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By Todd M. Ruff

The majority of fatalities that occur in road construction work zones in the United States involve a worker being struck by a piece of construction equipment or other vehicle. The Spokane Research Laboratory of the National Institute for Occupational Safety and Health, in cooperation with the Washington State Department of Transportation, is evaluating methods to decrease these accidents. One such method uses devices that assist equipment operators in monitoring blind areas around the equipment to prevent collisions with workers on foot or other objects. Several cameras and sensor systems are available for this application, and a study was conducted to evaluate these systems on various trucks used in road construction and maintenance. Tests were conducted using sanding trucks during the winter months, which allowed researchers to investigate the effectiveness and limitations of various technologies under the most extreme conditions. Tests were also conducted using dump trucks during the warmer months to study the effectiveness of the systems in highway work zones. Results show that many difficulties arise when using camera and sensor systems in cold, snowy climates. And, while the operation of these systems is more reliable during the warmer months, challenges still exist in using them on equipment in crowded work areas.

Jan 1, 2004

By I. E. Rosenzweig

GEOPHYSICAL prospecting by earth-resistivity methods is frequently applied to investigation of structural problems in geology. Fig. 1 indicates a scheme of the general arrangement used in these methods of measurements. The battery (or generator) E is connected with two "current electrodes" II and 12. The current of intensity J, supplied by this battery, passes through the earth between these elec- FIG. 1.-GENERAL ARRANGEMENT OF APPARATUS. trodes. A potential difference U will be measured between two other electrodes V1 and V2, called "potential electrodes." According to the configuration of electrodes (Fig. 1), the resistivity of a homogeneous soil results from the formula p = 2pcaU/J [1] where c=1/a/b11 - a/b12 ? (a/b21-a/b22) [2]

Jan 1, 1938

By Fred N. Kissell

This handbook describes effective methods for the control of methane gas in mines and tunnels. It assumes the reader is familiar with mining. The first chapter covers facts about methane important to mine safety, such as the explosibility of gas mixtures. The second chapter covers methane sampling, which is crucial because many methane explosions have been attributed to sampling deficiencies. Subsequent chapters describe methane control methods for different kinds of mines and mining equipment, primarily for U.S. coal mines. These coal mine chapters include continuous miners and longwalls, including bleeders. Coal seam degasification is covered extensively. Other coal mine chapters deal with methane emission forecasting and predicting the excess gas from troublesome geologic features like faults. Additional coal chapters contain methane controls for shaft sinking and shaft filling, for surface highwall mines, and for coal storage silos. Major coal mine explosion disasters have always involved the combustion of coal dust, originally triggered by methane. Thus, a chapter is included on making coal dust inert so it cannot explode. Methane is surprisingly common in metal and nonmetal mines around the world, as well as in many tunnels as they are excavated. Accordingly, a chapter is included on metal and nonmetal mines and another on tunnels. Proper ventilation plays the major role in keeping mines free of hazardous methane accumulations. The ventilation discussed in this handbook, except for the chapter on bleeder systems, deals only with so-called face ventilation, i.e., ventilation of the immediate working face area, not ventilation of the mine as a whole. The omission of whole-mine ventilation was necessary to keep this handbook to a reasonable size and because a huge amount of excellent information is available on the subject.2

