Search Documents

By Roy EI. Durr, Glen R. Davidge

"This paper presents the results of structural analyses and full-scale destructive tests conducted on liner plate culverts. The purpose of this work was to establish a design method and evaluate the suitability of using these structures in potential roof-fall areas for a rehabilitation application in lower stress and relaxed mining environments. Field evaluation of the design is currently in progress.Theoretical ultimate resistance functions were established for two different culvert shapes and were found to be representative of their experimental behaviour. The ultimate resistance function was used to determine their plastic behaviour to a rapidly increasing deflection condition, to determine the energy absorption capacity of these structures, and to predict their response to impact loading.IntroductionThe Kidd Creek mine of Falconbridge Limited is located justnorth of Timmins, Ontario. The area under rehabilitation for which this program was developed is the 2600 level of the No. I mine. The problem of effectively securing selected drifts at the 2600 level in NO.1 mine, for access to a high-grade ore block, is key to the economics of the operation. Diamond drill test holes had indicated a loosened rock mass above the 2600 level of about 7.5 m thick in response to the extensive mining operation below this level. This level forms the arbitrary boundary between the No. I and No. 2 mines, and has extensive volumes of cemented rock fill below it and largely untouched ore above it to the 2000 level in the North orebody. The walls at that level were showing relaxed ground conditions typical of de-stress: sub-horizontal joints opening up, and peeling.Due to the ground conditions, the consequent safety risks, the high grade of the ore, the potential production delays, and the likelihood of several phases of rehabilitation, regularly used drift rehabilitation employing rock bolts, cable bolting, or shotcrete was not practical. Two options were deemed possible alternatives to suit these conditions, steel sets with blocking and lagging, and liner plate culverts with backfill. Culverts were chosen."

Jan 1, 1995

By I. G. L. Sinclair

"ABSTRACTTill geochemistry was the principal exploration tool employed by Selco in the investigation of a zinc prospect in Lanark Township, Ontario. The geochemical studies were undertaken after the discovery at surface of marble boulders containing bands of sphalerite and lesser amounts of galena.The source of these mineralized boulders was sought by means of B-horizon soil geochemistry, followed, where appropriate, by back-hoe trenching and till sampling. The thickness of the tiff in this part of Ontario seldom exceeds 3 m or 4 m and it was generally possible to sample complete profiles of the till and thus to obtain detailed information concerning the dispersion of zinc. Drilling and trenching at the up-ice extremity of the zinc dispersion trains showed the source of the float to be sub-economic bands of sphalerite in the Grenville marble. IntroductionTill geochemistry was used extensively by Selco during the period 1975 through 1980. It was the principal exploration technique employed in a program seeking carbonate-hosted lead-zinc deposits of the Balmat-Edwards type in the Grenville rocks of southeastern Ontario. This paper describes the use of the method to locate the bedrock source of a group of sphalerite boulders found at the surface near the village of Hopetown in Lanark Township (Fig. I) . Geochemical investigations at this locality were the subject of a previous publication by the author (Sinclair, 1979).All of the analytical work related to this project was done by Bondar-Clegg & Co. Ltd. in their Ottawa laboratory. In all cases the -80 mesh fraction of the till was analyzed. The total zinc content was determined by atomic ab sorption spectrometry after hot aqua regia digestion; readily extractable zinc was determined by atomic absorption after samples had been cold-leached for 18 hours in an ammonium citrate hydroxylamine hydrochloride solution, the pH of which was adjusted to 8.5"

