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By D. Moronkeji, R. Maharidge, D. A. Curry, B. J. Davis, U. Prasad, J. Franquet

"Proper shale characterization is crucial in shale gas drilling, exploration, completion and production. Unlike porous sandstone and carbonate reservoirs, the challenge with shales comes from their micro- to nano-darcy permeability ranges and the anisotropy of their mechanical and hydraulic properties. Most porosity-dependent logs are not sensitive enough to capture the true behavior of shales. Consequently, mineralogy and other strength and stiffness-related properties must be determined to characterize magnitudes and variances in shale mechanical and flow properties. In addition, these properties must pass quality assurance/quality control (QA/QC) practices to give confidence in their use in subsequent log calibrations, during geomechanical modeling, or in fracture design models. This paper presents a technique to integrate shale properties that are measured by various methods, and a methodology to perform QA/QC on the data before application.Shale properties originate from various sources, including downhole and laboratory measurements. Physical samples for laboratory testing are usually limited to a few depths. Lab tests are often costly, and replicating in-situ conditions can be difficult or impossible. In addition, results frequently show wide scatter, reflecting inherent depth variability and lateral heterogeneity. Wireline logs provide nearcontinuous data, but rarely yield direct measurements of rock strength properties. Although geomechanical and fracture models use log data, calibrating it with reliable and previously verified lab-measured properties is important. This paper presents a process to perform QA/QC on lab-measured data using various crossplots.Ten mechanical, microstructural and physical properties are graphically displayed to visually characterize shale strength behavior in ambient and in-situ conditions, whether measured or modeled statically or dynamically. These properties are often sourced from different departments. The properties are integrated but are individually subject to the previously mentioned uncertainties. Pairs of property values are crossplotted and compared with correlations from the literature or previously established with qualified data from related formations. Conformance with these correlations gives confidence in the data, whereas outliers are flagged as questionable. Repeating the process with questionable data crossplotted against other parameters for the same depth highlights the property with the greatest uncertainty. The determination of its value is investigated to locate the source of the inconsistency and establish a more reliable value. Where this is not possible, the user has a rational basis for rejecting that property value."

Jan 1, 2015

By J. A. Cox, R. S. Mattson

"One of the main problems encountered in employing sublevel caving is the inherent high dilution factor. The operating results at Granduc illustrate that this dilution can be closely controlled and satisfactory recoveries achieved, in base metal ores grading less than 2.0% copper equivalent, by using an assay grade control system based on the fundamental draw characteristics. The history of draw control procedures employed since the start of operations provides an effective comparison between this system and one based mainly on tonnage. The transverse and longitudinal sublevel caving mining methods are described and it is shown how improvements in design layout, operating practice and draw control in narrow complex ore zones (12-foot minimum width) have raised the operating performance of the longitudinal system to a satisfactory level."

Jan 1, 1973

By C. J. Sullivan

"The outlook for supplying the world's metal needs in the next twenty-five years is good, although in several cases basic costs are likely to increase with rising demand. Metal prices calculated at a constant dollar from 1900 to the present show that for nickel, copper, silver, lead, zinc and tin, prices -and presumably production costs -fell from 1900 to the early 1930s. Since then, they have generally risen, apparently reflecting some depletion in relation to demand. This tendency has been accentuated since the post-World War II adoption of managed, full-employment, growth economics, which have resulted in a sharp escalation in world demand for metals. (Abandonment of such policies, apparently now under consideration in North America, would, of course, affect the pre-dictions of this paper.) Nevertheless, metal prices generally are still below those prevailing in 1900. Exploration potential exists for disseminated ores of many metals still thought of as characteristic of lode and vein deposits. These include uranium, silver, gold, tin and nickel and, to a lesser extent, lead and zinc. Considering the discovery potential for some principal metals in relation to expected demand and prices, I would tend to rate them as follows: molybdenum, zinc, lead, uranium, silver, gold, tin, nickel and copper."

