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By Irving B. Cadoff, Stojan M. Zalar

AgInTe2, CuInTe2, and all Proportions of CuxAg1-xInTe, forMed homogeneous single phase alloys after direct solidification from the nielt. X-ray analysis indicated a zinc-blel~de strzccture typical of the chalcopyrite compounds, and the electrical resistivity and Sccbeck coefficient values were in the semiconducting range. AuInTe, and AuxA4g,-, InTe, formed by what appeared to be a peritectic reaction (the thermal analysis curves showing more than one arrest) and were conseyue~ztly polyphase. Substitution of copper into AgIrzTe, resulted in a continuous transition in the room tenzperature Seebeck coefficient from the negative AgIzTe, to the positive CuInTe,. A zero coefficient was obtained at about Cuo.55 Ago.45 InTe, . The temperatzire variation was similar to that observed for the stoichiometric compounds, that zs, tendency towards "p" concEuction at elevated temperatures. The thernzoelectric figure of merit for the compo~uzds, as determined by the Putley -Harmnn method were in the range 10- to 10-7 "K-l; the thermal conductivities in the order of 0.15 cal per sec-cm-oK. INCREASED interest in semiconducting intermetallic substances is expanding much of recent research from simple binary compounds into polyatomic systems and solid solutions. Ternary compounds A' represent a covalent extension of the binary semiconductors Within the a tin isoelec-tronic series, Ag-Cd-In-Sn-Sb-Te-I, divalent cadmium atoms in CdTe are being substituted for by monovalent silver and trivalent indium atoms to form the compound AgInTe, . By cross-substitution with elements of other isoelectronic series, a great number of ternary compounds A 'B"'c? is possible. In all of them, however, a necessary though not sufficient condition for the covalent, semiconducting bond—that there be four sharing orbital electrons per atom—must be fulfilled. In AgInTe,, each silver or indium atom is tetrahedrally surrounded by four tellurium atoms, while each tellurium atom is co-valently bound to two silver and two indium atoms. Synthetic chalcopyrites A'B"'c~ were first recognized as potential semiconduct&rs by Goodman and Douglas.' Austin, Goodman, and Pengelly discuss preparation difficulties and some electronic measurements on AgInS, , AgInSe, CuInSe, , AgInTe, , and CuInTe,. Chalcopyrites A B c2v are mentioned in papers attempting to classify and predict semiconducting behavior of intermetallic compounds; on the basis of saturated tetrahedral sp3 bonds,3 by specific selection criteria,' and by crystallographic considerations."

Jan 1, 1962

By K. Twite, K. Mujinga, J-M. Dereydt, P. Louis

"GECAMINES is a large mining concern and the world's leading cobalt producer having some of the richest cobalt deposits in the world. Cobalt is associated in the ore with copper as sulphides and oxides and in some locations with nickel too. Specific hydrometallurgical processes have been developed by GECAMINES which had done an important contribution to the development of the cobalt hydrometallurgy.In the Shituru plant, cobalt is obtained from an unique in-pulp electrolysis process, while in Lullu, cobalt is electrolyzed in a clear acidic solution giving a purer deposit. In the beginning of 1996 Shituru started the treatment of mixed Cu-Co-Ni Shinkolobwe hydrates obtained as by-product of an uranium solvent extraction plant. A typical analysis of this feedstock is: 2% Cu, 8% Co and 4% Ni.The nickel sulfide depolarized cementation process developed previously by GECAMINES was inefficient to treat such a high level of nickel contamination and it was decided to produce alloyed Cobalt-Nickel cathodes in the Shituru tankhouse.As anticipated from laboratory tests as previous studies and publications, a lower Ni/Co in the deposit was obtained compared to the Ni/Co ratio solution, despite the nickel reversible electrochemical potential is somewhat higher than the one of cobalt (-0.25 V vs -0.28 V).In this paper, the process flow-sheet and production data are given. Cobalt alloy with 5 - 20 % Ni was obtained at a production level of 300 t per month. The process developed is a new contribution to cobalt hydrometallurgy."

