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By George Langford

Introduction The fiftieth anniversary is, for an individual or a society, an appropriate time for a review of the past so that events and experiences may be viewed m perspective, and thereby serve as a useful guide to the future. In this review of mining geology it is proposed to set forth the situation as it was when the Institute was founded, and then trace the developments during three appropriate periods-the first from 1898 to 1918 the second from 1919 to 1939 and the third from 1939 to 1948. Mining activities were widespread in Canada in 1898 and some of the operations were considered large for their day. The total value of the metals produced in that year was $21,705,854, and in the case of five metals the output had a value in excess of one million dollars. In order of importance these were gold, silver, copper, nickel, and lead. The important producing areas were ova Scotia, Quebec, Ontario British Columbia, and Yukon. This diversification of the mining areas and the metals produced created an interest in mining throughout Canada, and was an important factor in making Canadians conscious of their mining industry. In the year 1898 geology was a recognized science. The principles of physical geology were well known, but the same cannot be said of economic geology and structural geology. Ore deposits and their occurrence had been studied chiefly in Europe. A great many important observations had been made but the theories linking these facts together were still m a formative stage. The same condition was true of structural geology. These two branches of geological science which are so important in what is now called 'mining geology', had not progressed far enough to be of practical assistance mining operations. For this reason, geologists were regarded as dreamers in ivory towers-a concept chat still lingers in the minds of those who have not kept abreast of the growth of the science.

Jan 1, 1948

By I. S. Thompson

"The discovery of low-grade copper-silver mineralization near the town of Tipperary, Ireland, by Gortdrum Mines Limited was the result of reconnaissance geological and geochemical exploration followed by target delineation from induced polarization surveys.Initially, orientation studies at the Tynagh lead-zinc orebody showed that such deposits could be readily detected in stream sediments and soils using cold extraction analysis for total heavy metals. Numerous areas showing stratigraphical and structural similarities to Tynagh were then selected for reconnaissance geochemical prospecting.The Gortdrum deposit was detectable through the presence of anomalous metal values in stream sediments 3,000 feet downstream; soil sampling indicated an area of 2,000 by 700 feet containing 2 Yz to 20 times background cold-extractable metal values. Induced polarization surveys defined the dimensions and attitude of mineralization.Drilling to date has outlined (under 10 to 20 feet of till) low-grade copper-silver mineralization within Lower Carboniferous limestones and shales which have been faulted against Devonian sandstone. Mineralization ex-tends from surface to depths of 250 to 450 feet and consists of bornite-chalcocite-tetrahedrite and some chalcopy-rite in altered limestones and intrusive dikes.The deposit is geologically analogons to the Tynagh and Silvermines orebodies, but in contrast exhibits a predom-inant structural control. Provisionally, it is postulated that mid-Carboniferous folding and faulting produced the pre-mineralization high porosity via recrystallization, shearing and brecciation. Subsequently, hydrothermal solutions from the west, with a probable eommon origin to the volcanic dikes, were introduced along the fault planes. Although syngenetic causes cannot be exempted, the field relationships favour an epigenetic origin."

Jan 1, 1967

By K. Adham, C. Lee

The demand for nickel is continuing to exceed inventories, and producers are working vigorously to increase capacity. Many nickel processes utilize the fluidized bed technology for its fast heat and mass transfer, excellent temperature control and low maintenance. The following four nickel applications of the fluidized bed technology have been commercialized: I) Sulfide ore roasting; II) Nickel sulfide (matte) roasting; III) Nickel oxide reduction; IV) Nickel chloride pyrohydrolysis. This paper examines the issues surrounding the application of fluidization technology to the above processes, from the stand point of the engineer modeling the process and designing the key equipment, based on the historical success stories and the fundamental principles of flow sheet synthesis. Using the available data in open literature, typical flow diagrams (with convenient bases of 1 t/h feed or product) are developed to illustrate the relative flow rates and to highlight the key features of each application. In addition, some historical background information is provided for each process with supplemental notes with regards to our company's involvements.

