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By P. J. Rowsell, M. D. Waller

Paper presented at a meeting on: Artificial intelligence in the minerals sector, held in Nottingham, UK, 20 April 1993. The applications of artificial intelligence systems in the upstream petroleum industry are reviewed. Particular emphasis is placed on current and potential applications in drilling engineering. Several recent advances in drilling technology have led to a large increase in the quality and volume of data available. This combined with the escalating cost, particularly of off-shore operations, is testing the traditional reliance on the skill and judgement of rig operators. AI systems offer enormous scope in enhancing and aiding the performance of these operations

Apr 1, 1994

By T P. Fischer, S N. Williams, N C. Sturchio

Chemical and isotopic analyses of fumarole gases from Galeras Volcano, Colombia provide significant insights into the origin of volatile components in the magma. Water comprises a mixture of magmatic (rock-equilibrated at high temperature) and meteoric, with the relative proportions varying through time. Carbon isotopes are most consistent with a mantle source, although other contributions to the system cannot be ruled out. Nitrogen most likely originated from organic matter in subducted oceanic sediments. All of these 'primary' components have been modified somewhat by interaction or exchange with other reservoirs during ascent to the surface. In addition to information on the origin of the gases, these data show significant temporal variations precursory to eruptive events. Chemical ratios change and water becomes more meteoric in character prior to eruptions.

Jan 1, 1995

By John E. Tilton

Real copper prices during the past several decades display two striking characteristics. First, they are highly volatile. Within a year or two, copper prices can rise or fall by 30% or more. Second, over the longer term, they are falling. Indeed, since 1970, the secular trend price for copper is down by more than 50%. Figure 1 highlights both of these characteristics. It shows the average annual US producer price for copper since 1970 measured in constant 2001 US dollars. While the London Metal Exchange (LME) copper price is not shown, it and the US producer price have for some time moved more or less together. So pronounced short-run fluctuations around a significant long-run decline describe copper prices, not only in the United States, but around the world.

Jan 1, 2002

By J. B. Gwiazda

Introduction Thick seams constitute a considerable portion of Polish coal reserves. In producing mines and those under construction, the reserves where the height is more than 4.5 m (15 ft) total about 24% of all the hard coal reserves. The reserves that are under urban and industrial areas can be extracted using stowing methods for surface protection. About 50% of thick seam reserves can be extracted by caving methods. Thick seam mining methods Thick seams are usually extracted by multilift methods. There are some methods of thick seam mining that generally can be divided into caving and stowing methods. The stowing method is more expensive, but must be used when mining to protect surface features. The more known methods of thick seam mining include • extraction of thick seam in ascending order with stowing ; • thick seam mining in descending order with consolidated stowing; • thick seam mining with gob consolidation; • thick seam mining in descending order with roof caving ; • sublevel caving thick seam mining system; and • thick seam mining system using an artificial roof. Thick seam mining with introduction of an artificial roof The most advantageous method of thick seam mining is the method using an artificial roof. The artificial roof usually consists of wire mesh. Such wire mesh must be durable and must prevent small rock fragments from passing through. The mesh is usually made of steel properly protected against corrosion. The artificial roof is placed on the coal floor of the top slice (Fig. 1). Caving rock falls on the artificial roof and is thus separated from the coal. The next slice is extracted under the artificial roof. The producing face of the next slice must progress within 10 m (33 ft) behind the front of the first slice. As the second producing face progresses, the wire mesh moves down on the coal floor and may be used as an artificial roof for the next slice. Thus, one artificial roof allows the extraction of several consecutive slices. Application of the artificial roof allows for clean extraction and reduces coal losses. It also eliminates the hazard of spontaneous combustion. Introduction of the artificial roof has been limited due to a lack of artificial roof laying equipment. Manual laying of wire mesh is a labor-intensive operation, and it delays face progress, resulting in poor productivity. To eliminate these problems, artificial roof laying equipment was designed at the Polish Central Mining Institute. The support and the method of laying operation is covered by a patent. Artificial roof laying powered support To extract thick seams using an artificial roof, four-leg shield supports with lemniscate linkage were developed (Fig. 2). This shield is used in the first top

