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By David Thomas, Charles Harper, Brian Watters

The Star-Waddy Lakes area lies withjn the northeasterly-trending early- to mjd-Proterozoic volcanoseilimentary-pl utoruc belt referred to as the La Range Domllin. In the area investigated the domajn is composed of the Central Metavolcaruc Belt which is bordered by metasedimentary belts of the Crew Lake and MacLean Lake Belts to the northwest and southeast respectively. The boundaries between the Central Metavolcanic Belt and the flanking belts are generally marked by prominent zones of shearing. The volcanosed imentary succession is intruded by a variety of ultramafic to felsic plutons which, on the basis of lithology, field relations and geochronology, can be broadly subdivided into three groups or episodes. These are: a) an 'early' (ea. 1866 Ma), possibly subvolcanic, episode marked by composite intrusions ranging from gabbro-diorite to granite, b) an 'intermediate' (ea. 1854 Ma) plutonic event distinguished by more homogeneous felsic intru ions ; and c) a 'later' (ea. 1835 Ma) event characterized by leucocratic quartz-rich grani te intrusions. The La Range Domain has undergone polyphase deformation with a strongly developed northeast-trending structural grain. Large scale folding is manjfested by large regional sy nforms, arcuate and triangular patterns associated with many of the plutons and by tight to isoclinal folds within the adjacent metasedimentary belts. Inhomogeneous strain characterizes much of the Star-Waddy Lakes area. With strain gradients being typically very steep, zones of high strain consisting of zones of extreme extensional fabrics, discrete shearing, as well as broader zones of cataclasis and structural slicing, are often juxtaposed with areas of relatively minimal deformation . Dilation structures tend to favour these zones of highly contrasting strain. Late, brittle fractures, faults and shear zones are widespread and appear to be particularly important as loci for gold mineralization. Metan1orphic mineral assemblages indicate that upper greenschist to middle amphibolite facies conditions were attained. Geological and geochenucal evidence indicates that the Central Metavolcanic Belt evolved in an island arc environment. Metavolcanic rocks from both the Waddy and Star Lakes areas display similar characteristics on variation diagrams (e.g. AFM and the Jensen cation plot) in that the dominant trend is calc-alkaline with some basic to intermediate types having a mildly tholeiitic character. A few samples from the southern end of Lower Waddy lake display komatiitic to basaltic-komatiitic afl'injties. The relatively immobile minor and trace elements (e.g. Ti , Zr, Nb, Y, Cr) provide reliable characterization of the metavolcanics, particularly of the basalts, which have highly distinctive trace element properties. Geochemical patterns for the basalts are similar to those for modem volcanic arc basalts. Low initial 87Sr/86Sr ratios (0.7017 - 0.7019) are consistent with a subduction-related origin for the volcanics. The major plutons have chemical properties typical of volcanic arc granites and are largely calc-alkaline in character, showing little chemical variation from the volcanics.

Jan 1, 1986

By W. R. Tyson

IT HAS BEEN KNOWN for many years that alloy steels can become brittle when tempered in the range of 350-600°C, or cooled slowly after heating to higher temperatures. The metallurgical literature reveals that blacksmiths were aware as early as 1883 that water quenching was necessary after heat treatment above 600°C to avoid brittleness. It has also been known for years that the problem is associated with trace impurities; a paper in the Journal of the Iron and Steel Institute of 1894 refers to the brittle, faceted fractures that occur in steels containing arsenic, phosphorus or sulphur. However, definitive investigation of the mechanism of embrittlement has been possible only within the last decade with the introduction of new experimental techniques to investigate surfaces, especially Auger electron spectroscopy. It is now possible to study in detail the chemistry of surfaces with a resolution of an atomic layer or two, and enormous progress has been made recently in studying the segregation of impurities to grain boundaries by exposing the boundaries by fracture inside the microscope. A clear picture of the processes occurring and their interpretation is now emerging, as was particularly clear at the recent 1977 ASM Materials Science Seminar on Interfacial Segregation held in Chicago in October. Recent research in this area has pointed the way for commercial exploitation of this new knowledge and experimental technology. It is the purpose of this article to trace progress in understanding temper embrittlement and to indicate other areas where control of interfacial segregation and its effects can be important in metallurgical applications.

