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By Charles J. Cohen, Donald F. Reed

"INTRODUCTION AND ACKNOWLEDGMENTSThis report supplements a previous report on work done in this same area 4/ but covers only the period from November 1945 to November 1946. The project was established in 1943 to investigate magnetite deposits in the northwestern Adirondacks by geophysical surveying and diamond-drilling for the purpose of increasing iron production in the eastern United States.In its program of investigation of mineral deposits, the primary objective of the Bureau of Mines is the more effective utilization of our mineral resources, that they may make the greatest possible contribution to our national security and economy. The policy of the Bureau is to publish the facts developed by each project as soon as possible after its conclusion. Maps showing the detailed magnetic surveys of the deposits and anomalies discussed in this report are on open file at the offices of the Bureau of Mines, College Park, Md., and at the University of the State of New York in the office of the Director of the State Science Service, Educational Building, Albany, N. Y.The Mining Branch, Lowell B. Moon, chief, conducts preliminary exami¬nations, performs the actual investigations, and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiation tests.The chemical analyses included in this report were made at the Eastern Experiment Station of the Bureau of Mines at College Park, Md., under, the general supervision of J. B. Zadra, chief, College Park Division, Metallurgical Branch, and the immediate direction of Dr. Alton Gabriel, in charge of the laboratory service unit."

Nov 1, 1947

By Robert T. MacMillan

An essentially chemical technique has been developed on a small scale for the efficient utilization of certain domestic titaniferous iron ores. Three main steps are involved: (1) Sintering the ore at 1,050° C. with carbon and soda ash to reduce the iron to metal powder, retaining the titania in the slag, (2) separating the powdered iron from the slag, after wet grinding, by magnetic or gravity methods, and (3) sulfuric-acid decomposition of the titania fraction to produce pigment and certain byproducts. The technique was first applied to the tailings from the Bureau of Mines bauxite-concentrating plant at Bauxite, Ark. A good grade of powdered iron was produced from this material. Subsequently, the work was diverted to the study of the titaniferous magnetite from the MacIntyre Mine at Tahawus, N.Y., because of the potentially higher recoveries of iron, titanium and vanadium. Ninety percent of the iron in this ore has been recovered as an iron powder analyzing 90 percent metallic iron and containing 2 to 3 percent TiO2. The remaining titania was found in the slag and was recovered as pigment-grade TiO2 by application of a suitable technique. The vanadium was distributed between the TiO2 fraction and the alkaline liquor resulting from the wet-grinding and magnetic-separation operations, with only a minor proportion retained by the metallic iron.

Jan 1, 1950

By Joseph Sopko, Xavier Lacourse-Dontigny

For the REM (Réseau Express Métropolitain) project, a 2500 m tunnel was built using a tunnel boring machine (TBM) under the Montreal Pierre Elliott Trudeau Airport (ADM). Although the geology under the Montreal Airport (ADM) would have been suitable for an excavation with a hard rock machine, the rst section reuired an earth pressure balance (EPB) TBM due to the soft soil located under wetlands. After excavating 280 m, the TBM was blocked in a transition zone of unconsolidated, water-bearing soils directly above the underlying bedrock. A free air intervention was not possible due to these geological conditions. After several failed attempts to create a slurry cake for hyperbaric interventions, a ground freezing system was designed and implemented, incorporating angled pipes drilled from outside the wetlands to directly in front of the cutterhead. This paper discusses the engineering reuired to form a frozen, water-tight zone in front of the cutterhead using liuid nitrogen. It also describes the complex method of replacing the disc cutters while holding the ground freezing system active in a manner protecting the health and safety of the workers.

