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Jan 1, 1949

By O. W. Bilharz

Acid mine-water drainage is a serious problem with many mines in the Tri-State zinc and lead mining district. Particularly is this true when large volumes must be considercd in unwatering old mines that have refilled with water which has dissolved the products of oxidation and has become chalybeate in character. The experiences discussed in this paper have to do specifically with the unwatering of a comparatively small area west of the town of Baxter Springs, Kans., where the pumping job was complicated by water of this type and where the extremely high sulphate content particularly effected that phase of mine drainage having to do with stream pollution. Location, Geology and History The Baxter Springs area of the Tri-State mining field is situated just west of the town of Baxter Springs and is a northeasterly extension of the main mineralized zones of the Oklahoma part of the district (Fig I). The mining area is traversed with well defined shear zones which provide easy circulation of ground waters and the ore bodies are found along these shear zones as localized enrichments wherever the structural conditions are favorable (Fig 2). The ore-bearing strata is Mississippian with an overlain capping of shale of Penn- sylvanian age. This shale strata carries much pyrite and marcasite at its base and undoubtedly was a contributing factor to the subsequent high iron content of the water. The area originally contained a sulphide water which discharged as an artesian flow in springs within the town and gave Baxter Springs its name. These springs were famed for many years for their mineral water. This original sulphide water was first removed about 1917 and active mining was carried on west of the town during subsequent high metal price periods. Many small mines were opened, with each localized enrichment becoming a separate mine. During the depression mining ceased and all mines in the west Baxter area were allowed to flood. No serious effort was made to again unwater until higher prices caused from the demand for metal for World War II once more focused attention 011 this part of the field. Original Mining Results in Oxidation As plans for unwatering progressed, it soon developed that the mine-water pools had become strongly acid in character and carried large amounts of sulphates in solution. This occurred in the following way. When the original sulphide water was removed, shafts sunk, and mining carried on over a number of years, ferrous sulphate was formed by the spontaneous oxidation of the pyrite beds in contact with air admitted through churn-drill holes and mine openillgs. These products of oxidation can be seen today in the old mines of the district as crusts of crystalline sulphates

Jan 1, 1949

By J. C. Fisher

C. S. Smith has described a method for measuring the relative values of different solid-solid and solid-liquid interfacial tensi0ns. When a polyphase alloy is held at an elevated temperature, individual particles of each phase adjust their shapes and minimize the interfacial energy. Wherever three interfaces meet, the dihedral angles are such that the three interfacial tensions, considered as forces, are in equilibrium. When the angles between three forces in equilibrium at a point are known, it is possible to determine any two in terms of the third. In this way ratios of interfacial tensions have been .obtained. The value of a given interfacial tension ratio was found to be independent of the alloy system from which it was determined. Smith also has employed the method when one of the phases is liquid. When equilibrium is reached with respect to In the course of work on grain growth in high purity aluminum a simple optical method was developed for detecting the presence or absence of preferred orientation in annealed specimens. The specimens were prepared by grinding, polishing and "deep etching." The etching reagent used for high purity aluminum has been described.* The resulting etch pits produced selective

Jan 1, 1949

By Lester Guttman

The connection between short-range order and thermodynamic activities in binary solid solutions has been pointed out by Birchenall1 who calculated approximate values of the energy of interaction of Zn and Cu and of the degree of short-range order in alpha-brass at one composition and two temperatures. The purpose of this note is to call attention to a somewhat more accurate theory than that used by Birchenall and to extend the calculations to a wider range of temperatures and compositions as a means of testing its applicability. This is an example of the well-known general method of comparing measured thermodynamic functions of a system with those calculated from a microscopic model by means of statistical mechanics. In this case, mathematical approximations must be used which make difficult any decision about the validity of the model. Birchenall's statistical method resembles closely that calletl by Fowler and Guggenheim2 the "quasi-chemical" method which has been shown to lead in certain cases to results identical with those obtained by the method of Bethe.3 The quasi-chemical method has been extended by Takagi4 to give general formulas for the free energy of binary solid solutions based on several lattices at all compositions and temperatures. Specifically, he treats the four systems typified by: I. ß—brass; 2. a— brass; 3. AuCus; 4. AuCu. When the temperature is so high that no long-range order exists, these formulas reduce to the same form for all lattice types, namely: F - FO = (E - EO) - T(S - S°) = ½N(c — x)(2vAB — vAa - Vbb) + M1/2KTzN[x log x + 2(c - x) log (c - X) + (I - 26 + X) log (1 - 2c + x)] -kT(z - I)N[c log c+(I-c) log (I -c)] Eq 1 Here the symbols have the following meanings: F—Helmholtz free energy E—nergy 5—ntropy k—the gas constant per molecule z—coordination number, (e.g. I2 in a-brass). N—total number of atoms c—atomic fraction of A Vaa, vbb, vab—nergy per bond of the corresponding bonds log means log, throughout The superscript ° denotes the thermodynamic fuliction in the standard state, which has been chosen to be pure A or B with the same crystal structure as the solid solution. The quantity x is the ratio of the number of A-A bonds to the total number and for minimum F satisfies the equilibrium condition Vaa + Vbb — 2Vab _ (c — x)2 kT l0g x(i - 2C + x The free energy may also be written in terms of /La and B, the chemical potentials or partial free energies per alom:

Jan 1, 1949

By M. W. Bartley, Hugh M. Roberts

Substantial deposits of Bessemer hematite have been found recently by drilling beneath Steep Rock Lake, Ontario, which is situated in the northern part of the Lake Superior Region. It will be practicable to divert the waters flowing into this lake and develop open pits on the upper pert of two large ore bodies by damming off and pumping out the water in the part of the lake in which they occur. Ultimately, the bulk of the ore will be mined by underground methods. Owing to the generally massive nature of the rocks in the area, no underground flows of major consequence are anticipated after diversion of the lake. The Steep Rock deposits are attributed in origin to hydrothermal replacement. They were formed, for the most part, along an unconform-able, brecciated contact between the Steep Rock limestone and an overlying younger volcanic series, The replacing solutions came in as igneous after-effects, following upon the intrusion of basic igneous rocks that invaded the hanging-wall volcanics. It is believed that this took place in a geological period roughly equivalent to late Middle Huronian, which was the period when the most extensive iron-bearing rocks of the Lake Superior Region were formed. Comparison is made with other deep-seated iron-ore bodies in the Lake Superior Region, the origins of which are ascribed in the discussion to hydrothermal replacement. Introduction Under the waters of Steep Rock Lake, Ontario, situated on the Canadian National Railway, 142 miles west of Port Arthur, the presence of three ore zones containing red and brown Bessemer hematite has been established. These were discovered and have been partly explored by means of diamond and churn drilling, The positions of the ore zones, designated as A, B and C, are shown on the accompanying maps and cross sections. This exploratory work, begun in 1938 by Joseph Errington* and Julian G. Cross, has been carried on by Steep Rock Iron Mines Ltd., and was continued during the winter of 1941-1942. For more than 60 years explorers have known that large quantities of hard hema. tite float of good grade existed along the south shore of Steep Rock Lake, and the presence of ore beneath the lake was inferred by many early geologists and explorers. Despite numerous previous attempts to find ore in place, actual discovery awaited the recent period of intensive exploratory effort in Canada. The results obtained in the drill holes put down since 1938 by steep Rock Iron Mines Ltd. are not only of interest, in themselves, to those concerned with the development of ore deposits, but, taken in connection with the surface exposures of adjoining formations, they form the assemblage of facts from which the geological reasoning in this paper proceeds; accordingly, they are set out here as briefly and exactly as may be.

Jan 1, 1949

By W. T. Lundy

THE forms in which sulphur is commonly found-native sulphur, sulphides of many metals and sulphates-are widely distributed throughout the world. The two first mentioned are the principal sources of sulphur. Substantial amounts of sulphur in some form are recovered from gases from industrial plants and from gases from smelters treating other minerals. In recent years, plants have been installed in the United States to recover sulphur in elemental form from sour gases."' The amount of sulphur so produced is small at the present time but undoubtedly will increase in the future. The recovery of sulphur from gases is not covered in this chapter, which is confined to: (1) native sulphur deposits of Texas and Louisiana; (2) those of Italy; (3) other scattered deposits of native sulphur; and (4) pyrites deposits found in many countries of the world.30 Sulphur, a nonmetallic element, occurs normally in well developed bipyramidal or tabular crystals of the orthorhombic system, as well as in stalactitic and earthy masses. The mineral has a distinctive yellow color, which may be dark and discolored by impurities; the streak is white; the luster is resinous; and the fracture is conchoidal to uneven. Sulphur is translucent to opaque; has a hardness of 1.5 to 2.5, a specific gravity of 2.05, and an atomic weight of 32.06.16 The molecular weight of the solid is expressed by the symbol SS and that of the liquid and vapor ranges from S2 to S8, depending on the temperature. Sulphur melts at a temperature between 2340 and 248°F, depending on its crystalline state, to a liquid of dark amber color, the boiling point of which is 832°F. The viscosity near the melting point is about that of water and increases to 50,000 times that of water at a temperature of 380°F, subsequently falling rapidly to a low figure at the boiling point. Crystallization changes slowly from rhombic to monoclinic above 205 °F and in cooling the transformation is reversed. The mineral is a very poor conductor of heat and electricity; it is insoluble in water and nearly all acids and is soluble in cold carbon bisulphide and carbon tetrachloride. It ignites in air at a temperature of 478°F, burning with a distinctive blue flame with evolution of sulphur dioxide.47