Jan 1, 2005

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. T. Seaman

There are several hydrometallurgical alternative processing options under development for high enargite and arsenic containing copper concentrates ranging from biological, atmospheric, medium temperature oxidation to total oxidative leaching. The most developed of these options is the CESL process boasting pilot campaigns totaling more than 8760 hours of fully integrated continuous operation, as well as, over two thousand batch scale oxidation tests performed on dozens of concentrates for flowsheet development. This paper reports the observed deportment of arsenic under varying arsenic, iron and acid oxidation conditions; it also describes the impact of iron to arsenic ratios and residue recycle on overall arsenic behavior and its stability in residue. INTRODUCTION The CESL Hydrometallurgical Process (CESL) was originally developed to compete with smelting of clean chalcopyrite concentrates. High Treatment Charges and Refining Charges (TC/RCs) combined with premiums on London Metal Exchange (LME) grade copper from onsite refining made treatment of copper concentrates using CESL a viable option at the time. As world demand for copper increased and a subsidized Chinese refining market developed, smelting contracts became more favourable for the miner and focus was placed on modifying the CESL Hydrometallurgical Process to handle concentrates with elevated deleterious elements. Dozens of pilot campaigns processing concentrates containing elevated concentrations of uranium, fluoride, mercury and nickel all led to further developments of the CESL Hydrometallurgical Process. In 2016 a United States patent was granted for a novel modification of the CESL Hydrometallurgical Process for recovery of copper from arsenic-bearing and/or antimony-bearing copper sulphide concentrates, Henry Salomon de Friedberg (2016). To date, over 2000 bench scale tests along with five fully integrated closed loop pilot campaigns, totaling over a year of online operation time, have been conducted processing arsenic bearing copper concentrates. This paper summarizes the observed behavior of arsenic under varying autoclave and process conditions.

Jan 1, 2019

By H. Asgari, A. G. Odeshi, J. A. Szpunar

In the current research, the role of grain size on the texture formation and mechanical behavior of rolled AZ31B Mg alloy is investigated under shock loading conditions. The grain size of the original asrolled sample was 8 µm and different grain sizes, e.g. 25 and 46 µm, were produced by heat treatments at temperatures in the range of 400-500 °C. In order to evaluate the effect of grain size on the anisotropy of mechanical behavior, the samples were cut along the rolling direction (RD), transverse direction (TD) and normal direction (ND) and tested at strain rates of 900 and 1200 s-1 using Split Hopkinson Pressure Bar. Texture measurements showed that initial texture of the samples cut from the as-rolled sheet is a weak rtype texture. However, a stronger texture was observed for samples with large grains. After shock loading, a (00.2) basal texture developed in all samples and the intensity of the basal poles was higher in samples with coarser grains. This observation is corroborated by high twinning activity and possible activation of pyramidal <c+a> slip in coarse grained samples. Besides, the strength of basal texture increased with increase in the strain rate. Furthermore, the samples with larger grain size showed lower strength and higher ductility, and this was observed for all investigated strain rates.

Jan 1, 2014

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

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

Jan 1, 1967

By A. C. Stevenson

"There are many critical application issues that affect all AC drives, but there are several that are absolutely mandatory for pulse width modulated (PWM) AC drives. If these rules are not followed, the drive system will have insulation, bearing EMI or noise problems. Pulse Width Output VoltageFigure 1 shows the output current of a typical pulse width modulated (PWM) drive. This is, of course, not a clean sine wave thus will have a lot of very significant harmonics. In fact, the harmonic spectrum is directly related to multiples of the carrier switching frequency plus side bands related to the basic output frequency. A typical spectrum for a PWM source bridge switching at 5 kHz is shown in Figure 2. Notice that the spectrum has multiples of the 5 kHz switching frequency and the number of side bands gets larger as the harmonic number increases.IGBT Switching TransientsWhenever we have PWM inverter switching, voltage transients are formed that propagate (usually at about half the speed of light) down the power cables to the motor just like in a radio frequency transmission line. If we do not terminate these transmission lines (motor cables) properly, the voltage pulses will be reflected when they reach the motor end and will be transiently increased up to twice their original amplitude.This transient voltage rise, shown in Figure 3, is important for three reasons:1. Insulation Voltage Stress — Higher voltage stress in the motor connecting cables and motor insulation will lead to a shorter insulation lifetime. If any of the voltage transient peaks exceed the insulation corona discharge level (partial discharge level), the insulation will gradually degrade with each voltage pulse. When it has been sufficiently degraded, it will then fail.Most new “inverter rated” motors have triple layer insulation which has a 1600 to 2000 volt partial discharge level. This will make them suitable to withstand the double voltage peak transient from a 600 volt inverter. It is wise to make sure of this fact, since a “standard” induction motor will only withstand about 1200 volts. Use of a standard motor in this application would shorten its life drastically. This can sometimes be as little as a matter of hours."

