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By B. Rivard, D. Francis

A layered Archean magma chamber is exposed at the base of the Yasinski segment of the La Grande greenstone belt. This intrusive complex lies beneath a sequence of mafic volcanics and is underlain by granitoid basement which is crosscut by a swarm of gabbroic dykes. The gabbros of both this complex and the dyke swarm of gabbroic dykes. The gabbros of both this complex and the dyke swarm define a pronounced Fe-enrichment trend. The volcanic patterns of the La Grande and Eas tmain greens tone belts, however, define a series of iron depletion trends which originate in the iron enrichment trend of the gabbroic intrusives. These patterns suggest that the gabbros produced in the intrusive complex may serve as parental liquids for some of the lava suites of the James Bay greens tone belts.

Jan 1, 1984

By Henry Wurtz

OBSERVING in the Engineering and Mining Journal, of January 16th, 1875, page 35, a report of a brief discussion upon the nature and origin of this unique and interesting coal, I take the liberty-on thus finding it a subject of interest to members of the Institute, and especially as my name came into this discussion-to communicate some results which may serve at least to overthrow certain erroneous ideas that have prevailed. While I would not claim to have made much approach to an understanding of this mineral-the whole of what I call Apozoic Mineralogy being as yet dark and almost unknown ground-yet I believe I have shown that few minerals of such importance and abundance, and so long before the world, have been so singularly misunderstood. On first examination of a sample of the substance to which the name of carbonite has been given, my surprise was not small, at failing to recognize in it one individual characteristic of true coke; neither the hardness, lustre, color, streak, porosity, sonorosity, structure, fracture, nor any of the so-called "pyrognostic" characters. Indeed, comparison with any coke, or variety or modification thereof, seemed altogether fantastic. Therefore the controversy regarding supposed trap dykes, whose existence at the locality is denied by some, seems useless, as we have no question of a natural coking, there having been no coking at all.

Jan 1, 1875

By I. Demers, A. Blier, M. Mbonimpa, M. Benzaazoua, B. Bussière

The Doyon Mine in Quebec, Canada, evaluates the possibility of desulfurizing its tailings to produce material to be used as cover for the acid-generating tailings disposal site. Laboratory tests showed that a single-layer cover made of desulfurized tailings placed over reactive tailings can prevent the generation of acid mine drainage. Modeling with the software Vadose/W was used to optimize the design parameters, namely, cover thickness, water table position and residual sulfide content of desulfurized tailings following laboratory work. It was found that the optimal configuration includes a 1-m (3.3-ft) desulfurized tailings cover containing 0.8% S, with the water table kept at the interface between the reactive tailings and the cover. To maintain the cover performance to reduce oxygen flux toward acid-generating tailings even in the event of a long dry period, a sand layer is suggested to protect the cover from excessive evaporation. It is possible to reach the environmental objective for oxygen flux chosen for the Doyon Mine (10 mol/ m2/year) with the protective sand layer, even in extremely dry conditions.

Jan 1, 2009

By Winter W, Steele DA, Trudu AG, Gray CM

The Luzon arc extends for about 900 km from Taiwan to the island of Mindoro (central Philippines); in this area late Tertiary to Recent volcanism is considered to be the result of eastward subduction along the Manila Trench. The arc is composed of five segments, all of which have individual characteristics with respect to tectonic setting and magma chemistry (Defant et al., 1989). From the north to the south these are (Fig. 1): (1) the eastern Coast Ranges of Taiwan and the islands Lan-Hsu and Lu-Tao (Taiwan Segment), (2) the islands off the north coast of Luzon (Babuyan Segment), (3) the Northern Luzon Segment, (4) the Bataan Segment, and (5) the Mindoro Segment. Defant et al. (1988) suggest that the Bataan and Mindoro segments of the arc, both of which are characterized by different isotopic compositions and levels of large ion lithophile element (LILE) enrichment in the lavas, are separated by a 'pull-apart' zone, the Macolod Corridor.We are currently studying the mineralogy and petrochemistry of Late-Miocene to Pliocene volcanism in the Northern Luzon Segment (NLS), which comprises the geographic area of the Cordillera Central. This area has so far received limited attention, inspite of its wealth of porphyry copper, skarn and epithermal gold deposits. In this contribution we report the first results of our study of igneous rocks from the Mankayan Mineral District (MMD) which is located in the centre of the arc segment under consideration.