Jan 1, 1949

Jan 1, 1949

By E. F. Miller

The subject " Safe Timbering of Working Places in Mobile Loading" is one that requires an analytical study of the strata both above and below the coal seam as well as the characteristics of the coal seam itself. The projection or mining plan must be based on economic roof control in which the application of timber can be minimized without incurring cost increases in other phases of production. The several types of loading machines in common use today are not adaptable to the same projections or timbering systems. Consequently the type of equipment to be used must also be considered. For these reasons the writer does not believe that the problems of timbering in working places can be discussed without simultaneously considering economic production as well as the safety of men and the conservation of equipment. Prior to the introduction of loading machines as a substitute for the pick and shovel system of loading coal, the care and maintenance of the individual working places were generally the responsibility of the coal loaders who worked in them. Up to that time very few coal companies had developed and applied fixed and definite standards for timbering the working places in the mines they operated. It is common knowledge that mechanical loading of coal has had several false starts in the last twenty-five years and it is only in the last decade that it has developed to the stage at which we now find it. During this twenty-five year period the management of the more responsible companies have come to realize the tremendous importance of roof control in coal mining. From a safety viewpoint, the lack of roof control has been and still is responsible for more than a third of the industry's annual fatality experience. In recent years workmen's compensation and insurance rates have steadily increased while the profit margin has decreased almost to the point of elimination. From an economic operating viewpoint, the failure to properly control roof is quite often the most costly single phase of coal mining. Since the manufacturers of loading machine equipment have so improved their machines that normal care and maintenance can reduce to a minimum the time lost because of mechanical failure the production delays from other causes have assumed a far greater importance. Roof control in the broad sense and in the light of concentrated mining plans or projections that are adapted to mobile loading should be regarded as one of the major problems in the inseparable phases of production and safety of the workman and equipment at the working face. The subject of this paper cannot be treated properly unless what is said here is based upon the broad and fundamental problem of genera' roof control. The suc-cessful solution of a problem arising in any industry must have its origin in a complete analysis of the known facts or factors that pertain to it. The several illustrations

Jan 1, 1949

By Hans Neuberger

In our everyday life, visual perception plays perhaps a more important role than any of the other senses with which we are equipped by nature. It is, therefore, quite understandable that the average person associates with the term ''atmospheric pollution," clouds of dust, palls of smoke or deposits of soot, phenomena which are so familiar to the residents of industrial cities. On the other hand, "air" is usually considered the prototype of the invisible, of the intangible, and any suspensions in the air which do not conform to this concept, are regarded as foreign to the atmosphere and thus as "pollution." According to Webster, the term "pollution" implies uncleanness, impurity, in short, something undesirable. Although the scientist often accepts popular concepts, he is generally inclined to suspect that apparently "obvious" phenomena imply, literally, "more than meets the eye." To show that this suspicion is also justified with regard to atmospheric pollution, is the objective of this discussion. It will be shown that what seems foreign to the air at first sight, is by nature an integral part of it, and that the more important aspects of pollution generally escape attention. The Atmospheric Constituents We can distinguish two classes of atmos-pheric constituents: the Permanent gases, chiefly nitrogen, oxygen, traces of argon, neon, and others, and the variable constituents which include water in its different states, carbon dioxide, ozone, and various suspensions, either in gaseous, liquid or solid form. These suspensions, known by the collective term "Aerosol,"20 will be considered in detail. Dust There are two general types of aerosols: the first type is represented by the socalled "neutral" particles,3 commonly known as dust and experienced by everyone, as it is the more conspicuous type of suspensions. It often represents a special problem to the mining engineer, the mechanical engineer, the industrial engineer, and many other professional men. Dust consists of finely divided solids derived from weathering, drilling, handling and preparation of rocks and coal. Dust may also consist of organic or inorganic particles resulting from manufacture of a variety of products such as flour, rubber, lime and steel, from traffic on land be it on the highways, on rails or in city streets, from decomposed vegetation or from volcanic eruptions. Perhaps the most reviled member of this class of suspensions is the soot and fly ashes from coal fires and other combustion processes. The cosmic source of dust, namely the injection of meteoric matter into the atmos-,,here, is of minor significance because the concentration of particles is exceedingly small despite the relatively large mass of material which invades the earth's atmos-phere from space.

