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By J. K. Atherton

If the metals sector is to contribute successfully to sustainable consumption we must adopt principles and practices which address the entire life cycle of the materials we produce. Progress must be founded on a sense of shared responsibility for the resources we utilize and the materials we create - it is this integrated approach which lies at the heart of materials stewardship. Materials stewardship means mining and metals companies producing materials in a responsible manner and then working with others, beyond their site, to ensure that the downstream material flows and applications are managed properly to create maximum societal value. In September 2006 ICMM published 'Maximizing Value: Guidance on implementing materials stewardship in the minerals and metals value chain'. This document takes a practical view presenting structured guidance as well as good practice case studies. In the publication, materials stewardship is described in terms of the range of activities that can be undertaken to ensure that all parties work collectively toward the responsible use of metal and mineral resources. This paper introduces the materials stewardship concept as set out in `Maximizing Value' and describes the business case for implementation as well as the ICMM framework for promoting materials stewardship.

Jan 1, 2007

By Arthur A. Cole

Although the metal silver has been known and prized from very ancient times, it is in the New World that the greatest silver camps have been found. This is shown in the following comparison: [] For the last few years, the World's annual production of silver has averaged about 240 million ounces troy. Of this total, the North American Continent contributes approximately three quarters, Mexico leading with 38 per cent, followed by the United States with 27 per cent, and Canada with nearly 9 per cent.[] Of the largest silver producers in Canada, the Sullivan takes first place. Although primarily famous as a lead and zinc mine, it produced, in 1926, more than 4.5 million ounces of silver. The Premier mine, in northern British Columbia, produced more than 3 million ounces. In Ontario, the largest producers in 1926 were the Nipissing mine, .with 1.9 million ounces, and the Keeley mine, with 1. 7 million ounces. The Mining Corporation produced 1.1 million ounces from mines in the Cobalt district proper, and an equal amount in South Lorrain; while from the Castle-Trethewey mine, in Gowganda, there was an output of slightly less than one million ounces.

Jan 1, 1927

By Roy O. Ifill, W. Charle Cooper, Alan H. Clark

"Queen’s UniversityIn representative, run-of-mine samples from the Panel and New Quirke mines of the Elliot Lake uranium district, Ontario, brannerite, ametamict uranous titanate, occurs in microscopic grain-aggregates which display wide variations, both in textural habit and in the relative proportions of brannerite, titania polymorphs and/or “uraniferous titania”. As is widely documented, much of the brannerite occurs as trellis-like arrays of laths and needles pseudomorphing rutile oranatase. In some cases, the laths and needles are cemented by coffinite. Brannerite, with an average composition of (U0.629Th0.039Ca0.20)(Ti2.199Fe0.13)O69contains =3 wt% Th and is distinctly Ti-rich relative to the ideal composition, UTi2O6. Much of the Si reporting consistently in electron microprobe analyses (between 1 wt%and 5 wt%) is tentatively attributed to contamination by the quartz-sericite matrix, and a minor proportion is attributed to the presence of coffinite intergrowths. “Uraniferous titania” (average par-tial composition by weight: 10.8% U, 0.3% Th,32.9% Ti) is considered to represent an intermediate stage in the conversion of titania to brannerite.The leaching behaviour of brannerite in its different modes of occurrence was studied qualitatively by the rotating-disc (polished section) method in H2SO4and HCl solutions at 25° to70°C. Redox potential was not measured. The progress of the dissolution of the individual brannerite crystallites and grain-aggregates was monitored by optical and scanning electron microscopes. Regardless of its morphology and texture (laths or needles, reticulate or blocky),brannerite is not readily leachable. Regardless of the process conditions, the rate-controlling step appears to be the initial leach-pit formation. These pits expand radially through the aggregate as leaching proceeds. This dissolution mode is independent of the relative amounts of brannerite and titania, i.e. the type of grain-aggregate. Secondary coffinite intergrowths are readily leachable and enhance the overall leaching kinetics of brannerite by accelerating leach-pit formation. These data provide, for the first time, information on the controls on the leaching of the uraniferous phases which dominate the lower-grade ores in the Elliot Lake district."