Jan 1, 2000

By G. Itoh, S. Fukasawa

The Al-Zn-Mg alloys have been known to be susceptible to stress corrosion cracking (SCC), which is based on intergranular cracking arisen from hydrogen embrittlement (HE). The mechanism of HE has not been fully understood yet. In order to elucidate the mechanism of HE, we need to investigate the behavior of hydrogen in the alloys. In this paper, behavior of hydrogen in an Al-5.8%Zn-2.4Mg alloy was investigated by means of hydrogen microprint technique, a method to visualize location of hydrogen emission from specimen surface as silver particles. One side of the tensile test pieces was electrolytically polished and then covered with photographic emulsion. Hydrogen was pre-introduced into the test pieces from opposite side by cathodic electrolytic charging for 30min. Then, the test pieces were stretched with continuing the charging. After that, the specimen was fixed, rinsed, dried and observed with a scanning electron microscope. As a result, silver particles were observed on some grain boundaries.

Jan 1, 2015

By Collin Bartlett, H. Storch

"Modern metallurgical processes operating with oxygen enriched air, such as the Outotec Flash Smelter and Flash Converter, generate very concentrated SO2 off-gas, which in combination with Outotec sulphuric acid plant technology allows the production of high pressure steam to be used for power generation. Outotec combines well proven technology of sulphur burning plants for this purpose with metallurgical plants.The application of Outotec’s proven LURECTM process enables processing of SO2 gas of up to 25 vol.-%. This process maximizes the energy recovery from the SO2 oxidation at a suitable high temperature level which can be turned into high pressure steam. The application of the Outotec HEROSTM heat recovery system enables the generation of low pressure steam from the absorption energy released at the intermediate absorption step. Additionally, energy is also recovered in the acid coolers for boiler feedwater pre-heating.The concept of integration of high and low pressure steam in combination with the pressurized operation of the boiler feedwater deaerator, thus heating up the boiler feed water to temperatures around 160…170°C, enables indirect transfer of low pressure steam (for deaerator operation) into more valuable high pressure steam, which improves the degree of heat recovery. This is the characteristic of Outotec’s HEROS+TM process.The increased generation of high pressure steam will in turn enable the generation of more electricity when compared to a standard traditional sulphuric acid process."

Jan 1, 2014

By Derek H. C. Wilton

"The Cape Ray Fault Zone of southwestern Newfoundland contains two notable electrum/ base metal sulphide quartz vein lode occurrences hosted by two contrasting lithological units, viz. a graphite schist horizon and a granite. The two occurrences, although in proximity, are not in direct contact, but, based on geochronological, geochemical and isotopic evidence, they were apparently deposited from hydrothermal fluids generated as a vapour phase from the magmatic progenitor of the Windowglass Hill granite.This paper provides further evidence, from REE and background A u and Ag data, for the magmatic origin of the hydrothermal fluids. Wall rocks to the electrum-bearing quartz veins in both the schists and granite have experienced a LREE depletion probably due to leaching by Cl-bearing solutions. Gold and silver contents are typically low in all rock types but there is a slight elevation in gold concentrations in those units in contact with the Window glass Hill granite. The granite also has the relatively highest gold and silver contents of any unit in the region.IntroductionThis paper presents the evidence from rare earth element (REE) and gold/silver concentration data for the magmatic origin of hydrothermal fluids responsible for deposition of the Cape Ray electrum deposits of southwestern Newfoundland. The two deposits occur in the Cape Ray Fault Zone (Fig. I) within the Windsor Point Group and Window glass Hill granite. The larger occurrence is called the Main Shear Showing and consists of a deformed quartz vein horizon, which extends for - 6 km, within the late Devonian Windsor Point Group. This unit is an intermixed ignimbrite and mafic tuff sequence with associated schists (metasediments) and gabbros. The host rocks to the mineralized quartz veins are interleaved graphite, chlorite and sericite schists. Basal ignimbrites within the Windsor Point Group have been dated, by Rb/Sr isotopic methods, at 377 ±21 Ma (Wilton, 1983a). The basal ignimbrites also have enriched REE patterns, an elevated initial Sr ratio (0.709) and a peraluminous-siliceous nature which suggest they resulted from the partial melting of continental crust (Wilton, 1984)."

