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By Klaus W. John

The geologic factor of greatest significance in rock mechanics and rock engineering is considered to be the geologic structure represented by joints, faults, and other planes of weakness. This geologic structure differentiates between the rock element and the rock system composed of these elements. Only during the last decade has the difference of the technological properties of element and system been recognized but this appears to be more in theory than in engineering practice. If rock mechanics is to achieve real significance in engineering practice, it has to provide methods of analysis which are realistic compromises between the best representation of the actual conditions and pragmatic engineering. The rock mechanics practitioner has to face the fact that many geological engineering and rock mechanics problems may be too complex to allow rigorous analysis but at the same time are deemed satisfactory for the construction of major structures. Ultimately, the geotechnical engineer or the engineering geologist has to express the effect of geologic factors in quantitative, even if approximate, terms and provide numerical data on strength and deformability of rock systems to be utilized in construction. Qualitative evaluations, quantitative descriptions of geologic features as such, and comparisons of specific test results are always of interest but may not suffice as basis for engineering decisions and designs. The present efforts of the rock mechanics group at the Karlsruhe University, Federal Republic of Germany, are based on a systematic combination of geomechanical models and numerical analyses based on the finite element approach. This group considers that at the present stage

Jan 1, 1970

By Pedro E. Rengifo

Splicing methods have undergone considerable developments over the last 2Oyears. Continuous conveyor belt service is dependent entirely on the strength and life of the splice to hold the two ends together. Ultimately, belting performance is dependent on the quality, efficiency, and technique of the splicer. As customers demand better belting performance and running tensions increase, the need for splices that perform as efficiently as the belting has increased also. Higher dynamic belt constructions have also dictated the need for "new"sp1icing techniques. Regardless of the belt type used or spliced, one item that is most necessary with all belt types is the quality of the workmanship and standardized splicing methods that employ all of the necessary elements required to ensure reliable field service. This paper will explore the use of Goodyear-issued internal standards for field splicing following the constraints of quality and efficiency for fabric and steel cord reinforced belting. Also included are the 10 most common mistakes made by splicers, Goodyear-issued Field Quality Assurance Standards, and check lists for end users to adhere to the manufacturers' requirements for splicing including materials and specifications for conveyor belt splicing and repairs.

Jan 1, 2004

By Mark A. Rugen

It may be difficult to imagine but small engineering companies do exist, even in relatively large cities like San Antonio. Due to the limited capital available for the purchase or use of equipment such as computers, many times the small company must evaluate a blast damage claim by limited means. This paper will discuss how a relatively small company has managed to become the leading blast damage experts in an area without the use of computers or sophisticated equipment. It will be shown that a single individual in a company who is familiar with vibration theory, local soil conditions and who does not mind spending long hours with a calculator and reference books can satisfy both the insuranc e adjuster or attorney, and the homeowner concerning the claim. Several examples will be given which show the typical flow of work and the ultimate outcome. This paper will focus on the special problems encountered by a small firm and how these can be overcome, and the unique interaction of a small engineering firm with both the insurance adjuster/attorney and the homowner that can lead to an equitable settlement of the claim.

Jan 1, 1983

By Valentine R. Garflas

The Mexican oil fields, during 1921, produced in round numbers 203,000,000 bbl. of which 176,000,000 bbl., or 86 per cent., were exported, the bulk of these exports, or about 73.3 per cent., going to the United States. The Mexican exports were divided by grades as follows: Light crude, 47.0 per cent.; heavy crude, 22.0 per cent.; tops, 3.5 per cent.; fuel oil from light crude, 24.0 per cent. The balance, or 31/2 per cent., includes the bunker fuel shipments and the coastwise trade in Mexico, which is not classified as to grades. The figures show that, in importance, the light-oil fields form about 75 per cent. of the Mcxican petroleum industry. The production of the Panuco field has followed the general history of the American fields, and its gradual decline, which is at present foreshadowed, may be estimated as well as its ultimate economic life. On the other hand, the behavior of the light-oil fields to the south is unlike any in the world so far discovered, and as a result we have concentrated overproductions followed by sudden droughts, both sometimes equally unexpected. The coming in of two or three gushers within adequate pipe-line facilities will flood the market with 100,000 bbl. or more a day, while the flooding by water of a particular pool will, in a few weeks, remove from the market one-half the total production of the Mexican fields.