Jan 1, 1997

By A. T. Coumbe

The first survey 3/ covering sales of liquefied petroleum gases was made in 1930 by the Bureau of Mines, which at the time was under the United States Department of Commerce. This original canvass covered national totals for 1922 through 1929, and most of the supply came from natural gasoline plants. The 1930 report showed approximate totals for butane and propane and for butane-propane mixtures and pentane grouped together. No attempt was made to breakdown the national sales by various uses until 1931, when the quantities for domestic or household consumption, gas manufacturing, and industrial requirements, including miscellaneous uses were indicated. As the market for these liquid petroleum gases expanded and as new uses came into importance, their respective quantities were shown separately in the annual survey. Sales for internal-combustion engine fuel and for raw material for chemical plants were first taken out of the industrial total in 1936. During World War II liquefied petroleum gases became important as feed stock diverted to synthetic rubber plants, and consequently the survey was broadened to cover this particular demand, beginning in 1944. Pentane was dropped from the survey after 1943, as, being liquid at atmospheric pressure, it is not considered as one of the liquefied petroleum gases and furthermore, the quantity reported made up less than 1 percent of the total sales. Thirteen producing companies reported to the Bureau in the first survey made in 1930, and in the 1952 canvass about 130 producers--petroleum refiners and natural gasoline companies--and about 1,300 dealers cooperated by filing schedules showing a breakdown of their sales. Their 1952 deliveries of approximately 4.5 billion gallons of liquefied petroleum gases were equivalent to about 3.4 billion gallons of gasoline or 3.1 billion gallons of distillate fuel oil.

Jan 1, 1954

By H. R. Hendricks

The ore of the Iron King mine, being very hard and having a very fine crystalline structure, presents many problems in milling that are not present in ordinary lead-zinc ores. This very fine crystallization causes much interlocking of minerals and is most prevalent between the gold and pyrite and the sphalerite and pyrite. The recovery of gold is extremely important in the economic value of the ore and therefore constitutes a large part of the metallurgical problem to be solved. All of the gold is free but it has not been observed in any of the mill products except under very high magnification. Some of the gold is tarnished, and this condition also makes recovery difficult. The gold values have been determined to be highest in association with chalcopyrite and arsenopyrite. The silver occurs mostly in association with galena and tennantite. A small amount of native silver has also been observed occasionally. The galena, being softer than the other minerals, frees much better in grinding. Some oxidation of galena is present in the ore, as the non-sulphide lead content amounts to approximately 10 pct of the total lead. Some oxidation of sphalerite is also present in the ore. Microscopic examination of the zinc concentrate shows many grains in the minus 325-mesh to be half pyrite, together with the fact that some of the zinc is marmatite, makes production of a high-grade zinc concentrate very difficult unless recovery is sacrificed. In the grinding, it has been determined that the flotation feed must be maintained at 85 pet minus 200-mesh to free the minerals sufficiently to make the best economic recoveries. Table I illustrates the effect of fine grinding. It shows that the bulk of the recovered minerals is in the minus 325-mesh size and is the part of the minerals that is more readily freed. The pyrite concentrate is not given in the table because it contains practically no minus 325-mesh. Development of Present Flowsheet and Milling Practice The first milling operation started in 1938, with a mill capacity of 140 tons daily, producing a bulk gold-silver-lead concentrate. After several stages of expansion and changes of the mill flowsheet, the mill is currently treating 380 tons of ore daily and three separate concentrates are produced. In order of their importance and value, these are: (I) lead concentrate, (2) zinc concentrate and (3) pyrite concentrate. The present average grade of mill heads is: gold 0.11 oz, silver 4.00 oz, lead 2.50 pet, zinc 7.60 pct, copper 0.22 pct, iron 22 pct and 30 pct insolubles. Specific gravity of the ore is 3.8. During the period when bulk flotation mas practiced, the flowsheet was very simple. The ore was ground fine enough to liberate as much gold, silver and lead as possible. Necessary collectors and frothers were added in sufficient quantity

