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By A. E. Gorum, J. Washburn, E. R. Parker

Experimental evidence was obtained in support of the idea that cleavage fracture can be initiated by dislocation pile-up. The high ductility of MgO crystals when tested in bending comPared to their relative brittleness in tension was explained on the basis that large pile-ups are more likely in a tension specimen. CLEAVAGE fractures have been a problem of major concern for many years. A number of large steel structures have failed in a brittle manner, usually suddenly and without warning; often the failures occurred for no obvious reason and at nominal stress levels well within the generally accepted range. A great deal of data have been collected about factors that contribute to failures,1 but the physics of the fracture process has never been revealed. cottrel12 has recently developed a theory of brittle fracture in ductile materials which was based upon the concept that dislocations moving on two intersecting planes can unite to form a crack nucleus. This theory accounts for the known effect of grain size and for the effect of testing temperature. There has, as yet, been no experimental evidence published that would substantiate this or the earlier theories based on stress concentrations due to piled-up dislocations. The study reported herein was conducted to obtain information that would either substantiate or disprove the

Jan 1, 1960

By George Cole

WHILE many parts of Canada's pre-Cambrian shield are well served by railway, it is frequently necessary for prospecting purposes to proceed farther into areas in-accessible by rail. To such areas in summer the canoe was at one time the accepted means of travel for the prospector while the dog team was much used in winter. Al-though summer travel was much improved by the development of the outboard motor, the lack of facilities for cheap transporta-tion has been a serious hindrance to the employment of capital in opening up the distant fields. The pre-Cambrian surface of Manitoba, like that of Ontario, is hummocky, with rounded hills and ridges of rock alternating with basinlike depressions and valleys oc-cupied by lakes and rivers or by many low-lying portions covered with muskeg. Routes to the mines have not usually been direct or easy and seasonal vagaries have presented problems in themselves. In summer, water transportation may be the cheapest method for the longer dis-tances but it is not every water route that will satisfy the conditions of loading freight onto a boat or scow and of conveying it without interruption to its destination. By its location, a mine may require a large program of boat transportation in summer over part of its route, to be followed by winter freighting for the remainder. In order to carry on development and produc-

Jan 1, 1940

By William D. Klopp

A study was conducted of the tensile and creep properties of are-melted and electron-beam-melted tungsten over the temperature range 2250° to 4140°F. The tensile and creep strengths vary with pain size, the finer -grained materials being stronger. The activation energy for transient creep at 2250° to 3500°F is 95,000 cal per (g)(mole), while that for steady creep at 3300o to 4000°F is 141,000 cal per (g)(mole). At 2875o to 3300°F the apparent activation energy for steady creep decreased with decreasing temperature. It is suggested that cross slip is rate controlling during transient creep, while dislocation climb is rate controlling during steady creep above 3300° F. ALTHOUGH considerable data have been generated on the high-temperature tensile properties of powder-metallurgy tungsten,1 relative few data have been published on the properties of are-melted2 or electron-beam melted tungsten.3 Furthermore, the available data show a fairly large amount of scatter at high temperatures. The effects of structure and purity have not yet been defined, aside from observations that high-purity electron-beam (EB)-melted tungsten3 and single-crystal-plasma-flame tungsten4 are weaker than less pure powder-metallurgy tungsten. The creep behavior of powder-metallurgy tungsten has been studied, but no data are available on the creep behavior of tungsten consolidated by melting. Green5 found that powder-metallurgy tungsten exhibited linear creep at 4082° to 5072°F with an activation energy of 160,000 cal per (g) (mole). The similarity of this activation energy to that of 153,000 cal per (g)(mole) for volume self-diffusion6 suggests that recovery of strain hardening by dislocation climb is rate controlling in this temperature range. In studies at 4800°F, Sutherland and Klopp7 concluded that grain size significantly affected the creep behavior of commercial powder-metallurgy materials. This grain-size effect was suggested by sherby,8 although the opposite relation had been reported for aluminum.' The purpose of the present study was twofold: first, to provide baseline data on high-temperature tensile and creep properties of are-melted and EB-melted tungsten for concurrent tungsten alloy studies, and, second, to determine the phenomenolo-gical effects of structural and purity variables on the high - temperature mechanical properties of tungsten. EXPERIMENTAL The are-melted tungsten materials were prepared by melting sintered 1-1/4-in.-diam electrodes into 2-1/2-in.-diam by 5-in.-long ingots. The are-melting facility has been described previously.' Eight ingots were melted, machined, and hot-extruded at