Jan 3, 1987

By A. H. Winckers

"The San Nicolás deposit is a complex fine grained polymetallic volcanogenic massive sulphide deposit located in central Mexico.Metallurgical testwork was carried out in 1999 and 2000 to develop a flowsheet. During the course of the metallurgical testwork it became evident that it would be impossible to develop an accurate head gradehecovery based model for the projection of metallurgy. It was suspected that variability in mineral texture was a predominate factor affecting metallurgy. For this reason it was decided to evaluate the applicability of QEM*SEM technology to this test program.This paper summarizes the metallurgical testwork and describes the evaluation and subsequent application of the QEM*SEM technology to characterize the mineral texture throughout the deposit. Finally it is shown how the QEM*SEM data are used in the mine block model to project the metallurgy.The QEM*SEM (Quantitative Evaluation of Minerals by Scanning Electron Microscopy) is an automated image analysis system developed by CSRO which provides quantitative numerical estimates of the compositional and textural properties of the mineral suite which govern the concentration process.INTRODUCTIONThe San Nicolás deposit, was discovered in 1997 through the application of geological and geophysical techniques. The property lies 60 km southeast of the city of Zacatecas on the central Mexican plateau as shown in Figure 1."

Jan 1, 2002

By Michael Stanwood

Project feasibility no longer involves just technical and economic viability-today's feasibility study must include environmental, regulatory, and political considerations as well. While the US now appears at least somewhat committed to developing synthetic fuels, including oil shale, it is the environmental issues, rules, regulations, and guidelines that will play the major role in determining the timing, magnitude, and overall scope of synfuel development in the coming years. The key environmental obstacle affecting oil shale development is uncertainty. Although oil shale may be the most environmentally studied "new" technology in the world, little is known with much degree of certainty about potential environmental consequences of one full-scale commercial facility, or the effects of a massive development effort in a relatively pristine and sparsely populated area. Other primary environmental uncertainties include: • Environmental compliance costs and their effects on investment decisions; • The reliability and acceptability of anticipated pollution control technologies; and • The confusing, time-consuming environmental regulatory framework, which requires more than 100 permits, clearances, and reviews before development occurs. This discussion will focus on the latter uncertainty, and will describe he current status of potential constraints to oil shale industry development in five areas: water availability; water quality degradation; air quality degradation; reclamation and spent shale disposal; and community impacts.

Jan 1, 1981

By M. G. Maruma

The effect of the amount of cold reduction and annealing temperature on the evolution of the texture of AISI 441 steel is reported. The steel was cold rolled by 62%, 78%, and 82%, followed by isothermal annealing of each sample at 900°C, 950°C, and 1025°C for 3 minutes. The crystallographic texture was determined by Phillips X?Pert PROMPD texture diffractrometer. Microstructures were characterized using optical microscopy and scanning electron microscopy (SEM).The results show that sample that received 78% cold reduction and annealing at 1025°C presented the highest Rm-value and lowest ?R-value, which would enhance its deep-drawing capability. In addition, this sample showed the highest intensity of shifted ?-fibre, notably {554}<225> and {334}<483>. It can therefore be concluded that the ?-fibre, which favours deep drawing, is optimal after 78% cold reduction and annealing at 1025°C.

Jan 1, 2013

The Manto Verde mine is found in the coastal ranges of the Atacama desert, 1000 km north of Santiago, Chile . The deposit is a fault-breccia specularite-oxide copper mineralisation hosted by the Jurassic andesites of La Negra Formation. It is located in a tensional fault that joins twoparallel arms of the Atacama Fault. The mine is in feasibility study: reserves are of the order of 60 Mt at 0.9 wt per cent soluble copper; mining will be undertaken at a rate of 11 000 tpd utilising an open pit and the ore will be heap-leached with acidified sea water, with copper recovery and by SX/EW.