Jan 1, 1986

By F. Rosenblum, P. Spira

"A correlation has been established between the oxygen demand of Brunswick Mining and Smelting ore and flotation results at the bench, pilot plant and operating plant scale. A method of dete""1llining the aeration requirement of sulphide ores on the basis of this correlation is presented. It is shown that abraded iron from grinding media plays an important role in aeration and flotation. Laboratory grinding must therefore be conducted under controlled conditions with suitable grinding media in order to obtain the true aeration requirement of the ore.A method of evaluating aerator efficiency, also based on oxygen demand measurements, has been used successfully at Brunswick Mining to design pilot plant and full-scale aeration systems.1. IntroductionPre-flotation aeration of sulphide pulps has been practiced in the Noranda Group for many years to help in the depression of pyrite and pyrrhotite and to promote chalcopyrite and/or galena. Recently, two out of three parallel circuits at the Brunswick Mining and Smelting Corp. Ltd. concentrator have been converted on a test basis to a new flowsheet incorporating aeration as a basic step. Among other benefits, a substantial decrease in the middlings load has been achieved as a result of improved pyrite rejection. There has been increasing interest in other organizations in the potential advantages to be derived from' aeration in terms of improved metallurgy and/or decreased reagent consumption."

Jan 1, 1978

By M. P. Filion, K. Ferguson, L. L. Sirois

Acidic drainage is the largest single environmental problem facing the Canadian mining industry today. Technologies to prevent acidic drainage from occurring in wasterock piles and tailings sites, and on the walls of open pits and underground mines, need to be developed and demonstrated. There are two groups in Canada which have accepted this challenge: the national Mine Environment Neutral Drainage (MEND) program and the British Columbia Acid Mine Drainage (BCAMD) Task Force. This paper summarizes the activities of these two organizations.

Jan 1, 1990

By J. A. MacLellan

"CONSTRUCI'ION OF SHERRITT'S CONCENTRATORSSherritt Gordon is operating two mills north of the 56th parallel, and is presently engaged in building a third. The author was closely involved in the design and construction of all three of these concentrators.The Lynn mill is the oldest of these three concentrators-it is a 4,000 ton per day nickel-copper plant built in 1953. The Fox mill is a 3,000 ton per day copper-zinc concentrator built in 1970. The Ruttan mill will be a 10,000 ton per day copper-zinc plant scheduled to go on line in July 1973.LYNN MILL The Lynn mill including the crushing, concentrating, drying and load out plant is about 69,700 square feet or 17.4 square feet per ton per day. '!his plant was originally built in 1927 at Sherridon, 150 miles south of Lynn Lake, as a 2,000 ton per day copper-zinc plant. In 1952 the plant was moved by tractor train to Lynn Lake. The whole plant was re-oriented within the original perimeter walls as a 2,000 ton per day nickel-copper plant. This plant was expanded to 4,000 tons per day by the addition of t1-Jo rod mills and a 5-1/2 short head crusher in 1959.The Sherridon mill processed its last ore in Sherridon in September 1951 and the first load of nickel concentrate was loaded at Lynn Lake on November 9, 1953 when the railroad arrived at Lynn Lake.The site for the Lynn Lake mill was cleared of overburden in the summer of 1952 and foundations for structural steel and SO!l8 equipment foundations were poured the late summer and fall of 1952 • Steel was erected from January to June 1953. Most of the equipment came in from January to March of 1953 by tractor sleighs. Sane sleighs upset but no equipment was lest through the ice."