Jan 1, 1970

By J. Grignon, C. Fleming

It is possible to reproduce the performance of an operating CIP or CIL plant in the laboratory, in small scale batch kinetic tests, coupled with mathematical models that translate kinetic data into predicted steady state gold profiles across multi-stage adsorption circuits. Once the performance of the commercial plant has been mimicked by the model, the plant operating parameters can be varied systematically in the model, and the likely response of the plant to the step wise change can be determined. In this way it is possible to inexpensively optimize the operating conditions of an existing plant, with no disruption to plant operations and no economic risk to the mining company. This approach had been adopted by IAMGOLD to optimize the performance of their Rosebel CIL plant following several major expansions in mill capacity since 2004.

Jan 1, 2011

By M. M. O?Brien

THE SULLIVAN MINE The Sullivan mine of the Consolidated Mining and ? Smelting Company of Canada, Limited, is situated at Kimberley, B.C., nineteen miles from Cranbrook, a divisional point on the Crowsnest Pass branch of the Canadian Pacific railway. Production started on a small scale in 1900, and in 1914 the mine became the largest lead producer in Canada. In 1925 it was the largest single producer of lead and zinc in the world. Since operations commenced, 4,800,000 tons of ore have been produced from stopes and 170,000 tons from development. At the present time, ore is being mined at the rate of 1,100,000 tons per year, with a yield of about 200,000 lb. lead, 110,000 lb. zinc, and 4,000,000 oz. silver. The town of Kimberley is easily accessible by road as well as by rail. The altitude at Mark creek, a tributary of the St. Mary's river, is 3,700 feet. To th'e north of the creek, Sullivan hill rises to a height of 6,100 feet, and it is on the southern slope of this hill that the mine is located. Sullivan hill is in the Purcell range, which rises between the Rocky Mountain trench on the east and Kootenay lake on the west. It thus lies within what is commonly referred to as the East Kootenay district.

Jan 1, 1926

By B. R. Conard

Copper refining at Vale Canada (previously known as Inco) has been associated with Ni production. Because Cu and Ni carry risks for adverse health endpoints through inhalation exposure, it is critical that their aerosol levels, and the metallurgical processes through which they enter the air, are understood. Because certain Ni substances have been linked to respiratory cancers, it is also important to characterize the amounts and types of Ni compounds in occupational settings. This paper describes electrorefining and electrowinning operations near Sudbury, Ontario (1930–present), and gives aerosol measurements (1978–present).

Jan 1, 2014

By A. J. Monhemius

This paper reviews the history of modern iron-control processes in hydrometallurgy. Attention is paid to processes developed in the electrolytic zinc industry for removal of iron from zinc sulfate leach liquors and the problems faced by the industry in the safe disposal of the iron residues produced by these processes. Past lessons learned are projected onto current efforts to develop hydrometallurgical processes for treatment of copper sulfide concentrates. It is argued that any attempt to create a \u201chydrometallurgical copper smelter\u201d will fail, unless methods are developed that can recover iron in a form that can be directly used by the steel or pigment industries.

Jan 1, 2017

By William B. Hetherington

Communities are the foundation upon which the whole structure of society rests and upon which the nation builds its hope for the future. They are not established to serve any one particular generation, nor any one element or group, but should be erected to render a lasting service to all who are to follow. They play a very vital and important role in the lives and welfare of the people, in their industrial, business, and social relations, and in the economy of the nation, of which they are the fundamental assets. Communities and civic governments are destined to be vital factors in the national welfare in the days that are to come. Any improvement in national or world conditions must have its origin within the communities. Any attempt at solution of the community problem must give some consideration to the fundamental elements which exist in every community, and to the underlying principles, and ways of life and thought, upon which community life is based. The community is, in its essence, a number of people living and working more or less closely together, sharing common rights, privileges, conveniences, and comforts, which would be impossible for the individual to obtain for himself by his own efforts alone, or in any other way than by the mutual exchange of persona! services and resources. In this way, men have increased the returns from their labour and commerce, have raised the standard of their living, with better social, educational, and recreational facilities, and enjoy a greater personal security.