Jan 1, 1949

By H. R. Hendricks

THE ore of the Iron King Mine, being very hard and having a very fine crystalline structure, presents many problems in milling that are not present in ordinary lead-zinc ores. This very fine crystallization causes much interlocking of minerals and is most prevalent between the gold and pyrite and the sphalerite and pyrite. The recovery of gold is extremely important in the economic value of the ore and therefore constitutes a large part of the metallurgical problem to be solved. All of the gold is free but it has not been observed in any of the mill products except under very high magnification. Some of the gold is tarnished, and this condition also makes recovery difficult. The gold values have been determined to be highest in association with chalchopyrite and arsenopyrite. The silver occurs mostly in association with galena and tennantite. A small amount of native silver has also been observed occasionally. The galena, being softer than the other minerals, frees much better in grinding. Some oxidation of galena is present in the ore, as the nonsulphide lead content amounts to approximately 10 pct of the total lead. Some oxidation of sphalerite is also present in the ore. Microscopic examination of the zinc concentrate shows many grains in the minus 325-mesh to be half pyrite, together with the fact that some of the zinc is marmatite, makes production of a high-grade zinc concentrate very difficult unless recovery is sacrificed. In the grinding, it has been determined that the flotation feed must be maintained at 85 pct minus 200-mesh to free the minerals sufficiently to make the best economic recoveries. Table I illustrates the effect of fine grinding. It shows that the bulk of the recovered minerals is in the minus 325-mesh size and is the part of the minerals that is more readily freed. The pyrite concentrate is not given in the table because it contains practically no minus 325-mesh. DEVELOPMENT OF PRESENT FLOWSHEET AND MILLING PRACTICE The first milling operation started in 1938, with a mill capacity of 140 tons daily, producing a bulk gold-silver-lead concentrate. After several stages of expansion and changes of the mill flowsheet, the mill is currently treating 380 tons of ore daily and three separate concentrates are produced. In order of their importance and value, these are: (1) lead concentrate, (2) zinc concentrate and (3) pyrite concentrate. The present average grade of mill heads is: gold 0.11 oz, silver 4.00 oz, lead 2.50 pct, zinc 7.60 pct, copper 0.22 pct, iron 22 pet and 30 pct insolubles. Specific gravity of the ore is 3.8. During the period when bulk flotation was practiced, the flowsheet was very simple. The ore was ground fine enough to liberate as much gold, silver and lead as possible. Necessary collectors and frothers were added in sufficient quantity

Jan 1, 1947

Electric power curtailments resulting from the coal strike, required Noranda Aluminum, Inc. to shut down its 140,000 ton-per-year (tpy) primary aluminum smelter at New Madrid, Mo., and layoff 308 workers. Other primary aluminum production facilities affected by the coal strike included the Aluminum Company of America plant at Evansville, Ind. which shut down half of one potline; the Eastalco Aluminum Co., smelter at Frederick, Md., which cut production by 7 percent; and the National-Southwire Aluminum Co. plant at Hawesville, Ky. which cut production by 6 percent. Alumax, Inc. announced that construction had started on a 91,000 tpy potline at the Eastalco primary aluminum smelter. The new potline will be owned 65 percent by Alumax and 35 percent by Mitsui & Co. Ltd. Howmet Aluminum Corp., which currently owns 50 percent of the existing 176,000 tpy facility, has the option of becoming a 50 percent owner of the third potline in 1982. Construction of the new line was scheduled to be completed in 1980.

Jan 1, 1978

By S R. Green, G D. Corder

The legacy issues from mining can, and have often, extended well beyond the closure of operations. However, conventional cost-benefit analysis provides little incentive to implement initiatives at the project development stages of a new mining project as the costs that will be incurred towards the end of the mine life, 20 years or longer, appear minor in net present value (NPV) terms. This analysis can be misleading as the true costs of managing post-mining land can continue for many years, or decades, after mining ceases and any resulting unfavourable legacy issues can delay or prevent government permits or licences to develop new resources. Proper upfront planning is critical for implementing successful rehabilitation and closure strategies. The investment in this planning needs to be done in a structured and rigorous manner taking into consideration the long-term and broad benefits of sustainable land uses after mine closure. The advantages of such an approach could include the streamlining of regulatory approvals by early advice to the regulator of identified issues and responses to those issues, and clear evidence that a strong social licence to operate ethic with local, regional and national benefits is included in the decision-making process. This paper investigates the potential closure options for two case studies at the early stages of project development - concept and prefeasibility. By using a sustainability framework that can identify opportunities and risks, prospective initiatives that deliver enhanced environmental, community and social benefits will be compared with compliance-orientated approaches. This comparison is made across the Five Capitals Sustainability Model - natural, human, social, manufactured and financial. The results of this analysis demonstrate that upfront planning during project development and due care and effort during the life of the working mine will reduce the risks of long-term detrimental legacy issues. This will ultimately benefit the mine operator, the local community and the state.CITATION:Corder, G D and Green, S R, 2012. Using a sustainability assessment framework to achieve enhanced legacy outcomes, in Proceedings Life-of-Mine 2012 , pp 311-318 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By W. W. Odell

