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By H. J. Booss

THERE is a considerable lack of data on thermody-namic properties of hard-metal alloys. Only two papers 1,2 give mean values of specific heat in an unknown temperature range; more recently the author3 gave more detailed information on the mean specific heat in the temperature range from 20" to -190° C.. EXPERIMENTAL 1) Method—Experimental procedure followed a method suggested by Oelsen and coworkers.4 It requires samples of some 100 g of weight. The time of measurement is prolonged (30 min) but one run allows the measurement of a lot of positions on the heat-content curve. Results4 were found to be in good agreement with "best values" given by kelley,5 Kubaschewsky and Evans,6 etal.

Jan 1, 1960

By D. W. Fuerstenau

The United States is rapidly approaching an acute shortage of minerals. According to some observers, this situation may even be more severe than the energy crisis because the US consumes nearly 30% of the world's mineral production. With the mounting competition for world mineral supplies, we can no longer take for granted that foreign mineral products will be available to the US as abundantly as in the past. In 1973, US consumption of mineral raw materials was $35 billion. Of this, $7 billion consisted of imports. Without a drastic reorientation towards the mining of domestic mineral resources, the 1973 $7 billion deficit might mushroom to $100 billion by the year 2000. Thus, a return to domestic sources of raw materials will become absolutely necessary-and will be bucking the trend of the past 25 years, characterized by capital investment for growth in multinational overseas mining operations.

Jan 11, 1975

By T. Prof. Ph. D. Egleston

THE importance of having perfectly pure metals has led me to present to the Institute a record of some of the trials that have been made to obtain these metals, and also to show one of the largest specimens of extremely thin metal plate which has ever been made. The malleability of metals varies generally directly with their purity, and hence it is only with very pure metals that thin sheets can be obtained. The competition among different manufacturers has been so great at times as to lead to expensive and apparently useless experiments in obtaining in the first instance very thin sheets, and afterwards very large and thin sheets of metal, apparently with no other purpose than that of being able to say that they had produced the thinnest or the largest thin sheet that had ever been made. These experiments were at first confined exclusively to iron, their object being to show the great dexterity of manipulation, as well as the purity of the metal manufactured. They have since been extended to almost all metals by electrical action, and have gone far beyond the limits of what was possible with purely mechanical means. The processes which have been used are rolling or hammering, electrical deposition in a vacuum, and lastly, electrical deposition on plates, easily soluble in acids. The first and last of these methods have been known and practiced for a very long time, having been used to make thin sheets of almost all the metals. The other is of quite recent application. In the iron manufacture, the strife to produce these thin sheets was commenced in the year 1865, by the Sligo Iron Works writing to a firm in Birmingham, England, on a sheet of iron containing 270 square centimeters, and weighing only 4.469 grams. For some time this was considered to be the thinnest sheet iron that could be made. T. W. Booker & Co., of Cardiff, England, however, produced a few months afterward, a sheet of the same size, weighing only 4.015 grams. This was succeeded by one rolled by Neville and Everitt, of Llannelly, weighing only 3.174 grams. This was followed by one from Hallam, of Swansea, which was 283 square centimeters in size, and weighed but 2.979 grams; and this by one rolled by R. Wil-

Jan 1, 1879

By Kendall E. Born

Production of crude oil in Tennessee during 1944 was slightly more than 9500 bbl., about 1300 bbl. more than 1943. Approximately 8000 bbl. was produced from the "Mississippi lime" in Scott and Morgan Counties. Some half dozen wells in Clay, Pickett, and Fentress Counties, pumped intermittently, produced about 1500 bbl. This production is from rocks of Ordovician age ranging in depth from less than 500 ft. to approximately 1000 ft. Natural gas was marketed from wells in Morgan and Fentress Counties for consumption in the Sunbright and Jamestown areas, respectively. The production of oil by counties is shown in Table I. Developments There were 20 completions during 1944 totaling 19,615 ft., nearly twice as much as in 1943. One well was drilling on Dec. 31, 1944. Of the 20 completions, one was a small oil well soon abandoned. Three gas wells were completed which are used locally. The completions are listed in Table 2. The distribution of tests according to physiographic divisions is given in Table 3. Cumberland Plateau There were five completions in the northern part of Cumberland Plateau. One was a small gas well in the Cooper pool 3 miles west of Oneida, but an attempt to extend the pool to the south resulted in a dry hole. The most active area in the state during 1944 was the northern Cumherland Plateau, especially in Cumberland, Morgan, and Scott Counties. Several blocks, aggregating more than 500,000 acres, were assembled and leasing was continuing in the early part of 1945. Surface work has been, or is being, carried on by at least four companies. While in an area of past oil and gas production from the "Mississippi lime," the principal interest appears to be in the essentially unexplored pre-Mississippian possibilities. The Knox dolomite group of Cambro-Ordovician age is receiving some attention as a possible reservoir. As the year closed one well was drilling on a surface structure near Lantana, 6 miles southwest of Cross-ville. This test will be drilled into the upper part of the Knox. Late in 1944, it was planned to lay a gas line from northern Morgan County to Oneida in Scott County, a distance of approximately 20 miles. Middle Tennessee Fifteen wells were drilled in Middle Tennessee. In the northeastern Highland Rim area there were 11 completions, one