Jan 1, 1996

By Peter A. Hacquebard

"The early history of the Geological Survey of Canada is closely connected with coal geology investigations in the Atlantic Provinces. In 1843, Sir William Logan, the first director of the Geological Survey, measured the 4441m thick shore section at Joggins in Nova Scotia. Detailed mapping of the coalfields were subsequently carried out by H. Fletcher during the latter part of the nineteenth and first part of the present century. During the 1920-1940 period, the stratigraphy of the carboniferous WIZS' established by WA. Bell, who later also became a diretor of the Survey. Bell's work WIZS' followed by coal geology investigations of A.A. Hayes, W.S. Dyer, EA. Goranson, G. W.H. Norman, J.E. Muller, T.B. Haites and P.A. Hacquebord.The activities and accomplishments of the Survey geologists during the past 150 years are presented in this paper.General Outline of Survey Activities in Coal Geology During the Past 150 YearsIn 1842, when the Geological Survey of Canada (GSC) was established, the industrialization of the major countries of Western Europe and North America was actively persued. The energy required for this industrialization was obtained from the only fossil fuel then available, namely coal. The measure of a country's major mineral wealth at that time was the availability of mineable resources of coal. Eastern Canada, where mining had been carried out since 1720, was known to be well endowed with valuable coal deposits. In the major fields of Nova Scotia (Fig. I) several large-scale operations had been started during the middle and latter part of the nineteenth century.The significance of coal, therefore, was well understood, and exploration surveys specifically oriented toward coal were carried out by the Geological Survey from its earliest beginning. The first report of a detailed geological description of the coal measures of eastern Canada was prepared in 1843 by Sir William Logan (1845), the founder and first director of the Geological Survey of Canada. This early work was continued and complemented in 1896 by H. fletcher (1906), who during the latter part of the nineteenth century and first part of the present century systematically mapped the coal-bearing regions of Nova Scotia, which he considered all to be of approximately the same age."

Jan 1, 1992

By D. M. Muir

The mineralogy of residues formed during the pressure acid leaching of arid region nickel laterite ore varies according to the salinity of the process water, alkali cation additives and the overall acid loading. In fresh water, hematite is the main iron-bearing leach residue component, together with amorphous silica and hydronium or sodium alunite/jarosite [(H3O,Na)(Fe,Al)3(SO4)2(OH)6]. As the process water salinity increases, or as NH4+ or K salts are added, alunite/jarosite is the kinetically favoured iron-bearing phase accompanied by an increase in acid consumption. The alunite/jarosite appears as two XRD distinct phases with different Fe:Al molar ratios. In weakly saline water, iron-rich alunite/jarosite slowly transforms to hematite and an aluminium-rich alunite/jarosite together with the release of acid. The addition of potassium salts forms a more stable alunite/jarosite whilst the addition of ammonium salts leads to greater transformation of alunite/jarosite at 250°C. Weakly saline process water gives enhanced nickel recoveries, whilst strongly saline process water gives lower nickel recoveries but higher soluble iron because of chloro-complexation. SEM and microprobe analysis shows very little nickel is associated with the alunite/jarosite and hematite phases. Nickel losses to the residues are attributed to adsorption on amorphous silica and to a lesser extent on alunite/jarosite.

Jan 1, 2006

By D. N. Thurston

Luscar Stereo commenced construction of the mine at Coal Valley, Alberta, in August, 1976. It is designed to produce approximately 2.5 million clean short tons of steam coal annually - 2.0 million tons per year being committed to Ontario Hydro and 0.5 million tons per year being committed to Neptune Terminals for sale on the export market. The project involves constructing a heavy-media coal preparation plant, erecting a 42-cubic-yard dragline, constructing a shop/office complex, and developing three surface mining zones and associated facilities. As there were no existing facilities in the Coal Valley area, it was necessary to establish access roads, an airstrip, temporary utilities, fuel supplies, a construction camp, rail upgrading and communication services.