ONCE it was believed that anthracite or coke were the only fuels generally available and suitable for the generation of water gas, particularly so when this gas was made in the generators of standard carburetted water-gas sets such as are commonly used in the manufacture of city gas. During the past 8 years, practice has changed considerably and it is -now common to find gas plants operating without anthracite or coke and using bituminous coal in the generator. This change in fuel has appreciably increased the marketability and sales of certain coal producers' products; accordingly it is of interest to coal operators and others to know the reason for this change, the present trend in practice and the adaptability of various coals for generation of water gas. This paper briefly discusses these conditions and some of the factors relating thereto. BITUMINOUS COAL NOT IDEAL BUT CHEAPER THAN COKE In spite of many changes which have been made in both process and generating apparatus for using bituminous coal as generator fuel more efficiently, in general it is not an ideal fuel for this purpose. It is supplanting coke because it costs less; it is so much cheaper per ton delivered at the gas works that water gas made therefrom costs less per unit-volume than that made from coke, even though the quantity of generator fuel consumed per therm (100,000 B. t. u.) of gas made is greater with coal. This is the reason why so many city gas plants, as well as others, are using bituminous coal instead of coke.

Jan 1, 1927

By Syd S. Peng

Is the laboratory sized coal specimen much stronger than underground coal pillars? The answer to this question has a profound implication to many coal operators. It will decide how much of the coal reserve can be recovered. Or, in many cases, it will determine whether it can be mined economically. Recent trends in several eastern states to establish regulations regarding coal pillar design to prevent surface subsidence long after mining heighten the debates. And, in some cases, these trends highlight the existing practices that seriously question the conventional wisdom. Currently, nearly all researchers and practitioners agree that as the size of rock specimens increases, its strength decreases. This concept has been universally adopted as the basic principle for coal pillar design in the United States. Several formulas have been derived to account for this effect. The reduction factor for underground coal pillars ranges from one-half to one-sixth of the strength obtained in the laboratory, depending on the formula selected. Recent case studies indicate that the reduction factor is not justifiable, at east in some cases. The use of a reduction factor is based on the assumption hat smaller rock specimens as tested in he laboratory contain none or fewer fractures or planes of weakness than larger specimens or underground coal pillars. In other words, the larger the rock materials, the more fractures it contains and subsequently weaker in strength. Do all underground coal pillars have more fractures than laboratory sized coal specimens? Not necessarily. All coal contains cleats. Some are con¬spicuous but others are not. In terms of cleat density (number of cleats per unit area), there is no difference between an underground coal pillar and a laboratory sized specimen, provided the specimen size is larger than the cleat spacing, which is mostly 25 to 75 mm (1 to 3 in.).

Jan 1, 1993

By Felipe Calizaya, Sekhar Bhattacharyya

Mechanized underground mines suffer from noise overexposure. Noise levels are often above the Permissible Exposure Limit (PEL) where underground fans are used. Sound levels in active workings can reach up to 121 A-weighted decibels (dB(A)), especially when fans are not equipped with silencers. Use of silencers seldom ensures PEL. Overexposure of noise induces permanent hearing loss among mine workers. A NIOSH-funded research project and field studies at six coal and non-coal mines revalidated the findings. The University of Utah undertook laboratory studies to reduce fan noise at the source. A new silencer prototype with varying noise dampening material was designed and tested. The silencer and associated extension can be repacked with different dampening materials. The silencer and the extension were used in various configurations. Attempts were also made to simulate field conditions. The tests demonstrated a maximum sound level attenuation of about 14 dB(A) at the fan discharge. A properly designed silencer offers lesser resistance and thereby better fan performance and lower energy cost. The re-packable silencer is more likely to be maintained properly. Lowering of noise level happens in audible frequencies (4000 to 8000 Hz) which are important in A-weighting.