Jan 1, 1992

By J. L. Potter

An inert-gas fusion technique was applied by the Bureau of Mines to the oxygen analysis of mixed-fluoride electrolytes used in electrowinning uranium and the rare-earth metals. Method development included: (1) Thermodynamic and experimental evaluation of the temperature required to quantitatively remove oxygen from a fluoride melt; (2) installation of a water and an acid trap to entrain the volatilized fluorides; (3) development of a suitable sample-preparation technique for the heterogeneous fluoride baths in which both pulverizing and pelletizing were necessary to achieve reproducible results; (4) comparison of platinum flux and dry crucible techniques, which showed that the use of platinum was not necessary. The accuracy of the method was evaluated by analyzing fluoride baths containing known amounts of oxygen added as the metal oxide. In the 0.05-to 0.5-percent range, the relative error was about ±5 percent.

Jan 1, 1962

In this paper, three types of value-adding in the minerals industry are discussed: downstream processing, improving the efficiency of existing processing and increasing the knowledge base and expertise of the staff. It is shown that, while downstream processing seems to offer a good way of improving Australia&apos;s trade position, there are a number of impediments to such development, notably, limited access to the appropriate technology and overseas markets. Transport costs can also be a problem. To reverse the situation will require more positive policies by government. In the meantime, something can be done towards adding value by increasing the efficiency of existing processes. Examples are given, showing how it might be possible to make economies in reagent costs in the gold industry, how innovative technology has led to more complete processing of a tailings dump, how research might lead to an increase in the throughput in the production of synthetic rutile and how it is possible to leach selectively from gold/copper ores.

Jan 1, 1995

By M. J. Scoble, L. M. Daneshmend, C. Hendricks

Paper presented at a meeting on: Artificial intelligence in the minerals sector, held in Nottingham, UK, 20 April 1993. An attempt is made to relate emerging technologies to education and training requirements by examining the nature of the Canadian mining industry's human resources. Particular attention is given to the trends evident in mine automation and their likely impact on instructional needs. The characteristics of "computer-aided instruction" systems are reviewed and related to the implementation and support of mine-wide monitoring and communication networks, which are seen as fundamental to the eventual automation of underground hardrock mines

Apr 1, 1994

A genesis based on new developments in the physical chemistry and flow properties of colloidal substances is proposed for the pipe-like Peko orebody. The rheological behaviour of sediments is governed by the contained colloids. Remobilization of thick pasty sediment during diagenesis is regarded as an essential step in the concentration of metal dispersed in sediments. At a high concentration the sediment pore fluid is a dense gelloid such that van der Waals attractive forces between the colloidal particles exceeds the coulombic repulsion. This permits accretion of the colloids into globular clots and their fracture fragments. These have a uniform size distribution dependent upon the rate of shear, and the sediment lithifies to clotted, porphyry-like, &quot;gritty&quot;, dolomitic or igneous-looking intrusions and flows. The physical chemical properties of natural sediment colloids appear adequate to account for ore formation.Adsorption accounts for the dispersion and retention of metal in sediments. Accretion accounts for the segregation of the colloidal materials to give the various types of clotted igneous-looking intrusive source rocks. Syneresis enables the colloids to spontaneously draw together and to dehydrate. Formation of an ordered lattice achieves a lower energy state and desorbs metals and insoluble metal compounds &quot;particle by particle&quot; into the escaping water of hydration and pore water. Peptization enables migration of the metal hydrosols as stable dispersions until they merge for outflow through seepage zones or water extrusion channels. Nucleation and concretion precipitate the metal dispersoids from pore waters seeping through hydrous parts of the source rock, porous beds, faults, and zones of weakness by which the connate waters leave the lithifying sediments. Gelatinous precipitated mineral matter in the ore channels is capable of thixotropic reliquefaction when disturbed by shock or movement. Local reintrusion, flowage, interveinings,brecciation, and intermixing of the materials is the result.The principles of the suggested genesis are applicable to both syngenetic and epigenetic mineral accumulations.