Jan 1, 1965

By Arthur C. Simmons

The area that produces Pennsylvania grade, which includes New York, Pennsylvania, West Virginia and a part of Ohio, increased its production in 1942 about 1,580,000 bbl. over that attained in 1941. Such an increase is substantial for this area, and measured in terms of increased output of lubricants, for which the crude is particularly suitable, it represents a needed arid worth-while addition to the lubricant resources of the United States. The year 1942 was a difficult operating period for most of the petroleum-producing areas in the United States, but the Appalachian region, owing principally to its location, type of operations, and crude value, suffered less from war influences than other areas. The state of Pennsylvania produced 17,823,870 bbl. of crude oil, which is approximately 63 per cent of the total production of Pennsylvania grade in the entire area. Production Bradford Field The Bradford field, which produces almost wholly by water-flooding methods, increased its production nearly 4000 bbl. per day over 1941 despite a very slight reduction in total number of wells completed. Well completions in the Bradford field (in both New York and Pennsylvania) includc both producing oil wells and water-intake wells. About half of the well completions are producing oil wells and the remaining half are water-intake or injection wells. About 10 per cent of the total well completions of the Bradford field were in Cattaraugus County, New York. No segregation of well completions is available, so that precise statistics cannot be given for New York and Pennsylvania.

Jan 1, 1943

By Arthur C. Simmons

The area that produces Pennsylvania grade, which includes New York, Pennsylvania, West Virginia and a part of Ohio, increased its production in 1942 about 1,580,000 bbl. over that attained in 1941. Such an increase is substantial for this area, and measured in terms of increased output of lubricants, for which the crude is particularly suitable, it represents a needed arid worth-while addition to the lubricant resources of the United States. The year 1942 was a difficult operating period for most of the petroleum-producing areas in the United States, but the Appalachian region, owing principally to its location, type of operations, and crude value, suffered less from war influences than other areas. The state of Pennsylvania produced 17,823,870 bbl. of crude oil, which is approximately 63 per cent of the total production of Pennsylvania grade in the entire area. Production Bradford Field The Bradford field, which produces almost wholly by water-flooding methods, increased its production nearly 4000 bbl. per day over 1941 despite a very slight reduction in total number of wells completed. Well completions in the Bradford field (in both New York and Pennsylvania) includc both producing oil wells and water-intake wells. About half of the well completions are producing oil wells and the remaining half are water-intake or injection wells. About 10 per cent of the total well completions of the Bradford field were in Cattaraugus County, New York. No segregation of well completions is available, so that precise statistics cannot be given for New York and Pennsylvania.

Jan 1, 1943

By L. P. Teas

Although 1927 in the Arkansas-Louisiana territory will probably pass into history as a year of small profits and little new production, nevcrtheless during this period two large gas fields were developed; two new oil fields were discovered, and two new oil horizons, hitherto of minor annual production Fig. 1.—Production of North louisiana and ARkansas by fields, for 1926 and 1927. (Upper blocks represent 1926 production; lower blocks, 1927 production ) importance, were developed. In spite of the "hard times" some of the leading supply houses did more business this year in this district than in any year since 1920.

Jan 1, 1928

By M. B. Riordan

A surface indicating pressure, temperature and flow instrument that ernploys variable frequency sensing elements has proved useful in evaluating flow characteristics of wells. Relative productivity of individual oil and gas sands in a given well can be analyzed at several back pressures. The variable frequency sensing elements are an improvement in sensitivity and accuracy and make possible observation of temperature and pressure variations that have not been possible heretofore. The surface indicating featuere results in a more direct approach to solving problems and eliniinate; many assumptions. All three subsurface factors are evaluated, and correlation between them results in a direct means of analyzing reservoir. and well conditions. Surveys have been used to evaluate well performance. locate gas entry In high ratio wells and to investigate gas injection and water flooding conditions. INTRODUCTION In a flowing well that is open to a multiple number of producing sands with varying characteristics. it is valuable to know which sands are producing fluid at a given back pressure and in what relative quantity. Core studies could qualify an interval as productive, and reserves would be computed on this basis. Unless the well is produced so that the interval does contribute. irreparable damage to the interval can occur. It is generally accepted that the optimum condition of pro-