Jan 1, 1949

By Owen Thornton

Recently equations have been presented by Rose and Bruce' and by Rose², showing how the relative permeability of a reservoir rock may be determined from the capillary character of the rock. In particular, equations were developed to show the relationship between capillary pressure and the effective permeability to the wetting phase in a poly-phase flow system. The equations are as follows (nomenclature the same as in the Rose and Bruce paper) Rose and Bruce assume that the average length of path (L,), which the wetting fluid follows in flowing through a porous media is independent of the saturation to the wetting phase, so that 1 is a constant dependent only on the k rock, and the permeability to the wetting phase is a function of the saturation and of the capillnry pressure: In measuring the flow of ekctric current through partially saturated core samples, it has been observed that the electrical resistance usually is not a simple linear function of saturation. This fact indicates that the average length of path in the flow of electric current is not independent of saturation, but rather that the tortuosity of the path depends upon the average saturation to the conducting fluid as well as upon the characteristics of the rock. itself. Inasmuch as the flow of fluid and the flow of electric current in many respects are analogous, it may be indicated further that the length of path for fluid also may not be independent of saturation. The following relationship can be derived to express the resistance to flow of electric current through a core sample partially saturated with conductive wetting phase, the non-wetting phase being non-conductive: where L is the average length of path followed by the current in flowing through a length L of partially saturated core, where L is the length of current path when the core is fully saturated, and where Rs and R, are the specific resistivities of the partially saturated and saturated core sample, respectively. It will be noted that R., the specific resistivity of the core sample when S, = 1.0, is equal to the "formation resistivity factor"' multiplied by the specific resistivity of the saturating fluid. If it be assumed that the average lengths of path for fluid flow and for the flow of electric current are the same, then equation (5) may be combined with equations (l), (2) and (3) to give the following relationship: The above equation suggests including a correction for tortuosity when calculating the relative permeability of a reservoir rock to a wetting phase. The correction factor may be obtained from the resistivity-saturation relationship. For instance, the following calcu- lations are obtained for the unconsoli-dated sands described by Leverett Kw Kw Sw R°/Rs Pt/Pc¹ (Calc.) (Obs.) 0.30 0.08 0.88 0.02 0.0 0.40 0.16 0.94 0.06 0.04 0.50 0.27 0.97 0.14 0.11 0.60 0.40 0.98 0.26 0.21 0.70 0.53 0.98 0.39 0.35 0.80 0.68 0.99 0.57 0.54 0.90 0.84 0.99 0.77 0.76 1.00 1.00 1.00 1.00 1.00 It will be noted that the agreement between the calculated points and the observed data is rather good. Further investigation of the above method for obtaining relative permeabilities may be merited. For many sands within specified ranges of saturations the following relationship has been found to hold approximately': — =SW"......(7) Rs The exponent n in the above equation has been found to equal two for many sands so that equation (6) reduces to the following: The writer acknowledges the permission of The Texas Co. to submit this note for publication. 1. Walter Rose and W. A. Bruce—Jnl. of Pet. Tech., Vol. 1, No. 5, p. 127 (1949). 2. Walter Rose—Jnl. of Petr. Tech., Vol. 1, No. 5, p. 111 (1949). 3. G. E. Archie— -Trans. AIME, 146, 54 (1942). 4. M. C. Leverett— Trans. AIME, 142, 152 (1941). 5. M. C. Leverett—Trans. AIME, 132, 149 (1939).