Jun 23, 2024

By James A. Robertson

"In the Blind River area Proterozoic clastic and sedimentary rocks and minor volcanic rocks (The Huronian Supergroup) uncomformably overlie and trangress northwards over dominantly granitic Archean terrane (2500 + Ma) and are intruded by Nipissing Diabase (2ll5 Ma). Later deformation and metamorphic events are recognized. The developing depositional basin was controlled by the incipient Great Lakes Tectonic Zone marginal to the Algoman Craton.The Matinenda Formation (basal Huronian) comprises northwards-derived fluvial arkose, quartzite, and pyritic, uraniferous oligomictic conglomerate which contained in 1981 some two-thirds of Canada's uranium resources. Production to December 1981 from Elliot Lake totalled 98.3 thousand tonnes U for an average recovered grade of 0.1% U with an additional 671 tonnes U recovered by leaching at Agnew Lake. The remaining resources are at lower grades. Some thorium and yttrium have been produced. Minor amounts of gold reflect the paucity in the source area. Gold is better-developed in the Huronian north of Sudbury reflecting the local source area.The conglomerate beds lie in southeasterly-striking zones controlled by basement topography down sedimentation from uraniferous Archean granite. Uraninite textures, the distribution of monazite, and local enrichment by reworking indicate a syngenetic, probably placer, origin of the mineralization. ""Brannerite"" has formed by solution of uranium from the margins of the uraninite grains and redeposition on the original titaniferous minerals. Penecontemporaneous volcanics may have been a source for sulphur in some of the pyrite and of trace amounts of Co, Ni and Au. Some pyrite may be detrital, some may be authigenic and some introduced.Drab coloured rocks, uranium and sulphide mineralization, the presence of hydrocarbon (thucholite) and a post-Archean regolith formed under reducing conditions have been cited as evidence of an early Precambrian reducing environment extended to the atmosphere. Sedimentary features indicating fast-flowing water and possibly a cold climate imply that the uraninite would be exposed to whatever oxygen was present in the atmosphere under conditions which would inhibit complete solution. In the upper Huronian, red beds and in the Lorrain Formation a monazite - iron oxide assemblage and copper mineralization indicate more oxidizing conditions. . Similar uranium deposits occur at Agnew Lake and in the basal Huronian north of Sudbury there are minor uranium and gold values.Provenance, lack of complete oxidation, transportation and depositional processes, redistribution during diagenesis and possibly low grade metamorphism, and the lack of post-depositional destructive processes are the dominant factors in the formation and preservation of the ores. The modified placer theory of genesis is well entrenched and an exploration model for such deposits throughout the world is well-documented.Research continues on mineralogy and textures of the ores, detailed sedimentology of the ores and their host rocks, with particular emphasis on: provenance area, the influence of early Precambrian mineralization patterns on the mineralization present in the Huronian both in space and in time, fluvial sedimentation and diagenesis. Expansion and reopening of the mines of the Elliot Lake camp should facilitate further studies."

Jan 1, 1986

By John C. Edwards

The U.S. Bureau of Mines has constructed a smoke chamber and developed sensitivity tests for smoke detectors. Response of ionization-and optical-type commercially available smoke detectors have been investigated. Six smoke detectors were measured with respect to visually obscuring smoke characterized by a corresponding optical density for smoldering and flaming coal combustion in the smoke chamber. It was determined that for one type of ionization smoke detector the alarm time was nearly equivalent to that of an odor monitor's alarm for smoldering coal combustion experiments and earlier for flaming coal combustion experiments. The experiments showed that an average CO concentration of 5 ppm corresponded to an optical density of 0.022 m-l for smoldering and flaming coal combustion. Two of the commercially available ionization-type smoke detectors were more responsive to flaming than smoldering coal combustion at an optical density of 0.022 m-l, whereas the optical smoke detectors showed the opposite trend. The responsive characteristics of the detectors evaluated with respect to known smoke conditions in the smoke chamber shows their potential for use as mine fire sensors or part of a mine atmospheric monitoring system to improve mine safety.

Jan 1, 2010

By Dr. Daniel W. H. Su

t is both an honor and privilege for me to nominate Dr. Daniel W. H. Su for the inaugural Syd S. Peng Ground Control in Mining Award. I can think of no better candidate than Daniel that is deserving of this award ? an award to recognize technical excellence in advancing ground control technologies [and] approaches. Daniel?s education and career spans over three decades. Having graduated from National Cheng Kung University in Taiwan in 1972 with a B.S. degree in Mining and Petroleum Engineering, he spent the next four years in the Taiwanese military and mining industry, before moving to the United States, where he enrolled in West Virginia University?s Mining Engineering Department. He received his M.S degree in Mining Engineering from WVU in 1978; then in 1982 became the first person to ever receive a Ph.D. in Mining from WVU. His thesis was titled, ?Development of Ultrasonic Techniques for the Measurement of In Situ Stresses?.