Jan 1, 1943

By R. S. Douglas

THE Granby Consolidated Mining, Smelting and Power Company, Limited, is engaged in the mining and concentrating of copper ores, and, incidentally, in the mining of coal and the production of electric power. The Company has been engaged in these various operations both on the mainland of British Columbia and on Vancouver island for the past forty-five years. This paper will attempt to cover their present operations in the Similkameen mining district of southern interior British Columbia. GENERAL CHARACTER OF THE DISTRICT The Interior Plateau in southern British Columbia ranges in elevation from 3,000 feet to 6,000 feet. In the vicinity of Princet0n, a depression in the Plateau forms a well defined basin which is floored with a series of nearly flat-lying Tertiary sediments containing some workable seams of lignite. From this basin, the upland surface rises gradually t0ward the south, from an elevation of 2,000 feet at Princet0n to 4,000 feet at Copper mountain, and 6,000 feet in the upper parts of the Similkameen basin, where it merges into the rugged and diversified t0pography of the Cascade system, with glacier inhabited peaks rising to over 9,000 feet. The valleys of Similkameen river and its tributaries are wide, having flaring sides and gentle slopes, and are separated one from another by subdued rounded spurs, of which Copper mountain is typical. The drainage of this district is taken care of by Similkameen river and its larger tributaries, such as Pasayten river, and Wolfe, Friday, and Whipsaw creeks. The name Copper mountain is applied to a gently arched, nearly flat-topped spur between the deep valley of Similkameen river to the west and the shallower valley of Wolfe creek tO the east. The mountain is appro-priately named from the number of copper deposits occurring on its sides and summit, some of which have been developed int0 an important producer, known as the Copper Mountain mine.

Jan 1, 1943

By S. Gaulocher

Gearless mill drives (GMDs) are the workhorse in the mineral processing industries, more specifically when it comes to grinding crushed ore and cement (in various production stages) in semiautogenous (SAG) mills and large ball mills. They are renowned for their excellent reliability and robustness, long lifespan, and little need for maintenance, and thus yield a low total cost of ownership (TCO). A GMD represents a major investment for a mineral processing plant, and its availability is pivotal for the grinding process. As a basic rule, shut-down periods are to be minimized, but even much more important is that unscheduled shut-downs be avoided. In this contribution, we will present a portfolio of innovative remote diagnostic that consist of the following three key components: 1. Trouble shooting is a form of corrective maintenance and is based on state-of-the art remote access technology, thus enabling highly skilled engineers to access the current sensor readings anytime and from anywhere in order to resolve urgent problems together with the GMD user. 2. Periodic maintenance reports are a form of preventive and predictive maintenance and aim at continuous improvement based on long-term historical records and analyses of multiple measured signals. These detailed reports highlight the health and operational status of the GMD and are periodically (e.g. 3 months) submitted to the customer. 3. Remote condition monitoring spans across preventive and predictive maintenance and is based on continuous recording and automatic analyses of relevant signals using advanced algorithms. The main issue is how to handle the enormous flood of data in an intelligent manner. The results of these analyses are made available to both the GMD user and supplier in real time in order to increase the availability and reliability of the GMD. In this paper, we consider various parts of the GMD, e.g. the cycloconverter, the ring motor, the auxiliary devices (e.g. cooling and lubrication systems), and also phenomena related to the mill itself (e.g. state and quantity of charge). The signal analysis techniques range from simple threshold-based analyses to complex time and frequency domain analyses. We will illustrate the benefits of the proposed approaches with some selected examples.