Jan 1, 1945

By M. L. Requa

In the fall of 1910, the Nevada Petroleum Co., operating in the Coal-inga field in California, determined to drill a number of wells with rotary tools, in order to prove conclusively the relative value of the rotary as compared with the standard rig. At that time, the rotary was but little known in California and its proposed introduction met with considerable criticism on the part of the operators and quiet opposition among the standard drilling crews. There were few men available who were competent to handle a rotary outfit, and these few had had but little experience in California fields. Machines as then built were much inferior to those now used, being lighter in construction and of a poorer quality of material. The shells encountered at depths between 1,700 and 2,000 ft. seemed to be too hard to permit of successful drilling, and at these depths the rig was changed over to standard tools and by them completed. Because of the heavy depreciation, the time lost in converting from rotary to standard, and the comparatively small profit, it was concluded that unless in the future there was some material improvement in rotary rigs, nothing would be gained by drilling with rotary tools upon this property. Little or no drilling has been done upon the property since that time, but in the meantime a large number of men have been trained in the use of the rotary; in fact, many standard-tool men have abandoned standard drilling and, starting in as roustabouts, have become thoroughly competent rotary operators. The improvements in the machinery have been such as to remove many of the objections and the rotary drilling of to-day is in every way superior to that of 1910. In contrast, a well drilled recently by the Kern Trading & Oil Co., in the east side Coalinga field may be cited. The first 2,500 ft. was drilled in 24 days and it is confidently expected that the water string will be set with a rotary at 3,400 ft.—a record obviously far beyond that made in 1910 by the Nevada Petroleum Co. The records herewith are published with the hope that some one having more recent data will publish them so that comparison may be

Jan 1, 1915

By David Keys

APPLIED geophysics is the youngest child of that old branch of learning, that has been known from Aristotle's time as physics-the constitution and laws of nature. The mother science, with the help of mathematics, has given birth to many children, who, on becoming of age in the scientific sense, wedded more practical applications which later became known as electrical engineering, physical chemistry and acoustical engineering. Some vigorous sons still retain the family name, among which the most recent to take its place as a division of science is geophysics, which deals with the physics of the earth. Geophysics in its broad sense has many departments-meteorology, oceanography and seismology, to mention only three. Within the past 20 years, however, a special interest has arisen in the application of physical principles to, problems in geology, mining and civil engineering, with the consequent rapid growth of what has now been called "applied geophysics." Applied geophysics in this narrower sense is the application of experi-mental and theoretical physics to determine variations: and discontinuities in underground structures that cannot be ascertained from surface inspec-tion. It seems evident, then, that the physics department is the natural place in a university where the principles and methods involved should be taught and developed, for the physicist will also have had the requisite training in mathematics that the proper understanding of many methods now used will require. A knowledge of the procedure and principles, however, is not sufficient for the successful application of geophysical, methods. One may know the dynamics of flight of golf balls and of impact and yet not play a par game of golf ! The proper selection and use of the right club to suit the circumstances of the lay of the ball and an acquaintance with the possibilities and limitations of the strokes as well as the practical execution of the play is essential to a successful game. So, also, in the application of geophysical methods, it is important for the geophysicist to use the best device under the conditions presented, to know the limitations of the conclusions deduced from his physical measurements and to make the proper interpretation of the results. A knowledge of geology will be of great aid in coming to the correct con-

Jan 1, 1938

By D’Arcy A. Shock, J. G. Davis

Continental Oil Co. has spent more than four years of research on the fundamentals of recovery of potash by solution mining. This work included laboratory investigations of salt solution, brine flow, selective extraction of KC1 from sylvinite, and control of cavity geometry. Laboratory results were expanded by means of a series of field tests, and subjects such as well completion and hydraulic fracturing were added to the investigation. Both single-well and multiwell mining systems were studied in the field work. This paper discusses one field test in which potash was solution mined from a thin sylvinite ore zone in the Carlsbad Potash Basin. A two-well mining system was used for this test.