By R. W. Watson

A belt-wearable self-contained self-rescuer (SCSR) manufactured by the CSE Corp. and designated the "SR-1OO" was evaluated for safety in the underground mine environment by the U.S. Bureau of Mines. The evaluation consisted of laboratory tests on the chemicals contained in the unit and field trials to simulate the mine environment. This report summarizes the test results and compares the results with those from earlier tests with chemical and compressed oxygen self-rescuers. It was concluded that the new SCSR did not pose any different or more severe hazards than the earlier units. In view of the mine-proven safety record of the SCSR's now in service, no reason could be found to disallow use of the belt-wearable unit.

Jan 1, 1991

By J. R. Ruark

This report presents results of mining operations and of research and development work done during stage I of the gas combustion retorting research program conducted by the Colorado School of Mines Research Foundation and six major oil companies at the Bureau of Mines Anvil Points Oil Shale Facilities. A brief description of the gas combustion process is given and the experimental program is discussed. Included in this discussion are (1) air-gas distributor development, (2) results of gas and shale distribution studies, and (3) effects of other process variable studies. The report concludes with a statistical evaluation of experimental results. Two appendixes present a chronological account of the experimental work and tabulations of data for all retorting runs conducted during stage I.

Jan 1, 1969

By E. W. Edson, F. W. Hertal

In some fields the problem of mud fluid is simple and easy of solution. But in the Ventura Avenue field the acquisition and disposal of good drilling mud is not the least of the problems that confront the operator. In fact, mud fluid in the Ventura Avenue field is a very important factor in the drilling of the wells. It is quite probable that many of the factors affecting mud in this field will not be found in most of the fields with which the reader is familiar. However, in the fields where the mud fluid causes no apparent problem it is probable that some of the points brought out in this paper could be used to economic advantage. In fields where caving and squeezing formations and high gas pressures are present, as in the Ventura Avenue field, it is believed that application of methods outlined will be of great assistance in drilling wells. On account of the sandy nature of the formation and the lack of suitable shale bodies in the strata drilled through in the Ventura Avenue field, the wells make practically no mud during drilling. It is necessary therefore to supply drilling mud to the wells that will carry the drill cuttings to the surface, and also will " wall up" the drill hole and prevent the sandy formations from caving. Mixing and Handling Mud Fluid The clay used to make the mud fluid is obtained from a shale stratum in the upper Pico (Plioccne) formation found about a mile on either side of the field. Since high gas pressures and caving formations were first encountered in the Ventura Avenue field and mud fluid was needed to combat them, the mixing of this mud fluid has gone through a process of evolution. First, the clay was mined and hauled to the derrick, where it was shoveled into the well and left for the churning action of the bit to mix into a mud in the hole. The next move was the construction of a mixer to mix the clay to a mud fluid which was pumped into the well. These mixing

Jan 1, 1930

By H. Hamza

Oil sand tailings are disposed of in large ponds in which MFT (Mature Fine Tailings, a stable suspension of fine particles in water) forms after many years of settling. Long-term storage of large volumes of MFT is costly to maintain and also poses an environmental liability. The Advanced Separation Technologies laboratory at CANMET Western Research Centre has worked closely with oil sand companies to eliminate MFT generation by applying paste technology to oil sand tailings. In this process the fine tailings are flocculated to produce a thickened material that has the potential to consolidate to a dry landscape, while warm water is recovered and recycled for reuse in the extraction process. This paper presents some results of an extensive technical program involving bench-scale tests for flocculant selection and continuous thickener pilot tests.

Jan 1, 2002

By M. Yavuz, M. Aksoy, G. Once, M. Iphar

This paper is concerned with a study on the floor heaving in the transport road of the GLI Omerler Colliery in Tuncbilek-Turkey. This gallery has been opened at the depth of 200 m through the formation of marl in 4.6 m width and 3.5 m height in cross section. Floor heaving occurred up to 70 cm in height in maximum and caused severe problems in railway and band-conveyor transportation in the main road. In addition; after the current panel mined out, the shield support units could not be transferred to the new panel because of the deformation of roadway cross-section. The I-profile steel arch supports also sank into the weak floor rock. This situation has been studied by numerical analysis using the FLAC3Dfinite difference program in order to investigate the rock mass behaviour around the opening. The obtained outputs of the numerical model have showed consistency with the amount of floor heaving in the gallery at 200 m depth. A new gallery has been driven at the depth of 115 m and M4 longwall panel has just been taken to production. So as not to encounter with the same problems at 200 m depth, especially longwall face moving problem, various numerical models have been studied in order to keep the floor heaving in the acceptable limits required to move shield support units. Keywords: Floor heave, Numerical modelling, FLAC3D, Failure criteria, RocLab