Jan 1, 2012

By C. R. Julian

THE large pyrites ore-bodies, the underground mining of which is to be described, are situated at Rio Tinto in the Province of Huelva in Southern Spain. The situation of the different ore-bodies with relation to one another is shown in Figure 1. It will be seen on the plan that the strike of the ore-bodies is approximately east and west. The geology of the district has been very fully described by Dr. D. Williams (1), so that for the purposes of this paper it will be sufficient to give briefly the salient features o each of the two larger ore-bodies which are being mined by underground methods at the present time. (a) San Dionisio.-This ore-body is the largest single deposit in Rio Tinto, having on its upper levels a length of 3,500 ft. On the upper levels the average width is approximately 200ft. but in places on the lower levels there is a width of 900ft. of un broken pyrites. Diamond-drill holes, without running out of ore, show the ore-body to persist to a depth of at least 1,600 ft. The ore-body in the upper part lies between slate and porphyry walls, but in depth is enclosed in porphyry walls. (b) South Lode.-Faulting is considered to be responsible for the break in the solid ore between South Lode and San Dionisio. On the upper levels, the South Lode ore-body has an unbroken length of 4,000 ft. The massive pyrites has a maximum width of 300ft. and an average of about 100 ft. Ore has been proved to a depth of 1,000 ft., at which depth the ore-body is much reduced both in length and breadth. This ore-body, to the depth at which it has been proved, lies entirely between slate and porphyry walls. The South Lode and the San Dionisio ore-bodies are mined both by open-cast and by underground methods. There is evidence that these mines have been exploited intermittently during the last 3,000 years; but, as is to be expected, no records are available of the tonnage mined prior to the time of purchase by the present company.

Jan 1, 1940

By I. I. Betcherman

INTRODUCTION A DISTILLATION process offers one of the most effective methods of refining metals. Its use is particularly attractive in the case of reactive metals which are not readily treated by pyrometallurgical or electrolytic methods. The 1ow vapour pressure of most metals severely restricts the applicability of the disti1lation process and only one or two metals may be effectively treated under atmospheric pressure at a reasonable temperature. If operations are carried out under reduced pressure several additional metals may be effectively distilled. Table I shows the vapour pressure of a number of metals together with a value of the free energy of formation of their ?oxides. Zinc and cadmium head the list and for many years? they have .been effectively refined by distillation. Sodium, magnesium, and calcium follow in descending order, and they may be distilled readily in vacuo and with difficulty at atmospheric pressure. Sodium, which is not of great metallurgical interest, is not considered. Magnesium has recently been produced in considerable tonnages by distillation methods ( 3). This paper describes the vacuum distillation of magnesium and calcium, their separation from each other, and their separation from less volatile impurities.

Jan 1, 1951

By C. M. Campbell

Canadian newspapers from coast to coast, have been, for months, denouncing those articles entitled, "The Whisper of Death," which have been appearing in the Montreal Star. I have not read these articles as the newspapers do not print them; they just denounce them or class them as jokes. Apparently they think that they are not suitable for the ordinary Canadian to read. It appears, however, that the Star has said that unless we balance our budget, and that soon, we shall be bankrupt. That seems to me like common sense, though the Victoria Times says editorially that the Star claims will "shortly find a place in the joke column". In this editorial the Times quotes with much enthusiasm from the Quebec Telegraph. "Canada," says the Telegraph, "is all right. Her natural resources are so vast that no one need worry. Her future possibilities are limitless; her assets beyond figures". Does it not seem like the limit of nonsense for a country that is not paying its running expenses to make such pretensions? After fifty-five years of Confederation and much talk of national status we are still sponging on the mother country for our external defense; we still allow the hard pressed tax-payer in the old land to shoulder the entire burden. We even now refuse to accept able-bodied working-men from that small and overcrowded country and yet blatently talk of limitless resources.

Jan 1, 1923

"The success or failure of coal mining operations in Western Canada may hinge on the ability to extract thick coal under a variety of geological and mining circumstances and conditions. The paper presents, in who-where, what- how pattern, the current status of undergrounud mining of thick coal seams based on a review of foreign technical literature. The underground production of coal from what are considered to be thick seams is over 300 million tons per year. Methods of mining have evolved, through years of trials and tribulations, capable of meeting the requirements of a modern mine: high bulk outputs from a limited number of mining faces by concentrating in the horizontal (mechanization) and in the vertical (increased working lift)."