Jan 1, 1951

By M. B. Riordan

A surface indicating pressure, temperature and flow instrument that ernploys variable frequency sensing elements has proved useful in evaluating flow characteristics of wells. Relative productivity of individual oil and gas sands in a given well can be analyzed at several back pressures. The variable frequency sensing elements are an improvement in sensitivity and accuracy and make possible observation of temperature and pressure variations that have not been possible heretofore. The surface indicating featuere results in a more direct approach to solving problems and eliniinate; many assumptions. All three subsurface factors are evaluated, and correlation between them results in a direct means of analyzing reservoir. and well conditions. Surveys have been used to evaluate well performance. locate gas entry In high ratio wells and to investigate gas injection and water flooding conditions. INTRODUCTION In a flowing well that is open to a multiple number of producing sands with varying characteristics. it is valuable to know which sands are producing fluid at a given back pressure and in what relative quantity. Core studies could qualify an interval as productive, and reserves would be computed on this basis. Unless the well is produced so that the interval does contribute. irreparable damage to the interval can occur. It is generally accepted that the optimum condition of pro-

Jan 1, 1951

By R. E. Old

THROUGH the use of pressure and production records, formation properties and bottom-hole sample data, the performance of an oil reservoir may be studied analytically to define and evaluate the natural forces acting on and within the reservoir. Use is made of material-balance methods and the equations for natural water encroachment to estimate reserves. Methods for calculation of pressures are given. A study of the Jones sand, Schuler field, Arkansas, has been made and is given here to illustrate the value of the methods discussed.

Jan 1, 1942

By Robert H. Palmer

Sacuranao Field.—Bacuranao field is about 12 miles east of Havana, along the contact between Cretaceous sediments and a serpentine intrusion. The zone lies within an extensive anticlinorium. The field had no developments during the year 1939. The production of 9½ bbl. per day is distilled and the gasoline and kerosene are extracted. The asphalt residue. is sold for road construction. The gas is compressed and

Jan 1, 1940

By Robert H. Palmer

Sacuranao Field.—Bacuranao field is about 12 miles east of Havana, along the contact between Cretaceous sediments and a serpentine intrusion. The zone lies within an extensive anticlinorium. The field had no developments during the year 1939. The production of 9½ bbl. per day is distilled and the gasoline and kerosene are extracted. The asphalt residue. is sold for road construction. The gas is compressed and

Jan 1, 1940

By T. F. Witherbee

AS the forms of blown-out furnaces are of much interest to ironmasters and metallurgists, the manner of taking the accompanying sections of the Cedar Point stack is here given. The diagrams show the original and also the final shape of the furnace after a two years and twelve days' blast,, during which the following solid materials passed through it, viz.: Coal, 41,000 tons; ore, 57,000 tons; limestone, 30,000; total, 125,000 gross tons. Product, 411/4 tons per day Bessemer pig iron. The apparatus used in taking the sections was a modification of that proposed by Mr. Frank Firmstone,* and consisted of a sliding rule, to follow around the circumference of the stack, which rule was connected by a string to a segment of a circle of 24 inches radius. The segment was carried by an arm which connected it to a huh as a centre, 2 inches in diameter. A second string was wound around the hub, and communicated motion to a pencil-carrier, the pencil of which marked out on paper the exact outline, and reduced it to a scale of & inch to the foot. The whole machine was made in about three hours, with the facilities of a carpenter's shop, and gave in operation every irregularity of the lining. The sections were taken at salient points, by lowering a hanging staging on which the apparatus was placed. Tracings from the paper of the machine were made, and, as in this case several copies were required, the tracings were glued on to thin sheets of basswood, and patterns carefully sawed out with a bracket saw.

Jan 1, 1879

By R. B. Sudderth, C. R. Merigold

Greater, emphasis is being placed on recovering nickel from laterite ores by ammonia leaching techniques. New methods are required for lower cost, non-polluting techniques to separate more efficiently the metals of interest. Liquid ion exchange techniques meet these requirements with the added advantage of producing salable electrowon nickel cathodes at the plantsite. A complete solvent extraction- electrowinning process is described, including preliminary engineering and cost data for a typical plant producing 50 million pounds of nickel per year.

