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By Cyrus W. Field

Metalliferous sediments constitute an important component of the sedimentary veneer that overlies basaltic oceanic crust of the Nazca Plate and elsewhere. Although first collected more than one century ago near the East Pacific Rise during the Challenger Expedition and recognized for their anomalously high content of Fe and Mn, occurring as very fine-grained, yellow-orange, oxides, hydroxides, and oxyhydroxides, it was not until the more detailed studies of Bostrom and Peterson (1966) that their geologic significance and concentrations of other transition metals were fully appreciated. The Nazca Plate is a dynamic lithospheric unit bordered by the Peru-Chile trench and the East Pacific Rise to the east and west, and by the Galapagos Rift and the Chile Rise to the north and south (Fig. 1). Samples employed in this study were taken from piston core recovered from the Nazca Plate (Fig. 2), D. S. D. P. drill core from the northeast Pacific (Dymond and others, 1973), ferromanganese nodules from dredge-haul s at several locations, and from hydrothermal mineral deposits of the Andes. Our efforts have been largely sponsored by the National Science Foundation through its International Decade of Ocean Exploration Pro- gram. The metalliferous fraction of these sediments is widespread, but generally small. Sedimentation is dominated by biogenic silica in the equatorial latitudes, terrigenous debris adjacent to the South American Continent, and by biogenic carbonate elsewhere, except at depths below 3500 m in the central and northwest parts of the Nazca Plate near the East Pacific Rise. Contributions of these distinctive sediment types are shown by the distributions of Si02, A1203, and CaC03 given in Figure 3.

Jan 1, 1982

Mining is big business in Ontario. The province is Canada?s leading mining region. It consistently ranks among the top 10 jurisdictions worldwide for exploration spending, reaching about C$1 billion in 2011. More than 26 percent of all exploration and appraisal dollars spent in Canada are invested in Ontario. Minerals produced include nickel, copper, platinum group elements (PGE), cobalt, zinc, diamonds, gold and silver. It was reported that there are more than 600 mining exploration projects in the province. And, recent discoveries of chromite in northern Ontario?s Ring of Fire will add to the province?s mineral production in the coming years.

Jan 1, 2013

By Yessica Idrogo

"Undoubtedly mining is currently the activity that brings a great development for all countries involvedin this industry, which means that to develop mining requires adequate explosive mixtures. The following work about AL/AN/FO is presented, knowing that this is a dry blasting agent, which iscomposed by ammonium nitrate, petroleum diesel N°2 and aluminum (AN, FO, AL). It is known that this dry blasting agent AL/AN/FO was invented by A. Baver Ph. D. in Marcona Mining Company, 12/12/1968, where in that investigation also worked Carlos Agreda Ph.D. as assistant of the mentioned inventor."

Jan 1, 2017

By Christoph Mueller

Mining operations are characterized by cost pressure and cycling product prices. A high potential for enhancing efficiency is the integration of all single steps of the mining working chain into a production process structure to make advantage of an optimized flow of material and information through the ?moving ore factory?. As modern mining machinery today is controlled electronically and even already operated autonomously, a smooth and cost efficient flow of data in the mining process will be crucial for cost efficient future mine operations. Therefor, the International Rock Excavation Data Exchange Standard (IREDES) was launched by major players in the industry. The task of this initiative is to define a ?common electronic language? for easy and standardized data exchange between mining machines and central computer systems. As in other industries, this standard is expected to have significant impact on the use of automated equipment. It shall provide easy ways of using multi vendor machine installations in data controlled mining processes. At the same time it reduces cost for individual development of interfaces for all parties involved. Standardized data exchange is also a crucial precondition to integrate the mining process into enterprise level modeling, cost analysis and decision finding systems. The standard?s technical architecture is open and flexible for future applications. It uses modern XML technology enabling easy data exchange with commercial databases as well as open on line networking. The IREDES work is carried out by the initiative members working jointly together in the technical work groups. Prototyping implementations of the Drill rigs profile are currently going on. Further profiles under development cover LHD?s/Loaders/Trucks and Explosives Chargers. The first official release covering the Drill Rigs profile is planned for the end of 2002.