Jan 1, 1923

By E. A. Wieselmann

This chapter presents a successful approach for achieving mine entry stability at the Cane Creek potash mine by the utilization of closure measurements. The mine is located in southeastern Utah (Fig. l). Mining is being conducted at depths in excess of 3000 ft under structurally complex geologic conditions typical of the Paradox salt basin. The closure measurement systems described have definite application for determining relative entry stability in other nonelastic rocks which are similar in behavior to potash. Similar types of closure measurements have been taken in various underground openings throughout the United States, Canada, arid Europe. Application of this closure data has previously met with varying degrees of success as a tool for design of under- ground openings in both elastic and nonelastic media.1-32 Closure measurements can be made easily and economically and they provide a practical solutiori to a practical problem. They are in-situ measurements which do not necessarily require laboratory correlation. Simple closure measurements have special significance in potash because "steady-state" ' closure rate, or creep, of the entries is measured. These closure rates can be utilized because nonelastic media such as potash will never achieve absolute stability around a mine entry. The potash will tend to creep or deform until all entries are closed and the overburden stress is redistributed over what was previously the mine area. The time for this ultimate effect to occur is dependent on a number of mining and geologic variables. Percentage of mine extraction, mining

Jan 1, 1972

By Valentine R. Garflas

The Mexican oil fields, during 1921, produced in round numbers 203,000,000 bbl. of which 176,000,000 bbl., or 86 per cent., were exported, the bulk of these exports, or about 73.3 per cent., going to the United States. The Mexican exports were divided by grades as follows: Light crude, 47.0 per cent.; heavy crude, 22.0 per cent.; tops, 3.5 per cent.; fuel oil from light crude, 24.0 per cent. The balance, or 31/2 per cent., includes the bunker fuel shipments and the coastwise trade in Mexico, which is not classified as to grades. The figures show that, in importance, the light-oil fields form about 75 per cent. of the Mcxican petroleum industry. The production of the Panuco field has followed the general history of the American fields, and its gradual decline, which is at present foreshadowed, may be estimated as well as its ultimate economic life. On the other hand, the behavior of the light-oil fields to the south is unlike any in the world so far discovered, and as a result we have concentrated overproductions followed by sudden droughts, both sometimes equally unexpected. The coming in of two or three gushers within adequate pipe-line facilities will flood the market with 100,000 bbl. or more a day, while the flooding by water of a particular pool will, in a few weeks, remove from the market one-half the total production of the Mexican fields.

Jan 1, 1923

The development of the Australasian Code for Reporting of Identified Mineral Resources and Ore Reserves is a significan step towards informing the financial community and the public about the future profitability and risks of investing in resource companies. The Code is also important from the accountants' point of view because it provides them with a well-defined bash for assigning costs or attributing value to the assets of resource companies and hence improving their financial reports. Although reporting to the public is ultimately the responsibility of management, accountants, like geologists, are frequently required to provide information for inclusion in these reports. Jr the last ten years, there has been a considerable refinement in the reporting of mineral resources which can be attributed mainly tc the progress made towards developing the Code. It seems tha the classification and terminology that the geologists have developed are widely used in the annual reports. However, little progress has been made by accountants in improving the financia information. The purpose of this paper is twofold: (a) to outline briefl) some of the major problems in accounting and reporting fo; mining companies and; (b) to examine the potential contribution of the Code in solving those problems.

Jan 1, 1990

By Read Winterburn

This study of the relationship of the accumulation and drainage of oil to the structural conditions in the Wilmington oil field is presented with the hope that the data contained herein will aid in efficient exploita-tion of other fields where similar conditions exist. It is also probable that the conditions observed in this field will enable accurate comparisons of various well-spacing programs as to efficiency of production and ultimate recovery. Formations in Wilmington Field Age Formation Thickness Lithology and Remarks Quaternary and Pleistocene. San Pedro 1000 t Fresh-water sands, gravels and clays Pliocene Upper Pico 800 t Alternating sands and silt- Stones Pliocene Middle Pico 0-200 ± Sands and siltstones Unconformity Pliocene Repetto 875-1150 Gray and green shales, silt-stones and sands at top grading to interbedded gray-ish brown shales and fine-grained sands toward bot-tom Miocene Puente 4100± Hard brown shales and sands. Sands are fine and uncon-solidated at top, becoming firmer and coarser grained toward bottom. Top por-tion contains layers of lam-inated diatomaceous shale Unconformity Schist The data included herein are not complete as to all areas and zones, being confined mostly to the area south of Anaheim Street. The sections presented are illustrative of edge-water conditions in the Terminal zone and Tar zone, but have not been extended down the structure far enough