Jan 1, 2006

By B. H. Caudle, A. B. Dyes

In a recent publication' it was shown that wells with a free surface in a homogeneous gravity-drainage reservoir have a hyperbolic decline with index n '. This paper reports efforts to extend this theory to practical field cases. As a first step in making the extension, a large number of lease production curves from gravity-drainage fields in the stripper stage were fitted with the general hyperbolic decline equation, q/q, = 1/(1 + y) y and n in each case being determined by statistical methods. It was found that this equation is reliable for decline curve extrapolation for periods up to at least 25 years. The resrilts obtained were disturbing in the sense that values for the index, n, were often smaller than one, which fact leads to the prediction that a well would produce all infinite amount of oil in infinite time. A theoretical investigation based on the results of the previous paper provides a suitable explanation for these low values of n. It suggests that these are obtained if production occurs from two or more layers of diflerent permeabilitv and thicktress or two lnyers having different skin effects. It is predicted that as the more permeable layers are exhausted, the index of decline, n, will rise from a value smaller than 2, to n = 2. A practical method is given for fitting the general hyperbolic decline Eq. 6 to production decline data. When this method is used, the index of decline observed in gravity-drainage reservoirs in the stripper stage when wing only data over early years 01 decline usually agrees quite closely with that determined using data over 25 years or more. This indicates that the hyperbolic decline equation is reliable for predicting behavior of such reservoirs. A method is also suggested for taking into account any changes in the value of the index INTRODUCTION As a result of both experimental work with models and theoretical deductions, it was recently concluded' that wells having a free surface in a homogeneous reservoir producing by pure gravity drainage should have a hyperbolic decline with n = 2. The present report details efforts to extend this work on ideal homogeneous reservoirs to actual field cases. It should be remembered that both the previous work and the present extension are based on the assumption that the reservoir is at very low pressure, and hence, nearly all the potential available for driving fluid to the well is the gravity head. Attempts to apply conclusions of this study to reservoirs which have considerable pressures supplementing the gravity drive may lead to difficulty. WELLS WITH NO FREE SURFACE In a dipping gravity-drainage reservoir such as that shown in Fig. 1, some of the down-dip wells have no free surface. The previous study' showed that the up-dip wells, which have a free surface, should follow Eq. 1. The following approximate analysis, of a type which was justified experimentally for up-dip wells in the work just mentioned, leads to results for the down-dip wells.

By M. A. S. Siraa

A program of work was undertaken at the Kennecott Smelter and Refinery to model the complex. This effort contributed a total of eight models of the plant: flash smelting furnace, flash converting furnace, slag concentrator, anode furnace, offgas scrubbing system, acid plant, hydrometallurgical dust treatment plant, and the precious metals plant. Some of these models have been used in a variety of investigations ranging from offgas capacities for a steam generation analysis to an examination of impurities. The culmination of this enterprise has resulted in an on-line control scheme for the flash smelting and flash converting furnaces. These two process control schemes incorporate their respective steady-state heat and mass balances that are executed in response to feed changes while a feedback loop calculates when product grade and temperatures deviate from setpoints. This system has been put into place to improve furnace control and on- line time.

Jan 1, 1999

By Melvin W. Kraschnewski

In 1966 Central Ohio Coal Company and Bucyrus-Erie signed a contract authorizing Bucyrus-Erie Company to design and build a 220 cubic yard dragline. This dragline would be used for stripping overburden from their coal reserves located near Cumberland, Ohio. The size of the machine was arrived at after a thorough application study of their annual coal output requirement, depth of overburden and type of terrain. The design and construction of this machine which has been designated by BECO as model number 4250-W is the title of this paper. Size wise based on machine weight the 4250-W represents an increase factor of three over our largest current dragline. Probably the easiest way of presenting a machine of this size is to build it from the bottom up.