Jan 1, 1970

By Dorsey Hager

North Central Texas has recently become a center of interest for the oil men of America. The bringing in of the McClosky well at Ranger, Eastland County, and the shallow pool at Brownwood, Brown County, in 1917, has stimulated interest in this area to fever pitch. Oil men from all over the United States are now investing there. The area of present interest is shown by the accompanying map (Fig. 1). The money spent in leases runs into millions of dollars. It is no exaggeration to say that a strip of country 200 miles (321 km.) long and 125 miles (201 km.) wide, comprising some 15,000,000 acres (6,070,310 ha.), has been leased practically solid at a cost for rentals and bonuses of at least $1 per acre. The test holes contracted for will certainly number 400, at a cost of at least $5,000,000. From what has been done in the past six months, $20,000,000 at least will be spent. To pay returns on this amount of money, new production to the extent of at least 12,000,000 bbl. must be obtained. At present, the production from new fields will not average over 5000 bbl. per day; three wells at Ranger are producing 3000 bbl.; 250 wells at Brownwood produce 1000 bbl.; and the Gray well, Coleman County, is as yet an unknown factor. However, at Ranger there is every indication of developing a good pool covering from 1500 to 2000 acres (607 to 809 ha.), more or less, but the wells are deep, 3400 to 3800 ft. (1036 to 1158 m.), and cost $35,000 to $40,000 to drill. Large wells are necessary to pay for such expensive holes. As new wells are drilled, the gas pressure will be lowered rapidly, and large production need not be expected. For those oil men who expect a second Cushing or an Eldorado, Ranger holds little of promise. At Brownwood, Brown County, there are some 250 shallow wells (depths from 200 to 350 ft.) averaging 4 to 7 bbl. per day. There is a chance of an extensive producing area for these shallow sands to the southwest, and the opening of several thousand acres of shallow oil territory, and also some promise of deeper oil horizons in the Ranger horizon, but probably all under 2500 ft. At present, the lease brokers and speculators, and only a handful of oil men, have made any money. More fields must be developed, and it is more particularly with these possibilities that this paper deals. Lack of water for drilling purposes has undoubtedly held back development so far this year; this part of Texas has had a drouth for two years and there is an actual scarcity of water. Geological investigations so far undertaken cover nearly all the area outlined, and while pakt of the

Jan 1, 1920

By Carl Thieme

INDUSTRIAL specialization has rapidly created a demand for new and better alloys. A more thorough understanding of the requirements of specific industries and the discovery of processes by which it has been made possible to utilize certain metallic elements in larger quantities, together with greater purity in most virgin metals, has resulted in a great increase in the number and variety of alloys. This increase in the number of elements entering into non-ferrous alloy manufacture has increased the contamination in secondary metals, as received by the smelter. In order to successfully refine scrap of a much more complex nature it has been necessary for the smelter to install new equipment and to constantly search for new methods of refining as well as to improve the methods already in use. In some instances it is largely responsible for specialization in the secondary metal industry. It is usually necessary to remove the contaminating impurities in scrap or eliminate to a degree not objectionable, no matter how introduced. In order to know what metals or elements are of an objectionable nature, the smelter must make a study of the effect of single elements and combinations of elements on many of the physical and mechanical properties, such as strength, ductility, color, hardness, casting soundness, etc. The smelter of secondary metals must be able to utilize scrap materials of all kinds, for, sooner or later, most fabricated metal parts and the waste products formed during the process of manufacture find their way to the smelter. In addition, the smelter, in contracting for salvaged material from the producer, gets some undesirable and unusual materials. The value of secondary metals and the importance of their recovery has increased in recent years and it is no longer sufficient to recover the base metal only, such as copper from copper-bearing material, but it inessential that other elements present be recovered and converted into useful form.

Jan 1, 1928

By Edward A. Sayre

In shaft sinking for cod mines, the cost item greatly influences the method adopted. This holds true especially when soft material must be traversed. The average life of a coal mine is short. This is due either to the limited area of the coal basin or to the great expense of maintenance and haulage underground when the entries are extended a considerable distance from the hoisting shaft. Therefore, the engineer in opening a coal mine is confronted with the fact that the cost must be kept within certain bounds else the venture will prove unprofitable. For this reason he may be prohibited from adopting certain safe, but expensive, methods that are used in sinking caissons for foundations, driving transportation tunnels, or other work of permanent construction. A common method of sinking through difficult ground employs the aid of a steel shoe pushed ahead of the shaft timbers. Another is the drop-shaft method. These two methods were used in sinking the main shaft and the air shaft of the Eagle No. 3 mine, at Des Moines, Ia., and the following data show the relative success and cost of the two methods of sinking under the same conditions. A drill log of the material to be penetrated was as follows (see Plate 1, Fig. 1): Thickness, Total Depth, Ft. In. Ft. In. Drift................................... 38 38 Sand..................................... 2 40 Drift.................................... 2 6 42 6 Jointed clay.............................. 5 6 48 Drift, firm............................... 10 6 58 6 Clay, with sand streaks.................... 3 61 6 Sand.................................... 12 73 6 Shale, with two thin beds of coal and thin strata of rock......................... 86 6 160 Rock.................................... 5 165 Coal..................................... 3 9 168 9 Main Shaft Sunk by Steel-Shoe Method This record shows the first 73 ft. to bc of drift material, the lower 12 or 15 ft. of which was sand. The remaining 92 ft. to the coal was shale and rock, and offered no trouble in sinking.