Jan 1, 1978

By F. J. Hrach, S. A. Gasiorowski, J. D. Bittner

"Separation Technologies, LLC (ST) has developed a processing system based on triboelectric charging and electrostatic separation that provides the mineral processing industry a means to beneficiate fine materials with an entirely dry technology. In contrast to the other available electrostatic separation processes that are typically limited to particles greater than 75 µm in size, the ST belt separator is ideally suited for separation of very fine (<1 µm) to moderately coarse (500 µm) materials with very high throughputs.. The technology has been also successfully applied to the beneficiation of a variety of minerals including calcium carbonates, talc, and potash. TECHNOLOGY OVERVIEWThe ST separator utilizes electrical charge differences between materials produced by surface contact or triboelectric charging. When two materials are in contact, material with a higher affinity for electrons gains electrons and thus charges negative, while material with lower electron affinity charges positive. This contact exchange of charge is universally observed for all materials, at times causing electrostatic nuisances that are a problem in some industries. Electron affinity is dependent on the chemical composition of the particle surface and will result in substantial differential charging of materials in a mixture of discrete particles of different composition.In the ST separator (Figures 1 and 2), material is fed into the thin gap 0.9 – 1.5 cm (0.35 -0.6 in.) between two parallel planar electrodes. The particles are triboelectrically charged by interparticle contact. For example, in the case of coal combustion fly ash, a mixture of carbon particles and mineral particles, the positively charged carbon and the negatively charged mineral are attracted to opposite electrodes. The particles are then swept up by a continuous moving open-mesh belt and conveyed in opposite directions. The belt moves the particles adjacent to each electrode toward opposite ends of the separator. The electric field need only move the particles a tiny fraction of a centimeter to move a particle from a left-moving to a right-moving stream. The counter current flow of the separating particles and continual triboelectric charging by carbon-mineral collisions provides for a multistage separation and results in excellent purity and recovery in a single-pass unit. The high belt speed also enables very high throughputs, up to 40 tonnes per hour on a single separator. By controlling various process parameters, such as belt speed, feed point, electrode gap and feed rate, the ST process produces low carbon fly ash at carbon contents of 2 % ± 0.5% from feed fly ashes ranging in carbon from 4% to over 30%."

Jan 1, 2012

By M. G. Manzone

Approximately two-thirds of the annual 210,000 tons at copper refined by AMAX Inc. at the United States Metals Refining Company in Carteret, New Jersey, comes from a wide variety of copper scrap ranging from low-grade smelter scrap to wirebar-grade material. The equipment and methods used to effect such large-scale metal recycling in an urban area and the measures taken to collect and recover metal values from smelter and refinery byproducts while protecting the environment from pollution are described and discussed.

Jan 1, 1977

By R. Viljoen, K. Manns

"The mining industry instinctively follows rule-of-thumb design velocities often based on very simplistic theoretical “economic velocity” optimization calculations to determine airway sizes. Although these are important building blocks in ventilation planning it should be recognized that mines are far more complex and various, often opposing factors, are at play. Therefore, it is important that each ventilation situation be analyzed on a case-by-case basis to determine the best-fit solution for an operation. The ventilation design process should not necessarily be constrained by theoretical optimal economic velocities that become rules-of-thumb. In some cases, this could lead to unrealistic infrastructure requirements and exorbitant capital expenditure. This type of design often lacks corporate support leading to a scenario where no ventilation upgrades are implemented. Economic velocities typically consider the cost of power, development costs and operational risk. These typical rules-of-thumb work reasonably well as a starting off point when considering feasibility of greenfield projects. For established mines that are looking at expansion these rules may not be appropriate due to capital expenditure constraints or geotechnical ground conditions. The theoretical optimum should be reviewed in the case of an established mine where existing infrastructure could perhaps be maximized. For example, the geotechnical risk of large diameter raises at depth may require multiple small diameter raise to maintain the theoretical economic velocity. If a mine has a life of less than 5 years, then the cost of power is an insignificant proportion of the total owning cost. For these mines, operating the ventilation raises at an increased velocity to avoid a complicated and expensive capital upgrade might be the more appropriate option, even though it opposes the traditional rules-of-thumb. Mines which are capital constrained may be better off accepting a higher operating cost for the interim or settle for minor infrastructure upgrades rather than run the risk of the entire ventilation upgrade not being approved at all. This paper explores a number of examples derived from case studies undertaken by the authors for several deep mechanized mining projects in Australasia. The examples explore conditions under which higher than the economic norm would be applicable."