Jan 1, 1972

By J. A. H. Church

The report is too voluminous to be considered in detail within the scope of a single paper, so I will confine my consideration of it to the broader aspects, leaving other members to deal with points of particular interest. The method of presentation leaves one with an uneasy sense of prolixity and confusion of thought; the foreword by the Chairman may well be accepted as a true index of the whole. His argument amounts to this: Recognizing at the outset the futility of divided counsels, it was deemed advisable to arrive at unanimity. To this end, some members subscribed to views to which they do not whole-heartedly assent, thus giving weight to conclusions with which they were at variance. Unanimity cannot be qualified-either it exists or is absent-and, moreover, in the text of the Com-mission I can find no word that unanimity is required. Surely it would have been preferable to have a unanimous report covering such aspects as were acceptable to all members, with minority reports by individual members on such other aspects as were controversial, leaving it to the Government to give such weight to the divergent views as the personality of their sponsors might warrant. In the final analysis the value of an opinion varies directly as the personality of its exponent.

Jan 1, 1926

"Option pricing is used in finance for valuing options to buy (or sell) shares at some future date because it provides a convenient framework for quantifying values subject to uncertainty. As one of the main sources of uncertainty in mining is the price (sales) of the metal, this approach can also be used for valuing mining projects.The first part of this paper reviews options and option pricing; the second part presents the approach developed by Brennan and Schwartz (1985) for using option pricing to value natural resources. Several applications of this methodology have been published; these are described. From a mining point of view, the assumptions made by Brennan and Schwartz are too simplistic. The weaknesses are discussed with a view to improving an apparently promising new way of assessing the value of projects. IntroductionThe collapse of the British merchant banking group, Barings, has highlighted the risks that can be incurred by speculators and arbitragers in the futures and options markets. But this negative attention on futures and options should not make us forget their positive aspects. They can provide producers and consumers of metals with more predictable sales prices. The introduction of the new traded average price options, TAPOS, by the London Metal Exchange in January 1997 is a response to this need. Equally important, the theory that the finance industry has developed for valuing options provides an interesting framework for valuing mineral projects as well. While this paper was being revised, the South African gold mining house, JCI, announced that it was using a methodology based on option pricing for valuing the mineral rights to deeplevel gold resources (see Box 1)."

Jan 1, 1997

By E. A. Sobering

Hydraulic filling or sand filling is a system used to fill underground excavations with a dense pulp. Milltailings are commonly used. The resultant fill, after being placed and de-watered, is known as hydraulic fill. These fills have been effectively used to (a) provide immediate support of the workings place during stoping; (b) .facilitate the recovery of pillars; (c) limit surface damage by subsidence; (d) permit the mining of parallel hanging-wall orebodies; (e) stabilize the ground in mines, thereby reducing the rock burst hazard; (f) control and prevent mine fires; and (g) solve tailings disposal .problems. The various uses of hydraulic filling have been developed during the last ninety years. In 1864 it was employed only to control surface subsidence. Since then, this system has been successfully applied to meet specific ground support problems. Methods of handling mine-fill derived from a source outside the stope include transportation ?Of the material by hand, mechanical, pneumatic, and hydraulic means, or a combination of these methods. The hydraulic method has many advantages not found in the others; a significant advantage is the low compressibility of the material when compared to other mine-fill material. The hydraulic filling operation includes the .preparation and transportation of the pulp. The underground practices in .placing the fill vary from mine to mine. The chief reason, formerly, for using hydraulic fill was the exceptional support it provided, but recently it has proven an important means of reducing mining costs. This is especially true where labour is a large part of an alternative method, or where timber consumption is greatly reduced. The indirect benefits of hydraulic filling are probably as important as the direct benefits, and few important disadvantages exist.