Jan 1, 1990

A record $18.7 billion worth of metals, non- metals and fuels was produced in the U.S. during 1962, according to a year-end estimate from the USBM. The 1962 total value, based on preliminary statistics compiled by the Bureau, was nearly $600 million more than in 1961. Most minerals gained both in value and volume of production during 1962 according to information collected by the Bureau. All mineral fuels except anthracite showed increases. Among nonmetallic minerals- other than fuels-gains exceeded losses by two to one. Metal production held steady as gains and losses balanced.

Jan 2, 1963

By AIME AIME

ARRANGEMENTS for the Annual Meeting of the Institute were well advanced at the end of December as the following program will show. Heretofore this has been printed separately, but its inclusion in the Annual Review issue of MINING AND METALLURGY will, it is hoped, make it more easily available for reference until the final program is issued, which will be distributed at the meeting. Added details will appear in the February issue. Last year's meeting drew a record crowd of over 2300 which should be exceeded this year. Early reservations at the headquarters hotel, the Waldorf-Astoria, or any other convenient hotel are desirable, as are prompt reservations for the Annual Dinner. No one need worry about too much speechmaking this year, for the honors will be awarded and accepted in a few words instead of a few paragraphs, in seconds rather than minutes.

Jan 1, 1939

By AIME AIME

THE American Institute of Mining and Metallurgical Engineers will hold its annual meeting in New York City, Feb. 9-12. The technical sessions, excepting the Sunday afternoon and evening sessions of the Mineral Industry Education Division (see the M.I.E.D. program) will be held in the Engineering Societies Building. The "All-Institute" luncheon on Monday will be at the Commodore Hotel; the Annual Banquet and President's Reception, the Smoker, and the Informal Dance will be at the Waldorf Astoria Hotel. The dinners of the Petroleum Division and the Institute of Metals Division will be at the Roosevelt Hotel.

Jan 1, 1942

The Greymouth Coal field is situated on the West Coast of New Zealand's South Island and has been mined for coal for more than 120 years. The area covered in this paper is within the Rapahoe Sector of this field and contains >200 million tonnes of low ash, low sulphur, bituminous rank coal. Paper No 6, presented to the 19th Annual Conference of the New Zealand Branch of The Australasian Institute of Mining and Metallurgy in Christchurch in August 1985 by R G Bowman, explained 'A Geologist's View' of the 'Economic Potential of the Greymouth Coalfield', and describes previous geological assessments of the Rapahoe Sector.

Jan 1, 1989

By E. P. McCurdy, William J. Tait, Allen E. Craig

The Circuitron herein described applies current from the classifier motor circuit and energy from the sound of grinding media to move an oscillating disc. The disc through a photoelectric cell controls the speed of the ore feeder and consequently the amount of ore delivered to the mill.

Jan 10, 1950

By Jay A. Carpenter

THIS preliminary report from the Committee to Study Relations Between Students and the Institute is submitted to our member- ship for consideration and discussion before the general subject comes up for action at the Annual Meeting in February. At present, the A. I. M. E. has a dual relationship with mining students, each relationship in no may connected with the other. To the individual student the Institute offers for $2 a year a Student Associateship in the Institute which carries with it a subscription to MINING AND METAL- 'LURGY, a watch fob, and the privilege of becoming a Junior Member after graduation without payment of the -first year's dues, if one's application is accepted. To the student's college society it offers the privilege, upon application, of becoming 'an Affiliated 'Society, which brings with it no specific supervision or aid, and in turn requires no specific conditions as to membership, fees, or rules. This Affiliated Society is distinctly a school organization which Student Associateship in the Institute can he given special status or ignored, is the local .society sees fit.