Jan 1, 2019

By C. R. Tang

The respirable dust real-time monitoring equipment export information is complex, and electromagnetic wave wireless transmission is affected largely under mine conditions. The respirable dust concentration information transmission method based on led light equipment is proposed. The respirable dust concentration data of the individual real-time monitoring equipment is encoded to fit the system transmission; the encoded signal is modulated onto the LED mine lamp; the light signal is transmitted by the spatial channel; the signal is received by the receiver to the photoelectric conversion to restore the respirable dust concentration data for subsequent processing. Simulation and verification experiments showed that the respirable dust concentration information transmission method based on led light equipment can achieve the LED miners? lamps visible light wireless data transmission.

Aug 1, 2013

According to the principle of similarity, the physical and chemical configurations of a system can be defined by ratios of magnitudes within the system and do not de-pend on the size or nature of units of measurement. In the present work, the similarity principle was utilized in evaluating the reducibility of various iron ores in a rotary batch furnace under optimum operating conditions. It was then used successfully to extrapolate the results, first to the operation of a 20-ft. pilot-plant kiln and then to an industrial-size 80-ft. kiln. By means of this systematic analysis of kiln operation, it was possible to increase the production capacity of the kiln considerably. T HE kilns used by the Strategic-Udy process for the partial reduction of iron ores are, in most aspects, similar to conventional calcining kilns. Iron ore is fed continuously in the upper (feed) end of the kiln and, as the latter rotates

Jan 1, 1964

By Denis Yaychuk, Gary Billingsley

The economic eva luation of a mineral property or mining venture should include the quantification of ri k as part of the analy is. The re ults of such an analysis provide the decision-makers not only with the most likely financial outcome and the probability of achieving that or any other outcome. but al o with a ranki ng of the relative impact of all the ri sk factors. These type of resu lts offer more complete information for investment and technical deci ions than the traditional cash flow/ ensitivity analysis. In addi tion. by attempting to quantify ri sk. the personnel providing the va ri able input are forced to take a much clo e r look at the data involved, and are fo rced to work together. the reby increa ing substantially the awa reness of the impact their work and others· work has on th e outcome of the analysis.

Jan 1, 1986

By Garnet T. Page

"ABSTRACTThese societies •can help in such aspects of a vocation.al guidance program in secondary schools as: provide vocational and technical information, and assist with vocational exploration, such .as plant visits, films, etc. -as .an aid to the student in making a self-inventory. Evidence is increasing that employers' needs for engineers and scientists will not be adequately met in the future. Therefore, the E.I.C., C.I.M., .and C.I:C. recently revised and extended the activities of the Canadian Counselling Committee on Engineering and Science. This co-•operative .action is to be integrated with the educational system, nationally .and locally, and with provincial associations •of engineers and other groups interested in the provision of vocational information in engineering and science.DEFINITIONTHE scientific treatment of any subject requires consistent use of carefully defined terms. The National Vocational Guidance Association of the United States studied the problem of the definition of vocational guidance for .about 16 years, and in 1937 finally arrived at:""Vocational guidance is the pro-cess of assisting the individual to choose an occupation, prepare for it, enter upon and progress in it. It is concerned primarily with helping individuals make decisions and choices involved in planning a future and building a career -decisions and choices necessary in effecting satisfactory vocational adjustment.""RANGEAs a school enterprise, vocational guidance begins at that point in the individual's life when he finds it necessary to make choices that have a definite significance for his future vocation."