Jan 1, 2006

"TREVIICOS CorporationINTRODUCTIONThe Walter F. George lock and dam was constructed on the Chattahoochee River between 1955 and 1963 with the double function of improving navigation and generating power. Its 82 ft. by 450 ft. (25m x 137m) lock can accommodate large barge traffic and its four generating units with a plant capacity of 150 MW have an average energy output of 453,000 MWH. The dam consists of a 1,496 ft. (456m) long concrete structure housing the spillway, a non overflow portion, the power units and two earthen wing dams extending to the Georgia and Alabama sides, respectively 5,810 feet and 6,130 feet long (1770m and 1868m). As soon as the reservoir was impounded it became apparent that excessive seepage was occurring. From 1962 to 1985 a series of remedial works was performed using several techniques, but the problems continued under the dam, jeopardizing its generating potential and possibly undermining its stability.Finally, the decision was made to construct a deep cutoff primarily under the concrete portion of the dam to remedy the problem. PROCUREMENTOn July 5th, 2001 best and final offers were solicited by the Corps of Engineers (COE) for the construction of a deep cut-off to be built in front of the concrete portion of the dam from the bottom of the lake and tied into it. The cut-off had to cross an existing lock structure and an underwater retaining wall, as well as the remnants of a steel coffer cell left in place from the initial construction.The specifications required that the wall be built with a minimum thickness of 24” (600mm) and that it extended from the bottom of the lake to elevation -5 (1.52m) into the Providence formation, an impervious layer.While the land portions of the wall were on average 208 feet (63.4m) deep, the marine portion started from up to 90 feet (27m) of water and continued through different rock formations for another 100 feet (30m).Contractors were invited to propose their own method of constructing the cut-off and offers would be evaluated using several criteria, including technical, economical, organizational and experience.Three proposals were received and on August 14, 2001 an award was made to the Joint Venture (JV) of Treviicos and Rodio."