Jan 1, 1972

By T. M. Siew

"This paper begins with a brief discussion of the geology of the Newfoundland Zinc Mine area. The results of groundwater studies and pumping tests are then presented. It was decided that groundwater in the mine could best be controlled by conventional sump pumping and grouting. The system is fully described, as well as plans for improvements on the method. LocationThe Newfoundland Zinc Mine is located in the Great Northern Peninsula of Newfoundland, six miles northeast of Daniel's Harbour. The mine is situated at an elevation of approximately 350 feet above sea level, 5 miles farther inland , west of the long range of mountains which rise abruptly with elevations of over 2,000 feet above sea level.GeologyThe ore deposits occur in lower Ordovician carbonate rocks that form part of the stable St. Lawrence platform, which is mainly composed of (1) the lower Cambrian Labrador group, (2) the upper Cambrian to lower Ordovician St. George group, (3) the disconformity overlying Middle Ordovician limestones and shales of the Table Head formation and, (4) two overlying klippen composed of Cambrian and lower Ordovician rocks.The ore deposit is a Mississippi Valley type of the Tennessee variety, having proven are reserves of 5.3 million tons averaging 9.70/0 zinc from eleven ore zones which exist in an area of 5.5 square miles.Among these ore zones, the L zone is the major underground mining area, and is by far the largest of the known deposits. It has proven are reserves of 3.4 million tons with 11.5% zinc; this underground development has been inprogress since 1974.Stratigraphically, the orebody, which occurs about 300 feet below the disconformities between the Table Head and St. George formations, is situated in the upper St. George formationof lower Ordovician age.The upper St. George formation of the L zone is divided into three main units (Fig . I) : the underlying lower limestone the middle grey dolomite pseudo breccia unit and the overlying siliceous dolomite unit. In this area of the mine, the beds of the St. George formation dip gently west to northwest to 10 to 15 degrees. The orebody, which is generally strata controlled with a southwesterly plunge and which has the form of thin, narrow, but elongate, en-echelon ore bed s, is contained in grey dolomite pseudo breccia. Its dimensions vary from 50 to 900 feet in width and 8 to 120 feet in thickness, and the over-alllength exceed s 6,000 feet.The surficial deposit of the area is a till comprising a heterogeneous mixture of sand, gravel, cobbles and boulders, with an average depth of 20 feet."

Jan 1, 1980

By Thomas C. Poulter

Abstract The Poulter seismic method of geophysical exploration is an attempt to obtain an increased efficiency in the conversion of the energy of an m~pl06ion into useful energy which has directive properties and which contains a minimum of random frequency and random phase relations. Very little effort has been made in the past to simplify OT even control the uniformity of the seismic energy being introduced into the ground. The Poulter seismic method is also an attempt to improve the signal-to-noise ratio not merely by trying to complete the impartial filtering done by the earth on ,the continuous spectrum of primarily high-frequency energy radiated from a shot point but by applying a frequency control at the point of origin of the seismic wave. The energy from a shot-hole charge is peaked in a frequency which is much higher than will be transmitted through the ground, and its absorption introduces background interference. Only 10 to 20 per cent of the seismic energy of a shot-hole charge .is directed downward in a 90-degree vertical cone, whereas, from a pattern of charges detonated above the surface of the ground, 85 per cent of the seismic energy is included in a 90-degree cone and in some cases it is even confined to as small as a 30-degree cone. This greatly reduces the horizontally distributed energy, thereby producing a marked improvement in the signal-to-noise ratio. The frequency of the signal energy may be peaked in a rather narrow range by the proper application of two or more impulses upon the surface of the ground controlled as to direction, magnitude, and timing. These impulses may be controlled by the reflection shock wave technique, the pressure pulse technique, and the sequence firing technique, using the primary controls as outlined. The information obtained from the study of directivity of seismic energy in a high velocity, uniform material such as the ice on Taku glacier, in the Juneau ice field in Alaska, has been of great assistance in the application of the method to oilfield and mining problems.

Jan 1, 1950

By L. Dekker

"In 1979 Chevron Standard Limited and Irving Oil Limited intersected a thick, high-grade sylvinite zone in the Windsor Group in the Chevron Irving Malagawatch No. I well in central Cape Breton. This well was the third and final hole of a program designed to evaluate a non-commercial oil discovery made by Chevron Standard's Mineral Staff in 1978 while carrying out base metal exploration. Nine holes were subsequently drilled to evaluate the significance of the potash discovery. The delineation drilling proved the Malagawatch structure to be complex with the potash zone showing erratic grade and thickness distribution. Based on the drill information the potash accumulation at Malagawatch is uneconomic, however, other salt ""structures"" in the Bras d'Or Basin may in time prove to have better potential.History of DiscoveryIn 1972 Cuvier Mines discovered the Gays River lead-zinc deposit (MacEachern and Hannon, 1974) which prompted Chevron Standard's Minerals Staff to carry out a study of the Windsor basins in Nova Scotia (Figs. I and 2). As a result of this program several carbonate-hosted lead-zinc prospects were identified in the basal Windsor carbonate; one of these was at Malagawatch on Cape Breton Island . In 1978, after preliminary exploration surveys, a diamond drill program commenced consisting of 5 BQ holes (Fig. 3), three of which tested the basal carbonate. Instead of the reefoid bank facies of the Gays River Formation (Giles et al., 1979), the favoured host for economic base metal mineralization, this carbonate was developed as a laminated, pelletoidal, lime packstone more characteristic of the facies equivalent Macumber Formation (Schenk, 1967). While drilling one of these holes, No. 3-78, oil scum was intermittently detected on the drilling mud. The hole was abandoned at 191 m in anhydrite, without having reached the basal limestone."