Jan 1, 1940

By Christopher W. Schram, Allan B. Tanner, Frank E. Senftle, George R. Boynton, Philip W. Philbin

A borehole sonde using a 252Cf neutron source and a Ge(Li) gamma-ray detector was field tested in a coal bed in Belmont County, Ohio, to ascertain whether such a device could be useful as a coal-exploration tool. As the sonde was lowered into the borehole, successive spectra were accumulated over short time intervals. The intensities of the capture gamma rays from hydrogen and of decay gamma rays from aluminum were determined simultaneously in each spectrum. A log of the intensities versus depth shows the depth and thickness of the coal bed. With the sonde stationary at points above, in, and below the coal bed, capture gamma rays were measured to show the variation in concentration of certain elements. From the spectrum recorded in the bed, a complete ultimate analysis, the percent ash content, and the heat content were determined without recourse to an external standard. Delayed gamma-ray analyses of the core were also made on the surface in the vicinity of the borehole in a fixed-geometry irradiation facility wing the detector in the borehole sonde. The concentrations of 10 elements were determined by this method on a coal split from the drill core. These experiments show that it is feasible to use a 252Cf- Ge(Li) borehole sonde as an aid in coal exploration.

Jan 1, 1979

By N. R. Green, N. J. Humphreys, D. McBride, T. N. Croft, M. Cross, D. M. Shevchenko

"Centrifugal casting offers a route to high quality products in difficult to cast high temperature low superheat alloys and thin section molds. Under centrifugal forces metal is forced into thin sections and can fill thicknesses of less than a millimeter. However, due to the high liquid metal velocities there is a high risk of surface turbulent flow and air entrainment within the liquid metal. The combination of interacting flow-thermal-solidification phenomena and associated defects is a challenging modeling task which the authors have previously described and validated. Capturing the metal-air interface, on what are inevitably complex three dimensional geometries, results in highly computationally expensive simulations and simulating a single cast can take weeks on a single processor. This contribution reports on modeling a complex centrifugal cast, gas entrainment, bubble transport and solidification, employing meshes of up to a million elements and investigates the scalability of the model on high performance clusters.Introduction The ultimate goal of any casting procedure is to produce a defect-free product. For difficult to cast alloys, such as Titanium, centrifugal casting has a number of advantage over conventional gravity methods [1]. In the casting of thin sections, such as turbine blades, the metal is forced into the thin sections under centrifugal forces. The centrifugal force can overcome the backpressure due to surface tension and the metal can fill mould sections with thicknesses substantially less than a millimeter. However, the materials used in these castings [2] tend to be highly reactive and requires low superheat. High liquid metal velocity gives rise to a high risk of free surface turbulent flow and of associated entrainment through free surface turbulence [3] and trapping of gas present in the flow [1]."

Jan 1, 2012

By John W. Chang

Introduction Automatic control of primary ball mill circuits has received much attention over the past decade, primarily because its advantages ultimately can be translated into economic terms. Apart from such obvious benefits as improved product quality, increased throughput, and more stable operation, less direct benefits such as easier operation, more orderly maintenance scheduling, and timely management reports all can be realized with the application of modern automatic process control equipment and techniques. Software configurable digital computer-based control systems offer ease of change in control strategies. Occasional control strategy changes are necessary whenever control objectives change or circuit modifications occur. The dependency of control strategies on control objectives and circuit equipment to effect optimal circuit operation is an important, but often neglected issue. Because of the potential for even better control, research and development work continues. [See (Ulsoy & Sastry, 1981) and (Hulbert & Braae, 1981).] Some of the possibilities are discussed later in this presentation. A few preliminary remarks may be in order concerning the relationships among control objectives, control strategies, and circuit equipment. Generally accepted control objectives for primary ball mill circuits include: 1. Maintaining a desired percent solids in the mill. 2. Maintaining a desired measure of particle size distribution at the cyclone overflow. 3. Maximizing throughput. Control Objective I is a requirement for proper operation of the ball mill, especially if it is a grate mill. It concerns smooth movement of material through the mill. Control Objective 2 is a product specification - one of the requirements for proper flotation operation. Control Objective 3, an expression of the desire to get the most out of the circuit, is the easiest to evaluate in economic terms. It assumes that the processes downstream