Jan 1, 1969

By C. A. Bruch, J. F. Duffey

On the basis of metallographic and cooling-rate studies of 15 U-Zr alloys, a new version of the 6 phase region of the U-Zr phase diagram is proposed. IN several published diagrams of U-Zr alloy system:' there is good agreement that at elevated temperatures complete solid solubility exists between y uranium and ß zirconium. Similarly, there is reasonably good agreement concerning the uranium-rich and zirconium-rich ends of the diagram. However, there is no agreement concerning the nature of the diagram at intermediate compositions and at temperatures below about 650°C. The early work of Saller et al.8 hows an intermediate phase, 6. In a later diagram by Saller and Rough' shown in Fig. 1, the d phase field is drawn with dotted lines, indicating doubt that this phase exists. The diagram of Summers-Smith2 does not show the d phase. More recently Holden and Seymour' have shown that in the composition range 40 to 60 wt pet Zr, the high-temperature ? phase, which is body-cen-tered-cubic, transforms to an ordered structure, 8. They found that the order-disorder transformation occurs between 595° and 610°C, and presented a diagram based on the study of four different alloy compositions. Most recently Saller et a1.5 presented a new diagram which differs with respect to the composition limits of the 8 field from the others proposed by these authors. The purpose of the present investigation was to determine the boundaries of the d phase field. Experimental Procedures and Results Alloys—Buttons, weighing 80 g of 15 different alloy compositions were prepared by arc melting Mal-linckrodt uranium and iodide-process zirconium in a water-cooled crucible. A controlled atmosphere of argon and helium was maintained in the furnace. Prior to making each button, a sacrificial button of zirconium was melted to increase the purity of the furnace atmosphere. Each alloy was then melted six times to improve its homogeneity. Subsequently the alloy buttons were jacketed in copper and hot rolled to slabs at 775°C. From these slabs, specimens were machined for chemical, thermal, and metallographic analyses, Table I gives both the estimated chemical composition of the alloys, and the values which were obtained by analysis. The oxygen contents varied from 0.013 to 0.032 pet, nitrogen from 0.0014 to 0.014 pet, and carbon from 0.0013 to 0.011 pet. The purity of the alloys ranged from 99.947 to 99.975 pet. Thermal Analysis—The specimens for thermal analysis were blocks 11/4 x 1/4 x % in. The bead of a calibrated thermocouple was placed between two of these blocks and molybdenum wire was wrapped around the assembly. Each assembly was sealed in a quartz capsule having an argon atmosphere. The capsule was placed inside a refractory crucible which was heated in a furnace. Using a method described by Smith,' the emf of a differential thermocouple, with junctions inside and outside of the refractory crucible, was used to activate the

Jan 1, 1959

By E. J. Fasiska, L. Zwell

PREVIOUS investigations 1,2 of Fe3P described by pearson3 and schubert4 show that Fe3P has a bct unit cell having four Fe3P tetrahedra centered around each lattice point. The space group is 14, No. 82, and all atoms occupy general positions 8(g). The cell dimensions3 are: a = 9.090, c = 4.446 kX, with an axial ratio of c/o = 0.4891. We have measured the lattice parameters of Fe3P, using a Fe as an internal temperature standard, at 23°, 414°, and 678°C and computed the thermal expansion over this temperature range. The Fe,P was prepared by melting under vacuum (after flushing with argon) a commercially pure iron and "ferrophosphor" in a high-frequency induction furnace. Part of the ingot was crushed for X-ray examination and for chemical analysis. X-ray diffraction and light microscopy indicated iron phosphide (Fe3P) present as the major constituent and a small amount (about 5 pct) of a Fe. Chemical analysis showed 0.05 wt pct Si, 0.008 wt pct N, 0.018 wt pet C, and less than 0.02 wt pct each of other metallic elements. X-ray diffraction powder patterns were obtained from a mixture of iron and Fe3P sealed in an evacuated quartz capsule using a Unicam high-temperature

Jan 1, 1968

By Roy McKinstry, Mark Rantapaa, Thomas Bolles

"More efficient drilling and blasting techniques have shown measurable improvements in throughput at the Barrick Goldstrike wet grinding mill.A decrease in throughput at the autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the Open Pit and Process areas participated closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of improving throughput in future years, despite the projected harder ores. Plant studies were conducted to determine if adjustments to drilling and blasting could positively influence throughput. At the Goldstrike mill the greatest opportunity from the D2M initiative is realized on the hardest ore. Grinding throughput for softer ore, <15 kWh/st, can meet or exceed the downstream pressure oxidation requirements. Grinding throughput for harder ore, >15 kWh/st, is limited by the SAG milling capacity. Better fragmentation in the D2M ore, as demonstrated by image analysis, increased throughput 5% to 10% (25 to 50 stph) compared to the standard mining methods.Better fragmentation and a subsequent increase in mill throughput were achieved through the use of:1) Electronic caps for more precision and flexibility, as well as for allowing extremely fast shots.2) Explosives with a higher velocity of detonation (VOD), to provide for improved shock energy.3) Improved distribution of the explosives by decreasing pattern spacing.INTRODUCTIONThe Barrick Goldstrike Open-Pit group, along with the Process division, began experimenting with novel blasting technology and techniques to improve mill throughput in the spring of 2001. A series of tests were developed to determine if fragmentation and ultimately mill throughput could be influenced by optimizing the drilling and blasting program in known"