Jan 1, 2003

By S. Floreen

Measurements have been mode of the effects of tempering and austenitizing heat treatments, the work-hardening characteristics, and the effects of test temperature and strain rate on the properties of a low-carbon Fe-18 pet Ni martensitic alloy. In many respects the alloy behaved quite similarly to cold-worked iron. One notable quality was the excellent ductility at temperatures as low as 20°K. Many of the qualities of the maraging steels could he related to the properties of the Fe-Ni matrix. THE 18 pet Ni maraging steels have demonstrated that unusual combinations of strength and toughness may be obtained by age hardening a low-carbon Fe-Ni martensite matrix.' These properties must, to some extent, reflect the properties of this Fe-Ni matrix, and therefore an understanding of the properties of this matrix is a prerequisite to a complete understanding of the steels. There have been several recent studies of Fe-Ni-C martensites, but not much attention has been paid to alloys with very low carbon contents. At low carbon levels the crystal structure of these alloys is essentially bee.2 Electron transmission microscopic examination of a 20 pet Ni binary alloy showed martensite platelets separated by low angle boundaries.3 Plastic deformation of the low-carbon alloys has been shown to proceed by wavy glide.4 The hardness of these martensites is typically RC 28, and their yield strengths are 70 to 80 kg per sq mm.2, 5 Their ductility is excellent. Room-temperature tensile elongations of 18 pet and reductions of area of 70 pet have been observed in an Fe-18 pet Ni binary alloy.5 These observations have provided a qualitative understanding of the flow characteristics of these alloys. To date, however, no thorough study of their properties has been made. In particular, it is not known to what extent the deformation characteristics of low-carbon martensites are similar or dissimilar to those of pure iron or other bee metals. The present work was undertaken to provide more detailed information on the flow characteristics of a low-carbon Fe-18 pet Ni martensite. PROCEDURES, RESULTS, AND DISCUSSION Materials. A 40-lb heat of the Fe-18 pet Ni alloy used in this study was made by vacuum-induction melting. The charge materials were electrolytic iron and electrolytic nickel. A carbon boil was used to achieve deoxidation. After the boil the heat was refined by additions of 0.1 wt pet Ti and Al. These additions are commonly used in the maraging steels to keep the carbon and nitrogen contents in solid solution at a minimum. After casting, the heat was

Jan 1, 1964

By Joseph W. Horne

This report presents the results of an investigation by the U. S. Bureau of Mines in cooperation with the State of Colorado, on the yields and properties of oils produced from oil shale, lignite and subbituminous coal using the standard assay method developed by the Bureau for oil-shale testing,. The purpose of this work, which is part of the general study of oil shales being conducted by the Bureau of Mines and cooperating agencies, was to obtain information on the amount and character of the yield of crude oil or tar from different typical oil shales, the yield of light oil or naptha that might be suitable for use in motor fuels, and other products of shale oil. As the west has large resources both of oil shale and low-grade non-coking coals, it is of interest to know the relative yields of tars, light oils, and combustible gases that can be produced from these coals when retorted under conditions similar to those suited for oil-shale retorting. Source of Samples The coal samples were obtained from deposits on or adjacent to the public lands in the States of the Rocky Mountain region. Many of the mines sampled are operating under Government leases or permits. The number of coal samples secured from the various states are: Colorado, 6; Montana, 9; north Dakota, 6; New Mexico. 1; South Dakota, 1; Wyoming, 9. Of these samples, 14 were lignite coal, 16 subbituminous coal, and a bituminous coal. The standard channel method of the Bureau of Mines was used for sampling. Coal samples received at the Boulder Office weighed about twelve pounds each, and duplicate samples were sent to the Pittsburgh Station for proximate and ultimate analyses. The origin of the samples and description of the deposits are given in Table 1.