Jan 1, 1985

By L. L. Bolton

The Department of Mines as at present constituted has evolved from the organization which came into existence following the passage of the Geology and Mines Act by the Dominion Parliament in 1907. At the outset, it may be said that it is not a function of the Department of Mines, nor of any of its branches, to administer the mining rights vested in the Crown. The title to Crown lands in the provinces of Nova Scotia, Prince Edward Island, New Brunswick, Quebec, Ontario, and British Columbia ( with the exception of certain specified areas, such as Indian Reserves, Ordnance Lands, the Railway Belt of British Columbia, and the Peace River Black) is vested in the respective provincial governments ; the title to Crown Lands in the provinces of Manitoba, Saskatchewan, and Alberta, the Yukon and Northwest Territories, and in the Canadian Arctic, is vested in the Dominion Government, and matters pertaining thereto are (with a few exceptions) administered by the Department of the Interior, Ottawa. Nor are statistics of mineral production at present collected and published by the Department of Mines. This function did belong to the Geological Survey from 1886 to 1906, and to the Mines Branch from 1907 to 1920; but commencing with 192l this duty was transferred to the Dominion Bureau of Statistics, consequent upon the decision of Government to place the collection of all statistics under the direction of one officer.

Jan 1, 1929

By J. F. Hazzard, R. J. Chalaturnyk, C. Khazaei

"Various measurement, monitoring and verification (MMV) techniques are used to ensure the safety of operations in petroleum projects. One of these techniques is microseismic (MS) monitoring of the caprock. A challenge in MS monitoring of caprock is that unlike projects such as tunnelling in hard rocks, the number of recorded events are much smaller and also wide spread through the rock mass which makes interpretation of the physical meaning behind the events very difficult.In this paper, a numerical technique is introduced and validated for coupling a finite difference code, FLAC3D (Fast Lagrangian Analysis of Continua), with a discrete element code, PFC3D (Particle Flow Code). Then, a similar approach is adopted for modeling microseismic events in the caprock. For this purpose, the underburden, reservoir and overburden layers are modeled by FLAC3D. A rather small section of caprock above the reservoir is nulled in the FLAC3D model and substituted by a PFC3D inclusion. The reservoir pressures are then applied to the reservoir section of FLAC3D. Once the FLAC3D cycles, there will be induced pressures in the caprock due to its undrained response to the change in pressures within the reservoir. These induced pressures are transferred to PFC3D as boundary velocities. Then the PFC3D cycles and sends back the boundary forces to FLAC3D. This back and forth process continues until equilibrium is reached. During this process, there will be bond breakages within the PFC3D inclusion that can be regarded as MS events. An algorithm for recording the microseismic energies based on a change in local strains is also implemented. The results are then compared with real data. The effect of injection fluid temperature is also studied. No significant appearance of microseismic events was observed due to injection of CO2 in both cases (i.e. with or without considering temperature). However, this continuum/discontinuum approach seems promising for understanding the microseismic response of caprock in more detail and also using the MS data for validation of geomechanical models."