Jan 1, 1917

By Terry G. Richard, Vernal H. Kenner, Sunder H. Advani

This paper presents and discusses the results of thirty-one fracture toughness tests on Pennsylvanian Age Clay Shale. Two different orientations for this anisotropic material were studied and two series of tests were conducted, namely, 1. a test series to determine the effect of moisture content on fracture toughness, and 2. a test series to study mixed mode fracture. Increased absorbed moisture is found to reduce fracture toughness. Several analyses of mixed mode failure are found to give varying non-conservative predictions of failure stress intensity level.

Jan 1, 1982

By C. M. Nickerson

In times of overproduction such as the operators have been struggling against for the past several years it is the practice of the oil industry to shut in certain wells in order to reduce the flood of oil. The purpose of this paper is to present certain variations in production of oil wells when the offset wells are shut in. The scope of the study has been confined to California fields, and more especially to those of the San Joaquin Valley. The accepted definition of a shut-in well is a well where production has been suspended by closing in the casinghead arid tubing or by cessation of pumping. The immediate effect of such a procedure, of course, is to reduce the oil production from the lease, which is the result desired. However, it appears that certain types of wells vary widely in production of oil, gas and gasoline after adjacent wells have been shut in, which variation has a very material effect on the ultimate recovery of oil from the property. The increase or decrease in the oil production itself may not be of sufficient volume to occasion comment, but wide fluctuations in the gas and gasoline recovery under the changed conditions arc of the utmost importance in the future recovery of oil. The scope of this paper includes: (I) the effect on producing oil wells of shutting in offset wells, the wells being studied in three groups arranged according to their relative stages of depletion; (2) probable source of excess gas and the effect on the ultimate recovery of oil; (3) suggested procedure when wells are shut in; (4) methods that could be employed to prevent undue migration of gas from the shut-in area; and (5) the need for future studies of the situation. Three Classes of Producing Oil Wells For the purposes of this paper producing wells in California have been arranged in three groups according to the age of the well, or to the relative stage of depletion of the producing zones. The first group consists of those wells with a high fluid level, or in other words those wells whose fluid levels are a considerable distance above the top of the perforations. This type of well is in the flush period of its life and ordinarily produces

Jan 1, 1929

By W. L. Falke, A. A. Cochran

A basic problem in connection with manganese is to find economical ways to utilize domestic resources. As a part of its program to conserve domestic mineral resources and to reduce dependence of foreign sources, the Bureau of Mines had conducted extensive research to broaden manganese technology and to find economical, technically-feasible processes for recovering manganese from these low-grade resources. This paper analyzes some of the major difficulties which have been encountered in previously proposed processes for treating low-grade manganese ores and discusses a process which may circumvent many of these difficulties. Vast deposits of low-grade manganese ore exist in the U.S., yet domestic production is insignificant compared to the more than 2 million tons of ore imported yearly into this country.' A basic problem in connection with manganese is to find economical ways to utilize domestic resources.2 As a part of its program to conserve domestic mineral resources and to reduce dependence on foreign sources, the Bureau of Mines has conducted extensive research to broaden manganese technology and to find economical, technically feasible processes for recovering manganese from these low-grade resources. Although a great many processes have been proposed for treating domestic manganese resources, a failing of many of them is that too many steps are involved for economical operation.' Some of the major processes that have been proposed were reviewed by Norman and Kirby.3,4 Chlorination processes have become increasingly useful as a means of recovering valuable metals from raw materials, because the relative cost of chlorine (Cl2) and hydrogen chloride (HC1) has decreased through the years, and because the corrosion resistance of materials of construction has been improved. The objective of these processes is to form metal chlorides that are more volatile or water-soluble than are the corresponding oxides or sulfides; these compounds then can be separated from the gangue or other minerals by volatilization or leaching. Several chlorination processes for the recovery of manganese have been investigated by the Bureau of Mines5-8 and others; the major chlorination processes were reviewed in 1963, and their main features were compared.4 In all these processes, the simultaneous leaching or volatilization of iron chlorides with manganese chloride (MnCl2) is a problem, and the more iron that is present, generally the greater the problem. The leaching step is not highly selective, and the product of this step is, at best, suitable only for the production of ferromanganese or for further processing to remove iron. The product of the volatilization step is, in all cases, a mixture of iron and manganese chlorides that contains too much iron even for ferromanganese production, and must undergo additional processing steps for iron removal. THERMODYNAMIC CONSIDERATIONS The literature indicates that the desired chlorination reactions will proceed at practical rates at temperatures near 1200°K (927°C). Free energy changes at 1200°K for the critical steps of the reduction and chlorination reactions9-11 follow: Most of the research on chlorination processes for manganese recovery has been done with HC1 rather than with C12, for the following three main reasons: 1) Recycling of the chlorinating agent, which is economically vital, appeared to be easier for HC1