Jan 1, 1966

By L. A. Cramer

Platinum metal was first utilized by the Inca civilization in South America where it was found in alluvial deposits along the San Juan and Atrato rivers that lie between the Andean mountain range in Colombia and the Pacific Ocean. The nuggets found in these rivers average between 77% and 86%platinum, 7%?8% iron and small amounts of copper, gold and other Platinum Group Metals (PGMs). The Incas often alloyed platinum with copper to increase its workability and fabricated various ornaments from it.

Jan 1, 2001

By V. J. Sikora, W. J. McGuire

Several years ago, we used an electric analogue computer to study the effect of vertical fractures on the productivity of wells in expanding fluid-drive reservoirs. The results of this work were used both as a guide to research and as a basis for the design of actual fracturing operations. In 1958, Dyes, Kemp and Caudle&apos; published portions of the data from this study. The results were released in 1959 to service companies for use in fracturing guides. The purpose of this note is to discuss the experimental conditions and assumptions which were made to derive the information which is already partially a matter of public record. ASSUMPTIONS This study applies to fractures which extend in a vertical plane symmetrically from the well. For simplicity, we chose to study the case of a well in a square drainage area with its fractures extending toward two of its nearest neighbors. We have assumed no migration of fluid across the boundary of this area. The quadrant shown in Fig. 1 models this system. We made the usual assumptions that the reservoir is homogeneous and isotropic, that the fluid is homogeneous and that production is effected by fluid-expansion drive. We also assumed that the fracture extends from top to bottom of the reservoir. Of more practical interest is our assumption that the fracture does not change the size of the drainage area. This premise is appropriate if all the wells in the reservoir are fractured in the same way. But where a single well is fractured, its drainage area may be enlarged at the expense of its neighbors. This could be of economic importance. The assumption that the fracture will not extend beyond the established drainage area of the well also limits the application of the results. Such long frac- tures will yield benefits in excess of those predicted here. When we assume homogeneity, we disregard the frequently observed zone of damage in the vicinity of the well. Where damage is severe, the benefits resulting from by-passing it will far exceed those predicted by this study. All comparisons were made of systems producing in the semi-steady state. By this we mean that equal volumes contributed equally to flow (pressure was dropping at a uniform rate throughout the system) when the rate of flow was observed. EXPERIMENTAL SET-UP We used the pool unit of an electric analyzer&apos; in this study. The squase drainage system of a well was rep-

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Jan 1, 2009

By Holly J

The period following World War II has seen many changes in stoping techniques at The Great Boulder Gold Mine. The new methods resulted in improved unit production figures, and have given some relief from the rising worldwide cost spiral in the post war years.Significant production figures are shown graphically in...

Jan 1, 1956

By Robert Boyd

The Diamond Markets ? Supply has continuously increased over the past 25 years ? However, global supply is expected to drop by 1 to 2% by 2015 ? Demand Driven Market ?Demand is expected to grow 3% annually through to 2015 ? Supply Squeeze Anticipated (2010 to 2015) ? Consumption is exceeding rate of discovery, mine development and reserve replacement ? These fundamentals are driving increased capacity and production at existing mines in South Africa, Botswana and Russia and new areas such as Canada ? Canada is now the third largest diamond producing country in the world ? These fundamentals are also driving record levels of exploration expenditures throughout the world with particular focus on Africa and Canada

May 1, 2006

By Xuan Li

Aluminum slag is generated when aluminum metals are recycled through a smelting process in the presence of salt. There are small amounts of aluminum metals trapped in the aluminum slag. This research aims at evaluating the use of aluminum slag as an expansion agent for the production of lightweight concrete by taking advantage of the residual aluminum metals in the slag. The research identified key elements of producing lightweight concrete products through utilizing various mixture components including sodium hydroxide (NaOH), lime (CaO), cement, and gypsum. The volumetric expansion rate was investigated and the density and strength of the products were determined. The results show that aluminum slag can be utilized for the production of lightweight concrete products.