Jan 1, 2015

By J. H. Nantel, J. F. Archibald

"The presence of radon from uranium-bearing ores, waste and from backfill material introduced underground to provide ground support, work platform and waste disposal functions, requires that ventilation controls be established to maintain safe working level concentrations. One approach has been developed at Queen's University to quantify radon and radon daughter source level s and to estimate ventilation requirements necessary to maintain these safe levels.Knowledge concerning the sources of radioactive contaminants and their production quantities is of value for planning and design stages of ventilation control systems. For any given mine layout, radiation level estimates may be forecast and modified by ventilation network design where excessive production quantities may exist.Behaviour of Radon Gas in MinesRadon gas, produced from the decay of Ra-226 in a host medium, will diffuse through porous media. In areas adjacent to mine workings, radon will be liberated into the mine atmosphere. The rate of radon emanation is proportional to the rate at which radon is produced within the host material (a function of the ore grade of U308) , to the radon concentration gradient in the host pores and to the diffusion properties of the material.The radon source concentration is determined by the rate at which Rn-222 is produced by the decay of Ra-226, and by the emanating coefficient (E), or fraction of the radon which escapes from the source matrix and is free to diffuse through the pore spaces."

Jan 1, 1984

By R. D. Brown

Higher metal prices have resulted not only in increased exploration and production, but also increased activity in the purchase of mining properties and mines. This article discusses some of the basic income tax considerations to be taken into account on the disposal of an interest in a mining claim or an active mining operation. It notes the importance ofan appropriate allocation of the purchase price amongst the various categories of assets, and discusses the tax implications to both vendor and purchaser of the transfer of the comm on types ofassets involved in mining operations. In the space available, the article can only outline the basic tax considerations, and point to areas where both vendor and purchaser need to be o

Jan 1, 1980

By R. E. Lawless

The transportation challenge began with the need to move millions of tons of coal annually from Western Canada to Ontario. The paper will discuss the options which were available, the final mode selected and the economic trade-offs which were involved. It will outline the demands of unit train technology and the effect of transportation requirements on the other elements of the whole system.

Jan 1, 1979

By H. K. Olsen, B. Thomassen, H. K. Schønwandt, L. Grahl-Madsen, H. Stendal

Abstract-The central part of the early Proterozoic Ketilidian orogen in South Greenland consists of an I-type granitoid batholith transected by four regional NE-SW-trending shear zones. The batholith was probably emplaced during subduction, from the south toward the Archaean craton in the north, in a sinistral transpressional system. A regional sediment sampling program covering 5000 km2 shows a close connection between a gold-mineralized trend and one of the major shear zones within the epizonal facies of the batholith. The gold mineralization is not directly related to the major shear zones, but occurs in quartz-veined and silicified second-order structures. High-grade (up to 114 ppm Au over 6 m) low-tonnage mineralization is found within these second-order structures cutting both amphibolites and granitoids. The mineralization is characterized by negligible or small alteration halos. Gold is associated with various element combinations of enhanced As-Bi-W- Cu, which indicate that the mineralization is mesothermal in origin.

Jan 1, 1995

By H. K. Olsen, B. Thomassen, H. K. Schønwandt, L. Grahl-Madsen, H. Stendal

The central part of the early Proterozoic Ketilidian orogen in South Greenland consists of an I-type granitoid batholith transected by four regional NE-SW-trending shear zones. Thebatholith was probably emplaced during subduction, from the south toward the Archaean craton in the north, in a sinistral transpressional system. A regional sediment sampling program covering5000km2shows a close connection between a gold-mineralized trend and one of the major shearzones within the epizonal facies of the batholith. The gold mineralization is not directly related to the major shear zones, but occurs in quartz-veined and silicified second-order structures. High-grade(up to 114 ppm Au over 6 m) low-tonnage mineralization is found within these second-order structures cutting both amphibolites and granitoids. The mineralization is characterized by negligible or small alteration halos. Gold is associated with various element combinations of enhanced As-Bi-W-Cu, which indicate that the mineralization is mesothermal in origin.