Jan 1, 1968

By A. H. Larson, R. J. McClincy

ALTHOUGH arsenic has a very high vapor pressure and vacuum distillation appears to be a likely method for its removal from lead, the published literature contains virtually no information concerning the vacuum removal of arsenic from lead. Caldwell, Spendlove, and St. Claire1 mention arsenic in their investigation of the removal of volatile metals from lead by vacuum distillation. They do not, however, give any data for arsenic removal or refer to any actual experimental work involving arsenic dissolved in lead. Moriyama, Kozuka, and Miura2 have determined the activity of arsenic in dilute As-Pb alloys in the temperature range from 450" to 600°C using a closed galvanic cell. They found that the activities of both arsenic and lead showed a positive deviation from ideality at 600°C. In view of the lack of experimental data regarding the vaporization of arsenic from As-Pb alloys, a limited vapor pressure study was made on liquid alloys containing from 0.5 to 3.3 wt pct As in lead at 703°C. The pressure of As4(v) above the alloys studied was determined from weight-loss data collected by means of the inert-gas saturation method. The experimental apparatus and procedure used were similar to that discussed by Alcock and Hooper9 with modifications as described by the authors., The technique involved was one of passing a known volume of inert gas over the alloy to be studied in a known amount of time and determining the loss in weight of the sample. Because of the low vapor pressure of lead at 703"C, the observed weight loss could be attributed solely to the vaporization of arsenic as the tetratomic molecule AS43 Measurements of the apparent vapor pressure were repeated at different inert-gas flow rates until from three to five values were obtained which were independent of inert-gas flow rate. This value of the apparent vapor pressure was taken to be the equilibrium vapor pressure of the alloy under consideration. The vapor pressures measured in this investigation have been converted to the activities of arsenic in As-Pb alloys, Table I, by use of the data compiled by Elliott and Gleiser5 for the vapor pressure of pure arsenic. The standard state for arsenic was chosen as the pure, hypothetical, supercooled liquid. The activity of arsenic was calculated from the fourth root of the ratio PAs,/PAS,. The low magnitude of the vapor pressures given in Table I explains the difficulty en- countered by earlier workers in successfully vacuum distilling arsenic from very dilute As-Pb alloys. The data shown in Fig. 1 indicate that the As-Pb system behaves ideally. The apparent outlier represented by the alloy containing 1.43 mol pct As is a result of the fact that the pressure of As, above the alloy was barely detectable by the experimental procedure used in this investigation. Because of this, the apparent vapor pressure determined for this alloy could be in considerable error. Moriyama, Kozuka, and ~iura' have reported that arsenic shows a positive deviation from ideality in dilute solution in lead. However, details of their results have not been made available. This research was made possible by a grant from the National Science Foundation (GK-196) for which the authors are very appreciative.

Jan 1, 1970

By E. B. Brauer, B. F. Pennington, E. W. Hough, G. L. Stegemeier

Interfacial tension divided by the difference in density between the liquid and the vapor phases was determined experimentally by the pendant drop method on several isotherms in the two phase region below the critical point for the methane-normal decane system. The density difference data of Sage and Lacey was used in the calculation of interfacial tension. Both interfacial tension and and interfacial tension divided by density difference were found to vanish at the critical point. Interfacial tensions of less than one dyne/centimeter were observed as far as 1,000 pounds per square inch below the critical pressure. EXPERIMENTAL PROCEDURE The interfacial tension divided by the density difference for the methane-normal decane system was determined at the 100°, 130°, 160' and 190°F isotherms, from pressures of about 1,000 psi to the critical pressure, which is more than 5,000 psi for these isotherms. Particular emphasis was placed upon the investigation at pressures slightly below the critical pressure where the interfacial tension is less than 0.5 dyne/cm. Volumetric properties in the two-phase region, including the critical pressures and temperatures, were taken from the work of Sage and Lacey.1 The experimental pendant-drop technique used for the determination of interfacial tensions at high pressures incorporated the ideas of Michaels and Hauser,2 Hough, et a1,3 Walker4 and Heuer.5 In addition, the technique for determination of extremely small interfacial tension by Jennings6 was utilized in the region near the critical points. A detailed description of the apparatus is given in a dissertation by one of the authors.7 Cleaning operations on the stainless-steel sample system included successive washings with chromic acid, tap water and, finally, distilled water. Subsequent cleanings were performed with re-distilled normal pentane, which had an extremely low residue upon evaporation. Specific composition requirements necessitated a fairly precise sample introduction — although, fora two-phase, two-component system, the composition of each phase is completely determined if pressure and temperature are controlled. The normal decane was delivered into the evacuated sample system as a liquid from a burette. The methane was then introduced into the system from a calibrated isothermal container, so that pressure differentials could be used to determine the amount introduced. High pressures were obtained by compressing the sample with a mercury injection pump until the critical pressure was reached for the particular isotherm being studied. Experimental data were then obtained for specific pressures by first decreasing the pressure slightly so that two phases would appear, and then photographing a drop at that pressure. Subsequent photographs were made at increments throughout the pressure range. Calculation of interfacial tension divided by density difference was made from measurements

