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By Lincoln F. Elkins, John T. Cooke

Injection of gas to increase oil recovery has been considered for almost all important discoveries during the past ten or fifteen years. However, the number of gas injection projects having sufficient history and data is too limited to permit valid generalities of effectiveness of gas injection. Management and engineers are faced with a difficult problem of selecting those reservoirs which are susceptible to profitable application of gas injection. Injection of gas to maintain high pressure favors some factors affecting reservoir performance such as viscosity, surface tension, and formation volume factor of oil by keeping gas in solution and favors some operating features such as extending flowing life of wells and storing part of the produced gas for future use or sales. Injection of gas at low pressure involves lower compression ratio, or at least a single gas-gathering system, larger displacement volume in the reservoir per unit of gas handled, and permits effective utilization of the naturally existing energy and agent for oil displacement that is gas dissolved in oil. Each program is thus a compromise to meet optimum economic conditions while striving to attain maximum recovery of this important nautral resource. The statement has often been made that pressure maintenance would greatly increase oil recovery by permitting abandonment of formation oil inflated with gas in solution rather than abandonment of the same liquid volume of tank oil, if the same terminal oil saturation could be attained. Simple calculations indicate increases in oil recov- ery as high as one hundred per cent on this basis for high formation volume factor oil encountered in current deep drilling. Important in this statement is "if the same terminal oil saturation could be attained." Implicit in this statement are the requirement of physical

Jan 1, 1949

By John T. Cooke, Lincoln F. Elkins

Injection of gas to increase oil recovery has been considered for almost all important discoveries during the past ten or fifteen years. However, the number of gas injection projects having sufficient history and data is too limited to permit valid generalities of effectiveness of gas injection. Management and engineers are faced with a difficult problem of selecting those reservoirs which are susceptible to profitable application of gas injection. Injection of gas to maintain high pressure favors some factors affecting reservoir performance such as viscosity, surface tension, and formation volume factor of oil by keeping gas in solution and favors some operating features such as extending flowing life of wells and storing part of the produced gas for future use or sales. Injection of gas at low pressure involves lower compression ratio, or at least a single gas-gathering system, larger displacement volume in the reservoir per unit of gas handled, and permits effective utilization of the naturally existing energy and agent for oil displacement that is gas dissolved in oil. Each program is thus a compromise to meet optimum economic conditions while striving to attain maximum recovery of this important nautral resource. The statement has often been made that pressure maintenance would greatly increase oil recovery by permitting abandonment of formation oil inflated with gas in solution rather than abandonment of the same liquid volume of tank oil, if the same terminal oil saturation could be attained. Simple calculations indicate increases in oil recov- ery as high as one hundred per cent on this basis for high formation volume factor oil encountered in current deep drilling. Important in this statement is "if the same terminal oil saturation could be attained." Implicit in this statement are the requirement of physical

Jan 1, 1949

By J. M. Steininger

The mechanism of flotation of sphalerite with sulthydryl compounds of different acidities has been interpreted in terms of chemisorption of unionized collector molecules on hydroxylated zinc surface sites. At a constant collector concentration of 1.5 x 10 -4 M, the upper pH limit of flotation has been found to be directly and closely related to the negative logarithm of the collector acidity constant, pKa The experimental results indicate that flotation is prevented when about 95% of the collector is ionized. At low pH, collector adsorption decreases because of the reduction in number of hydroxylated zinc surface sites. These two effects explain why sphalerite does not float with the more acidic sulfhydryl compounds. Typical anionic collectors for sulfide minerals are short chain xanthates or dithiophosphates which are nearly completely ionized in the generally alka- line flotation circuits.1,2 Flotation mechanisms have therefore been usually interpreted in terms of ionic collector adsorption and competition with ionic depressants of the same sign as the collector. A few attempts have been made, however, to consider adsorption of neutral collector molecules. Contact angle measurements obtained by Wark and cox3 have been interpreted by Cook and Nixon4 as representing adsorption of the free acid molecules on sulfide minerals such as pyrite, galena, chalcopyrite, and sphalerite. Cook and Nixon tried to show that the free acid concentration of the collector was substantially constant along the curves relating collector addition and minimum pH for bubble adherence. However, in a review of the subject,5 Sutherland presented new data on the flotation of pyrite with mercaptobenzothiazole which did not support the hypothesis of constant concentration of either collector ions or collector free molecules. He further showed that, with the assumption of constant occupation of surface sites, both theories lead to relations between pH and collector addition having similar mathematical expressions. In fact, with the more likely assumption of variable occupation of surface sites which results in more complex relationships, it appears impossible to