Jan 1, 1978

By Antonio Laguna

During the past few years, synthetic efforts have been addressed to the synthesis of polymeric materials with optical or semiconducting properties or even with capabilities to act as sensors for volatile organic compounds (1). The most recent studies have been concerned with the synthesis of heterometallic systems with short metal-metal interactions and the determination of their optical properties. These complexes are undoubtly interesting from a theoretical viewpoint and include an emerging class of luminescent materials, in which the observed luminescence results mainly from the interactions among the different metal centers, as well as the environments of these atoms. The understanding of the photophysics and photochemistry of these products could permit the design of complexes with appropriate metals and ligands chosen for individual applications. Following a synthetic strategy consisting on reactions between acid heterometal complexes and basic gold precursors we have succeded in synthesizing supramolecular assemblies formed via acid-base stacking, which display tunable luminescence or selective and reversible sensitivity to Vapour Organic Compounds (VOC?s) (2-5). In this sense, in accord with previous Mössbauer studies carried out in the gold precursor complex [AuR2]- (R = C6F5), the basic properties of this and related materials have been employed as building blocks of supramolecular assemblies in their reactions with complexes in wich the metallic centers act as lewis acids as, for instance, Tl(I) or Ag(I) (6). For instance, in the case of silver, by reacting equimolecular quantities of [NBu4][Au(C6F5)2] with AgClO4, in acetone, a solid of stoichiometry [Au2Ag2(C6F5)4(OCMe2)2]n is obtained. The polymeric nature of this material in solid state is confirmed through X-ray analyses (figure 1). It consists of polymeric chains formed by repetition of Au2Ag2 moieties linked through short gold-gold interactions. Nevertheless, in solution, the nature of this polymeric materials was still a matter of controversy and, in this case, the optical properties have been shown as useful tools in order to obtain information. Thus, while dilute acetone solutions of this complex give a emission coming from pentafluorphenyl localized ??* excited states, in accord with the presence of isolated tetranuclear Au2Ag2 units, when the measurements are done at different and higher concentrations, a band that does not obey the Lambert-Beer law appears. This deviation is consistent with molecular aggregation in solution of these units through gold-gold interactions, and a clear correlation between the emssion wavelength and the structure in the solid state and in solution is shown (figure 2). DFT calculations accord with the observed experimental behaviour and show the nature of the orbitals involved in each transition.

Oct 1, 2003

By A. Brown

The swift decline of coal during the period of unprecedented expansion in the Canadian economy is a phenomenon deserving careful examination, because the underlying forces contributing to this decline may have broader implications in our national economy. At the present level of technology, coal is more difficult to process, transport and utilize than liquid and gaseous fuels. Fundamentally, it is a matter of limitation in technique. Because coal is a vast store-house of energy in Canada, the reduction of these limitations is in the long-term national interest.

Jan 1, 1967

By G. M. Humphrey

It is a great honour and privilege to be here in this distinguished company of the outstanding men in the mining industry and the political life of Canada. I fully recognize that I am so honoured as a symbol of the combination of American and Canadian leaders in industry who are partners in the sponsor-ship of the Quebec-Labrador iron-ore mining development which we are undertaking, and as such I want to express our great appreciation of the co-operation and assistance we have met on every hand in Canada, and the genuine friendliness and never-failing courtesy which we are always accorded. We are quite aware that it springs primarily from the very high regard in which our partner and sponsor, Jules Timmins, and our other Canadian associates are held. Their high standing among you is well known and we quite naturally fall heir to the benefits of the great esteem in which you hold them. Jules Timmins and his long-time associate, John Knox, were the original inspiration for our participation in this venture. It was their enthusiasm and vision which caught our interest and led to our joining with them in the years of exploration and search which have brought us to the threshold of this great development where we stand today. So much has been written of the details of our exploration and plans for future development that it would bore you for me to review them further here, but there is a phase of this development, and an extremely important phase of it, which I think has passed almost unnoticed and which it may be well worth while for me to bring to your attention this evening.