By W. H. Ashby, R. W. Cassingham, C. R. Blomberg, J. B. Justins

The Brookhaven field is one of several Basal Tuscaloosa reservoirs located in south-central Mississippi. It is a standstone reservoir, of erratic deposition and with several faults, having an approximate subsea depth of 9,800 ft. A large variation in permeability exists with a weighted average being 256 md. Estimated average interstitial water saturation is 45 per cent. The undersaturated reservoir fluid exhibits marked differences in physical properties with measured saturation pressures ranging from 733 to 2,255 psi. Early rapid decline in reservoir pressure caused the operating interests to unitize the field and initiate a program of pressure maintenance by gas injection. At the time gas injection was commenced, the reservoir pressure had fallen to nearly half of the original pressure with only 4.5 Per cent of the original oil in place produced. The reservoir pressure has since been maintained at approximately 2,750 psig, and cumulative production to date is 17 per cent of original oil in place. An analysis of field performance during gas injection is presented in detail. The program of pressure maintenance by gas injection is considered to be a success, since the expected ultimate recovery has been increased and the current production rate is in excess of 2 per cent of original oil in place per year. Performance has been better, anticipated ultimate recovery is larger, and total production costs are lower than for a similar Basal Tuscaloosa reservoir nearby, even though that field appears to have a more effective natural water drive. INTRODUCTION The history of the Brookhaven Unit is a testimonial for unitization and for the application of engineering techniques in the operation of an oil field. The operating and royalty interests in this field have mutually benefited from their early recognition of the need for unitization and pressure maintenance and from the forthright manner in which these were accomplished. The tangible benefits accruing to the participants in the Unit are: (1) income from gasoline plant products, (2) reduced lifting and operating costs from those of competitive operation, (3) maintenance of high levels of current income by mitigation of the inevitable decline in production rates inherent to natural depletion, (4) an increase in ultimate recovery of about 40 per cent over natural depletion operations. This paper should properly be considered a progress report; however, the performance of the field after five years of pressure maintenance clearly indicates that the ultimate success of the project is assured. LOCATION AND GEOLOGY The Brookhaven field is located in south-central Mississippi, about six miles from the town of Brookhaven. Production at Brookhaven