Jan 1, 2004

I HAVE hitherto shown you as well as I knew how the procedure for those operations which are needed in melting on either a large or small scale, as you might need them. Now I wish to pass on to some other operations which, while related to the operations and power of fires and also to certain kinds of melting, are not wholly connected with the art of casting. First I wish to begin with the actual substance of the art of alchemy, which is sought and desired with so much zeal. Then, as a useful and ingenious thing, I wish to inform you of the art of distilling, and, afterwards, how you should operate a mint in an orderly fashion and without burden on the conscience. Then I shall tell you of the ironworker, the goldsmith, the coppersmith, and some others, as you will be able to see in their places.

Jan 1, 1942

By Edwin R. Phelps

In the year 1900 about 212 million tons of bituminous coal were produced in the United States. Almost none of this was produced by surface mines (Fig. 1), because there was no large equipment suitable for stripping overburden at that time. By 1915 the surface mines had built up their capability largely through use of the steam shovel to the point that they produced 2.8 million tons of the nation&apos;s total production of 443 million tons. Over the intervening years between 1915 and 1970 surface mining provided a continually increasing percentage of the nation&apos;s bituminous coal, stimulated by the growing availability of giant surface mining machines, some of which are presently capable of removing 220 cu yd of earth with one bite of their mighty buckets. In 1970 the nation&apos;s surface mines produced 244 million tons of bituminous coal, over 40% of the total national production. On the other hand, the nation&apos;s underground mines hit a peak of 560 million tons in 1920, dropped to a low of 273 million tons in 1961, and are presently on a very slow rise. Environmental pressures generally oppose surface mining, and have forced coal companies to consider more underground mining in future planning. Also, since strippable reserves are decreasing in the eastern states, an increase in underground mining is expected over the coming years. However, in the western states there are enormous reserves to be extracted by surface methods. Why has surface mining increased, while underground mining has decreased? It&apos;s largely a matter of economics. The cost per ton is greatly reduced by surface mining because of the relative ease of obtaining the coal. Also, there is a much greater percentage of coal recovery-nearly 85% in surface mines within the minable area, as compared to an average of about 50% in underground mines. Much surface mining recovers coal that could not be extracted by underground methods because of coal bed thinness, or multiple beds close together, split seams, the nature of the roof, and other geologic conditions. What are some of the limitations of surface mining? First of all, with presently available machinery it is difficult to surface mine at depths

Jan 1, 1973

By Lawrence D. Hoy, Armand Savoie, Pierre Trudel, Ghislaln Tourigny, Robert Crépeau, Lao Kheang