May 1, 2002

By M E. Webb

Safety is a key value in most leading mining companies. Despite years of effort, and significant expense in ‘programs’, operating sites seem to have been left with no real improvement in either the elimination of fatalities or sustained reduction in injuries.Safety systems and processes have grown and evolved, often to the point where they have become overly complicated and marginally useful.MMG Limited, following the consolidation of its Australian operations under a single management structure, undertook a program to effect real and sustained change in its approach to managing safety. The program aimed at improving safety by better engaging its workforce and by making safety processes simple, useful and effective. It defined the role of the supervisor in creating safe work, the role of the people doing work and the role of safe work methods.A safety diagnostic tool was developed to assess site against safety-critical mindsets, behaviours, cultures and systems. The outcome of the diagnostic is considered by the organisation to be the true lead indicator of safety performance.While still a work-in-progress, the program at the Australian Operations of MMG Limited shows that challenging common paradigms in safety management can create real change in safety performance.CITATION:Webb, M E, 2016. Making safety simple, useful and effective, in Proceedings International Mine Management Conference, pp 217-223 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By W. V. Mutler

Present day capital costs are analyzed for a 2,000 metric tonne per day (MTPD) pyrite burning plant and compared with a sulphur burning plant of the same capacity. Power, raw material and steam production rates are then compared for the two facility types. A sensitivity analysis is conducted to highlight the impact changing sulphur, pyrite, capital and operating costs have on the relative economics of these feeds. Technological improvement effects on capital cost and energy recovery are also discussed. Besides the steam produced from the burning of pure sulphur or pyrite, plants using an advanced form of heat recovery can produce up to 10 bar steam using heat from acid formation. The quantity depends on the overall water balance which is influenced by such factors as gas strength and product acid concentration. Modern materials and innovative process design also improve the ability to increase the high pressure steam from the roaster boiler in pyrite plants above the traditional 1.25 kg of superheated steam per kg of acid produced.

Jan 1, 2009

By Melvin P. Silverman

The literature on methane-oxidizing bacteria is reviewed in regard to (1) the growth and isolation of cultures by special techniques; (2) the distribution of these organisms in nature and descriptions of individual species; (3) the physiology of methane-oxidizing bacteria as influenced by temperature, light, pH, aerobiosis versus anaerobiosis, and carbon and nitrogen sources; and (4) the biochemistry of methane oxidation revealed by studies with intact cells and subcellular systems. Present practical applications of methane-oxidizing bacteria are limited to prospecting for natural gas and petroleum deposits. Desirable areas for future research are discussed as well as some possible applications such as (1) the removal and/or early detection of methane gas in coal mines by intact culls or enzyme preparations; (2) the generation of electrical energy by microbial fuel cells using methane as fuel; (3) the growth of methane-oxidizing bacteria on methane fur their food value; (4) the purification of hydrocarbon gas mixtures using methane-oxidizing or other alkane-oxidizing bacteria; and (5) the synthesis of methane from mixtures of H2 and CO or H2 and CO2 by methane-forming bacteria.

Jan 1, 1964

By Melvin P. Silverman

The literature on methane-oxidizing bacteria is reviewed in regard to (1) the growth and isolation of cultures by special techniques; (2) the distribution of these organisms in nature and descriptions of individual species; (3) the physiology of methane-oxidizing bacteria as influenced by temperature, light, pH, aerobiosis versus anaerobiosis, and carbon and nitrogen sources; and (4) the biochemistry of methane oxidation revealed by studies with intact cells and subcellular systems. Present practical applications of methane-oxidizing bacteria are limited to prospecting for natural gas and petroleum deposits. Desirable areas for future research are discussed as well as some possible applications such as (1) the removal and/or early detection of methane gas in coal mines by intact cells or enzyme preparations; (2) the generation of electrical energy by microbial fuel cells using methane as fuel; (3) the growth of methane-oxidizing bacteria on methane for their food value; (4) the purification of hydrocarbon gas mixtures using methane-oxidizing or other alkane-oxidizing bacteria; and (5) the synthesis of methane from mixtures of H2 and CO or H2 and CO2 by me thane-forming bacteria.