Jan 1, 1955

By R. G. Hawthorne

This report is concerned with fluid displacement in porous media, in those cases where viscous and gravitational forces control the displacement. Such a system would usually be found in a sand body of large physical dimensions such as an oil reservoir, although it is possible to create such a system in the laboratory. It is shown that the position of the fluid interface can be predicted by numerical calculations using a basic idea presented by Dietz. Fluid flow is considered in a vertical plane in a homogeneous, porous medium of sufficient thickness that the capillary transition zone is small in comparison with the total reservoir. A theory developed by Dietz' is used to make numerical calculations of the position of the fluid interface. The results for several conditions are compared with scaled model experiments. The results show that, for gas drive in a reservoir of steep dip, a relatively low flow rate can displace large volumes of oil before gas breakthrough. On the other hand, water injection at favorable mobility ratio and low dip may show best performance at high rates. Water tends to underride the oil and, given sufficient rime, will break through without much oil displacement. For certain conditions, which include relatively low flow rate, the interface is a straight line and its behavior is simple to calculate. At higher flow rates, the interface is unstable, and a numerical solution was programed for an automatic computer. In general, good agreement is shown between the fluid model and the computed results so long as gravitational forces have control. For a water drive at very unfavorable mobility ratio, many small water fingers appear. These viscous fingers are not controlled by the relatively small gravitational forces. When viscous fingering becomes the controlling factor, the mathematical model is oversimplified, and results do not check the fluid flow model. INTRODUCTION Present methods of reservoir analysis depend upon certain simplifying assumptions to obtain mathematical descriptions of practical use. Material-balance methods (Muskat2 or Tarner2) assume uniform fluid saturations in the entire reservoir, or in a few subdivisions of the reservoir. An unsteady-state flow calculation by West, er at considered pressure and saturation changes in flow to a well during solution gas drive, and neglected gravity effects. Results showed only a 4 per cent difference for ultimate oil recovery by the Muskat method, even though the case chosen for study was one in which unsteady-state effects should be high. The Buckley-Leverett5 method commonly assumes a one-dimensional flow system. It is applicable at high flow rates where viscous forces predominate over gravity forces. Simultaneous, parallel flow of the two fluids is assumed, and the concept of a fluid interface is not introduced. Permeabilities to each fluid for a given saturation must be known. The method is not applicable for a two-dimensional system where cross flow becomes possible. Less well known is the displacement equation derived by Dietz. This method is designed for two-dimensional flow systems and assumes a definable fluid interface within the porous medium. Dietz showed that, for a range of low flow rates, the interface would be stable. straight and at an angle of inclination which could be simply calculated. At a certain critical flow rate, the calculated interface tilt would equal the formation dip. For higher flow rates, a finger of displacing fluid would invade the displaced fluid. Dietz indicated that his method applied only to macroscopic reservoir behavior, while the Buckley-Leverett method applied to the small transition zone at the fluid interface. The examples worked out in this report are based on the fluid-displacement theory of Dietz. It is shown that the Dietz theory may be used to derive equations analogous to the Buckley-Leverett equations. In contrast to the Buckley-Leverett method, flow is considered in a plane rather than being limited to a line. Rather than a frontal advance, the movement of a fluid interface is followed. For flow rates substantially exceeding the critical rate and for high viscosity ratio, many fingers of invading fluid occur-—rather than the single finger assumed by Dietz. On the other hand, so long as some gravitational influence remains, the flow is not entirely parallel to the bedding planes as assumed by Buckley and Leverett; therefore, both methods fail to give an adequate descrip-

By W. J. Nelson, R. B. Nance

Detailed underground geologic mapping at a scale of 1:1200 has been carried out at the Crown II Mine of Freeman United Coal Mining Co., which operates in the Herrin (No. 6) Coal Member. The roof sequence, upward from the coal, includes (1) soft, medium -to dark-gray shale; (2) hard, black, fissile shale; (3) argillaceous nodular- bedded limestone, and (4) fine-pined, shaly, water-bearing sandstone. The first unit is highly lenticular, and any or all may be missing at a given locality. The sandstone has a sheet facies and a channel facies. The Herrin Coal is eroded in channels near the Crown II Mine. Structural features mapped at Crown II include normal and strike-slip faults and limestone "bosses." Less stable roof and wet conditions are encountered where the limestone is thin or missing or where it is broken by natural fractures or by artificial openings that intersect the water-bearing strata above the limestone. Geologic mapping of the underground workings has allowed us to predict faults, fracture zones, and channels ahead of the face for this mine. Some lithologic and structural pattern apparently are random and cannot now be projected. Conventional exploratory drilling is entirely inadequate to map faults or lithology of the roof, but it does indicate the range of lithologic variability, which can be used to project needs for roof supports. Drilling also is useful in locating channels and in mapping regional variation in thickness and facies of the sandstone.