"Recent fluid inclusion and stable isotopic studies in the Bousquet mining district have identified spatial and temporal trends in mineralization temperatures and isotopic compositions of vein forming fluids. These studies indicate that mineralizing temperatures were lower during sterile vein formation (T=200-300°C) than during auriferous vein formation (T = 300-400°C), and that 8 80 values of minerals in sterile veins are lower by 1-3 %o than in associated auriferous veins. In addition to these small differences in 8 80 within individual mineralized zones, a trend of increasing 8 80 values of vein minerals is identified from west to east across the district, with 8 80 of vein minerals increasing by4-6%o. Quantitative evaluation of potential causes of the observed oxygen isotopic shifts suggests that the best explanation for these trends is the derivation of the mineralizing fluids from an isotopically inhomogeneous terrain in which the fluid isotopic compositions are controlled by the isotopic compositions of the host lithologies due to high rock/water ratios in these source terrains. This inhomogeneous source terrain is interpreted as consisting of the Blake River Group volcanics (low 8 80 component) and the adjoining Kewagama and Cadillac Group sediments (high 8 80 component).The genesis of the hydrothermal fluids is attributed to crustal heating during metamorphism, with the fluids representing metamorphic dewatering products and/or fluids incorporated during deposition and burial of the host lithologies. Ductile deformation of the fluid source regions impeded fluid migration during metamorphism; the ultimate release of the mineralizing fluids is attributed to the penetration to depth of vertical structures (fault and shear zones) during brittle deformation of the crust under waning metamorphic conditions. Release of fluids caused by this puncturing of the closed hydrologic source regime produced a localized zone of lowered pressure, drawing fluids from adjacent lithologies toward the fault zones, feeding further hydrothermal fluid upwelling. Au mineralization resulted from chemical processes related to cooling of the hydrothermal fluids and/or interaction with lithologies encountered during fluid migration; the level of crust at which Au deposition occurred likely migrated upward with the thermal anomaly caused by hydrothermal fluid upwelling, eventually reaching the level of current exploitation. Cessation of fluid flow along the vertical structures is attributed to inadequate recharge of the hydrothermal systems as fluid contents were depleted in the lithologies proximal to the vertical structures and/or sealing of the structures by mineral deposition."

Jan 1, 1990

By M. E. Wadsworth, T. L. MacKay

Sintered UO, samples were leached in sulfuric acid solutions of various concentrations. A pressurized system was used so that it was possible to investigate the kinetics of the reaction to 270°C with oxygen overpressures as high as 900 psi. The rate was observed to be a function of the concentration of hydrogen ions and directly proportional to the partial pressure of oxygen. Evidences are presented which indicate that a UO2 surface site reacts with a molecule of water to form a hydroxyl complex which in turn can dissociate with the characteristics of a weak acid. A rate determining step has been proposed which involves the reaction between an oxygen molecule and the hydroxyl complex on the surface of UO,. ThE 2 principal methods for uranium dissolution are carbonate and acid leaching. The sulfuric acid leach is the more popular and is used for the treatment of the majority of the ores of Africa, Canada, and the United States. Low recoveries in basic leach circuits led investigators at the University of British columbia1 to study leaching of uranium ores in pressurized vessels. Early in the study of dissolution of uranium it was found that only uranium in the hexava-lent state could be leached in acid or basic circuits. Therefore, the use of oxygen over-pressure in an autoclave offered an interesting approach to solving the low recovery problems of carbonate leaching. UO, was used in this study because it could be obtained in high purity and also because it is representative of the most refractory of the primary uranium minerals. A pressurized system was used to provide a means whereby important temperature and pressure parameters could be varied for the evaluation of the kinetic processes. The mechanism for the dissolution of UO2 should be similar for any of the uraninite type minerals. At the present all of the kinetic studies that have been conducted have been in carbonate media. Peters and Halpern2 carried out a kinetic study of the leaching of pitchblende. Their specimens were pitchblende ores selected on the basis of high grade and homogeneity. Pearson and wadsworth3 conducted a kinetic study of the dissolution of UO2 in carbonate solutions with results very similar to those obtained by Peters and Halpern. EXPERIMENTAL The UO2 as received* was found by spectroscopic *Mallinckrodt reagent, supplied by the Atomic Energy Commission. analysis to have a purity of 99.94 pct 0.03. It was ground in a mechanical agate mortar and screened through a 400-mesh sieve. Thin flat disks of UO2 were prepared by pressing the sized powder in a specially constructed die at a total pressure of approximately 25 tons per sq in. The pressed disks were approximately 0.25 cm thick, 1.6 cm diam, and 3.5 g in weight. As pressed, the samples were approximately 65 pct of theoretical density. It was essential that a binder such as poly-vinyl alcohol be added before pressing to prevent formation of cracks when fired. It was found by trial and error that pressed disks sintered close to 1870°C in a hydrogen atmosphere, reach densities between 91 and 91.5 pct of the theoretical density. At this density the samples had no measurable porosity based upon a 2-hr emersion in boiling water. An X-ray examination of these sintered UO2 disks showed them to be identical with the original UO2 received. Reaction of UO2 with the alundum furnace core was prevented by placing molybdenum between the samples and the core according to the method of Corwin and Eyerly.4 Leaching studies were carried out in a specially designed autoclave, the details of which have been presented e1sewhere.6 The main features of the equipment as applied to a kinetic study are: 1) solution samples may be removed during the course of a single run; and 2) temperature and agitation are carefully controlled. Two-ml samples removed from the autoclave during the course of a run were analyzed for U3O8 content with a Beckman model DK-2 spectrophotometer by the method of