Jan 1, 1964

By C. P. Browning

Copper, as far as we know, was the first metal used by man, and due to the fact that it occurs in many places in the 'native' state, and also to the ease with which it may be shaped, it has played an important part in the evolution of civilization. Copper tools with inscriptions dating back to 6,000 B.C. are known in Egypt, where the metal probably got its start as a useful material in human hands. Just how far back the use of copper in Canada dates is difficult to say, but it was in use by the Indians in the Lake Superior country long before the arrival of the first white man. For many generations the Eskimos also have used copper derived fr0m deposits of the native metal found in the Coronation Gulf district. Due to the metal's many unique qualities, imperishable with age, ancient implements and utensils are apparently as good today as when they were made, having withstood the onslaught of time probably better than objects of any of the other base metals. Copper alloys so well with other metals that today it is second only to iron in its industrial value. Even at the beginning of the eighteenth century the world's production of copper was probably not more than seven thousand tons a year, with Great Britain producing three-fourths of this. One hundred years ago the mines of the United States, Chili, Mexico, Canada, South Africa, Australia, and Tasmania, which now produce about nine-tenths of the copper of the world, were totally undeveloped. Ln 1926 the world production of copper was approximately 1,658,000 tons, which was seventy thousand tons greater than in the preceding year; but growing demand absorbed the increased production, so that the stock of rough copper throughout the world is comparatively small. Of this huge tonnage of the metal, Canada produced four percent, two-thirds of it emanating from British Columbia, nearly one-third from the Province of Ontario, and the balance from Quebec.

Jan 1, 1927

By J. Yuan

Ground calcium carbonate (GCC) and chemically precipitated calcium carbonate (PCC) have become important mineral-based commodities in recent years. GCC manufacturing generally requires high purity and high brightness deposits of marble, chalk or limestone as the stone source. PCC usually uses limes made from lesser quality limestone deposits. GCC products have a wide span of particle size, with a d50 size ranging from sub micrometers to as large as several inches such as those used in landscaping. PCC products are typically limited to less than 10 µm (1,250 mesh). Each PCC product has a narrowly distributed size range. GCC and PCC products tend to have higher levels of whiteness com-pared with other traditional filler and extenders, such as kaolin and talc. Published statistics of GCC production volume often vary due to the exclusion of certain size range GCC products. According to Roskill’s latest estimate, world GCC capacity was believed to exceed 56 Mt (62 millionst) during 2004 for all grades.

Jan 1, 2005

By Neil B. Prenn

Mine Development Associates, Inc. was formed in March of 1987 to provide mine engineering assistance to the mineral industry. To be competitive with other firms, Mine Development must be able to provide quick and accurate ore reserves and mine plans for clients. Commercially available mining software was necessary for Mine Development to assist the client. This paper describes how Mine Development chose mining software, the time involved in getting up to speed, and several case histories of how the software is used. The case histories discussed include: * 3,000,000 ton gold deposit in Nevada. * 5,000,000 ton gold deposit in South Dakota. * 1,000,000 ton gold deposit in Australia. * +100,000,000 ton gold deposit in Nevada. * 25,000,000 ton carbonate deposit in California.

Jan 1, 1989

By J. Q. McNatt

Mr. President and Members of the Rocky Mountain Coal Mining Institute: It is a great pleasure to be with you at this meeting, to enjoy the entertainments, and the good fellowship of all present., as well as to become better acquainted with the men in general. In presenting my subject today, .1 feel like the darky, who was home-, ward bound, had become weary and sat down by the wayside to rest. Presently glancing about to view the scenery, he spied a. large brown bear slowly coming down the path scenting his tracks one by 'one as he advanced. The darky to be polite said, "Mr. Bear, I see you like my tracks, I will make you some more." I have on. a few occasions given some interesting information on the various subjects such as The Prolonged Famines of Arabia, Movements and Migrations of the Races of Men, Life Indications on the Planet Mars, and today I have come before you with a new step in the roadway-Coal Geology. It is sometimes difficult to interpret the geological processes so as to be understood intelligently, but it shall be my aim to make this as plain as possible.

Jan 1, 1927

By T. N. McVay

The Bureau of Mines has developed a field test for detecting the presence of columbium in a variety of minerals containing the clement. The test consists of fusing the mineral or rock powder with potassium pyrosulfate in a porcelain crucible, digesting the melt with hot dilute hydrochloric acid to release the columbium oxide (Cb205), and subsequently reducing the columbium oxide to a lower oxide by adding tin, which gives a blue color to the contents of the crucible. The method will detect 1 percent of contained columbium oxide (Cb205) in a mineral sample provided no tungsten is present. If a mineral containing appreciable titanium is test,-!d in the same manner, the solution in the crucible becomes violet. In the presence of columbium, titanium at first causes a violet coloration of the solution, which after a few minutes is masked by the stronger blue of the reduced columbium oxide. Although tantalum oxide (Ta205) does not interfere with the columbium test, tungsten gives a blue color that is indistinguishable from the color obtained with columbium. A simple method is available to detect the presence of columbium in the absence of tungsten, but when the presence of tungsten is suspected, the sample must be subjected to somewhat more elaborate chemical tests to determine the presence or absence of columbium. Although these latter tests can be made in the field, several steps are involved that arc best performed in the laboratory with simple equipment.

