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By H. A. Hamza

An experimental study of the settling characteristics of a washery effluent originating as tailings from a froth flotation circuit was undertaken by using a systematic approach to select the most appropriate flocculant(s) under predetermined conditions. Selection and evaluation procedures which greatly reduce the effort required to select flocculants are described. The results show that, although different flocculants display superiority at different ranges of dosage. Separan MG 700 (Dow) is the most suitable on absolute economic grounds. Flocculant evaluation is based on a Cost Performance Index (CPI) which expresses the cost of flocculant (¢/ton) required to produce a unit settling rate (in./hr). From experiments carried out with a number of flocculant aid and flocculant combinations, it was concluded that the use of flocculant aids can be economically justified only if the settling rates required are higher than those obtainable at the optimum flocculant dosage. Otherwise, the value of the flocculant aid appears to be limited largely to the reduction of supernatant turbidity.

Jan 1, 1979

By Stefan Boshkov

THE ADVENT of mining at great depth has brought to the fore the question of stresses around mine openings. The many-pronged attack on this problem is certified by the accelerated appearance, in the mining literature, of articles on various topics related to this subject (1). Whereas it may be agreed that we, of the mining profession, have fallen woefully behind in research and the development of an understanding of this important facet of the general problem of mining, it must also be accepted that the analysis of the stresses in a mine structure is usually more complex than is the case in the majority of structures encountered and dealt with in civil engineering. Whereas homogeneity and isotropy are readily acceptable for most metals, such properties are but crudely approximated in rocks. Whereas the external loads on a structure in civil engineering may be readily determined, those on a mining structure are subject to ?conjecture. Whereas the limits of the structure may readily be defined in civil engineering, the boundaries of the mining structure are, in most cases, indeterminate, and subject to intelligent guesswork, at best.

Jan 1, 1956

By Jochen Petersen

This paper gives an overview of the various strands of postgraduate and undergraduate training offered in the Department of Chemical Engineering at UCT. Since 2003 the Department is offering a formal postgraduate MSc programme in hydrometallurgical engineering aimed especially at graduate work-based engineers, with 5 weeks of intensive course work plus a research dissertation on a work-related project. This programme has now run 5 times over the years and produced some 20 degrees. The paper reflects on the experiences with running the course, especially the difficulties experienced with supervising industry-based external students. Furthermore, through the Department a graduate training program is offered for all junior metallurgists at a major South African minerals company. This 2-year program, which is currently on its 12th cohort, offers 1 or 2 week intensive blocks of course work alternating with longer stints where the candidates are based at various operations. Although primarily focussed on minerals processing, it has a significant element of hydrometallurgy in it and in recent years an advanced hydrometallurgy stream has been introduced. The paper reflects on the development of the program over the years, the benefits it has provided to the company as well as some of the challenges that remain. Finally the paper gives an overview of hydrometallurgy related undergraduate and research-only postgraduate MSc and PhD projects at the university. Some emphasis is placed on the recently launched South African Minerals and Metals Research Initiative (SAMMRI), a joint government-industry programme to support university-based research in the area of applied metallurgy.

Jan 1, 2014

By Victor R. Eyzaguirre

Cerro Verde is one of several large porphyry-type copper deposits in Southern Peru. The copper occurs as primary sulphides, with a significant oxide capping. The exploitation of the deposit has been correspondingly divided into two stages, the first consisting of copper production from oxides, and the second from sulphides. Minero Peru successfully started the Stage I plant in June of 1977 with the first production of electrowon copper cathodes. This paper is essentially devoted to a description of the Stage I process, which can be summarized as follows: Ore is trucked to the primary crusher, where it is crushed to 225 mm and conveyed to a coarse ore stockpile. Ore withdrawn from the stockpile is secondary crushed to 65 mm, conveyed to a truck loadout bin, loaded into trucks and driven to the leaching pads. Ore is placed on the pads in lifts and sprayed with sulphuric acid solution to dissolve the copper. Copper-bearing solution forms a pond behind a dam at the lower end of each pad and is pumped from there to the solvent extraction plant. Copper is extracted from the leach solution into an organic phase and is then stripped from the organic phase to form a purified concentrated copper solution suitable for feed to electrowinning. In electrowinning, the copper is finally recovered as cathodes suitable for sale as refined copper.