Jan 1, 1985

By N. Shi, T. G. Joseph

ABSTRACT: A prototype test dipper (at 1/20th volume and a geometric operating scale of 2.85) was compared during field trials against a conventional dipper with the same tare weight using the same test shovel. Both dippers followed similar dig trajectories, invoked by the shovel operator. A Microsoft® Visual Basic-embedded spreadsheet was used to interpret qualitative visual and quantitative numerical loading data collected on the hoist and crowd dig response. Overall the concept dipper, even with a 50% greater capacity, provided indications of a smoother dig cycle with lower peak hoist loading events and a lower energy per unit excavated.

Jan 1, 2011

By R. K. Jonas

Many leading copper and other mineral processors have rapidly adopted advanced controls in last 5-10 years. Almost 600 multivariable predictive controls have been installed in mineral processing, and almost 50% of those are in copper concentrator plants. In most cases, mineral processors rely on 3rd party support to implement these advanced technologies. One challenge facing advanced control user is the selection providers and services for these technologies. The trend has been towards the use of multivariable predictive control and use of technology provider’s services. This paper will discuss status of advanced control, and the merging trends in the mining industry. A review will be presented of how advanced control is being applied in the mining industry over the last decade, and how user challenges are being overcome. Next the emerging uses of multivariable predictive control (such as multi/inter-unit optimization), focusing on the latest trends in concentrator plants. Finally, a review will be made of emerging technology advances in the that can be advantageous to mineral processors. INTRODUCTION Review of advanced control in mineral processing Advanced controls are serving an increasing role to improve processing plant operations and profitability. As advanced control is being installed into more mining processing plants such as copper concentrators, many of these plants are concerned about the selection technologies and vendors to support the installation and maintenance of these controls. In a study by Jonas and Craw (2011), they found that most new users have not had prior experience with advanced controls. It is the author’s experience of almost 30 years in advanced controls that most mineral processers considering advanced controls can benefit from better understanding of the technologies and their support requirements.

Jan 1, 2019

"The South African Mineral Resource Committee (SAMREC), a Working Group of the SAMREC/SAMVAL Committee (SSC), under the joint auspices of the Southern African Institute of Mining and Metallurgy (SAIMM) and the Geological Society of South Africa (GSSA) developed the SAMREC Code. The Code sets out minimum standards, recommendations and guidelines for public reporting of exploration results, mineral resources and mineral reserves in South Africa. It is applicable to the reporting of all styles of solid mineralization or economic deposit. However, certain commodities, namely coal and diamonds, have specific additional reporting requirements. The Code does not apply to oil, gas or water."

Jan 1, 2003

By H. Kalsi

"IntroductionRoyal Oak Mines Inc. is currently operating the Parnour No.1 mine located 10.5 miles east of Tinunins, adjacent to Highway No. 101. The operation produces gold ore at a rate of 3300 tpd. A variety of mining methods including bulk open stopes with ITH drilling, narrow vein panel, longhole and open pits contribute to produce 1.2 rnillion ore tons annually. The milling process requires water at an average rate of 1 rnillion gallons per day (700 U.S. gpm). The Pamour No.1 mine has historically had two major problems with regard to water control. The flfSt is the underground pumping system&apos;s inability to handle excess inflows of water generated from spring thaws. When the thaw takes place over a short period of time, large inflows of water are created which quickly migrate underground and sometimes result in the loss of the lower loading pocket. During the spring runoff the pumps at Parnour No.1 work continuously for 24 hours at a rate of 1200 U.S. gpm. The system was further taxed in 1991 when the Hoyle mine was connected to the Parnour No. 1 mine and whatever excess capacity the pumping system had for the spring runoff was taken up handling the inflow of mine water generated by the Hoyle.The second problem facing the mine was the lack of water for the mill during the severe cold winter months and dry summer months. At those periods inflows of water into the mine decline and the underground water normally pumped to the mill is severely decreased. In times of dry spells mill personnel increase the water diversion from the Three Nations Lake in order to meet water demands and maintain tonnage throughout. In essence, the mine was going through an annual ""feast or famine"" situation and a solution was needed.A number of options were considered but were narrowed down to the two most practical. The first was to modify the existing pumping system and increase its capacity in order to handle the excessive runoff during spring thaw. This involved a heavy capital expenditure and would have caused additional operating costs (i.e. increased hydro). The option chosen by the management was to divert the spring runoff into an unused section of the mine called The West End. A bulkhead placed at the 2400 level would provide an ultimate underground water storage potential of 150 million gallons. This would also cut down the load on the existing pumping system, save electric consumption in pumping and provide water storage which could be used for milling during the two dry spells. Pumping stored water from the mine could be scheduled for off peak hours to take advantage of lower power rates. To meet these objectives an underground bulkhead capable of withstanding high water pressure up to 2000 ft head (866 psi) was constructed in the spring of 1992. The bulkhead site was at the 2400 level at the Pamour No.1 mine. A major consideration was the requirement to construct a safe bulkhead and to minimize water leakage from the bulkhead.Figure 1 shows the bulkhead location."