Jan 1, 1962

By Charles V. Jenkins

The structure of steel, when rendered coarse by over-heating, is made fine by re-heating to a certain temperature, the determination of which has received much attention from eminent metallurgical authorities. Among these, I may particularly mention Prof. D. Tschernoff' [Chernoff], who, about thirty years ago, studied this question in connection with his investigations on the structure of steel in genera1. † Some years later, Mr. J. A. Brinell took up the inquiry, and arrived at many important conclusions, stated in his well-known rules on the treatment of steel. ‡ These two gentlemen, however, based their reasoning chiefly upon the aspect of fractures—a method which, though it affords valuable information, does not readily reveal the different steps by which a change in structure takes place. For further light on the subject, we owe much to more recent microscopic investigations, which have made us better acquainted with the internal structure of metals. Such an investigation, closely connected with the present subject, and made by Mr. John E. Stead a few years ago, was first published in 1898.6

Jan 1, 1903

By R. D. Brown

In his March 31, 1977 budget, Finance Minister Macdonald has attempted the delicate balancing act of stimulating the economy without reinforcing the inflationary pressures which Canada is continuing to experience. Several tax changes of benefit to the mining industry, as well as measures designed to encourage oil exploration in frontier areas, are among the budget proposals. Additional earned depletion of 66- 2 /3 %, which may be offset against income from any source, will be available on drilling costs in excess of $5 million incurred between March 31, 1977 and April 1, 1980 in connection with an exploratory well in Canada, including the continental shelf . Other changes include more favourable treatment of resource property dispositions, less restrictive rules r elating to "successor corporations" , increased capital-cost allowance on railway spur lines, the inclusion of certain production royalties in Canadian development expenses and the application of the lower "manufacturing and processing" tax rate to sulphur production. To encourage business capital spending, the 5% federal investment tax credit it to be extended an additional three years to mid 1980 and broadened to include spending on scientific research and development. The rate of credit will also be selectively increased on a regional basis, to 7.5 % in certain designated areas in Saskatchewan, Manitoba. Northern. Ontario and Quebec, and to 10% in the Atlantic provinces and the Gaspe.

Jan 1, 1977

By R. L. Grant

[p(,ton~to'rs 'ar-IV uscG.. to explode 9crnli .... sible c}:plosivcs, dynamites, or other hiGh uxplosives. This ?,...!xplosion or detr)nation is brought about by th\.:J energy which i liberated as a cOl":"Lb' nation of concusBion and heat wl1en the ? detonator is fired. 'm Ot:18t? I'l(jrds~ liThe detonator is the key VI: ich unlocks the enerGY of a llgh? explosIve""? (8) :1/. Being sensitive nd latently dangerous, detonators ITl.ust lTIeet t\V0 primary requirerDentr: They must be ..;.afe to handle and IT. list? detonate' when (l,esired, the ... eby iIr.parting deton:l.tion to the explo8ivc cJ.1Cire-e.]

Jan 1, 1941

By Milton Blander

"A review of concepts and theories for predicting thermodynamic solution properties of multicomponent high temperature liquid solutions is reviewed. During the last 50 years the ability to predict such properties for molten salts, silicates and metals based on the generally known properties of the lower order (often binary) systems has been developed and shown to provide predictions which are quite useful in science and technology. There are many gaps in our understanding of these high temperature solutions, especially for metals, and considerably more work is needed.INTRODUCTIONA number of solution theories and concepts have been developed which reliably predict the properties of multicomponent solutions from those of the lower order systems (often only the binaries). Because there is available data for a large fraction of the important binaries, the capability for making predictions for many multicomponent systems used in metallurgical separation processes is broad and potentially very useful. At the very least, the theories greatly minimize the data necessary for predicting properties of complex multicomponent solutions of molten salts, silicates and metals. It is the purpose of this paper to discuss the concepts which are demonstrably useful. We will discuss simple forms of the theories to make the concepts clear but we will refer to the publications which contain the more complex equations needed to treat the large majority of systems.A simple framework for understanding what we need to know in order to make technologically useful predictions is based on well known thermodynamic principles. In technologies and sciences where molten salts, slags magmas or molten metals are used or studied, one must often calculate the extent of a chemical reaction (or separation) or of phase changes. To do this, one must first write an equilibrium constant, K, for the reaction in terms of the standard free energy change of the reaction, ?G°."