Jan 1, 1978

By William C. Martin

"Consolidated Sudbury Basin Mines Limited owns two mines, 4 miles apart, near the southwest end of Sudbury Basin. The Errington mine lies close to the north boundary of Creighton Township and about 18 miles by car from Sudbury. The Vermilion Lake mine is in Fairbank Township, on the south side of Vermilion Lake.The first discovery of base-metal mineralization within Sudbury basin was made by James Stobie in 1897 at Stobie Falls on the Vermilion River, half a mile west of the Errington mine. A few years later Alphonse Oilier made a discovery of massive pyrite with base-metal sulphides near the west end of the present Errington workings.No work of consequence was done on these discoveries until 1924, when Joseph Errington acquired options on a large acreage of ground which was later taken over by the Treadwell Yukon Company Limited. After considerable diamond drilling this company sank No. 1 shaft in 1926. In the next three years, a large amount of underground development was done, a pilot mill was constructed and operated for two years. All operations ceased in 1931 with the fall in metal prices. While in operation the pilot mill treated 186,172 tons of ore the average grade of which was 1·07 per cent copper; 1 10 per cent lead; 4·60 per cent zinc; 0·03 ounces gold; and 1 70 ounces silver.Up to the time of closing in 193 l there had been completed at the mine 26, 790 feet of lateral work and 75,500 feet of surface and underground diamond drilling. The company records, however, showed no figures on ore reserves, except broken ore in stopes amounting to about 60,000 tons. A study of the plans, prior to reopening the mine in 1952, showed 1,450 lineal feet of ore (at 1952 prices) opened up by drifting on the 300-foot and 500- foot levels. It is clear that no comprehensive picture of the structure was had at this time. The orebodies were considered to be very irregular pods scattered through masses of quartzite-carbonate in a sheared zone about 800 feet wide. In some way the ore was believed to be related to the tuff-slate contact zone. With this picture it was impossible to make a reasonable ore estimate or even gauge the tonnage potentialities with any feeling of reliability."

Jan 1, 1949

By K. Morin, C. -Y. Hon, G. Lachapelle

"Air-sampling results suggest drill operators working inside environmental drilling cabs at an open-pit gold mine in Nunavut, Canada, are at risk of exposure to asbestos and silica (quartz). The authors installed RESPA® CF Vortex HyperFLOW® units, which showed promising results under laboratory conditions. The goal was to evaluate the effectiveness of these units under actual working conditions. Personal and area air sampling was conducted in drilling cabs with and without the unit and a Wilcoxon rank-sum test was performed to compare the results. Particulate concentrations were significantly lower in drill cabs with a unit installed than in those without.RÉSUMÉ Selon les résultats d’une campagne d’échantillonnage de l’air, les foreurs travaillant dans des cabines de forage environnemental dans une mine d’or à ciel ouvert du Nunavut, au Canada, risquent d’être exposés à l’amiante et la silice (sous forme de quartz). Les auteurs ont installé des unités RESPA® CF Vortex HyperFLOW®, lesquelles of frent des résultats prometteurs en laboratoire. L’objectif est d’évaluer l’efficacité de ces unités dans des conditions de travail réelles. Des échantillons de l’air inhalé par le personnel et dans les aires de travail ont été évalués dans des cabines de foreuses équipées ou non de cette unité ; un test de Wilcoxon (également appelé test de la somme des rangs de Wilcoxon) a été mené afin de comparer les résultats. Les concentrations particulaires étaient considérablement plus faibles dans les cabines de foreuses équipées d’une unité que dans celles en étant dépourvues.INTRODUCTIONGenerally, mining operations are associated with a variety of occupational hazards. In an open-pit gold mine in Nunavut, Canada, drill operators are routinely exposed to asbestos (primarily amosite) and silica (quartz)—two naturally occurring substances in the ore that is to be drilled (Table 1). Inhalation is the primary route of exposure for these two hazards, which are associated with respiratory health effects such as asbestosis and silicosis, respectively. In addition, asbestos and silica are classified as human carcinogens by the International Agency for Research in Cancer (2001, 2011). Given the toxicity of these two agents, it is imperative that precautions be taken to minimize the risk of exposure of the mine’s workforce. To address this matter, the mine has an exposure-control plan, which includes the provision of personal protective equipment, personal hygiene facilities, training, and a medical surveillance program. Furthermore, the mine performs occupational exposure assessments or air sampling on a regular basis because the morphology of the ore changes rapidly with respect to asbestos and silica content."