Jan 1, 1927

By L. J. Terrill

Lateral displacement in the immediate roof beam at the Waste Isolation Pilot Plant (WIPP) is a significant factor in assessment of excavation performance for the design of ground control systems. Information on roof beam lateral displacement, expansion, fracture formation, as well as excavation convergence, is gathered using a variety of manually and remotely read instruments. Visual observations are also used when possible. This paper describes the methods used to measure lateral displacement, or offset, at the WIPP. Offset magnitudes are determined by the degree of occlusion in drillholes that intersect the offset plane. The Borehole Lateral Displacement Sensor (BLDS) was developed for installation at WIPP to monitor offset at a high degree of accuracy at a short reading frequency. Offset measurements have historically been obtained by visual estimation of borehole occlusion. Use of the BLDS will enable relationships between time dependent roof beam lateral displacement and expansion to be established in much shorter periods than is possible using visual observations. The instrument will also allow remote monitoring of roof beam displacement in areas where visual estimations are not possible. Continued monitoring of roof beam displacement, convergence, and expansion, is integral to timely and pertinent assessments of WIPP excavation performance.

Jan 1, 1996

By Joseph E. Pouge

For the purposes of this analysis it is assumed that the petroleum industry has undergone a basic economic change whereby the degree of competition present in its operation is reduced by the collective control of production brought about by statme-directed proration. Formerly freely competitive in all its parts, the industry is now fully competitive only in its marketing, its manufacturing and transportation, its search for new oil supplies, its drilling operations (with some qualifications), and its capital movements. The practical problem before the industry in its new status is the maintenance of equilibrium, with planned control of crude-oil production (proration) substituted for competition and price as the regulatory mechanism at one point in the supply-demand system. It is further assumed that proration has become so firmly established in the legal and operating framework of the business that it may be looked upon as an institution. The purpose of this paper is to call attention to the effect of unregulated drilling upon the orderly functioning of proration. Economic Structure of Petroleum Industry The economic structure of the petroleum industry, under the current form of proration, may be visualized, in simplified form, as shown in Fig. 1. This diagram is designed to indicate the existing mechanism whereby supply and demand are equated. Demand is created largely by conditions external to the oil business, whereas supply is conditioned by a series of stages incidental to the discovery, development and production of a resource. The time elements involved in changes in demand and supply are of an entirely different order, the demand factor being much more flexible and "quicker" than the supply factors. It should be observed, also, that the position of price, formerly between "demand" and "supply," has been moved to a sidewise location where it still affects demand but influences current supply only through its bearing upon proration, drilling and search. Proration has been substituted for price as a throttle at the well head, but at this point only. The mechanism now works in this fashion: a declining price stimulates demand and the

Jan 1, 1936

By Joseph E. Pouge

For the purposes of this analysis it is assumed that the petroleum industry has undergone a basic economic change whereby the degree of competition present in its operation is reduced by the collective control of production brought about by statme-directed proration. Formerly freely competitive in all its parts, the industry is now fully competitive only in its marketing, its manufacturing and transportation, its search for new oil supplies, its drilling operations (with some qualifications), and its capital movements. The practical problem before the industry in its new status is the maintenance of equilibrium, with planned control of crude-oil production (proration) substituted for competition and price as the regulatory mechanism at one point in the supply-demand system. It is further assumed that proration has become so firmly established in the legal and operating framework of the business that it may be looked upon as an institution. The purpose of this paper is to call attention to the effect of unregulated drilling upon the orderly functioning of proration. Economic Structure of Petroleum Industry The economic structure of the petroleum industry, under the current form of proration, may be visualized, in simplified form, as shown in Fig. 1. This diagram is designed to indicate the existing mechanism whereby supply and demand are equated. Demand is created largely by conditions external to the oil business, whereas supply is conditioned by a series of stages incidental to the discovery, development and production of a resource. The time elements involved in changes in demand and supply are of an entirely different order, the demand factor being much more flexible and "quicker" than the supply factors. It should be observed, also, that the position of price, formerly between "demand" and "supply," has been moved to a sidewise location where it still affects demand but influences current supply only through its bearing upon proration, drilling and search. Proration has been substituted for price as a throttle at the well head, but at this point only. The mechanism now works in this fashion: a declining price stimulates demand and the

Jan 1, 1936