Jan 1, 1949

By David J. Mack

The structures and properties of the copper-aluminum alloys have been the subject of much study since the classic investigation of Carpenter and Edwards1 focused attention on. the engineering utility of these alloys. It was recognized at an early date that the metallographic structures developed in the aluminum bronzes were similar to those developed in steels, both in the annealed and the rapidly cooled state. Most investigators have been concerned with the acicular, martensitic-like structure formed from the 0 solid solution upon rapid quenching; the transformation of the ß under equilibrium cooling to a lamellar eutectoid having been relatively neglected. With the introduction in 1930 by Davenport and Bain2 of the isothermal transformation technique for studying eutectoidal decompositions, a new field was opened. Although an enormous amount of work has since been done on the isothermal transformation of steel, study of structurally analogous systems has been almost totally overlooked. The outstanding exception was the prize-winning paper† of Smith and Lind1ief³ ho investigated the decomposition of the 0 phase in copper-aluminum alloys by isothermal methods. This was followed in 1934 by Wasserman's review' of available information on analogous transformations in eutectoid alloys. Since that time no comprehensive study of isothermally transformed eutectoids analogous to steel has appeared, although many valuable contributions have been made to an understanding of the structures developed in such systems. Important papers have been published by Kurdjumow, Gridnew and co-workers, Obinata,18.'9 Greninger,20.21 and Others. The work to be described in this paper was an outgrowth of preliminary studies on the isothermal transformation of a entectoid aluminum bronze, after it became apparent that the alloy under study was reacting somewhat differently than the similar alloy used by Smith and Lindlief. Preliminary Experiments The material used in this study was a high purity aluminum bronze especially prepared by Ampco Metal, Inc. It analyzed: Copper—88.07 pet, Aluminum—11.89 pct, Iron-—0.02 pet, Manganese—-.OI pct, Others—Balance. Although some disagreement exists on the exact composition of the eutectoid, this alloy was believed to be of essentially eutectoid composition even though some pro-eutectoid* delta particles existed in the microstructure of furnace cooled specimens. Specimens transformed isothermally at temperatures slightly below the eutectoid showed relatively large amounts of pre-eutectoid delta, but as will be shown later, this results

Jan 1, 1949

By F. R. Archibald, C. M. Nicholson

The present paper may be considered complementary to an earlier contribution on the same subject by F. R. Archibald and C. F. Jackson.1 It is particularly concerned with engineering and technological aspects of the operations at the Harleyville Alumina Plant during its period of operation from January 1945 to July 1946. The plant was built for and operated by Ancor Corporation, at Harleyville, South Carolina, as part of the government sponsored wartime program related to alumina production from domestic raw materials. The main purpose of the program was to secure technical and engineering data, based on actual plant experience, that might serve as a foundation for large scale production of alumina from raw materials other than bauxite. The Harleyville plant was directed specifically to treatment of clays found in very extensive deposits in the Carolinas and Georgia using the lime-sinter process developed by Ancor Corporation. It is considered that the purpose stated above has been served and this paper is to record and discuss some of the more important findings. The main factor in location of the plant at Harleyville was the presence in that locality of a rather remarkable deposit of high calcium limestone. The clay mining operation was centered near Aiken, S. C., and although a rail haul of ninety miles was involved there were, at the time, factors favorable to the Harleyville location offsetting, in part, the cost of transportation of clay, There are, no doubt, locations in the general area where clay and limestone deposits may be found in closer proximity hut they had not been proven up when the project was undertaken. Availability of power from the Santee-Copper development whose high tension line skirted the Property; ready access to rail and highway transportation; the promise, realized in actuality, of ample supply of soft water; and availability of labor supply were other factors of importance. Moreover, the general area has the decided advantage, for this type of operation, of a mild climate. Construction was begun in August 1943, and although stopped for a time priding review of the general situation that fall, it was resumed, albeit with less urgency, and substantially completed by the end of 1944. The total capital cost was approximately $3,460,000 The first alumina was turned out in April 1945 and from then until the plant was closed down in July 1946, the operations followed a succession of periods of production alternating with periods in which minor alterations were made in conformity with experience. Steady improvement was made and at the time Operations were discontinued it was considered that experience and the necessary engineering were in shape for removal of the remaining bottlenecks and a somewhat major revision in one section of the plant. Unfortunately this could not be carried out and it was necessary to discontinue the