Jan 1, 2017

By Richard W. Hutchinson, Christopher Osterman

Abstract -The Selebi-Phikwe deposits are hosted by amphibolite to granulite facies gneisses of the Limpopo belt. The sulfide orebodies are generally stratiform and conformable to the foliation of the wallrock gneiss. Sulfide remobilization has occurred during metamorphism and has produced discordant sulfide veins, called piercement structures, which project into the hanging wall and foot­ wall gneisses. These piercement structures are compositionally similar to the stratiform sulfides, consisting mainly of pyrrhotite, pentlandite and chalcopyrite. However, texturally the piercement sulfides are coarse grained and inclusion-free, whereas the stratiform sulfides are fine grained and packed with tectonically produced wallrock inclusions. The piercement structure sulfides and adjacent stratabound sulfides were sampled and analyzed for major base metals and PGE's for comparative purposes. Most of the piercement structures were enriched in Cu, Ag and Au, whereas they were generally depleted in Ni, Co, Fe and PGE's. Changing elemental associations were observed from the stratabound sulfides and along the length of the piercement structures. This and the degree of depletion or enrichment of various major and minor elements in the sulfide piercement structures may reflect the relative mobilities of metals under metamorphic conditions. The similarities between sulfide piercement structures and the footwall Cu-POE veins in some Sudbury deposits are reviewed.

Jan 1, 1994

By K. Sakai, M. Miyaue, T. Aoki, T. Tani, S. Tanaka, N. Kudo

In the planning stage of a tunnel, due to limited available technology in the geological survey and the financial restriction, tunnel supports are often designed from unsatisfactory information, and the tunnel construction is started. Therefore, "observational construction" is carried out in the construction stage, in which the design is rationally verified and modified by observations/measurements. Moreover, the ground conditions ahead of a tunnel face must be predicted for efficient and safe tunnel construction. The authors have examined effective prediction methods to the ground conditions ahead of a tunnel face under construction of a mountain tunnel (Aoki et al., 2010) in view of the established method (Schubert et al., 1995). Though the prediction method of Schubert et al. requires the displacement in the direction of tunnel axis, it is difficult to obtain its accurate data by the electro-optical distance meter. Then, we have proposed a method that uses tilt sensors installed at the tunnel crown near the face to obtain the slight tilting information. To measure inclination of the tunnel crown, this inclinometer was originally developed as a daily management measurement, such that the geological condition and its possible change behind the face could be detected early, and a steady advance and construction safety could be ensured. This paper describes the method of forward prediction mechanism and advantages of this proposed method. It then presents the typical results of a field demonstration test at a tunnel under construction. Lastly, the predictable range from the stratum boundary at which ground stiffness changes are discussed based on the results of three-dimensional numerical analysis.