Jan 1, 2014

By R. C. Gifkins, K. U. Snowden

The value of the index n in power ktivs for the stress sensitivity of minimum creep rale at lead is derived front results drawn from lite literature and from previously unpublished nork on commercial (99.99 pel) and high-purity (99.999 pel) lead polycryslalline and hi crystal specimens. In tests al 0.5Tm (22 to 50'C) for slvesses below 250 psi, n fulls to mily for poly-cr,yslullirle specimens, single crystals, and bicrystals, and toy grain boundary sliding in bicrystals. Between 250 and 500 psi there is a tyansilion range and, for the polycrystalline specimens al least, u high-stress regime for 500 to 1500 psi where n is 5 or 6. These results are such that none of the suggested stress taws can he used to extrapolate to very loir stresses. Meclianisms for deformation in Ike grains and toy grain boundary sliding in the low-strcss regime are outlined. In particular, the mechanism for grain boundary sliding involves sliding controlled by diffusion from tensile to compressire Ledges. predictions based on this model give promising numerical agree-nicul with experiment. II is suggested that the mechanism for grain boundary sliding may he important in other circumstances, e.g., in creep of ceramic materials or superplaslicity, because it can operate with lille or no dislocation aclirity. WhEN the stress dependence of secondary creep rate is represented by a power law the values taken by the stress exponent n are found to vary between 1 and 7, see, c.g., Garofalo.' In Eq. 1 11 u is the applied stress and A a constant. The case for accepting values of v = 1 rests principally upon tests at high temperatures (>0.9Tm) and there have only been isolated tests at lower temperatures (rather than plots of creep rate against stress) for which the creep rates are such that some form of Nabarro-Herring creep with n = 1 is applicable. Hanson5 and Greenwood and cole6 plotted creep rate against stress for tests made in the vicinity of 0.5Tw, and found a "creep yield", so that below a certain low stress the creep rate was linearly related to stress: these observations appear to have been subsequently ignored. Various models have been proposed which agree with a large body of experimental results in which n equals -5 at high stresses (e.g., weertman7 and McLean8). Various alternatives to Eq. [1] have been proposed principally as a means of unifying creep data, but sometimes, it seems, in order to obviate the necessity for assuming a series of regimes of deformation associated with the various values of n; further refer- ence to these will be made in the section on stress laws. This paper calls attention to extensive results which show n = 1 for the creep of lead at room temperature (0.5 T,). RESULTS Fig. 1 is a composite diagram based on figures in the literature6,9,10 with additional results obtained by the present authors and their colleagues11,12 in the course of a number of investigations not directly concerned with stress sensitivity. In Fig. 1 In creep rate is plotted against In stress. The curves show results for two kinds of material. Lead I is of commercial purity (99.99 pct Pb) and lead IT a specially refined material, hydrogen-purified to remove oxygen; it contains 99.999 pct Pb. Curve A is for lead I in polycrystalline form (grain diameter 0.02 to 0.05 cm) at room temperature (22' to 26°C). Curve B1 is for lead I, polycrystalline, tested at 50C. Curve B2 is for lead 11, polycrystalline (grain diameter 0.02 cm), tested at room temperature (22 O- Curves C to F relate to tests made of bicrystals of lead 11: all of the same nominal orientation ("Y" in Ref. 12). Curves C and V are for creep within the component crystals of the bi crystals at 22°C (AB and CD in Fig. 2). Curve E is for creep measured in a gage straddling the boundary, approximately 0.15 mm either side (BC in Fig. 2). Curve F shows rates of grain boundary sliding (as distinct from strain rates in the other curves), obtained by averaging the offsets of six marker lines on the bi-crystal boundaries. The principal feature of the results is that the stress sensitivity falls into two distinct regimes, according to whether the stress is below approximately 250 or above 500 psi (there is a transitional range between 250 and 500 psi). The new result is that below -250 psi two of the curves (A and BI) give a value of n 1, and the other curves also drop below n - 2 to -1.5 but do not extend to low enough stresses to show clear evidence of n 1. At very high stresses the curves tend to give values of n - 6, as previously determined in other investigations. Curve R2 for the high-purity lead in polycrystalline form at room tenlperature almost merges with B, and thus gives new significance to the values for stresses of 150 and 200 psi; previously'3 these points had seemed to fall away from the curve of slope -3, but they now can be seen as almost completing a transition to n = 1. It should be noted that there was originally considerable apparent scatter in the results for the high-purity lead. However, this was found to be associated with annealing conditions or variations in residual content of oxygen and curve B2 was constructed using the highest rate (i .e., the rate for the purest lead) determined for each stress during the course of various investigations over the years: altogether, some forty tests were used in constructing curve R2.

Jan 1, 1968

By D. K. Deardorff, Haruo Kato

D. K. Deardorff and Haruo Kato (U. S. Bureau of Mines)—We wish to refute the 1875" 20°C value that Giessen, et al., report as the transformation temperature of hafnium. Although these authors state that their work along this line will be reported later, we can't leave their value undiscussed, for we believe it to be 125°C too high. Our value of 1750° 20°C, which the authors mention, has been substantiated in our laboratories by the use of three other methods. The first method of substantiation was by heating and cooling curves using a hafnium/tungsten thermocouple, the couple having first been calibrated against a t/Pt-10 pct Rh couple. The second method was by quenching and metallography of dilute Hf-Ta alloys. The third cussion, it may be pointed out that the observations of Rogers referred to large unidirectional strains where the internal cracks or voids appeared only after a strain of 32 pct or more. On the contrary the internal fissures observed, as a result of fatigue cycling, occurred for a total extension of some 5 pct and furthermore followed the directions of the slip zones. Finally, it is not our contention, as implied in Dr. Alden's last paragraph, that the tensile stress is an important factor in crack propagation. Indeed, in connection with the reference to the companion report, special note is made of the fact that "Deformation was apparently concentrated in grains which have a slip plane nearly perpendicular to the specimen axis and thus near the plane of maximum applied shear." This dependence of the growth of fissures on the orientation of the slip planes with respect to the direction of maximum applied shear is clearly shown in work on the torsional cycling of single crystals which has been submitted for publication. method was by heating and cooling curves with W/W-26 pct Re thermocouple. Counting the original resistometric method, four different methods have yielded 1750" 20°C as the transformation temperature of hafnium. All our work on determination of the hafnium transformation temperature has shown that the specimen under test must be quickly heated to and through the transformation temperature if the lowest possible transformation value is to be determined; otherwise a higher value not representative of pure hafnium will result. Speed was emphasized in all methods. In our resistometric work the corresponding voltage, amperage, and temperature readings were taken quickly and the transformation temperature was usually reached within 5 min total heating time. In the thermal analysis work involving Hf/W or W/W-26 pct Re thermocouples the transformation temperature was attained within three minutes total heating time, this time being less because the two variables were