Jan 1, 1934

By Eckley B. Coxe

AT the first meeting of the Institute, a paper was read by Mr. Rothwell, calling attention to the importance of at once considering the great waste of anthracite coal under the present system of mining and preparing that fuel for market, and a committee was appointed to examine and report upon the method now in use. About the time the committee were selected, a general resumption of work, after the long strike, took place in the coal regions, and the members of the committee have not in consequence had as much leisure to devote to the study of the question as its importance de¬mands. In the present preliminary report we shall merely sketch out the plan which we propose to pursue in our investigations, so that when our fellow-members are called upon to assist us in our work by fur¬nishing statistics, etc., they may understand more clearly for what object our inquiries will be made. As one of the most practicable methods of obtaining the informa¬tion requisite for an intelligent consideration of our subject, we pro¬pose to send, from time to time, to members and others interested in the mining of anthracite coal, printed sets of questions relating to points under consideration. We would here impress upon our fellow¬-members the importance of filling up these papers as far as they can from their own knowledge. We would, of course, wish each ques¬tion to be answered as fully as possible, but we do not expect every one to answer them all. One question well answered would be of more use to us than the whole paper filled up with answers, many of

Jan 1, 1873

By Dubois Eastman

BEHIND the contrasting liquid-fuel technologies of Germany and the United States lie the basic differences of scarcity and abundance. The chemists and engineers of each nation have developed processes that accommodate available raw materials. In the United States, processing is based on an abundant supply of petroleum, which is refined into a variety of fuels and lubricants. Germany has little indigenous petroleum but has a readily available supply of coal that can be converted into liquid fuels and lubricants. As a result, in Germany several basic processes have been developed for the conversion of coal into synthesis gas (carbon monoxide and hydrogen). In turn, this gas is processed into products. As a normal function of its researches into petroleum processing, the petroleum industry in the United States has made careful studies of various conversion and synthesis techniques. A number of oil companies are carrying out independent development programs with the aim of synthesizing hydro- carbon products that can be marketed at a price that will compete with the price of refined petroleum products. American oil companies hope to perfect synthesis processes that will directly benefit the consumer. A good example of progress in these terms is the synthesis plant at Brownsville, Texas, which is based on the conversion of natural gas to synthetic fuels and other valuable products. When this plant is operated at near capacity, it is expected that the products will be able to compete favorably for the consumer dollar. The complete gasification of coal is a technique well rooted in history. As a controlled process on a small scale, it goes back centuries. As a practical technique on a commercial scale, it dates back to 1839, when "producer gas" appeared in Germany for limited industrial use. By 1873, "water gas," or "city gas" as it is sometimes called, was being manufactured commercially in the United States for use in heaters and stoves. The water-gas process was the cornerstone for modern synthesis. To older methods that were concerned only with carbon and oxygen reactions, it added hydrogen by means of steam. Thus far the goal of conversion was to produce gas for heating, lighting, industrial use, and cooking. The long step forward to synthesis was made in 1927, when Germany started to make gasoline from coal by means of the revolutionary Bergius hydrogenation process. A year earIier, Franz Fischer and Hans Tropsch had announced their process, which finally reached the

Jan 1, 1953

By W. D. Hausel

Archean supracrustal rocks of the South Pass greenstone belt of western Wyoming have been the State's most prolific source of gold and iron ore. Actual gold production statistics are incomplete, but as much as 400 to 500 thousand ounces may have been mined with some silver and tungsten as a by-product. Iron ore was also mined from the greenstone belt for 22 years, and production totaled more than 90 million tons. Immediately south of the exposed greenstone belt in the Oregon Buttes area, Tertiary boulder conglomerate, which has been eroded from the granite-greenstone terrain, may contain a gold resource of 28.5 million ounces (Love and others, 1978). The amount of gold placered from stream alluvium derived from these Tertiary conglomerates is unknown.