Jan 1, 2015

By W. M. Goodwin

"IntroductionIN THE preceding paper we have learned about Canada's resources of metallurgical coal. There is an adequate amount in Nova Scotia, a very large reserve on the eastern flank of the Rocky mountains, and a strictly limited supply on the Pacific coast. Added to these is an unknown quantity of coking coal in the Peace River district, at present rather isolated but possibly capable of industrial development in the future.The chief use of metallurgical coal is to make iron and steel. For this, an adequate supply of iron ore is required. So we should now scan the Canadian supply of iron ore, the possibility of its increasing use at home, and the probable markets abroad.Trade in iron ore tends to be international, as is the case with many other raw materials. The present tendency with iron and steel, in contrast, is to keep its manufacture within national boundaries, and there is no evidence that this will change much in the years to come. We should keep these two points clearly in mind when considering the disposal of iron ore from Canadian mines. We should remember, also, that the modern blast furnace and steel plant has such a large output that a correspondingly large population, reasonably compact, is needed to consume its products.Large Ore Supply in East, Small in WestCanada has now four major iron ore fields, well situated to serve adequately the eastern half of the country. Wabana .and Labrador are well placed to serve overseas markets and plants on the eastern seaboard and eastern interior of the United States and Canada."

Jan 1, 1952

By J. W. Matousek

The heat content of the waste slag from a typical smelting operation methods for estimating the thermodynamic properties of smelting slags, to include: -- heats of formation -- heat capacities (specific heats) -- heat contents -- melting temperatures -- heats of fusion The techniques are illustrated with the analyses of a nickel reverberatory furnace slag from Copper Cliff, an iron-making blast furnace slag, and a "lateritic" slag from a ferronickel operation in Colombia.

Jan 1, 2007

By R. S. Douglas

Introduction The operations of The Granby Consolidated Mining, Smelting and Power Company, L1mited, have always been concerned with the mining of low-grade copper ores. In the fifty years of this Company's existence, nearly 60,000,000 tons of such material has been successfully mined and treated. During these years, many changes in mining practice took place. However, at Copper Mountain, due to the large tonnages of very low grade material, it was realized that something more than changing mining methods would have to take place if these low-grade orebodies were to be mined at a profit and the Company and. its employees enjoy many years of successful operation and employment. Production costs were mounting commensurately with rising taxes and the increasing cost of supplies, labour, freight, and smelting, while the value of the product on the market was not increasing in price to compensate for the higher costs of production. A survey of the mineable ore in 1944 indicated that, of the 12,000,000 tons in the reserves, only 3,500,000 tons was now profitable ore. This reduction in the commercial ore reserves was a serious matter, as it meant that the mine had only two years of life at the profitable shipp1ng rate of 4,800 tons per day. Further, the location in the mine of the orebodies making up the 3,500,000 tons was not suitable for such high production.

Jan 1, 1950

By G. Favini

A Bayesian decision model of minimun risk, based on the probability and costs of mine discoveries and non-economic projects, is presented for massive sulphide exploration in the Canadian Shield. The sample used for the model is composed of data relating to forty mines, sixty non-economic sulphide occurrences, and sixty occurrences of graphitic and pyritic material. These economic and barren samples consist of drill-tested occurrences which were, in varying degree, characterized by conductivity anomalies. Given the large size, the reliability and the homogeneity of the data base available for massive sulphide exploration, it is shown that certain statistical models can and should be utilized as a tool for decision-making by explorationists. Given this data base, information theory tells us that only those signals that are independent of one another will transmit information with minimum error. An ensemble of six significant multilevel signals, markedly independent of one another and consisting of numeric and geometric form descriptions derived from Bouguer anomaly, aeromagnetic and physiographic maps, were identified and evaluated by case studies. The use of these signals as input in a simple statistical procedure, or in a carefully planned and experienced visual appreciation scheme, can be of significant aid in decisions concerning the choice of favourable areas or sectors to explore in detail. The method of discriminant analysis is theoretically and practically suited for the statistical modelling involved. By way of a simulation on our statistical model, the efficiency of the model and of the underlying criteria is determined for historic cases and, by inference, for its validity in future exploration. An approximate optimized solution is derived from the model which suggests that over 90% of the known ore could be found by screening, according to a model such as that herein described, and drilling only 30% of the targets (mostly barren) normally identified and tested in current and past exploration.