Jan 1, 1951

By D. A. MacLeod

DURING the past fourteen months, dust surveys have been made at thirty-six mines in the Province. These surveys are made to determine the concentration of dust in the mine atmosphere, the flow of air through the mine, the methods adopted to prevent the generation of dust, and the measures taken for its elimination. When high concentrations of dust are encountered, suggestions are given for its prevention ?and elimination wherever possible. Dust sampling is absolutely necessary to determine the effectiveness of any measure taken in the prevention and elimination of dust in the mine workings. Consequently, more time has been spent on this phase of the work than on any other. The apparatus used is the Devers circular konimeter and Zeiss microscope. At various mines, the Zeiss konimeter is used, and the dust counts taken by the two instruments have given results that are closely comparable; so much so that either instrument can be used with confidence and the results obtained will compare in accuracy with those obtained by the methods used in Ontario and South Africa. Before the Workmen's Compensation Act Amendment Act was passed in November, 1936, most of the mine operators were already keenly interested in the prevention of silicosis. This interest has been intensified at all the mines, and measures have been adopted to decrease the amount of dust in the mine atmosphere. Several operators have spent a large amount of time and money in bettering these conditions, and have met with decided success. Practically all others are adopting the known methods of prevention, suppression, and elimination of dust, that apply to their ?particular mines. To prevent the production of dust in underground workings should be the first, as it is the most important, aim, especially during the time the men are underground. An atmosphere free of dust cannot be obtained, but measures can be adopted to lower the concentration that is found? in the average mine.

Jan 1, 1939

By Robert B. Parsons

"With several hoots of the whistle, Canada's fiscal engineers are once again cranking up the income tax locomotive, in an effort to inject new stimulus into a stubborn economy. And once again, additional gears, wheels, levers, and other mysterious part s are being added to the already complex machinery in order to accommodate the new push.This time, a significant new mechanism involves a major overhaul and expansion of the investment tax credit system.Although the shiny new devices have considerable appeal to a certain group of potential passengers, one wonders if all of the renewed chugging and huffing is on the right track.IntroductionAs indicated in Tax Notes in the July 1983 issue of CIM Bulletin , the April 19, 1983 federal bud get introduced a number of new measures which would permit investment tax credits and research and development deductions to "" flow through "" from a corporation to another taxpayer."

Jan 1, 1984

By R. R. Rogers

ABSTRACT The experiments described demonstrate that crude commercial lithium containing in the order of 0.5 per cent sodium can be refined, the resulting metal containing as low as 0.001 per cent sodium. During the process, the metal is vaporized and condensed at a gauge pressure of less than 0.04 micron. Considerable operating data and a detailed description of the experimental equipment are included. INTRODUCTION DUE TO THE unusual properties of lithium metal, its use is likely to increase considerably during the next few years (1, 2). This is of particular interest to Canadians because there are important deposits of lithium-containing minerals, especially spodumene, in Canada and it is hoped that lithium compounds and lithium metal will be produced from these deposits in the fairly near future. In order to assist in the development of this industry, the Mines Branch of the Department of Mines and Technical Surveys has initiated a programme of research in lithium metallurgy. In 1948, a paper (4) was published on methods of producing lithium metal and its alloys. Data on the corrosion resistance of some lithium alloys were included. In 1949, a paper (3) was published which showed that the addition of a small percentage of lithium to zinc anodes used for cathodic protection will improve their usefulness under certain circumstances.