Jan 1, 1973

By P. L. Hofmann

The National Waste Terminal Storage (NWTS) Program was established in 1976. The objective of this program is to develop the technology and provide the facilities for the safe, environmentally acceptable isolation of civilian- and defense-related, high-level and transuranic nuclear wastes, including spent fuel elements, for which the federal government is responsible. The principal emphasis of this program is on disposal in mined geologic repositories. Technology development in support of the NWST program includes the formulation and management of a strong basic science and engineering program to generate an appropriate data base to aid in understanding of the key geological processes and major engineering structures involved. The current status, problems, and future plans of the technology program will be summarized.

Jan 1, 1984

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who called at Institute headquarters during the period Feb. 10, 1916 to Mar. 10, 1916: D. A. S. Bell, Ottawa, Can. E. B. Latham, Santa Maria, Cal.. John Cooper, Exeter, Devonshire, Eng. H. N. Lawrie, Portland, Ore. I. Dally, Seattle, `Wash. L. A. Levensaler, Tacoma, Wash. George W. Evans, Seattle, Wash. George J. Lyon, Schenectady N. Y. Alexander Fyfe, London, Eng. Fred MacCoy, Antofagasta, Chile. F. C. Greene, Seattle, «rash. J. Mitchell-Roberts, London, Eng. I. Ishikawa, Tokio, Japan. Chas. W. A. Sultan, Yonkers, N. Y. William Kelly, Vulcan, Mich. R. B. Tinsley, Big Stone Gap, Va. Paul S. King, Wilmington, Del. Walter E. Trent, Reno Nev. Oscar Lachmund, Greenwood, B. C. Alfred W. G. Wilson, Ottawa, Can. J. S. Lane, New York City. Nelson Dickerman has resigned as general Manager of the Pato Mines (Colombia), Ltd., and The Nechi Mines (Colombia), Ltd., and will return from Colombia to San Francisco, Cal., the latter part of April. W. A. Prichard has been appointed as his successor.

Jan 4, 1916

By G. Van Esbroeck

THE copper mines of the Katanga region in the Belgian Congo lie along the same mineralized belt as those of Northern Rhodesia. There are two distinct types of deposits in that belt, the dolomitic and the quartzitic. In the dolomitic type the metallic minerals are found in a dolomitic limestone country rock. Through oxidation and enrichment, large deposits of high-grade oxidized copper ores were formed, some of which are being worked by the Union Miniere du Haut Katanga. Such deposits are all in Katanga. The quartzitic deposits are found in Katanga and Northern Rhodesia. Here the primary mineralization occurred in sandstones and quartzites, in horizons stratigraphically lower than the dolomites. These rocks are not favorable to secondary enrichment and the oxidized zone is poorer than the sulphide zone, which alone contains the ore. There are also in Katanga a few ore-bearing veins. One of them is being worked in the Prince Leopold mine at Kipushi.

Jan 1, 1939

By David B. Reger

Extensive drilling for gas and increased pipe-line building were the major petroleum activities in West Virginia during 1937. According to the West Virginia Department of Mines, 1034 permits to drill were issued. A running account of operations from trade journals and other reports shows that 1041 wells were drilled, resulting in 193 oil wells with 1238 bbl. of daily production; 680 gas wells with 1,048,057,000 cu. ft. of daily open flow; and 168 dry holes. The new oil-well average is 6.4 bbl. per well per day; the gas-well average is 1,541,260 cu. ft. per well per day; the ratio of dry holes to completions is 16.13 per cent. Very little attempt was made to develop new supplies of oil. Because of the continued low price, operators evidently considered it good business to leave oil in the ground rather than to produce it at a loss or on a small profit basis. The principal oil wells completed, by counties, are: Calhoun, 16; Clay, 10; Pleasants, 17; Ritchie, 42; Roane, 16; Tyler, 13; Wetzel, 11; Wirt, 14; Wood, 13. The leading counties in gas, with the number of successful wells in each, are: Boone, 54; Braxton, 31; Cabell, 48; Calhoun, 46; Gilmer, 82; Kanawha, 134; Lincoln, 44; Ritchie, 56; and Wayne, 26. General State of the Industry In Table 1 will be found an approximate summary of oil and gas territory and reserves, oil and gas production and number of oil and gas wells. The amount of land under lease is an approximation, because the exact figures are not available through any public or private agency. The proved land and reserves represent the opinion of the writer. The oil production for 1937 is subject to revision, and the gas production for the same year is only an estimate, based on demand and supply. The number of oil and gas wells now active is also an approximation, based on previous studies, and revised for completions and abandonments. Principal, Areas of Activity In Boone County, 62 wells were drilled in various localities, resulting in 4 oil wells and 54 gas wells with 18,170,000 cu. ft. of new production.