Jan 1, 1959

By G. W. Hodges

The Basic Oxygen Process shop at Gary Works is a three vessel shop tapping 220 ton heats. The larger portion of the heats are teemed into ingot molds with the remaining heats being continuously cast in a single strand continuous slab caster. Ingot production includes a wide range of carbon, alloy, and high-strength steels in many ingot sizes for bar, structural, plate and sheet and tin products. Individual ingot weights vary with the number of ingots per heat ranging from a high of 48 to a low of five. Caster production is primarily Riband, a proprietary low carbon grade for sheet and tin applications developed by United States Steel for continuous casting; some Riband steel is vacuum degassed prior to casting. Maintaining a satisfactory level of ladle performance on both ingot and caster heats with a high production rate and widely varied product mix is a demanding and exacting job requiring the best of equipment, materials, and, most importantly, personnel. The improving trend in ladle performance in the No. 1 BOP shop at Gary is due to a combination of factors, which will be described in the following presentation.

Jan 1, 1972

By J. G. McCullough

The paper is a general description of the U.S. lead and zinc industries as they are now compared to ten years ago and the effect of recent world-wide developments. Topics of interest concerning lead are the present and potential growth of the lead-acid battery business, the potential hazards of having one outlet for a major proportion of production, the expanding U.S. secondary lead production, the hardships of stringent hygiene and environmental regulations and the future supply and demand outlook. The present poor condition of the U.S. zinc industry caused by an oversupply of zinc metal - mostly in Europe - is discussed and also the shifting markets influenced by the automotive programs to reduce the weight of cars and the continuing high mine production due to the mixture of metals contained in the massive sulphide deposits which contain a major portion of the zinc metal reserves. This is all tempered by technical advances in die casting and the emphasis on the protecting of steel with zinc to prolong its useful life. New U.S. mine and smelter production facilities will be restrained due to lower cost foreign zinc from better grade ore deposits and the insistence by Governments for refining capacity to be constructed in the country that the ore is mined.

Jan 1, 1977

Pulverized Fuel Combustion The apparatus shown in the illustration is a complete equipment f r supplying coal to boiler and metallurgical furnaces, cement and lime kilns, dryers, and to all furnaces requiring a temperature and quality of fame under prompt and easy control. It is claimed that the Aero Pulverizer makes practicable the highest efficiency obtainable from burning coal. It makes coal burn like a gas, a flame, the physical and chemical character of which is regulable- a flame that may be elongated or shortened, thus placing the zone of highest temperature where needed- a flame that may be made oxidizing, reducing, or neutral, as occasion may require. The coal is burned as pulverized, and there is no storage of the powder with its attendant hazard. Artificial drying before pulverizing is not necessary if the coal supply be sheltered from rain and snow. Where the Aero is used, it is wholly a furnace question whether a dryer should be installed; it is not at all a pulverizing or storage question. Labor is reduced to a minimum. Slack coal at low cost yields its last B.T.U.