Jan 1, 1995

By J. J. McDougall

Until quite recently, the coal in the Cape Breton field was won from comparatively thick seams with light cover, and from submarine areas, and the system of mining naturally followed was pillar-and-stall. This sytem permitted of cheap extraction, and enabled production from localities where other methods could not be employed to good advantage. Thus the pillar-and-stall system, applied to conditions as stated, justified its adoption. Our working seams today, however, are practically all under heavy cover, or are moving in that direction, and with this gradual increase in cover came the increased cost of roadway maintenance. At Princess colliery, the system of pillar-and-stall was followed until roof and bottom conditions became such that further operations were unprofitable, and the longwall method was then adopted as an economic necessity. This fact should be borne in mind when operating costs of both systems are being compared. The longwall method is not held as a cure for all difficulties of heavy cover, but through it these difficulties can be overcome with less expense than by pillar-and-stall. The longwall system of mining, strictly speaking, is one by which a seam of coal is totally extracted in one operation. There are, however, many modifications of longwall, and in some cases it is difficult to determine whether certain practices should be classed as longwall or pillar-and-stall, or a combination of both.

Jan 1, 1928

By S. C. Cohen, A. F. Mikkelsen

"This paper describes the improvements made to the operation of a liquid phase, 300°C, heat transfer system in the paste plant of an aluminum smelter. These improvements were achieved by replacing the original heat transfer fluid, a synthetic aromatic, with a new technology, petroleum-based product. This new fluid, Calflo HTF, provided better thermal stability, with lower toxicity, and improved plant working conditions.The procedures for fluid selection, changeout and performance monitoring are described along with a summary of control analysis over the last three years."

Jan 1, 1993

By E. Allen

Quebec Cartier Mining Company operates approximately two hundred and fifty pieces of equipment in a climate with a temperature that has averaged 27.5°F during the last seven years. The use of special-purpose lubricants, fuels, antifreeze, rubber compounds, and alloy steels have reduced the cold-weather hazards. In some areas, high-cost cold-weather protective heating devices are being eliminated with experience.

Jan 1, 1966

By Daniel Cluff

Frozen backfill for mining operations in permafrost must be delivered in such a state so as not to thermally impose on the host rock surrounding the filled stope. The placement process, the material strength demand, and the freezing time delay are the parameters that control the applicability of the method. A two-year research program was carried out in the field and using a laboratory-scale apparatus, designed to simulate a pour of frozen backfill, to study the mixing, thermal properties and segregation. The frozen rock and tailings must be at a below zero temperature and get fully wetted so the surfaces cause adherence of the particles to one another and enhance the solidification of the poured backfill. The results provided a recipe and a process for mix design for open stoping operations in cold regions. The testing evaluated the sensitivity of the test parameters that included the amount of water added in the mix, the temperare of water, the rockfill/tailings ratio, and the temperature of solid constituents.The paper presents the result of this environmentally friendly, innovative technology. The distribution of the materials and the mixing process are instrumental in achieving the properties required for open stoping applications.

Oct 1, 2010

By B. Das

"Computers have been used extensively in the mineral industry in exploration, reserves calculation, mining technology, mineral processing, etc. With respect to coal mining, there are also various applications for evaluating rock slope stability of open pits, design of open pits, underground operations, mine ventilation, ground control, data processing and management information, operations control and certain technological applications. Mine ventilation appears to be the field in underground coal mining touched on most; on the other hand, underground coal mining methods evaluation is represented only sparingly.It is therefore essential to review the status of the computer in underground coal mining methods evaluation in order to define its scope for further application. The paper discusses the roles of the mining engineer, programmer, computer operator and analyst as well as that of the computer. The important parameters will be identified and discussed along with their application for different underground coal mining methods, with their individual unit processes. Mainly, longwall face operations have been covered. Although many models have been of academic interest, they can be considered as important steps in a transition stage which will be followed by more practical applications for computers for underground coal mining method evaluations in the future. This calls for a coordinated effort from all concerned."

Jan 1, 1981