Jan 1, 1949

By W. R. Hibbard

Although extensive pole figure studies have been reported by Brick1 and others2,3 showing preferred orientations in rolled and annealed 70-30 alpha brass, and by Hermann and Sachs4 in 70-30 alpha brass cups, comparatively little information has been published on textures in drawn 70-30 alpha brass tubes. Crampton5 reported a (110) , [111] texture in drawn brass tubes based on selected individual X ray photograms following the method of Norton and Hiller,6 but the extent and ease of developing this texture and the annealing texture have not been reported and pole figures of these structures were not found in the literature. The present investigation was further stimulated by the possible influence of textures on the mercury stress-corrosion cracking of brass tubes. According to Snoek,7 iron-nickel alloy sheet with a strong cubic texture was more resistant to corrosion than a randomly oriented sheet. Crampton5 reported that single crystals of 70-30 alpha brass drawn into tubes did not crack after 24 hr in a standard mer-curous nitrate test. Edmunds12 found that single crystals of 70-30 alpha brass did not crack in a standard mercurous nitrate test but did crack when subjected to ammoniacal vapor. Wasserman11 reported a similar failure of a single crystal of brass in ammonia. A tube with a strong texture might approach single crystal behavior and tend to resist mercury cracking if the differences in orientation between adjacent grains were sufficiently slight. Preparation OF Specimens Crampton's5 tubes drawn 28 pct reduction in area developed a slight degree of preferred orientation while in tubes drawn 48 pct it was more marked. Based on this information, in order to obtain specimens with markedly different degrees of preferred orientation but with the same final draw, two sets of 70-30 alpha brass tubes were made following the mill schedules shown in Table I. The final draw involved a large reduction in outside diameter, and a ratio of reduction in area to reduction in outside diameter similar to that reported by Crampton,5, 10 to cause mercury cracking of brass tubes. The brass contained 71.31 pct copper, 0.01 pct lead, 0.01 pct iron and zinc by difference. Determination of Pole Figures A 6-in. length from each tube was rotated rapidly by an electric stirrer in 25 pct nitric acid until the gauge was reduced to 0.003-0.005 in. The tubes were carefully cut longitudinally and the walls gently flattened. They were further etched in 25 pet nitric acid to 0.0015 in. thickness and (111) pole figures were determined using copper K-alpha radiation in the manner described by Brick.' The three general types of pole figures

Jan 1, 1949

By F. L. Ruhlman, Max C. Eastman

The termination of the recent war marked a major changc in the oil-field operations at. Elk Hills. Production was greatly curtailed, various experimental production projects were started, and a long-range exploratory program was inaugurated. Production was reduced from the wartime peak of 65,000 bbl per day to the current rate of about 8ooo bbl per day in order to maintain an available source of crude that can be drawn upon during a national emergency. The existing production rate is deemed essential to carry on the experimental production projects. These projects are being conducted to determine the best methods and means of maintaining the Reserve, shut in, but in a state of readiness to produce the maximum quantity of oil in the most expeditious manner. Projects now being investigated include: (I) protection of surface equipmerit; (2) repair of wells that might damage the reservoir; (3) gas injection; (4) water eneroachment, (5) gravity drainage. An exploratory program is being carried on to determine the amount of recoverable oil in the unexplored portions of the Reserve. The Shallow-zone exploration is practically completed, but owing to the complexity of the Stevens structure and the magnitude of the oil discoveries in the Stevens, exploration will probably continue in that zone for another two years. Introduction Summary of Development History of Elk Hills Although a detailed history of Elk Hills oil field is presented in various publications,1,2 a summary of its unusual development and production history will be given in order that the present problems may be more readily understood. The first development that resulted in commercial production was in the central part of the Reserve. The first well, Hay No. I, in sec 36-R,* was completed in January I9I9, and was soon followed by 37 Others in the same general area. It is commonly referred to as the Hay-Carman area and was shut in in stages from 1925 to 1934 as a result of litigation regarding the title to the land. Not being highly producti,, only about 6½ million barrels of oil with a large volume of gas was produced from the area prior to the shutdown. Shortly after the start of the development of the Hay-Carman area, drilling was started 6 miles east in sec 36-S' Tupman NO. I came in for 5000 bbl per day early in I92o, It was followed by more than 200 others in the next few years, and the field became one of major importance. Produc-