Jan 1, 1968

By R. R. Nash, W. F. Sheely, E. D. Levine

ThiS note reports on the variation with temperature of critical stress for basal slip of binary solid-solution single crystals of indium and of thorium in magnesium. PROCEDURE Alloy single crystal spheres were acid machined to 3/8-in. diam cylinders with the basal planes of the crystals normal to the cylinder axis and then annealed at 810°K. Stress was applied parallel to the slip system, (0001) [1120]. Experimental details will be presented in another paper.' Two nearly equivalent' techniques of stressing were used. Stress on the magnesium-indium alloy crystals was increased by 1 g per sq mm at 1-min intervals, and the critical flow stress was defined as the lowest stress to pro-

Jan 1, 1960

By B. F. Peters, J. Gordon Parr, E. R. Macgregor

A SERIES of seven hypoeutectoid alloys, up to 18.2 atomic pct Mn, was made by the levitation melting technique. The loss of weight on melting was considered to be entirely due to volatilization of manganese, and compositions were computed on this basis. Filed samples (—200 Tyler mesh) were helium quenched from 1000°C after soaking for 5 min by a technique already described.' Quenched Alloys -Assessments of the amounts of a phase produced and the hardness of the quenched alloys are summarized in Fig. 1. The experimental techniques and calculations involved have been described previously. The amount of a decreases as manganese content increases, until at 10.6 pct Mn only a trace of a' is observed. Previous

Jan 1, 1957

By T. A. Simpson

The search for ore continued at its relentless pace throughout 1967. Canada, South Africa and Australia plus a few scattered localities on the globe reported minerals finds of significant importance. Many of the reported finds were not high grade ore, but they nonetheless will assist in sup- plying a highly industrialized, mineral hungry world. No longer does inaccessibility and remoteness close an area to mineral exploration and development. The communication and transportation systems of today have closed the gap and, moreover, the demand for essential mineral commodities is causing price shifts which encourage exploitation of deposits heretofore considered uneconomical.

Jan 2, 1968

By John Birkinbine

Through the partiality of my fellow-members I have been able, during seven years' service on the Council of the American Institute of Mining Engineers, to note the development of technical societies, a subject which commends itself as an appropriate theme for me, in retiring from the office of President, at a time when we meet in convention with Canadian technical societies. Our next assembly, called at Chicago at the time fixed for an International Engineering Congress, offers additional reason for the selection of this topic. If subsequent statements appear to give to the American Institute of Mining Engineers greater prominence than to kindred organizations, they may be excused upon the ground of long association with and loyalty to its members, and to a personal knowledge of their work. Besides, data as to its growth and development are more accessible; and at a meeting of the Institute features connected with it may be considered as of greater immediate interest than those affecting other organizations. The purpose of this address is, however, to use the record of the Institute as indicating a similar development of other technical societies, rather than to claim preeminence for any organization; the work of each must speak for it. There is a general tendency to form associations at the present time. Organizations have been created and are active in every profession and in all branches of labor, trade, industry, commerce, manufactures, science and art. A record of such associations and their aggregate membership would be startling, and would show how large a percentage of the population of North America is connected with one or more of them; but the figures cannot be even approximately estimated. The class of associations representing national, state, or local trade interests, such as boards of trade, chambers of commerce, etc., may be used as an illustration. A late report shows that in the

Jan 1, 1893

By Finn Ouchterlony

A simple bilinear R-curve description of crack extension resistance is applied to the testing of sub-size rock core specimens. The K-curve consists of a linear sub-critical part and a flat post-critical part. Formulas for the apparent energy rate resistance quantities Gm, Jm, and [R] are developed. Experiments on notched cores of Ekeberg marble, Bohus granite, and Stripa granite are compared with these predictions. The R-curve model gives reasonable results for Gm -data but fails essentially to describe the Jm and [R]-data. Another model with a sharply increasing linear post-critical part could possibly account for the [R]-data, but direct R-curve measurements seem a better approach.