Jan 1, 1979

By Peter A. Hacquebard

"The coals of the Sydney and Pictou coalfields are generally classed as high volatile ""A "" and medium volatile bituminous coals but there are significant differences within and even beyond this rank. These are related to the observation that the coalification in eastern Canada is essentially post-deformational, resulting in a general increase of rank with depth in individual seams.Exploration drilling in the Sydney coalfield has shown that the rank increases offshore to M. V. bituminous at mineable depths and in the Pictou field to L. V. bituminous coal. There is also a marked easterly shift in rank within one seam at the same depth at Sydney, with the result that M. V. coal will be reached sooner in the Donkin Reserve area (at 700 m depth) than in the Lingan-No , 26 Reserve area (at 900 m depth). These rank changes are important for the manufacturing of metallurgical coke as shown with coke stability predictions based on petrographic analyses. The L. V. coal of the Pictou field can be used for blending purposes and is the only known L. V. deposit of mineable thickness in eastern Canada.In addition, the vertical rank changes between seams have been studied in ten boreholes. They are not constant within the confines of the Sydney coalfield. Four separate areas can be recognized, each with different coalification gradients, which can be related to changes in the paleogeothermal gradients . Variations of 2.5 degrees to 6. 7 degrees CI IOO m are indicated and geological causes for these changes are suggested.IntroductionThe Sydney coalfield is the largest and most important field in eastern Can ad a, and although it has been in production some 200 years, the remaining ""demonstrated "" resources of 1.6 billion metric tons can extend its production capability for at least another 100 years. All coals mined are high volatile "" A"" bituminous and have been used for both thermal and metallurgical purposes. For the latter rank variations even of a minor scale are of critical importance for the manufacturing of metallurgical coke.The significance at the present time of the Pictou coalfield, which has only modest remaining "" demonstrated"" resources of 60 million metric ton s, lies in the discovery in 1975 of a 14-million-ton deposit of low volatile bituminous coal. It is the only known low-volatile coal in eastern Canada and is suitable for use as a blend for metallurgical coal. As such, it could supply the Sydney coke ovens for a period of 30 years at the current rate o f coke production and replace imported American low volatile coal.Consequently, coal rank studies of the Sydney and Pictou fields are important not only from a geological point of view, but also because of economic considerations."