Jan 1, 1949

Jan 1, 1949

By J. K. Edgar

For a number of years the production and use of super-purity aluminum (better than 99.99 pct) has been steadily increasing. High-grade lots of. such aluminum show certain outstanding characteristics not found in lower grades containing principally silicon, iron and copper as impurities. One such characteristic is the so-called "self annealing," that is, the re-crystallization of the heavily cold worked metal at room temperature.' Interest therefore is aroused as to the effects of the impurities. It is well known that the amounts of silicon and copper which occur in aluminum of better than 99.95 pct are completely soluble, at least at elevated temperatures (above 200°C). Iron, on the other hand, is known to be fairly insoluble in solid aluminum. Thus, a knowledge of the limits of this solubility would he of considerable use in studying the characteristics of the high purity metal. All investigators have agreed that iron has very low solubility in solid aluminum. Rosenhain, Archbutt and Hanson2 reported traces of an aluminum-iron phase in the "purest samples of aluminum obtainable." Gwyer and Phillips3 reported that an iron constituent was visible under the microscope in metal containing ".0088 per cent iron." Roth4 found that in the solid state the solubility of iron in high purity aluminum was 0.01, 0.01, 0.017 and 0.022 pct at 225, 320, 500 and 600°C respectively. Dix5 working with alloys containing less than 0.03 pct impurities, concluded from microscopic and chemical analyses of eutectic areas that the eutectic composition was close to 1.7 pct iron. Dix placed the eutectic temperature at 65s°C. Archer and Fink,6 using high purity aluminum-iron alloys, found that the hypoeutectic liquidus intersects the eutec-tic horizontal at 1.7 pct. This is in fair agreement with the investigation of the aluminum-iron system by Gwyer and Phillips who placed the eutectic at 1.89 pct iron with a freezing point of 653'C. Preparation and Chemical Analysis oP Alloys Electrolytically refined aluminum (99.991 pct aluminum) and a high purity alumi-num-iron alloy (11.45 Pet iron) were used in the preparation of the alloys for this investigation. To aid in controlling the iron content of the experimental alloys, an alloy of lower iron content was prepared first from these materials. The high purity aluminum was melted and heated to about 700°C in a plumbago crucible coated with alundum cement and the aluminum-iron alloy was then added. The alloy was thoroughly stirred, fluxed and skimmed and then chill-cast into notch bars. The aIlalyses of the three materials are given in Table I. The alloys for the determination of the solid solubility of iron in aluminum were prepared by melting 600 g total of the aluminum plus the required quantity of the aluminum-iron alloy (No. 92531). These

Jan 1, 1949

Jan 1, 1949

By definition the word "grout" means a thin mortar, or a kind of plaster or cement, and "grouting" means to fill up or finish with grout. The words "cement," "plaster" and "mortar" mean a substance that is used in a soft state which subsequently hardens. Thus, grouting is the filling of void space with a substance that hardens. Construction cements are the most common substances used, either by themselves or in mixtures, but the term grouting is applied quite correctly when other substances such as plastics and certain chemicals are used. Also, the use of the term grouting to cover the filling of voids with materials that do not actually become hard, such as the flotation tailings used in grouting in the southeast Missouri lead district, should be considered correct, as some stiffening does take place and, anyway, it is a better descriptive term than any substitute. Engineers are interested in grouting because some of the materials with which they must work contain voids, and certain conditions can be improved if these voids can be filled with something solid and permanent. Grouting is done to accomplish several purposes: I. To stop the passage of fluids and gases, 2. To cement materials together to make them stronger, and 3. To prevent consolidation of materials by filling void space with something solid as a replacement for the air and water that could be forced out under load. The construction industry uses grouting extensively for all three purposes. Grouting is used to stop water percolation under and around dams. It is used to control water flow in tunnel driving and in shaft sinking. It is used to improve foundation conditions under civil engineering structures by permanently filling void space and thereby reducing settlement, or by cementing broken rock together and increasing its supporting strength. The oil and gas industry does a lot of grouting, primarily to stop the passage of gases and fluids. The search for oil at increasingly greater depths has meant greater investment per well, and the oil industry has spent large sums on development of improved drilling methods. This