Jan 1, 1982

Alder, John W., Student, Mass. Inst. of Tech Cambridge, Mass. '38 Allen, Charles F Mines McFarland, Cal. '34 Anderson, Norman John, Student, South Dakota School of Mines Rapid. City, S. D. '32 Ansel, Gerhard, Student, Mass. Inst. of Tech Cambridge, Mass. '34 Arakelian, Haig Mark, Student, Inst. of Tech Cambridge, Mass. '34 Archer, George K., Student, Colorado School of Mines Golden, Colo. '34 Arnot, Paul H. 608 S. Acacia St., Compton, Cal. '31 Asel, Philip R., Student, Colorado School of Mines Golden, Colo. '32 Augenthaler, Robert L., Student, New Mexico School of Mines Socorro, N. M. '32 Augustine, Robert W. Address Wanted. '32. Austin, Robert B., Student, Univ. of Idaho Moscow, Idaho. '34

Jan 1, 1934

By Sherwin F. Kelly

GEOPHYSICS may be considered a vice (albeit, I submit, a comparatively harmless one) whose career is aptly described by Pope's lines: Vice is a monster of so frightful mien, As to be hated needs but to be seen; Yet too oft, familiar with her face, We first endure, then pity, then embrace. Although there may be some that have not yet succeeded in emancipating themselves from the first stage of horrified contemplation, geophysicists may be duly thankful that there are mining men and geologists that have arrived at a state of apparently irretrievable damnation.

Jan 1, 1936

By W. S. Ayres

I. INTRODUCTION. THIS cavern was discovered Oct. 22, 1904, by Mr. Charles H. Deutschman, in company with whom I made, May 29 to June 3, 1905, at the request of Mr. Howard Douglas, Superintendent of the Canadian National Parks, the first exploration of it for the Canadian government. The results were stated in a paper, orally presented, with lantern-views from my photographs, at the British Columbia Meeting of the Institute, Victoria,, B. C., July 5, 1905.* The present paper embodies also the results of a second examination, made Oct. 25 to 29, 1905. The accompanying map, Fig. 1, will serve as a guide to the following description. II. LOCATION. The cavern is situated at snow-line, at the head-waters of Cougar creek, on the west slopes of the Selkirks, about 2 miles north from Ross Peak water-tank, and 5.5 miles west from Glacier House, on the main line of the Canadian Pacific Railway. It was then reached by an arduous climb from the water-tank, up the ravine of Cougar creek, for 8,000 ft. (2,000 ft. of altitude) over rock- and snow-slides, and through a thick tangle of alders. But an easy and very picturesque trail has, during the past summer, been opened by the government from Glacier House. Figs. 2, 3 and 4 represent views, not heretofore published, of the grand scenery of this region, so rapidly becoming the-object of attraction to thousands of tourists from all parts of the world. These views, as well as those shown in. Figs. 5, 6, 7, 8

Jan 1, 1907

By Eugene R. Rice

(Canal Zone Meeting, November, 1910.) THERE are many methods for determining the meridian, but all of those in common use involve at least two separate observations, one for latitude and one for azimuth. Such observations made upon a south star at any hour are open to the objection of possible inaccuracy due to ignorance of the absolute refraction, and also to slow change in the altitude of the star when near the meridian. The method of observing a circumpolar star at elongation, besides requiring a separate observation for latitude, is open to the serious objection that clouds may obscure the star at the critical moment. Moreover, a tedious wait for the star to come to elongation is sometimes necessary. Many of us can recall long, cold, weary vigils, waiting for Polaris to reach elongation. For observing a circumpolar star at any hour, not only the latitude, but also the true time, must be known. This it is practically impossible to obtain, except in regions reached by the telegraph, and usually then one has to know the longitude also, in order to reduce "standard time" to "local time." The results obtained by this method, when the star is at culmination, are not very good, unless the true local time is absolutely known. The methods of obtaining the meridian from the sun, by means of a solar attachment, or by direct observation, while good, are not absolute, by reason of refraction, change in declination of the sun, and small change in vertical angle, when the sun is near the meridian. For these two methods, latitude, time, and approximate longitude have to be known. In the method here described, only one observation is needed, and from it azimuth, latitude, and sidereal time are computed. In other words, one can observe a circumpolar star-Polaris