Jan 1, 1952

By D H. Sharp

The Quebec Cartier Mining Company produces iron concentrate for twelve months of the year from Port Cartier. This J>Ort is designed to handle ship varying in size from 3,000 to 100,000 d.w.t., requiring 50 feet of water at low tide. The harbour was built on shore for reasons of economy and layout, after considering many more conventional offshore designs. It provides for heavy oil bunkering, tanker off-loading, a heavy lift derrick and freight handling, besides ship loading and mooring. The weather for the previous fifty years was studied to enable wind and wave conditions to be accurately assessed for design purposes, and to determine probable lost time due to adverse weather conditions through-out the year. The first ship to be loaded was 60,000 d.w.t.; the second, 20,000 d.w.t. The latter entered the harbour after dark, under its own power, following a tug through the partly dredged narrow entrance. Large ships use tug assistance. Ships may leave the loading berth with the other berths occupied.

Jan 1, 1963

By D. D. Liu

This paper proposes a charge induction dust measurement method based on detrended fluctuation analysis (DFA) for use in coal mine environments, based upon electrostatic interference, dust properties, wind speed, particle size, moisture content and other factors. In this methods, sequence x(t) is first obtained through a dust concentration sensing probe, and then the cumulative deviation y(t) is calculated, and y(t) is divided into same lengths. Secondly, a first-order linear fit is used for data of each interval, and mean-square deviation filtered DFA was calculated for each interval. Finally, the dust mass concentration of the corresponding time is obtain by supplemented calibration coefficient and fitted the data point which is the mean and square root for all lengths of interval. Simulation and verification experiments showed that the charge induction dust measurement method based on DFA can reduce coal mine electrostatic interference effects with high accuracy. The design has been successfully applied to select areas.

Aug 1, 2013

By J. B. Morrow

Methods of Coal Preparation Fundamentally, the object of coal preparation is to increase, economically, the value of a fuel by making it more suitable to the uses of the consumer. This can be accomplished in three major ways: 1.Screening or sizing 2.-Mixrng or blending 3.-Cleaning By combinations of any or all of these methods we can prepare coal to meet standard specifications-a process of standardization which is the more desirable the more nearly it approaches the unvarying quality of packaged goods, where the package you buy today and tomorrow is the same as that you bought yesterday. It should be noted that it is readily possible to get good cleaning and still have poor preparation because of faulty screening and mixing, and, on the other hand, it is possible to get a passable grade of cleaning, combined with good screening and mixing facilities.

Jan 1, 1931

By C. W. Jr. Waterman

INTRODUCTION MY SUBJECT is one which would require several speakers and many hours of time for adequate presentation in all its many facets. Because of the widely varying market requirements and coal seams mined, the coal industry of the United States bas of necessity employed many types of preparation facilities to satisfy its needs. Predominance of Baum-type jigs, however, bas marked the mechanical cleaning installations since the early thirties, and these machines continue to hold the lead. CLEANING As a matter of record we find that, at the end of 1948, we had 480 mechanical cleaning plants in operation. Of these, 19 used air cleaners only,?400 used water washers only, . and 61 used dry and wet washers in combination . Due to the increased use of spray water underground on cutting and mechanical mining equipment, there has in recent years been a marked downward trend in dry cleaning installations. In fact, the moisture in dry-cleaned fines has been increased to such an extent by spraying that recent dry cleaning installations have incorporated thermal drying ahead of the dry cleaning units in an effort to overcome the varying and increasingly higher moisture percentages in their raw coal feeds. While on the subject of dry cleaning, it might be well to bring to your attention one of our most recent developments in this art. I refer to the McNally-Brusset vacuum jig.