Jan 1, 1949

By David Turnbull, J. H. Hollomon, J. C. Fisher

Understanding of the diffusion problem has recently been furthered by the analysis of Birchenall and Meh1.l They pursued the problem of the variation of the diffusion coefficient with composition for non-ideal solid solutions. Their analysis follows the tradition of Wagner,l Jost, Dehlinger, and Darken & who assumed the net flux of diffusing material to be proportional to the gradient of a quantity related to free energy. The basic assumption in Birchenall and Mehl's formulation of the problem is that the net flux of diffusing material is proportional to a thermodynamic activity gradient. To estimate the applicability of the derived relations, they corrected the diffusion coefficients of carbon in austenite by utilizing Smith's6 activity data for carbon, and the diffusion coefficients for zinc in copper with activity data computed from the vapor pressure measurements of Har-greaves.' The corrected coefficients for carbon were virtually independent of carbon concentration. For the diffusion of zinc in copper a moderate variation of diffusion coefficient with concentration remained after the correction. The problem of diffusion can be formulated in another way than that used by Birchenall and Mehl. The method is that of chemical rate theory and has been used by Eyring and his coworkers8,9 as well as by Eyring and Zwolinskilo in a discussion to Birchenall and Mehl's paper. As yet the method has not been applied to substitu-tional solid solutions. On the basis of their assumptions, Eyring and Zwolinski derived a relation between the diffusion coefficient and activity that is identical with that of Dehlinger and Darken but which does not correct for the variation of the diffusion coefficient with concentration as well as does the relation derived by Birchenall and Mehl. It was thought that the theory of diffusion would be more complete if the inconsistency between the two analyses could be rationalized and if diffusion in substitu-tional alloys were analyzed on the basis of the concepts of the chemical rate theory. Chemical Rate Theory According to the theory of absolute reaction ratess the reaction +..... +X, Eq I is viewed as taking place in two steps. First the reactants A1, A², . . . A; combine to form an activated complex M with which they are in equilibrium: A1 + A1+ . . . + A=M. Eq 2 Second the activated complex decomposes to give the products XI, XZ, . . . Xi: M?X, + X²+ . . . +Xi Eq g It has been showns that the number of activated complexes decomposing per unit volume per unit time is given by the expressiont kT -h CM † The transmission coefficient has been taken as unity.

Jan 1, 1949

By Harry Gard Knox, F. R. Harris

This paper covers some of the problems presented to the oil industry in the drilling of oil wells in the open waters of the Gulf of Mexico. The hazards, delays and relative costs of offshore drilling are reviewed and various forms of drilling platforms discussed. The requirements of the offshore drilling rig are summarized together with the principal items affecting the cost of construction. Sea waves and their size and characteristics as affecting offshore platforms are reviewed. Drilling platforms are classified as fixed, or fixed and floating. Fixed platforms of the conventional cofferdam and pile-supported type are discussed together with their good points and their limitations. The desirability is pointed out of eliminating as much offshore work as possible where operations are subjected to constant and expensive delay and substituting therefor the prefabrication of structures ashore or in sheltered waters. Marked economy will come with the standardization of offshore rigs aid special means of transporting them to the site. Several types of structure which are partly pile-supported and partly buoyancy-supported are discussed and their possibilities of future usefulness commented upon. General Considerations The predominant attribute of offshore drilling equipment is that it must be equal to the job in hand. We therefore give first thought to the matter of adequacy. In view of the probable depth of drilling, the investment involved and the per diem labor costs, it is assumed heavy modern drilling equipment will be employed. In order to usc such equipment efficiently, the working deck must be ample in size and strength and supported so as to be relatively free from motion and from green seas even in heavy storms. These requirements necessitate a high and rigid land-based support for the drilling rig and machinery with plenty of space for supplies, such as pipe, mud, water and fuel, with reserves for days when transportation from shore is impracticable. In offshore rigs the crew will be housed onboard in comfortable quarters, probably air conditioned and equipped with a galley and refrigerated food storage. An important consideration will be the ability to transfer stores and crew to and from the rig in all but the heaviest weather and the platforms must be protected from the impact of supply vessels when alongside. It will be essential to maintain continuous communication with shore by radio or cable, not forgetting the possibility of a helicopter landing space for the transfer of crew and light stores as well as a means of general communication. Whatever structure is constructed must be secure from storms of hurricane force and a safe place for the operating crew to work. If the well comes in, the drilling rig will presumably be removed and a small but rugged pile-supported platform will remain to carry the Christmas tree with safe working space around it. It will be protected from damage on all sides by buffer piles or dolphins. It is assumed that the flowing oil will be piped to storage tanks in the vicinity of the well. An individual tank for each well or a

Jan 1, 1949