Nov 1, 1910

By Hans Lundberg

GEOPHYSICAL methods as described in technical articles generally fail to answer the questions of prospectors and geologists as to which method they should apply and what information they may expect from their application. This article is an attempt to discuss the use of electrical methods with special reference to the prospecting for orebodies and the map¬ping of geologic structure. Especially on virgin ground, geological reconnaissance should precede electrical prospecting, with the object of outlining carefully the orebearing rock and determining the possibilities of elec¬trical prospecting. No electrical survey will then be carried out on ground which, for geological reasons, may be considered barren or where the electrical meth¬ods are inapplicable. As the success of electrical prospecting depends on the difference in conductivity between the ore and the country rock within which the orebody is inclosed, the conductivity of the two should be considered and de¬termined, if possible. The conductivity of an orebody depends on the distribution of conductive ore minerals and, in addition, on its size (length, width and depth). Most minerals with metallic luster show good electrical conductivity; for instance, the sulfides. Zinc-blende is an exception, but as it is often associated with the ore minerals of good conductivity (for instance, pyrite or galena), there is likelihood also of finding zinc.

Jan 1, 1930

By J. H. Wernick

IN a study of the rate of decomposition of ½ -in. cubes of limestone, dolomitic limestone, and dolomite in a sweeping nitrogen atmosphere, Joseph, Beatty, and Bitsianesl found that the zone of calcination advanced at substantially a constant rate at a given temperature. The purpose of this paper is to show that their data indicate at least two processes occurring when the above carbonates decompose. It is suggested that there are two processes occurring temperature range and the other the limiting process over another temperature range. The data of Joseph and co-workers have been extended by use of the Arrhenius equation, Eq. 1, a relation beween the velocity constant k of a reaction and the absolute temperature T.

Jan 7, 1954

By Edgar T. Wherry

EDGAR .T. WHERRY,* Washington, D. C. (communication to the Secretary ?).-Dr. Pogue's presentation of the facts concerning the emerald deposits is very clear and convincing, and the only addition that I can suggest is a summary of previous theories of origin. He makes it evident that the pegmatite theory is the only one capable of explaining the existing relations, but upon certain details there may be some difference of opinion. If I understand the term pneumatolytic, it does not imply that all the elements concerned in a given deposit were transported as gases, but rather that the crystallization of these elements into the various minerals was favored by the presence of certain gaseous substances, notably H20, C02 and HF. It is highly improbable that the oxides of glucinum, aluminum, chromium, and silicon, which enter into the composition of the mineral emerald could have been transported in the gaseous form. The same is true of the metallic constituents of the parisite and other associated minerals. The explanation suggested, that solutions separated into liquid and gaseous portions, the latter ascending and forming the emerald in the upper portions of the rock only, therefore, seems to me untenable. When two formations exist side by side and one, A, is mineralized while the other, B, is barren, the possible explanations may he classed as (1) chemical, and (2) physical. 1. Some chemical feature of A not found in B might have caused crystallization of certain minerals in the former, which did not appear in the latter. In the present instance both rocks appear to be so similar chemically that no such effect can be looked for. Pogue mentions carbon as a possible precipitating agent, but describes both formations as carbonaceous, so that the difference in the minerals of the two can not be thus explained.

Jan 10, 1916

By Clinton H. Crane

DR. TILNEY, the great expert on the study of the development of the brain of human beings and animals, tells us that the greatest difference between the human brain and the brain of animals is that man alone has shown evidence of being able to predict the future. Just why he throws overboard the busy bee who lays up honey for the winter, the squirrel who gathers nuts, and the humble ant, I do not know. At any rate, it is nice to be assured by an authority that we have this power of prophecy. My own experience with attempting to prophesy the future has convinced me that our only possibility of being good prophets is to be good students of history.