Jan 1, 1984

By J. Cayouette, C. Bolduc, P. Blatter

"The LaRonde mill was commissioned in 1988 and began treating ore from the Penna shaft in 2000. The mill has been expanded to accommodate 7,500 t/day, but ramped down to 6,000 t/day since the deep extension began. The process recovers gold, silver, and base metals. In 2008, the Goldex plant began trucking gold-pyrite concentrate to a treatment plant feeding pulp to the LaRonde mill, increasing gold output by 40,000 oz. In 2009, the high-grade Lapa ore processing facilities were annexed to the LaRonde plant, increasing gold output by 120,000 oz. This paper outlines the metallurgical considerations related to the treatment of different ore types.RÉSUMÉ Le concentrateur de la mine LaRonde a été mis en service en 1988 et a commencé à traiter le minerai du puits Penna en 2000. La capacité du concentrateur a augmenté afin de permettre le traitement de 7 500 tonnes de minerai par jour, capacité qui est retombée à 6 000 tonnes par jour (tpj) depuis le début de l’extension en profondeur de la mine. Ce procédé permet de récupérer de l’or, de l’argent et des métaux communs. En 2008, l’usine de traitement Goldex a commencé à transporter par camion du concentré de pyrite et d’or vers une usine de traitement alimentant en pulpe le concentrateur de LaRonde, augmentant ainsi la production d’or de 40 000 onces. En 2009, les installations de traitement du minerai à haute teneur de Lapa ont été annexées à l’usine de traitement de LaRonde, augmentant la production d’or de 120 000 onces. Cet article passe en revue les considérations métallurgiques liées au traitement de différents types de minerai.INTRODUCTIONThe LaRonde metallurgical plant in the Abitibi region of Quebec, Canada, evolved into a mature milling site following expansions in 2000–2003, thanks to improved processes, manpower, and water treatment capabilities that better accommodate the complex constituents of the LaRonde ore. The ore requires a sequence of grinding, copper- lead and zinc flotation, and precious metals leaching, ending with a carbon-in-pulp (CIP) gold recovery. A portion (35%) of the tailings is sent back underground as paste backfill after being treated with the SO2-air cyanide destruction process. The tailings area has a dedicated cyanide destruction and metal precipitation area through which the used water passes before returning as recycled water. A biological water treatment plant was built in 2004 to address water toxicity in the final effluent. The water toxicity was the result of the high sulfide content of the LaRonde ore (from thiocyanate or stable cyanide species buildup) and the use of 90% recirculated water in the mill. The water treatment plant uses bacteria to transform thiocyanate into nitrates and precipitate phosphorus from the water before it is discharged into the environment."

Jan 1, 2017

By A. B. Rossetti

"THE MISSION TO Offshore Scotland was in my opinion a very worthwhile venture, as it indicated the scope of the offshore oil and gas business and how we might exploit it to the fullest here in Nova Scotia - if our offshore fields eventually become producing fields. The writer was able to attend a considerable number of lectures and as a result gained some valuable know-how on the engineering design, financing and operation of the North Sea oil industry. There are many new fields of technology that had to be developed to overcome the North Sea's hostile environment and a great deal of the same technology will have to be developed to win oil and gas from our continental shelf. The visit left me with several impressions, which in the main are:(1) The high order of investment required to develop offshore oil. The investment ranges from 10 to 20 times that required for a similar output on land. Each barrel of oil costs on the average of about $2,- 500 per barrel per day.(2) Because of the high investments required, before the first oil is produced the field must be brought into production at the earliest possible date and initial lead time from decision to production is less than four years. In the British Petroleum field, working at a depth of 450 feet will require an investment of $900,000,000 to develop a production of 400,000 bbl per day. (3) The size and complexity of equipment required is beyond anything ever imagined. Problems which must be overcome are such factors as water depth, wind velocities, wave height, wave period, long periods of darkness, low temperatures, distance from land, and fog."

Jan 1, 1973

By Chris M. Healey

"Abstract- The Jasper Gold mine in northern Saskatchewan produced a total mill feed of 140 127 tonnes at an average grade of 19.0 g/t Au. Both diamond drilling and chip samples from under­ ground workings returned extremely high values, up to 12 851 g/t (375 oz/I) Au over 0.10 meter from a chip sample. In the presence of such extremely high grades, the accurate estimation of reserves is a major problem.ln the first part of this study, production data from the mine were used to evaluate the results of a variety of reserve estimation techniques in this environment. In two out of three cases studied, indicator kriging with assays cut to 342.9 g/t (10 oz/I) gave extremely good results. In the third case, however , indicator kriging gave unacceptable results. Instead, lognormal kriging of uncut data gave the best results.Secondly, from the same database, a number of drill-hole spacings were simulated, and reserves estimated from the simulations. As may be expected, the results of this analysis show increasingly better results with tighter drill-hole spacing. However, even with a 5 m by 5 m spacing the variation from actual grade was quite large. This is not a systematic under- or over-estimation of grade, rather a random scatter of results .The results of this study show very clearly the problems of deriving good estimates of reserves when extremely high-grade samples are encountered. There is a high degree of randomness to this database, so reserve estimation in this situation will remain a high-risk operation."