Jan 11, 1915

By W. M. Moon, Hugh G. Miller, C. -S. So

"Digital image processing and enhancement techniques have been applied to airborne gamma ray spectrometry data from Sudbury, Ontario. These results have been correlated and compared with the available geological maps to evaluate their usefulness for identifying lithological units. Digital processing allows the correlation of various data sets, and different combinations of images can be tested and viewed as a composite image. Composite images with pseudocolours provide an opportunity to analyze and correlate information that is not otherwise apparent in individual images. Principal component analysis has been applied to the gamma ray spectrometry data to evaluate their efficacy and relative information contents of the measured and computed data. The results of this study indicate that the combined radioelements image (obtained by combining the radioelement image and the ratio images) is effective for defining areas of relative concentration of a specific element in near surface materials. Furthermore, the composite radioelements image (produced by combining three separate radioelement images) and composite principal components image reflect large-scale lithological variations. IntroductionThe Sudbury area is a unique geological structure located in the southern Canadian Shield (Fig. 1). Because the area hosts economically significant nickel-copper deposits (Pye et al., 1984), it has been surveyed in great detail by geological and geophysical methods. In order to obtain meaningful geological infonnation about the Sudbury area, several studies have been carried out with the application of innovative mathematical techniques for geophysical modelling, and attempts have been made to integrate the multisensor geophysical data available for the area (e.g. Gupta et aI., 1984; Moon et al., 1988; Singh et al., 1993). The main objective of this paper is to apply digital image processing and enhancement techniques to airborne ganuna ray spectrometry data in order to determine their usefulness for regional geological mapping."

Jan 1, 1994

By R. L. Sandefur

Professor Kim&apos;s excellent review article1 on ultimate pit planning contains a statement of the apparently widely held but incorrect belief that "kriging provides information on the confidence limits around the estimate which no other extension technique is capable of supplying." If a geostatistical approach is valid, there are several good reasons for using kriging but uniquely provided confidence limits is not among them. If kriging is possible, then confidence limits can be calculated for any other linear estimate.

Jan 6, 1979

By Dorsey Hager

The possibilities of finding new oil pools in Oklahoma and Kansas are far from promising. In 1916, the only new pools of importance were the Franchot pool near Bixby, the Garber, and the Billings pools in Oklahoma, and the Virgil and Utopia fields in Greenwood County, Kansas. In the first 8 months of 1917, a small pool of unknown extent was opened south of the Stone Bluff pool in Oklahoma, and a pool near Casey, Paunee County, Oklahoma. In Eastern Kansas, interest has been caused by the sinking of new wells near the old Iola pool, but nothing of magnitude has yet been found. The outlook for new pools is far from encouraging, especially as geological surveys have covered all of Oklahoma and Kansas. There are a few areas where geological surveys throw little or no light on the subject, as exposures are poor, but the chances of finding new pools in such areas are slight indeed, if one can judge from the past history of such areas. So far the geologists have based their opinions largely upon the presence or the absence of geologic structure, such as anticlines, domes, and terraces, but some pools will most certainly be found where no surface structure exists, but where local changes in the sand body favor oil accumulations. However, the possibilities of new pools off structure are small, as fully 90 per cent. of the oil pools are on definite structure. In the past, it is estimated that one test in 150 "wild cats" or new tests has brought in a new field. The writer feels safe in asserting that the proportion will decrease still further, so that but one out of 500 new tests may bring in a pay well in a new area. Prom now on the principal field of work in Oklahoma and in Kansas will consist in developing the present pools. The years 1915, 1916 and 1917 saw the high peak of Oklahoma and Kansas oil production. The Eldorado and the Augusta oil fields present the largest possibilities for continued production in Kansas. These two pools have been scarcely more than one-third developed, and have greater potentialities than any of the present Oklahoma pools. In Oklahoma, pools of magnitude should

Jan 1, 1918

The mineralogy of the rocks now observed in the Nairne pyrite deposit developed under conditions of internally-controlled sulphur activity during amphibolite facies metamorphism. In the sulphide-deficient metasediments the activity of sulphur was low, and pyrrhotite developed with iron-bearing silicate minerals. At higher sulphur activity, in the sulphide-rich meta-sediments, pyrite formed in addition to pyrrhotite, and the associated silicate minerals are iron-deficient.

Jan 1, 1969