Jan 1, 1963

By T. Krumins, F. C. Ruff, M. Eichhorn, L. Zunti

Hatch Ltd. has recently completed a project to increase refractory gold ore processing capacity at Newmont Mining Corporation’s Twin Creeks facility. The objective of the project was to increase throughput by approximately 10% by adding a third autoclave feed pump to each of the two autoclave circuits. To minimize project capital cost, autoclave feed pumps from Newmont’s decommissioned Lone Tree facility were evaluated and found to be suitable for this new service. The existing pressure oxidation circuit was reviewed in a debottlenecking study to determine other upgrades required to facilitate the increased throughput. Interruption to operations was minimized with a detailed construction plan, supplemented with detailed 3D layout model sequencing studies. The focus of this paper is project development, multi-discipline design considerations, and implementation results.

Jan 1, 2014

By H. C. Roland Kammel

Stannous sulfate electrolytes are widely used nowadays in electrolytic tin production. Characteristic features of this electrolysis process are that dense cathode deposits can only be obtained by additions of organic additives and that so called ?black mud is formed on the anode surface which leads to an increase in cell-voltage. In order to prevent excessive cell-voltages or oxygen evolution the black mud has to be removed periodically. Studies in laboratory scale have been performed about the effect of different organic additives on electrolytic tin deposition and the formation of surface layers on pure and industrial tin anodes. Results reveal that organic addition agents are effective in reducing cathode roughening as well as extending the covering time of the anode ?by black muds.

Jan 1, 1985

By C. H. Ash

"The Red Chris Cu-Au deposit (522.7 Mt at 0.35% Cu and 0.27 g/t Au), northwestern British Columbia, is one of several pre-accretionary porphyry systems in the Cordillera of westernCanada. It is hosted by an Early Jurassic hornblende monzonite to quartz monzodiorite porphyry which forms part of a suite of dikes and stocks that intrude Late Triassic volcanic strata. Major and trace element chemical data suggest that these Early Jurassic intrusions have compositions which fall on the boundary between alkalic and calc-alkalic compositions. Alteration and mineralization in the Red Chris deposit are more typical of calc-alkaline porphyry systems with abundant potassic, sericitic and argillic assemblages and quartz-rich stockworks. It lacks Na- and Ca-bearing silicate assemblages which characterize the alkalic porphyry deposits of British Columbia. One of the more unusual features of the deposit is the abundance of carbonate alteration and veins which occur throughout the hydrothermal history of the deposit. This type of alteration and veining is more typical of alkalic porphyry deposits.The composition of the carbonates vary both temporally and spatially with different alteration zones. Potassic zones, which are characterized by orthoclase±albite±quartz±chalcopyrite±bor-nite±magnetite±hematite and Au/Cu ratios of 1:1 (g/t Au:% Cu), contain minor siderite veins and alteration. Quartz-sericite-carbonate (QSC) zones overprint earlier potassic alteration and comprisequartz+ankerite+sericite+pyrite+chalcopyrite with Au/Cu ratios of 0.5:1 (g/t Au:% Cu). Ankerite isthe main carbonate in this stage but has a variable composition with a more Fe-rich variety associated with mineralized veins. Localized chlorite-carbonate alteration zones, characterized by chlorite+carbonate+quartz±kaolinite±pyrite±gypsum and high Au/Cu ratios [2 to 3.5:1; (g/t Au:% Cu)],contain predominantly calcite. Late stage carbonate-gypsum veins have an ankerite to dolomite com-position which is very similar to the regional carbonate alteration and veins."