Jan 1, 2010

"The Crescent, DM, and Pothook zones are copper-gold porphyry deposits which formed in association with alkalic intrusions of the early Jurassic Iron Mask batholith. The characteristics of the Crescent and DM deposits are nearly identical. Both formed along the contact between the Cherry Creek monzodiorite and Pothook diorite phases of the batholith. Permeable intrusion breccias along the contact concentrated the flow of hydrothermal fluids. Early, pre-ore alteration is represented by pervasive, sulphide-barren potassium metasomatism. The precipitation of copper-gold ore occurred during subsequent fracture-controlled potassic alteration, and is most strongly developed in chlorite-sulphide veins and their alteration envelopes. A central zone of potassic alteration is surrounded by a propylitic, pyritic halo in both deposits. The DM zone is unique among alkalic porphyry deposits in its high abundance of quartz-sulphide veins.The Pothook deposit formed at the westernmost contact of the Iron Mask batholith with enclosing Nicola Group volcanic rocks. Pervasive potassium metasomatism, similar in style to that at Crescent and DM, is associated with intrusion of the Cherry Creek monzonite. Pervasive and fracture-controlled albitic alteration is associated with intrusion of the Sugarloaf diorite and introduced minor copper-gold mineralization. Most of the copper-gold mineralization was introduced during formation of veins and breccia matrices dominated by magnetite/hematite and sulphide. Late-stage chlorite veining may have remobilized or introduced additional gold mineralization.Copper and gold assays in the Crescent deposit are well-correlated and have a nearly constant Cu:Au ratio, suggesting that the metals coprecipitated during a single hydrothermal event. In the Pothook deposit, copper and gold do not correlate closely, lack spatial correspondence, and suggest that transport and/or deposition of the two metals were not identically controlled and that they may have been introduced at different times by separate hydrothermal events."

Jan 1, 1995

By Lutz Markworth, Evren Ören

"The worldwide demand of ores and the depletion of the high-purity deposits make it necessary to recover ores in increasingly finer size fractions in the feed material. The flotation technology of more than 40 years old plants was not able to recover the ultra fine material. Those slurry tailings ponds now have the chance to be re-processed with PNEUFLOT® technology.The bubble sizes of different flotation technologies have a huge influence of the results especially regarding the recovery of the ultra fine particle sizes.PNEUFLOT® technology of HUMBOLDT WEDAG Coal & Minerals Technology GmbH in Germany was applied to ultra fine Phosphate, Copper and Platinum ores. The results will be presented in this paper.Conventional technology like agitator flotation has its limits in the flotation of fines due to turbulences in the cell. The position of the agitator influences the recovery of the fines. A deep impeller generates a higher froth zone. This helps to catch the medium fines. Due to the static head of the slurry inside the cell, compressed air is required for such cell designs.Column flotation is well known for a good selectivity without having in the first cell a good recovery. This leads to invest in several cleaning stages to reach an acceptable recovery. Further more, compressed air is required to generate the air bubbles to the flotation process, which are much bigger than with PNEUFLOT® technology applied.INTRODUCTIONHigh metal prices are actually the basis to invest in poor deposits or deposits with very fine intergrown ores which have to be milled down to ultra fine powders less than 60 micron. The liberation grade has to be determined by a mineralogical analysis. Polish sections have to be prepared and interpreted by using of a microscope. Figure 1 and figure 2 are showing polish sections of a platinum-nickel ore from Petchenga Nickel at Zapolyarni Mine in Russia. The head grades for rich ore are for copper between 0.05 – 0.15%, for nickel between 3 – 7% and for platinum group minerals approx. 0.15 oz/t. With an efficient flotation technology it can be upgraded to 20 oz/t."

Jan 1, 2009