Jan 1, 1938

By F. E. Calkins

THE following presentation of the more important accumulated facts and probabilities involved in copper ore deposition is based on my experience in examination work and study of the extensive litera-ture of the subject; to make personal mention of all sources of information would require the naming of a small army of able geologists and other investigators who have contributed to, building up the science. I have tried to present the salient features of the subject in logical order and condensed form, and to point out the relative importance of processes involved. Doubt-less many geologists could suggest some changes and many additions. ORIGINAL SOURCE The original source of all copper was in the earth's interior; it has been brought to the outer part of the earth, within reach of man, in three ways: (1) By intrusions and flows of basic igneous rocks containing copper in minute quantities, presumably as silicate or sulfide. No orebodies have been formed by this method. (2) As segregations within intrusive igneous rocks, the copper minerals having solidified at the same time as the rock itself. The few deposits known to have been formed in this manner have been of little or no importance. The oft quoted Sudbury nickel-copper deposits are now known to belong to the class following. (3) By gaseous or liquid aqueous emanations from ,large deep-seated masses of intrusive molten rock. These emanations, or mineral solutions, ascended through zones of connected openings in the earth's crust and dropped their load at points far above their source. Deposits formed in this manner were the primary source of nearly all, if not all, of the world's copper production.

Jan 10, 1923

By R. B. Schluter, M. M. Fine

Development of a process for winning copper from pelletized chalcocite concentrate is underway at the Bureau of Mines, Twin Cities Metallurgy Research Center. The new route from concentrate to metal by which the Bureau seeks to eliminate matte smelting and converting includes a two-stage fluid bed treatment. In the first stage, pelletized concentrate containing 32%Cu and 7% S is first desulfurized to less than 1.0% S in an oxidizing atmosphere. In the second stage, the calcine is metallized by reduction with hydrogen. Thereafter, the reduced product plus 10% CaO is routed to a smelting furnace which separates metallic copper from the gangue. Recovery and Cu content at this point are in the 97-98% range. This product must be refined to remove sulfur and iron so the metal is suitable for making wirebar copper. An important feature of the process is fine concentrate pelletization prior to fluid-bed treatment. This permits a shorter reaction time, a decrease in dusting and easier subsequent processing. In a broad sense, sulfide copper pyrometallurgy is a batch sequence in three separate vessels, i.e., a reverberatory furnace to yield matte copper, a converter to produce blister copper and another reverberatory furnace to produce fire-refined copper. Matte-smelting has remained relatively unchanged since it became a universal practice some 50 to 60 years ago. It is now serving a wide range of smelter feed materials, but many concentrates are not immediately amenable to the process. There are abundant copper resources which lack sufficient sulfur and other elements lo sustain the full chemistry involved in matte-smelting. This necessitates adding sulfur to make the product fit the process, and usually none of the sulfur is recovered. From the standpoint of pollution alone, the development of a smelting technique for low-sulfur concentrates not requiring the addition of sulfur would be a significant gain.

Jan 1, 1970

By A. W. Ashbrook

There are many methods of analysis available for compounds similar to those used in solvent extraction processes. However, the majority of these methods are not directly applicable to the determination of solvent extraction reagents, especially in raffinates. The number which are applicable is further reduced if limited to the more simple methods suitable for process control purposes. Commercial extractants are complex mixtures. The complexity is increased by the addition of diluents and modifiers in two-phase systems containing metals. Raffinates from solvent extraction processes contain the more polar components of the extractants and the products of decomposition. Only a limited amount of information is provided by total organic carbon or spectrophotometric analysis. The complexities of the systems require a combination of methods.

Jan 1, 1978