols) ethers, poly(ethylene glycols) ethers and aliphatic alcohols were conducted. The obtained results indicated that the types and doses of frother determine the flotation selectivity of copper and total organic carbon. The evaluation of the pre-flotation process was based on the analysis of selectivity parameters calculated from the recoveryrecovery Fuerstenau upgrading curves as well as the values of copper and organic carbon grades in the flotation products. It was shown that pre-flotation performed in the laboratory scale using a suitable frother provides higher overall flotation selectivity of organic carbon with lower overall flotation recovery of copper in comparison to flotation without the pre-flotation step. Thus, the pre-flotation process improves the quality and quantity of the final concentrates produced from the Kupferschiefer ore.

Jan 1, 2016

This paper states how alloy and welding advances have made possible the rapid development of the use of aluminum in the construction of equipment for earth moving and off -highway rock hauling. The main details are given regarding the construction and field testing carried out on an aluminum prototype body. The test results of strain gauge readings are analysed, and a description is given of how these have been applied in subsequent designs. The increase in the number of aluminum units put into the various types of service in Canada, as well as the problems encountered, is described, and the experience gained from five years of field service is discussed in some detail. An assessment is also made of the durability of the e units. The economics of using aluminum, together with the current development position, are reviewed, and predictions are made for considerable future increases in the use of aluminum units in open-pit and off-highway operations.

Jan 1, 1964

By V. Shumila, T. Butler

Microseismic monitoring systems listen to a rockmass and record ground vibrations associated with brittle rock fracture. Modern systems record continuously and can identify as many as one thousand small and possibly larger magnitude events occurring each day from induced stress change and redistribution. This paper presents examples of the real time use of microseismic information in mining applications. It shows how alerts can quickly identify large magnitude events or unexpected clusters of seismicity and how seismic re-entry protocol can help to improve safety decisions. Additionally, newly developed advanced analysis techniques applied to mine seismic data sets are shown including the use of clustering methods to see into a cloud of seismic data to identify significant activity and quantify possible planar features. The use of source parameter trend analysis is shown to be a beneficial method for interpreting changes in relative stress levels. Seismic moment magnitude distributions are analyzed using the TGR (Truncated Gutenberg Richter) and TMD (Tapered Moment Distribution) methods to estimate bvalue and expected maximum magnitude. Seismic hazard analysis is shown as a useful way to simplify a dataset and highlight seismic hot spots. The rockmass response to excavation is a complicated spatial and temporal process and microseismic monitoring is a method that can be used to help understand the location and mechanics of failure occurring in the rock ultimately helping to improve safety and productivity at a mine site.

Jan 1, 2015