Jan 1, 1956

By Aaro E. Aho

Yukon, one of the most potentially accessible, relatively undeveloped, regions of Canada, has major mineral possibilities. The Klondike placer gold fields and the Mayo silver-lead ?district are the sole major producers but large base-metal re-serves have been discovered in re-cent years and important asbestos deposits are now being explored. Several major exploration companies are active in this region despite short seasons, permafrost overburden, remoteness, lack of transportation, and resultant high costs. Pro-posed new roads can be expected to accelerate development. At ?present the major future mineral possibilities are considered to be lead-zinc, copper, aslbestos, silver-lead, gold, and mineral fuels. These and other mineral possibilities are outlined for various geological subdivisions of Yukon. Major favourable metallogenic features of Yukon include complexity of rock types and structures, widening of the Cordillera with cross-trends, and variety and quantity of mineralization found even with limited prospecting. Comparisons with southern 'British Columbia and the U.S. Cordillera suggest that further exploration will result in discovery and development of more major ore deposits and reserves which will eventually revolutionize economy of mining in Yukon. Such mineral resources, with interior petroleum and natural gas possibilities, and ?huge coastal hydroelectric power potential, are the foundations of a much larger future mining industry in Yukon.

Jan 1, 1958

By Milton C. Graves, Marcos Zentilli

"Gold has been reported from most geological environments in Nova Scotia; however, virtually all production (circa 2,000, 000 troy ounces; circa 60 tonnes) has come from that part of the province to the south of the Glooscap Fault which is underlain by Lower Paleozoic rocks of the Meguma Group. Over fifty concordant sets of quartz-carbonate-arsenopyrite veins have seen production. The host rocks are greenschist-grade equivalents of Cambro-Ordovician flyschoid quartz wackes and shales folded and metamorphosed during the Devonian Acadian Orogeny. The veins were emplaced under conditions of greenschist-grade regional metamorphism and under the same conditions of tectonic stress that later resulted in the regional folds and penetrative, axial-plane slaty cleavage. Rapid filling of hydraulic fractures caused by excess metamorphic pore fluid pressure under Acadian tectonic stress conditions can account for the geometry and paragenesis of these veins.The ultimate source for gold deposits in most greenschist-grade domains remains in doubt, but these domains seem to have had ample gold within them available for mobilization. The work done, to date, on the gold geology of Nova Scotia suggests that regional greenschist metamorphism was an effective mobilizer and a potential concentrator of Au, As, W, Fe and S from these vast reservoirs.In rocks of pre-Acadian age north of the Glooscap Fault, gold occurs as an important accessory in volcanogenic massive sulphide ore, as a minor constituent in other types of basemetal concentrations and in one small concordant group of quartz veins.The post-Acadian metallogenetic domain, which overlies and overprints the two older domains, contains small amounts of gold in many mineralizing environments. Veins, with stibnite and gold, cross-cut crystalline rocks. Disseminated gold is present in basal conglomerates of post-tectonic molasse. Gold has been a by-product of Mississippi Valley-type Pb-Zn-Ba-Sr deposits in Lower Carboniferous sedimentary rocks and has been reported with Pb-Zn-Ba-F in veins which cross-cut Lower Carboniferous and older rocks. Small post-glacial placers have also seen minor production."

Jan 1, 1982

By J. S. Brock

Magnetic, electromagnetic and gravimetric surveys have played an important role in the mineral exploration leading to the discovery of three major massive sulphide deposits in the Anvil-Vangorda area of the Yukon Territory. During 1964 and 1965 a saturation prospecting program, relying heavily on the integrated use of airborne and ground geophysical survey techniques, led to the discovery of the Faro deposit, which was subsequently proven to be a 63-millionton lead-zinc orebody. Locating the Faro deposit, the largest found to date in this overburden-covered region, involved an exploration sequence requiring the selection of a favourable geologic environment, aeromagnetic and electromagnetic surveys, property acquisition of anomalous areas and detailed ground geophysical surveys, followed by rotary drill testing, detailed gravimetric surveys and diamond core drilling.

Jan 1, 1973