Jan 1, 1982

By E Ahern

In exchange for issuing minerals rights from the Crown Mineral Estate to explorers and miners, the Crown expects a æfair returnÆ on this investment, ultimately for the benefit of all New Zealanders. In the case of mining permits, this return is in the form of a tangible asset û royalties from mining activities. But for exploration activity, the return sought by the Crown is an intangible asset û information. The information obtained serves three purposes û in helping Crown Minerals to set work programme conditions during permit allocation, for monitoring the performance of permit holders in accordance with permit conditions, and for archiving and making available for future interested explorers and other parties. Difficulties can arise during the allocation and monitoring process when either party has more information than the other that is not shared. To date not enough emphasis has been placed on the intrinsic value and content of the information generated by explorers and the importance this information can have in the exploration process leading to new mineral discoveries. For attracting exploration investment, the quality and availability of such information, combined with other geoscientific data, is a fundamental determinant for potential explorers when choosing to explore in a global market, and strongly defines the mineral prospectivity for a country. This is something the Australian States and other jurisdictions seeking mineral investment learnt long ago, and who now provide substantial amounts of cheaply or freely available packaged geoscientific datasets, increasingly over the Internet. To have a vibrant mineral exploration industry so that the benefits from the mineral estate can be realised for all New Zealanders, a shift in emphasis to the value of its mineral information base itself is required. Such an approach is befitting of a true Knowledge Economy, and would enable the Crown to make better-informed decisions regarding utilisation of its natural resources.

Jan 1, 2002

By F Baars, M Zu, C A. RosiFre, L Lobato

A genetic model for the genesis of high-grade (>65 wt per cent Fe) Proterozoic, banded iron formation (BIF)-related iron deposits such as the Tom Price, Mount Whaleback deposits in the Hamersley Province (Australia), the N4E, N4W, N5 deposits at Carajßs (Brazil), the Aguas Claras, Conceitpo, and Casa de Pedra deposits in the Iron Quadrangle (Brazil), the Donkerpoort West, Kwagas East deposit in the Thabazimbi iron ore district (South Africa), or the Saksagan ore field at Krivoy Rog (Ukraine), needs to take into account the: timing of regional metamorphism with respect to the upgrade of BIF to high-grade iron ore; significance and relationship of the proto-ore to the hydrothermal alteration minerals and zonation and the process of iron enrichment; source and oxidation state of the hydrothermal fluids that caused the iron enrichment; types of geochemical processes that caused the hydrothermal alteration and iron enrichment; and significance of the widespread carbonatisation of the host rocks as a prerequisite for high-grade BIF-related iron mineralisation.We argue that a unifying model for high-grade BIF-related iron deposits cannot, presently, adequately explain the geological and geochemical characteristics observed in these deposits and, therefore, provide two end-member models that take into account the diversity of geological and geochemical ore deposit features. Our discrete model for the genesis of high-grade, BIF-related iron deposits is based on the interpreted tectonic setting, distinct hydrothermal fluid source of, and processes observed in, major BIF-related iron deposits. We divide two end-members: Proterozoic deep fault-magmatic (Carajßs) type, and Proterozoic rift-basin (Hamersley) type.Both end-members experienced varying degrees of deep weathering episodes that effected the hypogene enrichment and, ultimately, yielded the high-grade iron ore mined in many places today.

Jan 1, 2005

By C. V. Millikan

Production engineering has continued its rapid progress during the past year. Many engineering efficiencies long practiced in other industries are being rapidly accepted by the oil industry, and every branch of development and production work is undergoing study that is reducing the time and hazard in the drilling of wells even for greater depths, is securing better service from equipment, and is obtaining greater ultimate recovery from the reservoirs. Deviation of Drill Holes Deviation of drill holes probably has attracted greater and wider study than any other subject. Until about one year ago it had been given little attention. Some California operators knew the common magnitude of deviation, but Mid-Continent operators hesitated to believe that holes could be drilled so crooked. The great emphasis and publicity given to the seriousness of the problem resulted in the design of many instruments to record the deviation by chart or photograph. Instruments which would give the direction as well as deviation were not generally favored because of the grave fears of the legal complications which might result if the bottom of a producing well should prove to be on a neighboring lease. With all the instruments available for determining deviation, the use of etching on a glass bottle by hydrofluoric acid is still the most common method employed. The beneficial result of this earnest effort to drill straighter holes is proved by a comparison of deviation of wells completed recently with those completed over a year ago. The time of this change is arbitrarily taken as Jan. 1, 1929, as at that time the operators were aware of the deviation which usually occurred, and most of them were making some effort to reduce it. Table I shows averages of wells completed by several companies. Data on a few wells outside the greater Seminole area are