Jan 1, 1951

By Ashu Garg, Anirban Bhattacharya

"Friction stir spot welding of aluminum alloy AA6061-T6 sheets was performed with circular (plunge depths 0.4 and 0.6 mm), square and triangular tool pin (plunge depth 0.4 mm) with constant 0.2 mm shoulder penetration to characterize various zones of weld nugget. It was observed that the depth of the stir zone formed below the tool pin is comparatively similar for different tool pins but wider for circular tool pin. The size of another stir zone formed at the interface of tool pin and a tool shoulder is observed to be larger for triangular and square tool pin due to the higher swept rate. Predicted strain from finite element analysis, calculated strain rate using Zener-Hollomon relationship and experimentally measured grain size distribution indicates severe amount of plastic deformation in-and-around the nugget/spot region. Finer grains in various stir zones were observed than thermo-mechanically and heat affected zones. Grain size (at distribution peaks) in stir zones varied around 2.54 µm to 3.69 µm for different tool pin profiles as compared to base metal grain size of 20 µm. Microhardness results indicate that the welded region is quite softened than base metal and maximum hardness is mostly observed around the thermo-mechanically affected zone.INTRODUCTION Friction stir spot welding (FSSW) is widely used for joining the sheets of materials like aluminum, copper, magnesium, etc. The process begins by plunging a rotating tool (generally having a pin and a shoulder) into the sheets to be welded. Continuous stirring of the tool and downward plunging force generates localized heat due to friction at the tool-sheet interface and plastic deformation of the sheet metal. The material gets softened and the plasticized material adjacent to the tool pin starts flowing due to the action of tool rotation and tool plunge thereby causing intermixing and bonding between the overlapped sheets. The tool stirring also promotes grain refinement in the weld nugget associated with high strain, strain rate and thermal cycle. The formation of new microstructure also affects the mechanical properties and efficiency of FSSW joints. Studies also showed that the tool pin design and tool shoulder feature exerts a noteworthy influence on the material flow and intermixing during the FSSW process (Reilly et al., 2015; Hirasawa et al., 2010). Sarkar et al. (2016) studied the material flow and intermixing during FSSW using tracer material method and reported that the size and width of flow zone increases with tool penetration depth. The influence of tool rotational speed on microstructure and stir zone temperature was investigated during FSSW of dissimilar AA6061-AA5754 alloys (Gerlich et al., 2007). They reported that the average grain size in stir zone of AA6061 weld increases with increase in tool rotational speed. In another work, Gerlich et al. (2008) studied the local melting and tool slippage during FSSW of Al alloys. Tool slippage was investigated by calculating the strain rate using Zener-Hollomon relation. Garg and Bhattacharya (2017a) studied the effect of dwell time, tool pin profiles and tool rotational speed on shear strength, microstructure, temperature and strain distribution during FSSW of AA6061. In another work, Garg and Bhattacharya (2017b) analyzed the effect of different tool pins and pinless tools on the shear strength and microstructure during similar and dissimilar FSSW of AA6061-T6 and pure Cu. Chang et al. (2004) proposed mathematical relationship between the average grain size and Zener-Hollomon parameter during friction stir processing of Mg alloy. Solhjoo (2010) presented a mathematical approach to determine the critical strain as a function of peak strain required for initiation of dynamic recrystallization in austenitic stainless steel. Fratini and Buffa (2005) also proposed the numerical model to determine the grain size during continuous dynamic recrystallization phenomenon."

Jan 1, 2018

By J. Stiksma, R. Kalanchey, M. J. Collins, G. Owusu, R. Raudsepp, K. R. Buban, L. A. Barta, I. M. Masters

This paper describes the results of testwork for the treatment of Ambatovy laterite ore by a pressure acid leach process, with recovery of the soluble nickel and cobalt values as mixed sulphide intermediate by precipitation with hydrogen sulphide, and subsequent refining of the mixed sulphide to nickel and cobalt metals. These process development studies were carried out primarily in 2004, as part of a bankable feasibility study for the Ambatovy Nickel Project. The Ambatovy orebody is located in Madagascar. The mini pilot plant testwork was carried out in the Dynatec metallurgical laboratory in Fort Saskatchewan, Alberta. The results of the testwork were very encouraging, including nickel and cobalt extractions in the range of 95.5% to 97.0%, and 94.0% to 97.0%, respectively, in the ore leach step with sulphuric acid. High recoveries of nickel and cobalt were achieved throughout the remaining process steps, yielding separate nickel and cobalt metal powders with better than acceptable purity.

Jan 1, 2005

By M. D. Lawton, P. Steen

"Drilling results from the established levels at AngloRouyn Mines Limited had indicated inadequate tonnages to meet the planning schedule. It was decided to develop the main zone of the orebody below the bottom working level of the mine. The orebody dips north at an average of 50 degrees and plunges to the west at about 10 degrees. Due to the need for rapid development of this area, a decision was made to use trackless equipment.This paper describes the method used and highlights the use of small 5-ton diesel trucks as carriers for the 2-cu.yd LHD machine. The method achieved advances of about 1,000 feet per month, at a dip of 12 degrees over a length of close to 2,000 feet, using as few as 20 men per day."

Jan 1, 1971

By A. P. Page, G. E. Alexander, L. L. Sirois, A. A. Winer

A knowledge of the electrical surface characteristics of minerals is all-important in the choice of treatments to up-grade and beneficiate them. At their solid-liquid contacts, there are transfers of ionic species, which for insoluble oxide minerals are the H+ and OH-ions. The adsorption density of these ions can be detected by carrying out potentiometric titrations, and this paper describes the automation of such an apparatus. The details are discussed fully and the validity of the method is demonstrated by flotation tests.