Jan 1, 1994

By L. A. Melis, A. R. Marchbank, S. A. Webster

"Certain northern Saskatchewan uranium ores have a high content of nickel and cobalt which offer the potential for recovery as a by-product to uranium. A nickel/cobalt recovery process has been developed as a viable method of recovering a marketable concentrate from typical uranium raffinate solution.Impurities are first removed from the raffinate and the pure solution is then treated with sodium carbonate to recover a bulk nickel/cobalt carbonate precipitate for sale to a primary nickel producer. All contaminants of concern are removed to very low levels and the product is free of radioactive contamination with gamma emissions significantly below natural background. Cost estimates have shown that installation of a nickel/cobalt recovery circuit within a uranium process plant is economically feasible.The testwork that led up to the selected process is described along with recommendations for further investigations such as additional testing of hydroxide precipitation as a possible viable alternative to carbonate. The selected process is described and project economics are briefly reviewed.PROCESS TEST PROGRAMBackgroundExtensive metallurgical research has been performed over the years to develop a process for recovering uranium from the Midwest deposit in northern Saskatchewan. During the course of this research, a certain amount of information became available which suggested that recovery of nickel and cobalt from uranium raffinate could be economically feasible. It was decided to undertake a test program which would investigate methods of separating nickel and cobalt from radioactive and other metal contamination to permit production of a saleable product.Available technology suggested that three general approaches could be taken to recover nickel and cobalt. The first and simplest approach would be to selectively precipitate the impurities of concern, primarily arsenic, iron and radium, and then recover a bulk concentrate from the purified raffinate. The second approach would be to purify the raffinate and then remove cobalt from solution by solvent extraction producing pure nickel and cobalt solutions for further treatment. The third approach would be to precipitate all metals from solution and then selectively re-dissolve nickel and cobalt in ammoniac solution which would be further treated by solvent extraction for nickel recovery, leaving cobalt for further treatment."

Jan 1, 1993

By Jeremy G. Berg, James B. Mulligan

"There is a very small fraction of wireless experts in the world with experience in underground installations and an even smaller fraction that have experience specific to building mine shafts. This is why in 2009, Redpath created its own system to meet the demands specific to shaft construction. Today, after a dozen shaft installations and several design iterations, Redpath has the expertise and experience required to implement a proper wireless system in any shaft configuration.This document will explain multiple proven wireless communication designs optimized for shaft construction and suitable for permanent use. This includes line of sight installations up to 1200m, short range mesh networks, and the latest patent pending Integrated Leaky Feeder Mesh Network. Additionally, this document will explore the lessons that Redpath learned in its effort to interconnect the people and tools needed to build a mine shaft.INTRODUCTIONAfter a decade of research, several design iterations and a dozen application examples, Redpath has resolved two wireless network architectures to best serve mine shaft construction projects.The long range line-of-sight (LOS) wireless network is the most cost effective and easiest to install, but requires an unobstructed line of sight between the working area and the shaft collar. As such, long range LOS is best suited for ventilation shafts or during the first phase of shaft sinking, before the shaft is equipped.Alternatively, a mesh network uses radios installed at pre-determined intervals in the shaft and on each conveyance. A wireless mesh uses antennas to bridge intervals between shaft radios, whereas Redpath’s integrated leaky feeder mesh network (patent pending) bridges these intervals with radiating cable, commonly referred to as a “leaky feeder” cable. Both of these mesh configurations can provide continuous reception for hoist conveyances travelling in shafts without line-of-sight, making them ideal for shaft equipping and even permanent installations in both mine shafts and lateral drifts.BACKGROUNDHoist operators receive operating commands using what are commonly referred to as “bell signals.” These instructions are delivered in a series of coded pulses on a spring returned pull cord or push button that is typically hardwired back to the hoist operator’s control room from one of many locations in the mine shaft. During the construction phase of a traditional mine shaft, a worker riding inside the sinking bucket would have to reach out to a pull cord installed on the shaft wall to send a stop command to the hoist operator. Today, Redpath’s modern shaft sinking projects use fully enclosed personnel carriers to protect the workers riding inside, specifically preventing workers from reaching out into the shaft while the hoist is in motion. The enforcement of this safety feature on all shaft projects in 2008 forced the engineering group at Redpath to find a suitable wireless solution for hoist communication to facilitate shaft construction.THE IDEAL COMMUNICATION SYSTEM FOR MINE SHAFT CONSTRUCTIONIdeally, the shaft communication system should not transform the tools to which the miners have grown accustomed. It should support the push-to-talk functionality of traditional VHF handsets and the standard belling system that has been used for decades. Additionally, it should be able to support a vendor independent framework upon which new devices and features can be added. The following paragraphs summarize some of the important requirements Redpath has identified.Support for voice transmission: Low latency is critical to prevent jitter during voice transmissions. The system must be compatible with commercially available mobile handsets and support several simultaneous conversations with the ability to broadcast a voice message to all users on a select channel using a “push-to- talk” microphone and loudspeaker.Transmission of PLC data: Low latency is required to"