Jan 1, 1940

US 4,201,749-In the Bayer process production of alumina wherein aluminum hydroxide is precipitated from a sodium aluminate solution for use as seed, sodium oxalate and caustic components are removed from the precipitate by washing it first with a washing liquor which is saturated with sodium oxalate but has little content of caustic, and secondly with hot water. Substantially no sodium oxalate is recycled, yet loss of sodium aluminate is minimal. K. Yamada, T Harato, and H Kato, assigned to Sumitomo Aluminum Smelting Co Ltd May 6, 1980 8 pp. (423-127). Filed. 5-8-79 (37,145) Priority. Japan, 5-8-78 (53/54,803). Same¬British 2,020,642, dated Nov. 21, 1979.

Jan 1, 1982

By Michael Tenenbaum

THE importance of semikilled steel as a high tonnage grade has long been recognized. The increasing severity of the applications for which semikilled steel is used makes it desirable to obtain further information regarding the features of open hearth practice and ingot structure that can affect steel performance in subsequent rolling and fabricating operations. Accordingly, an investigation is being carried out studying the structure of various types of semikilled steel ingots. This paper reviews some of the observations made and information gathered in this investigation. By definition, semikilled steel may be considered to include all nonrimming steels in which the natural shrinkage occurring during ingot solidification is offset to an appreciable degree by gas formation. Accordingly, this type of steel includes the entire range intermediate between rimmed and fully killed steel. The resultant ingot structures range from those of steels that have been capped to suppress a weak rimming action to those steels that have been killed in the furnace or ladle to the extent that no mold deoxidizer is required. A survey reported to the 1946 AIME Open Hearth Conference' reviewed the practices being used at 28 major plants for the deoxidation of semikilled steel. It was found that most plants divide the deoxidizing additions between the ladle and the mold many of the plants adding only minor amounts of deoxidizer to the bath or none at all. Silicon, aluminum and titanium were the only elements used for ladle and mold deoxidation. Mold deoxidizers were added as capping additions or as uniformly fed additions. Several practices were reported in which the steel was deoxidized in the ladle to the extent that little or no mold deoxidation was needed. No reference was made to grades capped by using special mold designs or special closures over the top of molds. Accordingly, specific examples of this type of practice will not be considered in this paper. It appeared from this survey of deoxidation practice that semikilled steel can be divided into three types, namely, capped semikilled, in which aluminum is added near the end of pour or after shut-off, intermediate semikilled steels, in which aluminum is fed uniformly throughout the pour, and semikilled steels requiring no mold deoxidation. In an attempt to cover the ingot structures obtained by the range of practices reported in the preceding survey, three series of experimental heats were made using increasing amounts of aluminum, silicon and titanium for ladle deoxidizers. The ladle deoxidizers were added as stick aluminum, 50 pct ferrosilicon and 20 pct ferrotitanium (4 pct carbon), respectively. Two methods of studying ingot structures were used. Ingots were removed from production, burned longitudinally and machined to allow observation of the central pipe and coarse blowholes. During the machining operation much of the finely porous subsurface structure was obliterated. Accordingly, observations were also made