Jan 1, 1969

By Larry M. Southwick

There have recently been executives at major metals companies who have recommended that Greenfield Projects not be pursued. Greenfield includes not only new geographical locations, but also new technologies and new types of feed materials. In the middle part of the 20th Century, two such projects were successfully commercialized to recover nickel from Cuban lateritic ores. One project (at Nicaro) used the Caron ammonia-ammonium carbonate leach and the other (at Moa Bay) a high pressure acid leach. How both of these projects dealt with these Greenfield issues will be reviewed, based on the original reports that described the research and development of the plants. This study will include a review of the critical ore characterization and sorting issues, as well as the extractive metallurgical, product recovery and equipment selection and sizing problems and how they were solved at each stage of project development, from laboratory through one or more pilot scale plants to start up and operation. In one case, a major revision of the plant was made after several years of operation to correct operating, equipment selection and materials of construction problems that hindered economical operation. These descriptions will provide a guide through the complicated and critical issues that in recent times have caused many companies to give up on similar development. Even with the more advanced analytical and computational tools available to today’s mineralogists, engineers and metallurgists, the basic concepts with which these projects successfully addressed their sets of problems are still required. In addition, upper management, now perhaps further removed from hands-on experience than was common then, will see how complicated problems require intense and detailed effort to avoid failure in the field and capital blowouts. Build it and we will make it run, kicking the can down the road and borrowing operating and design concepts incorrectly on technological issues, or nine year olds on a sugar high making financial decisions are not philosophies by which to succeed with Greenfield Projects.

Jan 1, 2014

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

By J. E. Rowland

NIOCALITE is a new mineral species which has been identified in rock from the Oka district, Quebec. It occurs as prismatic crystals up to l 0 mm. in length and I mm. in width, in coarse, white, crystalline calcite with associated apatite, diopside, biotite, pyrochlore, and niobian perovskite. The crystals of niocalite are light yellow in col-our and have a vitreous lustre. The optical properties of niocalite (I) are as follows: Biaxial negative -2V = 56° a = 1.700, [ ] = 1.730 Birefringence y -a = 0.030 Optic orientation: X = b, Z/\c 12°, Y , /\a = 32° The specific gravity is 3.32 and the hardness is approximately 6 (Mohs scale). A detailed analysis performed on 2.4 gm. of hand-picked material reveals that niocalite is essentially a calcium niobium silicate. Table I gives the result of the analysis. Crystals of niocalite, apparently suitable for X-ray diffraction work, were selected, and single crystal photographs were obtained using both Weissenberg and Precession cameras. Initial difficulties were encountered in interpreting these films, and in correlating the crystal data with the optical data. The in-consistencies were explained by the fact that every grain examined was twinned to some extent.

Jan 1, 1957

By J. Shahabpour

"Many porphyry copper deposits of the Kerman copper province in central Iran are associated with a consistent structurally con-trolled main drainage pattern, which is shown in this paper to be a useful regional prospecting tool in the search for new deposits. The main drainage trends also generally allow the distiction of high-grade (>0.2% Cu) from low-grade (<0.2% Cu) deposits. Topographic maps1:50 000 or geologic maps 1:100 000 have been found suitable for identification of promising drainages.IntroductionTrends of the main drainage systems transecting the high-grade porphyry copper deposits of the Kerman Region in Iran coincide with Quaternary age regional faults and fractures. Observation of such drainage trends can expedite regional evaluation prior to field examination. Thirty deposits located in the Kerman Region (Fig. 1) have been studied to identify common features that can be used for exploration purposes, especially for the first stage of regional exploration. A variety of field criteria are available for subsequent rapid field checking prior to trenching and more costly methods such as drilling, etc.Characteristic geomorphic features have been considered as aids in mineral exploration by many authors (e.g., Faniran, 1971; Piotrovski and Lubkashov, 1976; Verstappen, 1983). Clark et al. (1967) indicated the relationship between geomorphology and the supergene enrichment of copper in Atacama Desert, Chile, and correlated three periods of supergene enrichment with three periods of pediment disection. Seeland (1978) used fluvial drainage patterns for uranium and hydrocarbon exploration in the Wind River basin, Wyoming. Postolenko and Konopleva (1973) used the reconstruction of ancient valley systems for exploration of gold placers"

Jan 1, 1996