Jan 1, 1993

By J. G. Kelly, C. P. Brown

"In June 1983 a new borehole hoisting system was commissioned at Sherritt Gordon's Fox Mine. Twelve hundred tons-per-day of ore from the 2600 and 2800 levels are being hoisted to the 2000 level through an 8-jt diameter bored winze. This new method replaces the diesel truck haulage system which had been in operation at the mine since 1975.A study was initiated in 1980to determine the most effective method of achieving the required production. The study examined several hoisting alternatives including: expanding the existing trucking system; converting to electrically -powered truck haulage; and deepening the skip compartments of the existing main shaft. The alternative selected as the hoisting method most suited to the requirements was borehole hoisting.Development of the new system commenced in April 1982. Underground excavations included 700 feet of 8-ft diameter borehole, a hoistroom and headframe, storage bins, and a grizzly and rockbreaker station. Equipment installations included: a 5-ft diameter double-drum Nordberg hoist; a counterweighted Kimberley-type skip; two rockbreakers; and the steel sets in the winze. These installations were completed in June 1983. Some problems were encountered after the initial commissioning but these were solved, and since August 1983, the system has proven that the designed capacity is achievable within expected costs."

Jan 1, 1985

By Waldemar W. Koczkodaj, William O. MacKasey

Abstract - A consistency-driven pairwise comparisons method for mineral potential assessment is presented, using a simplified case of volcanic-associated massive sulfide type deposits as an example. Geological, geochemical, and geophysical criteria are considered on two levels: local and regional. The local geological criteria are subdivided into stratigraphy, lithology, alteration and/or mineralization, and structure. The concept of geomerit index and a procedure for computing this index are introduced. The method of consistency-driven pairwise comparisons can be combined with other quantitative and qualitative assessment methods, enhancing them by incorporation of nonmeasurable geological criteria (e.g., stratigraphy or lithology) and by computation of weights. The consistency-driven approach allows experts to refine at-times subjective judgments concerning exploration and land-use planning, and contributes to the improvement of mineral-potential assessments.

Jan 1, 1997

By Waldemar W. Koczkodaj, William O. MacKasey

A consistency-driven pairwise comparisons method for mineral potential assessment is presented, using a simpli?ed case of volcanic-associated massive sul?de type deposits as an example. Geological, geochemical, and geophysical criteria are considered on two levels: local and regional. The local geological criteria are subdivided into stratigraphy, lithology, alteration and/or mineralization, and structure. The concept of geomerit index and a procedure for computing this index are introduced. The method of consistency-driven pairwise comparisons can be combined with other quantitative and qualitative assessment methods, enhancing them by incorporation of non-measurable geological criteria (e.g., stratigraphy or lithology) and by computation of weights. The consistency-driven approach allows experts to re?ne at-times subjective judgments concerning exploration and land-use planning, and contributes to the improvement of mineral-potential assessments.

Jan 1, 1997

By H. C. W. Bosman

"Over the past five years, contributions from geologists and mining engineers were instrumental in the successful development of MEPS. It is a system of FORTRAN programs specifically designed to be used by mining personnel to solve geological and mining problems. MEPS is a flexible keyword-driven system. Extensive error editing procedures significantly reduce the time required to proceed from problem recognition to solution. Possibly the most attractive feature of MEPS is that computer solutions may be guided or selectively modified to obtain desired solutions. Some highlights of MEPS are:1. Vocabulary that is familiar to mining people.2. Geological data storage and retrieval.3. Statistical analysis and variograms.4. Contour maps of assays and geological horizons.5. Trend surface analysis with residual evaluation.6. Ore reserve calculations.7. Open-pit mine design.8. Marginal profitability calculations on pit walls.9. Production scheduling.10. Vertical cross-section plots indicating pit outlines, ore grade contours and selected geological horizons."

Jan 1, 1973