Jan 1, 1983

By D. F. Kaufman, H. R. Spedden, A. M. Gaudin

MANY studies of comminution have been made to ascertain the size distribution of the product and to evaluate the work of comminution in the light of the size distributions of the feed and product. Up to now, these studies have been essentially statistical in character, that is, a certain lot of feed was subjected to comminution in some specified way, and the aggregate product was fractionated into sizes, thereby losing all knowledge of individual relationship of feed to product pieces. Radioactive tracers offer a means to do something in this respect which could not be done before, namely, to follow the rupturing of some particular piece in its normal environment of other pieces. That is, it permits going beyond the usual statistical limitations of size distribution studies to what may be termed a personalized or individualized study. The purpose of this paper is to present some preliminary experiments conducted with this tool. The method employed was to mark radioactively some constituent of a feed. It is possible, of course, to consider the preparation of two lots of material of which one is radioactive and the other is not, and to blend the two ahead of the comminuting step; but to do so is open to the objection that the two preparations may not be identical. Therefore a technique has been chosen that removes this objection by merely taking out a size fraction of a comminution feed, rendering that fraction radioactive by exposure to a neutron flux, and then by returning it to Table I. Size Distribution of Offspring Albite Particles Originally 28/35 Mesh and in Admixture with Other Sizes After Grinding 2 min in a Steel Ball Mill Specific Activity ' Cumu- Corrected Distrl- latlve Size for Back- butlon In Distri- Fractlon ground, Weight, Product, button, of Product, cpm/gm g Pctb Pct Mesh (A). (W) (P) (ZP) + 28 0 56.0 0 100.1 28/35 62.6 54.0 24.8 75.3 35/48 62.8 59.4 27.7 47.6 48/65 41.1 53.0 16.2 31.4 65/100 29.6 45.7 10.2 21.2 100/150 23.7 37.0 6.6 14.6 150/200 23.3 25.1 4.4 10.2 200/270 20.1 19.0 2.9 7.3 270/400 17.8 21.2 2.9 4.4 -400 22.9 25.2 4.4 — 100.1 a These activity determinations were made in rapid succession in the order given. The specific activity (Ao) of the active 28/35 mesh fraction of the feed was measured at the beginning, after the measurement on the 65/100 mesh size fraction of the product, and; The end. The decay-corrected activities at those times were 246.7, 241.0. and 236.9 cpm per gm. The weight (W0) of the active 28/35 mesh fraction in the feed was 55.0. b Example of calculation for P in the 65/100 mesh oroduct frac- A W tion; A = 29.6, W = 45.7, Ao = 242.7, Wo = 55.0: P = — x — Ao Wo = 0.102 = 10.2 pet. the remainder of the charge for the comminution experiment. A relatively simple procedure was developed by which albite, containing sodium, was activated in the M.I.T. cyclotron. The cyclotron makes highspeed deuterons which impinge on a beryllium target, thereby producing a concentrated neutron flux. The mineral was exposed to this flux for 2 hr. This treatment changed enough of the sodium to sodium 24 (14.8 hr half-life, 1.4 mev ß) as to make detection and measurement easy. The nuclear reactions taking place were: 11Na23 (n,?) 11Na24 (irradiation) 11Na24 ß,?,? 12Mg24 (decay) The detailed technique of the experimentation was as follows: 40 kg of hand-sorted, lump albite were crushed to pass 10 mesh. After careful mixing of the lot, a screen analysis was made. The whole lot of material was fractionated on standard Tyler screens from 14 down to 200 mesh. Samples for experiments were compounded from these fractions in accordance with the screen analysis. When it was desired to make an experiment in which, for example, the 28/35 mesh size fraction was to be studied, the blend of size fractions was made as indicated above, except that the 28/35 mesh size fraction was added only after irradiation in the cyclotron. The blended charge containing the activated albite was ground for 2 min in a laboratory ball mill with a steel ball charge of controlled size distribution. The ground product was carefully sized on a set of Tyler screens in a Ro-tap. Each size was analyzed for radioactivity by the use of an end-window Geiger-Mueller counter and standard scaling circuit. This analysis was carried out in detail as follows: a 20-g sample was placed in a Petri dish, packed carefully to obtain reproducible geometric distribution with reference to the Geiger-Mueller tube, and the activity was counted for a 2-min period. Several determinations of the activity of the active size fraction in the feed were made at various times to establish the decay in activity with time. Linear interpolation was used to evaluate the activity that the active size fraction in the feed would have had at any given instant. The ratio of the observed activity in a size fraction of the product to the activity that the active size fraction in the feed would have had at the same time gives the fraction in the product size that came from the irradiated size in the feed. The general formula for finding the distribution, P, of a specific individual size fraction in the feed

Jan 1, 1952

By C. Everard Arnold

The Giroux Consolidated Mines Co. is equipping a five-compartment shaft at Kimberly, Nev., which will serve the Alpha mine. The depth of this shaft, January, 1910, is 963 ft., and of this depth 948 ft. was opened by raising; 15 ft. of sinking was done so that the bearers, collar-set, and three shaftrsets might be installed and concreted, and with this done it mas possible to erect the necessary surface-equipment for resuming shaft-timbering on the completion of the raise. The arrangement of the shaft-timbering is shown in Fig. 1. At the 1,000-ft. level of the Alpha, and 750 f't. SW. from the Alpha shaft, a 14- by 18-ft. station was cut, and a 25-h-p. airhoist was installed. From here the raising commenced on July 5, 1909. The raise was cut approximately 13 by 21 ft. in area, and supported by timbering with square sets, illustrated in Fig. 2, which shows the division into four compartments. The end compartments, which were used as chutes, had the center girts heavier than in the others on account of the wear from falling rock. The chute-lining was braced by inserting 8- by 8-in. stiffeners parallel to and half way between successive caps. Similarly, the lagging on the wall sides of the cage-way and the compartment for pipes and ladder was stiffened with 4- by 6-in. timbers. In the pipe-and-ladder compartment the chute-stiffeners were reinforced with 8-by 8-in. struts, and as the cage-way was partitioned off by braced lining, there was practically no chance of rock entering the ladder-way in case a chute burst into the cage-way. Over the two center compartments the last two sets were always bulkheaded with 8- by 12-in. timbers, shown in Fig. 3, and from the lower bulkhead the cage sheave-wheel was suspended. After a round of holes had been blasted and the loose

Jan 1, 1911