Jan 1, 1986

By John. C. Reed

THIS paper presents briefly some of the principal results of 3 ½ months field work during the summer of 1938 in the Chichagof mining district, southeastern Alaska. The report is preliminary and presumably will be followed later by a more complete report to be published by the Geological Survey. The paper is concerned principally with the structural geology of a block of steeply dipping graywacke as revealed underground in the Hirst Chichagof and the Chichagoff mines, the two principal mines of the district. The two mines have produced about $16,000,000 worth of gold and silver. The attitude of the graywacke, which is locally cut by dikes and sills of aplite, is remarkably uniform and trends about N. 62° W. The average dip is about 67° SW. The graywacke is cut by large faults, the best known of which are the Hirst and the Chichagof, whose average trends are about N. 30° W. and average dips about 75° SW. The faults at some places split into the bedding of the graywacke and at others are deflected from their normal trends for considerable distances along the bedding. The relative movements along the faults was northwest and up at about 30° for the south-west or hanging-wall sides. The ore bodies are elongate quartz lenses in the faults. Most of the quartz is mineralized but locally large quartz masses are too low grade to be mined. The emplacement of the ore bodies appears to have been structurally controlled in large part by the intersections of the faults with the bedding surfaces. Places where the faults split or are deflected appear to have been particularly favorable places for ore deposition. There has been some post-quartz movements along the faults but it is thought that such movements have not been extensive enough to greatly modify the original positions and shapes of the ore bodies.

Jan 1, 1939

THIS paper presents briefly some of the principal results of 3 ½ months field work during the summer of 1938 in the Chichagof mining district, southeastern Alaska. The report is preliminary and presumably will be followed later by a more complete report to be published by the Geological Survey. The paper is concerned principally with the structural geology of a block of steeply dipping graywacke as revealed underground in the Hirst Chichagof and the Chichagoff mines, the two principal mines of the district. The two mines have produced about $16,000,000 worth of gold and silver. The attitude of the graywacke, which is locally cut by dikes and sills of aplite, is remarkably uniform and trends about N. 62º W. The average dip is about 67º SW. The graywacke is cut by large faults, the best known of which are the Hirst and the Chichagof, whose average trends are about N. 30ºW. and average dips about 75º SW. The faults at some places split into the bedding of the graywacke and at others are deflected from their normal trends for considerable distances along the bedding. The relative movements along the faults was northwest and up at about 30º for the south- west or hanging-wall sides. The ore bodies are elongate quartz lenses in the faults. Most of the quartz is mineralized but locally large quartz masses are too low grade to be mined. The emplacement of the ore bodies appears to have been structurally controlled in large part by the intersections of the faults with the bedding surfaces. Places where the faults split or are deflected appear to have been particularly favorable places for ore deposition. There has been some post-quartz movements along the faults but it is thought that such movements have not been extensive enough to greatly modify the original positions and shapes of the ore bodies.

Jan 1, 1939

By H. Shimoda, K. Tamaki, K. Iizasa, M. Watanabe, K. Okamura

Modern Kuroko-type deposits occur in submarine calderas of island-arc fronts and back-arc rifts in Japan. They occur primarily on or adjacent to caldera boundary faults. Hydrothermal sulfides in the Myojinsho submarine caldera are one of Kuroko-type deposits, but their occurrence is different from other deposits found within the area 200 km2 around the Quaternary volcanic front of Izu-Ogasawara arc.