Jan 1, 1930

The process of mine planning at AnacondaÆs nickel and cobalt laterite operation located at Murrin-Murrin in the Northern Goldfields of Western Australia is carried out in a number of stages in an endeavour to determine the optimum mining sequence in order to maintain supply to the 4 Mtpa plant subject to operational constraints. The 296 Mt @ 0.99 per cent Ni and 0.064 per cent Co ore reserve (based on a cut-off grade of 0.8 per cent Nickel) is spread geographically widely over three regions comprising Murrin North (15 km + 15 km), Murrin South (7 km + 16 km) and Murrin East (5 km + 13 km) (refer Figure 2). The nickel mineralisation has been broken up further within each region into 18 separate manageable block models representing the 32 different deposits. The models are based initially on the 50 m + 50 m resource drilling for long term planning and updated with 12.5 m + 12.5 m grade control drilling prior to mining. Each of the individual block models are optimised using Whittle 4X software to provide the shells used as the basis for each of the 126 pit designs. The pits are generally nested with starter pits targeting the higher value shells with subsequent pits incrementally cutting back ultimately to the life of mine shells. A series of steps including: the coding of the individual pits into the block model; data export; TCL scripting (to calculate additional economic and tracking information); importing; and re-blocking; completes the transfer of the data into a MineMax (mixed integer linear programming schedule optimising software) model. Using MineMax and the application of operational and production constraints allows the optimisation, assessment and economic evaluation of alternative scenarios in order to determine the optimum life of mine plan and schedule.

Jan 1, 2003

By David A. Monaghan, Kenneth R. Maser, Adi R. Gurdar, D. Randolph Berry

1. Introduction This document represents Part II of our final report on the development of a "Remote Sealing System for Extinguishing Coal Mine Fires. " It is a technical report which summarizes the results of system development and field demonstration. Part I of this two - part final report is an Operator's Manual for the application of the Remote Sealing System to a coal mine fire. 1.1 Background When coal mine fires go out of control and can no longer be fought directly, the standard fire fighting technique is to construct air-tight seals in the mine passages leading to the fire area so'--,that the oxygen supply to the fire is". cut off. Ultimately, it is desirable to isolate the fire zone in such a way that normal operations can resume in the remainder of the mine. The construction of seals in the- mine causes the atmosphere to pass through a toxic and explosive phase. Explosions, if they occur, are not only hazardous to the men working at the sealing operation, but can also undo much of the sealing work which has already been accomplished. Sealing of passageways surrounding the fire zone from within the mine is extremely difficult and dangerous. Methods for direct sealing are detailed in "Control of Mine Fires'. 1 An alternative to this approach is the technique of remote sealing. This involves drilling boreholes which intersect the mine passages at the locations where the desired seals are to be constructed. The seals are then constructed by pouring material down the borehole and filling a segment of the passage from bottom to top. During this operation, there are no personnel in the mine, all operations taking place on the ground surface.

Jan 1, 1973

CONTENTS CATES, LOUIS S.-Factors Affecting Bank Slopes in Steam-shovel Operations. Discussed by Fred Hellman, Louis S. Cates, W. D. B. Motter, Jr., George S. Rice 1 CRANE, W. R.-Mine Subsidence in the Red Iron Ore Mines of the Birmingham District, Alabama. Discussed by George S. Rice, W. R. Crane, Louis S. Cates : 3 Factors Affecting Bank Slopes in Steam-shovel Operations Discussion of the paper of Louis S. CATES, presented at the New York Meeting, February, 1925, and issued, as Paper No. 1360-M, with MINING AND METAL-LURGY, August, 1924. FRED HELLMAN, New York.-My experience with shovel mining has been restricted almost entirely to Chuquicamata as far as operation is concerned. We had there an unusual condition in that the rock is cohesive because of the salts in it, so that you can probably work higher banks than is possible in most places. Recently they have reduced the height of the banks and have found that lower bank affords better working condition than the higher bank. It took two years of experimentation to determine the best height of bank for that particular mine. Each mine should be considered by itself and, to state off hand the best height of bank. for any given mine is impossible. We worked the high banks in Chile without much trouble. We adopted high banks in the beginning in order to obtain the minimum expense in railway approaches at that time. The first plan was for 50 ft.; then to get production started with the smallest possible expenditure of money, the approach to the deposit was changed and the first bank had an ultimate height of about 180 ft. We worked that bank; quite success-fully, but I do not think that it could be done anywhere else.