Jan 1, 1951

By Pierre Sauvé, Alex Makila

"The Camflo stock of porphyritic quartz syenite is an irregular pipe-like body 200 metres in diameter injected along the axial plane of an E-W trending F2 fold, near the contact between the. Kewagama and Malartic groups. The stock plunges 55° to the NE, almost parallel to the fold axis. The stock, exhibiting pervasive, weak cataclasis with numerous, locally auriferous quartz veinlets, is cut by minor faults striking WNW and dipping about 45°NE.Two types of gold ore are distinguished at Camflo: ""porphyry"" ore and ""fault zone"" ore. ""Porphyry"" ore, accounting for 90% of the gold produced, forms wide zones within the stock. The zones are irregular in shape but tend to be oriented E-W in plan view (on a horizontal plane) and are elongated paraliel to the plunge of the stock. These zones are more abundant in the northern part of the stock. Differences between ore and barren porphyry are not obvious. ""Fault zone"" ore occurs outside the stock along minor faults, particularly in differentiated sills offer rodiorite and felsic granophyre. Gold grade is roughly proportional to the pyrite content which in turns depends in part on the original magnetite content of the host rock. Although both types of ore show some correlation between Au and S, the Au/S ratio is considerably higher in porphyry ore.The bulk of the gold is in quartz syenite and in felsic granophyre, the most brittle lithologies at the mine. Presumably, the vertically continuous, pipe-like stock, made up of shattered rock, provided the main channelway for the ascending mineralizing solutions."

Jan 1, 1990

By A. Brown

THIS P APER has been pre-pared as a progress report on Mines Branch investigations into problems of ground stress in certain co al mines of Western Canada. As such, it should be considered as a companion report to the one ( 1) presented to the Mining Society of Nova Scotia in 1956 and which dealt with similar investigations in the coal mines of Eastern Canada. For the past 50 years, dynamic incidents in the form of &apos;bumps&apos; and &apos;outbursts&apos; have been occurring in the coal mines of the Inner Foot-hills belt of tl1e Canadian Cordillera. As these phenomena generally become more frequent with in-creased thickness of overburden, a limiting depth of mining of 2,500 feet has been set (2) for estimating recoverable reserves of coal. If such a view were accepted, from a long-term viewpoint very large resources of coking-grade ?coal -in a part of the continent deficient in such coals -would not be available to the nation. The terrain in which these in-6dents take place may be described in geological terms as being dominated by pronounced structure in strata ?consisting of a large proportion of highly indurated rocks. The Geological Survey of Canada has co-operated by carrying out structural studies (3) at the mines, supplemented lithological by stratigraphic observations.

Jan 1, 1958

By Arthur M. Whiteside

Discussion of the laws bearing upon the economics of mining in this province at once resolves itself under three headings: (a) The rights and obligations of holders of mineral bearing lands; (b) Taxation of mines; (c) Regulation of methods adopted in financing mining operations. Titles: The law relating to titles is contained in the Mineral Act, Placer Mining Act and Coal Mines Prospecting Act. Origin: Mining laws in force in this province and elsewhere on the continent had their origin in the rule-of-thumb regulations adopted by prospectors themselves, when, far from the centres of civilization and the seats of the courts of justice, they found it necessary, for mutual protection, to fix the conditions of possession by right of location, and to prescribe the duties to be performed in order to enable the individual to maintain his ground against all comers. These regulations have been codified and added to by legislatures, until we find adequate protection and safeguard to property in the laws of this province.