Jan 1, 1997

By John R. Freeman

The die pressing of brass may be described as a method of producing irregularly shaped parts of brass and other copper alloys by hot deformation in a die under pressure. Die pressing of brass was first developed as an improvement on sand castings in order to obtain irregularly shaped articles of brass with superior surfaces, a closer tolerance in dimensions, a denser structure, freedom from porosity and elimination of the relatively large amount of scrap invariably attached to sand castings. The freedom from sandy surfaces with consequent greater tool life in machining operations was also recognized as well as elimination of losses due to the uncovering of blowholes in machining operations. Die pressing also gave alloys of superior strength. Die pressings today are made from extruded rod or shapes, according to design of the part to be made. The greater number of pressings are made from round rod, because of its relatively lower cost and ease of handling. The rod is first sheared or sawed into desired lengths, the diameter of rod used and length of "slug" or "rivet" depending upon ultimate weight and shape of the die-pressed part to be made and design of die. The dimensions of the slug are figured so as to give the minimum amount of scrap to be sheared from the pressing as it comes from the die. Extruded shapes having I, T or X sections are often used when the finished part is to have a similar shape or heavy sections are joined by relatively light sections of considerable length. A rod bent in the shape of a U is also used on occasion, for similar reasons. Proper shearing of the slugs is of considerable importance. The sheared ends of the slugs should be as flat and straight as possible. Improperly sheared ends having an angle to the axis of the bar or a rough, uneven surface are liable to give folds or laps in the finished pressing and proportionately high rejections. The property of shearing varies considerably with different alloys and should be considered in the selection of a material for a given part. Where satisfactory shearing is not possible, the slugs may be cut from the bar by power saws. Extruded

Jan 1, 1931

By Lon D. Santis

This paper summarizes explosives transportation incident and accident data collected by the U.S. Department of Transportation (DOT) from 1993 to 1998. The paper briefly describes the legislation and regulations that cover hazardous materials transportation. The multimodal incident data collected by the Research and Special Programs Administration (RSPA) contained 86 incidents involving Class 1 materials during transit. Thirty-two occurred on public highways. The Federal Highway Administration (FHWA) data showed there were 8 1 motor-vehicle accidents involving explosives. The FHWA Crash datafile extract contained 649 records categorized as involving Class 1 materials although closer analysis revealed that nearly 90% of these did not involve explosives. In both databases, there were no fatalities caused by the explosive materials although 7 fatalities were the result of injuries suffered during the motorvehicle accident. There were also no serious explosions during any of these incidents or accidents. The paper concludes with an analysis of the risk involved with transportation of commercial Class 1 materials on the highway.