Jan 1, 2019

By H. H. Gardner

INTRODUCTION THE problem of mechanization is one of the most vital in the minds of Alberta coal operators today. In these times of constantly increasing operating costs, any way of decreasing the cost of a ton of coal must be explored to the limit. There seems no better field for such effort than the successful application of power to the mining and loading of coal. We are fortunate in having neighbours to the south who have made .remarkable progress in recent times along these lines. Higher tonnages per man have resulted in higher wages to the employee and lower cost to the employer. It might seem that our problems could be solved merely by imitating our neighbours. Unfortunately, neither practice nor experience substantiate this conclusion. It is with the purpose of reviewing our accomplishments, as compared with practice in the United States, and at the request of the Prgoramme Committee for this meeting, that this paper is written. The Committee believes that such a general discussion and comparison may well lead to further advances in our mining methods. SUMMARY OF PRACTICE IN THE UNITED STATES A visit to the highly mechanized coal mines of the United States is always most instructive and encouraging.

Jan 1, 1951

By M. L. Haider

Introduction I Appreciate very much the opportunity of discussing with you tonight oil developments in western Canada. These developments are of importance to all of us, first because of their great economic significance to all of Canada, and second because of the location of the new oilfields. Situated as they are in the west and northwest, they are of considerable strategic value from the standpoint of continental defence. The story of oil development in Canada covers a span of almost a century, during which time success in finding reserves of petroleum was barely sufficient to maintain interest in continuing the search. Finally, in 1947, a well of the first importance was completed in Alberta and, judging by discoveries made since then, it appears that Canada, at long last, is to become an important producer of petroleum.

Jan 1, 1950

By Dan Currie, Tom Lamb, J. Coady Marsh, Gary Landry

"This paper describes the Cape Breton Development Corporation&apos;s experience with the Lovat M-300 tunnel-boring machine at the Donkin-Morien Mine. Between January 3 and December 21, 1984, the 7.6 m (25 It) diameter TBM advanced 3350 m (10 990 ft) . The authors will describe experiences with the machine and highlight the implications of tunnelling machines to underground coal mine development in Canada. IntroductionThe Cape Breton Development Corporation (CBDC) has recently completed the drivage of a 7.6 m (25 ft) diameter tunnel, 3.5 km (2.2 miles) in length , to access the Harbour Coal Seam at the Donkin-Morien Project. The tunnel was successfully driven with the first Canadian rock tunnel-boring machine (RTBM or TBM), designed and built by Lovat Tunnel Equipment, Inc. The initial mine development consists of the drivage of two tunnels to the first major coal seam. Future plans are proposed for the development of a 4 million tonne-per-year mine (Marsh et al., 1983, Gillman, 1982), which will require the drivage of a further two tunnels and could access up to four coal seams. The tunnel cross-sectional areas were designed to provide sufficient ventilation area and access for a production of 4 million tonnes per year."

Jan 1, 1986