Jan 1, 1996

By Jr. Napolitano, Jr. Sanders

"Morphological evolution of a dendritic growth front in a binary alloy is simulated using a cellular automaton approach to establish the feasibility of modeling such growth with a local rule-based scheme. The motivation for this work is derived from the need to predict the development of solidification structures within real components of complex geometry, where significant constraint of the thermal and solutal fields may exist. Such cases present complex boundaries and large domain sizes, which may preclude the effective use of more conventional methods. In this work, a model is presented which couples a two-dimensional alternate-direction-implicit finite-difference diffusion solution with a cellular automaton growth algorithm to simulate morphological evolution in alloys solidifying under directional growth conditions. Temperature, composition, and interface curvature are incorporated into a local growth potential which is used by the automaton, allowing the interface to evolve. Alloy solidification is simulated over a range of experimental conditions, producing various structures. Issues addressed include morphological instability, primary spacing selection, interface curvature, microsegregation, and tip conditions.IntroductionThe development of dendritic structure plays an essential role in alloy solidification. Virtually every microstructural feature, within a cast alloy component, is related to the interface morphology present during solidification. Conventional solidification theory, describing dendrite tip kinetics and mushy zone phenomena, provides a means for estimating overall microstructural parameters for an alloy solidified under steady-state conditions. Microstructural prediction for actual components, which are finite in size and complex in geometry, requires a description of the evolution of the interface morphology under transient conditions and geometrical constraint and an understanding of how the structure propagates through the mold. Any useful simulation tool must be equipped to handle these circumstances within the limits of computational feasibility."

Jan 1, 1998

By Kazuyoshi Shimakage, Shinji Hirai, Kenji Wada

"An amorphous zirconium oxide coating was prepared by the sol-gel process using zirconium tetra-n-butoxide on the surface of aluminum to improve the corrosion resistance to salt, acid and alkaline attacks. The coating films formed on the smooth aluminum substrates under UV-irradiation indicated an excellent corrosion resistance for salt, acid and alkaline attack tests. For example, the corroded area of coating film in salt attack test for 3600ks in the order of sol-gel coating· film< chromate film <boehmite film, and the sol-gel coating film had the best corrosion resistance. The coating film prepared on the coarse aluminum substrate by a boiling treatment after heat treatment at 573K also had greater corrosion resistance, and a water-avid surface appeared a contact angle of approximately 3°.IntroductionAs given in a previous paper1; a composite film consisting of a porous layer of anodically grown aluminum oxide filled with amorphous zirconium oxide and an amorphous zirconium oxide coating layer deposited thereon via the sol-gel process utilizing the dip-coating technique, was prepared to improve the alkaline corrosion resistance of aluminum. The alkaline corrosion resistance of these composite films was increased in the range of 24 to 50 times those of conventional anodic oxide films anodized in sulfuric acid. As a result, it was proved that heat treatment at 573K after dip-coating was an important process to .remove organic component from gel film and to accelerate the densification of coating layer. Furthermore, the effect of ultraviolet (UV) irradiation at ambient temperature on the densification of coating layer was also examined to lower the heat-treatment temperature2.Then, a sol-gel film prepared by UV irradiation at ambient temperature indicated that alkaline corrosion resistance of aluminum was superior in the range of 2.4 times to 2. 6 times that of the conventional composite film heated at 573K."

Jan 1, 2000

By A. A. Sobek

Controlled release systems delivering the required concentration of an effective bactericide over an extended time period have been developed by The BFGoodrich Company&apos;s ProMac® Systems group. The ProMac system is site-specific and includes a four-step approach to controlling acid mine drainage (AMD): (1) Diagnosing the problem, (2) Prescribing the treatment, (3) Supervising the application of controlled release bactericides, and (4) Honitoring the success of applied treatment. The success of the ProMac system is evidenced by improved water quality, healthy vegetation, a reduction in levels of acidophilic thiobacillus, and a corresponding increase in population of beneficial microorganisms.

Jan 1, 1986