Jan 1, 2000

By Samantha Smith

Nautilus Minerals (Nautilus) is following the lead of the petroleum industry as it strives to tap vast offshore resources. Planning is well underway for the Solwara 1 Project in the Bismarck Sea, Papua New Guinea (PNG) to recover high-grade seafloor massive sulphide deposits in 1600 m water depth. The deposit contains an average copper grade >10 times higher than a typical land-based porphyry copper mine. The high grades combined with a relatively small amount of overburden ensure the Solwara 1 Project will have a significantly smaller physical footprint than its land-based counterparts. Offshore minerals production also has the advantage of minimal social disturbance. Nautilus is dedicated to setting a high environmental and social responsibility standard. Nautilus recognises the importance of transparent and inclusive stakeholder engagement and has taken a proactive approach to involve as many key stakeholders as possible. One of the first steps in the permitting process in PNG is the preparation of the Environmental Inception Report, which describes the project, its envisaged impacts and the proposed studies for the Environmental Impact Assessment (EIA). Local (PNG-based) and international environmental scientists, anthropologists, NGOs and other experts were involved in the definition of studies conducted for the Solwara 1 EIA and a team of world-leading experts was involved with carrying out the studies, culminating in the preparation of the Environmental Impact Statement (EIS). To ensure transparency, collaborating researchers are free to publish their findings. Following its submission, the EIS was made available for public review and public hearings were held at several locations. The EIS has also undergone a rigorous independent review by PNG government-engaged consultants. Outside the permitting process, Nautilus works alongside government officials to carry out ongoing community consultations. Information dissemination and feedback acquisition has also occurred through the Nautilus website and attendance at a number of international conferences, workshops, and meetings. This paper will outline the leading edge approach Nautilus has taken in completing the environmental impact statement for the world?s first deep seafloor copper-gold mine. In addition, this paper will review the permitting process and the government and stakeholder engagement undertaken as part of Nautilus? desire to ?do it right? in this exciting new industry.

Jan 1, 2010

By Alfred E. Hunt

By the death of Joseph Dame Weeks, past-President of this Institute, which occurred December 26, 1896, the world has lost an earnest and unwearied philanthropist; the Christian church, a zealous, active and consistent representative; the United States and the State of Penusylvania, a patriotic, pub-

Jan 1, 1898

1. Book reviews Geostatistics for natural resources characterization, edited by G. Verly, M. David, A.G. Journel, and A. Marechal. Hingham (MA 02043, U.S.A.), D. Reidel Publishing Co., 1984. Pt I: 606 pp. Pt 11: 518 pp. U.S.$135,50 per set. Reviewer: D.G. Krige Magnesium, the international perspective, by Peter King. London, Financial Times Business Information Ltd, 1984. £120. 147 pp. Reviewer: D.G. Maxwell 2. Mintek reports Report M156 A kinetic study of the reactions of certain gaseous sulphur compounds with iron. Report MI57 Reaction mechanisms in the reduction of Winterveld chrome spinel with graphite and carbon. Report MI72 Computer programmes for the control and datamanipulation of a sequential X-rayfluorescence spectrometer. Report MI77 A proposed test for the determination of the grindabi/ity of fine materials. Report MI86 A survey of the erosion, corrosion, and abrasion of material-handling systems in the mining and mineralprocessing industry. 3. New journal Advanced materials & processes, issued monthly by American Society for Metals (Metals Park, Ohio 44073, U.S.A.). CIM conference The combined 24th Annual Conference of Metallurgists and the 15th Annual Hydrometallurgical Meeting will be held in Vancouver from 18th to 22nd August, 1985. Light metals The 8th International Light Metals Congress will take place from the 22nd to 26th June, 1987. These meetings, which take place traditionally every few years, are organized by the Austrian Metals Industry Association, the Austrian aluminium industry, and the University for Mining and Metallurgy in Leoben, in collaboration with the Aluminium-Zentrale Diisseldorf. President of AS&TS* Mr Arthur Woodington Reynolds (Sam) took office as President of The Associated Scientific and Technical Societies of South Africa on 28th November, 1984. Sam Reynolds was born in Boksburg on 27th December, 1930, and received his education at Christian Brothers College in Boksburg and at St John's College in Johannesburg. World mining Sweden, Finland, and Norway expect representatives of all mining countries in May-June 1987 to the 13th World Mining Congress in Stockholm. The Swedish Mining Association, the Finnish Association of Mining and Metallurgical Engineers, and The Association of Norwegian Mines will organize the Congress, together with the International Organizing Committee of the World Mining Congress. Sheet metal The German Group of the International Deep Drawing Research Group (IDDRG) will be organizing the 14th Biennial Congress of the IDDRG on 21st to 26th April, 1986, in Cologne and Munich. Safety in mines The 21st International Conference of Safety in Mines Research Institutes is to be held in Sydney from 20th to 25th October, 1985. ILAF A conferences The Instituto Latinoamericano del Fierro y el Acero (ILAFA) has scheduled the following congresses for 1985. Mechanical testing of materials The Deutsche Gesellschaft fiir Metallkunde, together with the Deutschen Verband fiir Materialpriifung and the Fachhochschule Osnabriick, is holding a course on the methods used for the mechanical testing of materials at Osnabriick from 9th to 11th September, 1985. Mine ventilation The Second U.S. Mine Ventilation Symposium will be presented from 23rd to 25th September, 1985, in Reno, Nevada, by the University of Nevada-Reno's Mackay School of Mines and Division of Continuing Education.