Jan 7, 1925

By W. K. Whiteford

Until the beginning of the year 1930, conditions in the oil industry were such that the production engineer was chiefly concerned with improving the efficiency of development and production technique. Good engineering practice had been adopted to devise and improve methods and materials better suited to drilling for and producing oil and gas. These efforts reduced the hazard and expense of deeper drilling, increased the ultimate recovery from reservoirs and lowered production costs. Equipment was of better design and materials were better suited for the work and were more permanent. These improvements naturally have contributed their share toward increasing the volume of crude oil produced each year. The industry is now faced with a need for preventing a waste of this natural resource; waste which came as a result of continued reckless drilling of new reservoirs. To make a careful study of this economic problem and to devise methods for correcting these conditions was a logical problem for the production engineer. Much time and study have been devoted to the question, and remedial plans have been suggested during the last year and a half. The principles of unit operation have attracted the engineer's attention, as they present ideal conditions for the most scientific and economical development of an oil field. Unitization During 1930 unitization of producing and potentially producing areas has made real progress, and as each new unitized development is agreed upon the objections that loomed so large at the inception of the idea fade into comparative insignificance. Undoubtedly the outstanding example of the efficacy of unitization is the Kettleman Hills project in California. Unitizing this structure, with its almost incredible reserve, is an important step forward in the industry's concerted effort toward conservation. With this partial acceptance of the principles of unit

Jan 1, 1931

A number of mines in Australia have experienced premature detonations caused by bulk explosives reacting with the rock type being blasted. Premature detonations are extremely high risk events as they are unplanned, occurring at any place, at any time, potentially resulting in high loss (personnel and equipment). Many Australian mines have also experienced spontaneous combustion where spilt explosive reacts vigorously with the rock type. Premature detonation in these cases does not occur due to the lack of confinement and the volume of explosive present, but these reactions could impinge on the surface initiation system and provide an early warning of future premature detonations. The explosive ground reactivity phenomena is not restricted to Australia with similar incidents being reported in North and South America, South Africa, China and South East Asia. All reported incidents have two common denominators, being the presence of sulphide rock types and nitrate based explosives. Both premature detonation and spontaneous combustion result from the same series of reactions of partially weathered sulphides that ultimately result in the violent decomposition of the ammonium nitrate based explosive. A number of relatively easily observable indicators can be used to assess a particular minesiteÆs potential for explosive ground reactivity. The presence of two or more of these indicators means that minesite personnel should contact their explosives manufacturer for assistance in determining if a problem exists and if so then developing strategies to overcome the situation. The paper describes the indicators as well as discussing, via a case study, the holistic approach required to efficiently develop a relevant æSafe and Efficient Blasting ProcedureÆ to deal with explosive ground reactivity problems.

Jan 1, 1999

By Murray D. Lester

The relationship between bauxite and energy has two distinct aspects. On the one hand, since virtually all of the bauxite that is mined winds up as aluminum metal, the economic health and future of the bauxite industry and of the bauxite-producing countries depend on the continuing vigour and competitiveness of aluminum against alternative metals and materials. The price of aluminum is, in turn, particularly dependent on the price of energy. Hence, the need for bauxite is ultimately affected by the price of energy. The second aspect relates to location of the bauxite industry. There is no shortage of bauxite resources in the world. For various reasons, as we shall see, there is a growing tendency toward the integration of bauxite mining, bauxite refining and aluminum smelting in those countries that have the resources both of bauxite and of energy necessary to support the entire production chain. Thus, the availability of attractive energy supplies will increasingly favour development of bauxite mining: the traditional export of bauxite as a simple raw material is likely to diminish in relative terms. In short, both the amount of bauxite mined and where this mining will take place are related to energy considerations. Let us first have a brief look at the four basic activities that are involved in our integrated operations: A. The bauxite is mined and moved to an ore plant. This step does not require more than relatively modest amounts of energy normally associated with excavation, loading and shipping of any bulk material. We need about four or five tonnes of bauxite for every tonne of metal produced.

Jan 1, 1984