Jan 1, 1947

By H. H. Klepfer, K. J. Gill, P. Chiotti

SOME observations relative to the U-Zn system have been made by other investigators. Chipman1 and Carter2 have reported the preparation of several U-Zn alloys and point out that these alloys are generally difficult to prepare. Chipman1 reported evidence for a high melting compound at about 90 atomic pct Zn and the possible existence of a eutec-tic between the compound and uranium. Raynor," in a theoretical discussion of the alloying properties of uranium, included zinc among the elements predicted to have little or no solubility in a, p, or y uranium. In the present investigation, thermal analyses, X-ray, metallographic, and vapor-pressure data were obtained to determine the phase boundaries. The relatively high zinc pressure over most of the alloys at temperatures of 900 °C and above proved troublesome and special techniques had to be employed in preparing suitable alloys. Materials and Preparation of Alloys The metals employed in this investigation were Ames Laboratory biscuit uranium containing less than 500 ppm total impurities and Bunker Hill slab zinc or Baker Analyzed reagent granulated zinc, both with a purity of 99.99+ pct. Due to the high vapor pressure of zinc and the high reactivity of both uranium and zinc with oxygen at only moderately high temperatures, alloys were prepared in closed containers which had either been evacuated or evacuated and filled with helium. High purity magnesia, magnesia containing 10 pct calcium fluoride, and tantalum proved to be suitable crucible materials. Tw-o different procedures, described below, were used to prepare alloys, the latter being the most satisfactory. The metals, uranium turnings and granulated zinc, were cleaned with dilute nitric acid, rinsed, dried, and placed immediately in a helium-fill'ed dry box. The two metals were placed' in a 10 mil Ta crucible. The charge was enclosed in the tantalum crucible by welding on a preformed tantalum cap. This assembly was enclosed inside a stainless steel (AISI 309) bomb. The bomb was made by welding a piece of stainless steel plate on each end of a stainless steel pipe. All these operations were carried out in a helium atmosphere. These assemblies were heated in a muffle furnace at temperatures between 1100" and 1200°C for 10 to 15 min or held as long as 15 to 20 hr in the 950" to 1000°C temperature range before quenching. Spectrographic and chemical analyses showed no tantalum pickup by the alloys, indicating no reaction between the alloys and the crucibles. However, some of these crucibles failed, probably due to imperfections in the welds of the stainless steel or tantalum crucibles. The second and most satisfactory method was to prepare the alloys by powder metallurgy techniques. The procedure was to press degreased and acid-etched uranium turnings with granulated zinc into 20 g compacts under 20,000-psi pressure. The compacts were placed in MgO crucibles, and sealed in evacuated Vycor or fused silica tubes. The alloys were then heated as long as two weeks at about 550°C in a muffle furnace. The pressed compacts were observed to expand by several volume percent during heating and it was necessary to make allowances for this expansion in order to avoid breaking the crucible and Vycor tube. This method was found very satisfactory for preparing alloys which were suitable for thermal analysis or vapor pressure studies. Experimental Methods and Results The phase diagram for the U-Zn system at 1 atrn pressure, shown in Fig. 1, is based primarily on vapor pressure measurements and on thermal analysis taken at temperatures below 950°C. Fig. 2 shows the U-Zn diagram at 5 atrn pressure, constructed on the basis of thermal analysis of alloys in sealed containers up to 1150°C and on the basis of metallographic, X-ray, and analytical data. The alloys sealed under vacuum were actually under their own vapor pressure and those sealed in an atmosphere of helium were under an additional pressure due to the helium. At temperatures up to 1100°C the zinc pressure is 5 atrn or less for these alloys; consequently the maximum pressure over the alloys sealed under a helium atmosphere was 10 atrn or less at temperatures up to 1100°C. Changes in pressure of this order of magnitude do not appreciably alter the position of most solid-solid or liquid-solid phase boundaries. In constructing the phase diagram for a pressure of 5 atm, the effect of pressure on all phase boundaries except those for liquid-vapor or solid-vapor regions was considered negligible.

Jan 1, 1958

By Alfred Weiss

Daniel C. Jackling's innovative concept for handling low grade ores ushered in a new philosophy of open pit mining. As one of the greatest minemakers of all times he revolutionized major segments of the industry and helped strengthen US defense efforts during World Wars I and II by making possible the tremendous copper supplies from US mines. Many great mining men have since followed in his footsteps with their discoveries of new orebodies or development of new mines. Their brilliance in leadership can also be traced to the coupling of a new idea to the physical nature of the materials in the earth's crust or to the extractive stages of minerals recovery. The minerals industry is now in another era of change and must again devise techniques to meet the challenge. The task is not only to create new exploration techniques and develop new mining methods, but, I believe, to optimally apply new concepts and tools in daily decision-making.

Jan 11, 1978