Jan 1, 1985

By Q Qu

Reliable prediction of longwall gas emission sources and rate plays a critical role in mine ventilation and methane drainage capacity planning. Over the years, Australian longwall mines have been using the historic Winter method and the Flugge method in modelling specific gas emissions (SGE). The predicted results often experience high discrepancies from the operational reality. To improve gas emission prediction, post-mining gas contents were measured in several mines in Qld and NSW by safely drilling core holes into the longwall goaf. The results revealed many new insights into gas emission characteristics from different coal seams and the drawbacks of the European methods in their use in high-production gassy Australian longwall mines. Based on measurement data, a new, time-dependent gas emission prediction model has been developed. Considering several factors such as caving, desorption and production rate, the new model can predict more accurate and meaningful gas emissions to meet today’s needs in mine gas emission management. A case study is provided to demonstrate the application of the new SGE model.

Oct 12, 2022

By George A. Morgan

The production and processing of crude petroleum and natural gas are the dominant economic sectors of the Middle East. The IS countries that constitute the region accounted for 26% of world crude petroleum output, 17% of world natural gas plant liquid production, and almost S% of world dry natural gas production. About 66% of total world crude petroleum reserves and 31 % of total world natural gas reserves are in the Middle East. Transportation and port facilities in the region are geared to expediting efficient and rapid shipment of these materials. U.S.-dollar-denominated export sales of these fuels, estimated at $120 billion in 1989, provide funding for further diversification of the mineral industry. This is usually through development of downstream facilities for producing energy intensive metals such as aluminum and byproducts of the fuels such as petro-chemicals and fertilizers. Earnings from the industry are also channeled by sever-al Governments in the region to mineral industry projects in Africa and elsewhere. A fairly wide range of nonfuel minerals is produced in the region. However, the variety of minerals produced, output levels, and the size of the overall nonfuel mineral economy is dominated by Iran and Turkey. Turkey, with a diverse mineral production and strategically situated between Europe and the Middle East, ranked among the top three world producers of boron, chromite, pumice, and strontium. It was also a significant world producer of magnesium com-pounds, mercury, and sodium sulfate. Iran had generally lower output owing to 9 years of neglect to the mining sector between 1979 and 1988. It was a significant producer of gypsum and fifth in world production of strontium. Despite a very small domestic mineral industry, Israel was second in world production of bro-mine and a significant producer of phosphate rock and potash. Jordan ranked fifth in world production of phosphate rock. Iraq ranked about eighth in world production of sulfur, a commodity of major importance in the metallurgical, petrochemical, and fertilizer industries.

Jan 1, 1992

By Walter J. Frank

The purpose of the work covered by this contract is to develop a means of designing splice connectors which will significantly improve mine trailing cable splice performance. A brief discussion on splice problems is presented as an introductory means and substantiates the need for the development and test programs outlined in this report. Because of the empirical nature of this effort, time has been devoted to explaining the derivations of the test procedures used. Special attention is given to the splice flexing machine which served as the backbone of the test program. In order to familiarize persons with connector terminology, a section is devoted to a glossary of pertinent terms. Various types of cable joints are also defined. The major effort is a connector design parameter study. Utilizing the optimum parameters developed along with the suggested design procedure outlined in Appendix I should result in significantly improved splice performance and thus meet the objectives of this contract. A field test program was instituted for the purpose of insuring adaptability of connector design and associated installation tooling along with a field performance study. During the course of work, other significant factors affecting splice performance were uncovered. Although not covered by the scope of this contract, a brief discussion is presented for the purpose of stimulating interest in what is considered other fruitful areas for improved splice performance.

Jan 1, 1976