Jan 1, 1924

By A. Aftabi

Abstract-To evaluate geochemical aspects of sheared zones, 35 samples of granitoid rocks from an area of shearing >5 km2 at Derehamzeh, Iran were studied geochemically. Relatively unaltered samples within the shear-zone area average 38 ppm Cu, 1.45 ppm Mo, 4.6 ppb Au, 0.21 ppm Ag, <1 ppm Re, 46 ppm Zn, 28.5 ppm Pb, and 0.34% S. Bleached, hydrothermally-altered samples are anomalous in Cu (>896 ppm), Au(>59.5 ppb), Ag(>24.4 ppm), Re(>1.28 ppm), Zn (>164 ppm), Pb (>218 ppm), and S(>0.9%). Some samples from bleached sheared zones that are highly anomalous in Cu (5000 ppm), Mo(23 ppm), Ag(74 ppm), and Au(200 ppb) are characterized by a typical sericitic alteration assemblage consisting of sericite, pyrite, chalcopyrite, and granular quartz. The main anomalous zone extends over about 0.4 km2 in the southern part of the area. The strong Cu- Mo-Au-Ag association in the sericitic shear zones suggests a possible relationship to porphyry copper mineralization, similar to that found in northern Chile. Further studies on drill-core samples in the southern sericitized shear zones are required to determine if more extensive porphyry-type sulfide mineralization is present.

Jan 1, 1997

By A. Aftabi

To evaluate geochemical aspects of sheared zones, 35 samples of granitoid rocks from an area of shearing >5 km2at Derehamzeh, Iran were studied geochemically. Relatively unaltered samples within the shear-zone area average 38 ppm Cu, 1.45 ppm Mo, 4.6 ppb Au, 0.21 ppm Ag, <1ppm Re, 46 ppm Zn, 28.5 ppm Pb, and 0.34% S. Bleached, hydrothermally-altered samples areanomalous in Cu (>896 ppm), Au(>59.5 ppb), Ag(>24.4 ppm), Re(>1.28 ppm), Zn (>164 ppm), Pb(>218 ppm), and S(>0.9%). Some samples from bleached sheared zones that are highly anomalous in Cu (5000 ppm), Mo(23 ppm), Ag(74 ppm), and Au(200 ppb) are characterized by a typical sericitic alteration assemblage consisting of sericite, pyrite, chalcopyrite, and granular quartz. The main anomalous zone extends over about 0.4 km2in the southern part of the area. The strong Cu-Mo-Au-Ag association in the sericitic shear zones suggests a possible relationship to porphyry cop-per mineralization, similar to that found in northern Chile. Further studies on drill-core samples in the southern sericitized shear zones are required to determine if more extensive porphyry-type sul?de mineralization is present.

Jan 1, 1997

By C. D. Williams

The following paper deals with some of the aspects of the law as it relates to the oil and gas industry in the Province of Alberta, but it should be stated here that consideration of this large subject will be confined to discussion of only those laws, rules, and regulations which affect actual exploratory operations. The paper will not touch on those branches of the law which deal with such matters as income tax, customs, and other kind red subjects which are of a highly technical nature and which are more properly the field of the specialist. Generally speaking, any system of law consists of certain major components. There must be, firstly, a national authority capable of ensuring the existence of the state itself and of maintaining the stability and continuity of its institutions; secondly, a philosophy of government covering the relationship of the state to the individual and of the individuals to one another; thirdly, a body of law to effect the purposes of the philosophical principles; and, fourthly, a judiciary to arbitrate any disputes that may arise from such relationships. All of these components and the system itself are, of course, subject to a varying degree of modification with the changing times and with the influence upon them of other systems of law. Now. while it is true to say that all systems of law comprise these similar basic features, it is apparent that the end result of any two systems of law in their impact upon the individual may be quite different.

Jan 1, 1951

By A. Bowles

The process of accumulative roll bonding (ARB) has been applied to wrought magnesium alloy AZ31. Accumulative roll bonding results in severe plastic deformation of sheet material. In AZ31, this process leads to the refinement of the microstructure by dynamic recrystallization. The refinement of the microstructure results in an improvement in mechanical properties with potential for producing materials for superplastic forming. In this work AZ31 was bonded with up to 64 layers and the potential of roll cladding with aluminium was also investigated. The development of microstructure and the mechanical properties are reported here.

Jan 1, 2006