Aug 24, 2006

By Qingsheng Liu

A new method of recycling aluminum dross for preparation Al-Si-Ti alloy was studied in this paper. This was carried out in two processes. first the aluminum doss was pretreated by leaching and calcining process, the fine purity and phase of the intermediate oxide powder up to electrolysis demands, then, could be obtained when aluminum dross after washing have been leached for 2h at 100? in 20% hydrochloric acid and calcined for 2h at 1200?, which was treated by cryoite-based molten salt electrolysis. Finally, the Al-Si-Ti alloy was successfully obtained through electrochemical co-deposition in the cathode shows a typical as-cast microstructure. This new recycling method can produce high quality alloy and may bring remarkable economic and social benefits.

Jan 1, 2010

Block caving is an underground mining method for the profitable extraction of massive, low-grade orebodies. Lately, it has become the mining method of choice, for many mining companies, because of depleted high-grade orebodies, and declining metal market prices. Block cave mining, however, still faces several challenges. Lack of access to the cave remains a major issue in understanding the rockmass response to mining for method optimisation. Improving our understanding of the rockmass response to caving will lead to safer and more productive operations. Combining large datasets from multiple sources with virtual reality scientific visualisation (VRSV) is a viable alternative to understanding complex cave behaviour without access to the cave. This is achieved using immersive environments with the ability to view complex multi-dimensional data (beyond 3D) graphically. VRSV offers a unique platform where it becomes possible to immerse the multi-disciplinary experts, and/or management team, in a virtual mine environment for quick decision making and fast resolution to conflicting conclusions. The underground mining system is complex due to multiple interrelating factors such as geology, excavation geometries, stress and time. Block caving is even more complex than most underground mining methods due to the network of tunnels required, and the use of induced stress, among others. As a consequence of the complexity in the block caving environment, it is vital that the mining system is analysed holistically, as a system, rather than optimizing individual factors one at a time. This paper presents a customised software module developed for use in the Advanced Visualisation Interactive Environment (AVIE) at The University of New South Wales (UNSW), Australia, to enable VRSV investigation into block cave mining systems (BCMS). This approach has the potential to provide a better understanding of the effect of time in in rock engineering, which has proven to be an important factor in hard rock mines (Ma & Daemen, 2006; Malan et al., 1997; Suorineni, 2010) but never validated. This work back analyses the early undercutting phase of a case study block caving operation with the view to understanding time/sequence effects. There is evidence that heterogeneous rockmass time-dependent behaviour governs the seismic response of the rockmass following undercut developments.

Jan 1, 2015

By L Munholand, G. Soucy, P. Quintal

This work presents early results from the first study to optimize the hydrodynamics of a Plasma Lift Reactor (PLR). The PLR is designed to break down organic contaminants in aqueous solutions. New experimental results are presented for air/water tests and for plasma degradation of organic contaminants in Bayer liquor. In addition, a multiphase Computational Fluid Dynamics (CFD) model has been developed which predicts the hydrodynamic behavior in the PLR. These results of this work suggest the PLR is effective at reducing contaminants in the Bayer liquor and that the CFD model adequately describes the hydrodynamic flow.

Jan 1, 2005

By F. B. Henderson, D. Bird, P. L. Hauff, E. C. Prosh

A National Aeronautics and Space Administration (NASA)-funded project (NASA Grant #NAG13-02026) is underway to determine the ability of hyperspectral remote sensing to map mineralogy that affects water quality within a watershed and to identify the relative contributions of natural and anthropogenic sources to that drainage. Natural sources, particularly areas of pyritic hydrothermal alteration, have been found by the Colorado Geological Survey to be a significant source, sometimes the only source, for acidity and/or metals in a number of areas of Colorado (Neubert, 2000). This situation undoubtedly occurs in many places in the Western United States and elsewhere where metallic mineralization occurs. Anthropogenic sources arise from mining and other human activities that increase the exposure of acid-generating materials to weathering processes, thereby increasing acidity and metal loading to drainages where that activity is occurring or has occurred. This project is attempting to determine if these sources can be differentiated through mineralogical analysis, in conjunction with surface water chemistry that controls the precipitated minerals, of the impacted drainages by remote sensing techniques.

Jan 1, 2003