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By R. H. Johnson

All strata not yielding oil or gas in commereial quantities or a corresponding amount of water may be called dry in a wide sense. In petroleum geology, however, we may exclude all sands of too low or fine porosity to yield gaseous or fluid contents to the hole drilled in the sand before any original pressure that its contents may be under is disturbed. Most rocks are of this class and they are not reservoirs in our definition; their "dryness" is wholly a matter of course. What are the contents of the pores or what is the exact porosity of such rocks is of almost no concern to us, for economically they are "dry." What does interest us is the content of a rock having sufficient porosity and the pores of sufficient size to yield oil or gas in commercial quantities, if they were present under original pressure. Dryness of these reservoirs is a matter of supreme practical importance. Three views current as to such dryness seem, to me, to apply in a few cases only. It is the purpose of this paper to give reasons for this position and for believing that, in ordinary sedimentary rocks, there is only rarely a reservoir of competent porosity and undisturbed pressure that is dry in the sense of not yielding water, oil, or gas when first penetrated. 1. Gardnerl writes of some Kentucky sands, "There has never been present any salt water or other water in the sand." Absence of water cannot demonstrate this position. It is necessary to show that the rocks were not laid down in water, but in air, and that they became so enclosed, while still above the water-table of the ground water, that water has not been able to enter since. Most of these sands, and certainly the productive limestones, were deposited in water; and such sands as have been commercially productive show no reason for believing that the overlying shale or limestone was not laid down progressively from one direction and in water that would have flooded it. NO adequate explanation has been offered for this hypothesis, which is so inherently improbable. 2, Reeves2 urges that "sands originally water filled may have been drained of their water and not filled when later covered." It is difficult I James H. Gardner: Kentucky as an Oil State. Science, N. S. (1917) 46, 279-280. Reeves: Origin of the Natural Brines of Oil Fields. Johns Hopkins Univ. Circ., N. S. (1917) N. 3; Absence of Water in Certain Sandstones of the Appalachian Field. Econ. Geol. (1917) la, 354-378.

Jan 1, 1921

By W. F. Rochow, W. C. Burke

Numerous designs of linings and accessories, including dams, lifters, and heat exchangers, contribute greatly to kiln efficiencies. Greater conductivity is achieved with basic brick than with fireclay and high-alumina refractories, depending largely upon the use of steel plates in radial joints between adjacent brick to increase heat transfer through the lining. Refractory lifters expose all portions of the load to radiant or convective heat and raise some portions to higher temperatures by cascading the load down through the path of the hot gases. AMONG the many factors involved in rotary kiln efficiency, advantageous use of refractories is of major importance. So far as kiln lining alone is concerned durability is most significant, as shutdowns for repairs are costly in fuel consumption and production losses. Aside from selection of refractories best suited to the widely varying conditions under which rotary kilns are operated, lining design and accessory constructions within the kiln are highly important. The refractory most economical for any combination of operating conditions can be selected from a wide range of alumina-silica and basic refractories, including insulating, castable, and plastic fire bricks. In several cases silica brick can be used to advantage. Alumina contents of alumina-silica refractories range from 35 to 90 pct in increments of 5 to 10 pct. In general, bricks of relatively low alumina content are best for abrasion resistance, an important property for the brick used in chain sections of cement kilns or in feed end sections of limestone kilns. High-duty fireclay bricks of approximately 40 pct alumina and 55 pct silica are used to line the intermediate zones. Super-duty fireclay brick at slightly higher cost is warranted in operation of kilns with high intermediate zone temperatures and severe spalling conditions. Alumina-silica refractories with an alumina content of 50 pct and higher, termed high-alumina brick, are available in commercial classes of 50, 60, 70, 80, 85, and 90 pct alumina content. These refractories are generally used as high temperature zone linings or placed adjacent to the basic brick-lined sections when the treatment they are required to withstand is excessively severe. Use of basic refractories is confined mainly to zones of maximum temperature and most severe chemical action. Basic refractories ordinarily employed for high temperature zone linings of many rotary kilns comprise the classes shown in Table I. Each class is peculiarly well suited to various particular combinations of working conditions. The approximate chemical analyses of these classes also illustrate differences in compositions with respect to the major components.

Jan 1, 1956

By James A. Crookston, William D. Fitzpatrick

Committee C-8 of the American Society for Testing and Materials defines "Refractories" as "Material, usually nonmetallic, used to withstand high temperature," and it defines the term "Refractoriness" thus, "In refractories the capability of maintaining the desired degree of chemical and physical identity at high temperatures and in the environment and conditions of use." The ability to withstand high temperatures is critical to classifying a material as a "refractory." However, as the foregoing definition of "refractoriness" implies, the refractory material may be subjected to and is expected to resist not only high temperatures but a variety of other destructive forces incident to its use. These include abrasion, impact, thermal shock, chemical attack, and high level loads at high temperatures. The various industrial applications of refractories represent an infinite variety of combinations and degrees of severity of these destructive forces, including high temperatures. Naturally, such a variety of application conditions leads to a need for a wide variety of refractory products to satisfy those conditions. The number of refractory products available is great enough that some form of classification is necessary to a discussion of refractories. Refractories may be classified in several ways, but the most suitable one is based on their general compositions and to lesser degrees on their physical condition and distinctive properties. The primary types of brick include aluminosilicate brick (fire clay and alumina), basic brick (magnesia and chrome ore, alone and in various combinations), silica brick, insulating brick, and special refractories (carbon, Sic, ZrO,, zircon, borides, and nitrides). Brick are, of course, preformed and are usually heat treated at high temperatures before use, but are in some instances unburned and/or chemically bonded, including the relatively new class of tar-bonded magnesia and/or dolomite brick. In addition to preformed refractories, another broad category includes the so-called specialty refractories, which are usually made in the same types as itemized for brick-bonding mortars and high temperature cements, hydraulic setting castables or refractory concrete, plastic firebrick, and ramming mixes. Refractory grains, such as fire clay and high alumina calcines, dead-burned magnesite and periclase, and dead-burned dolomite are also considered refractory products. Brick are also classified on the basis of physical dimensions, as standard sizes and special shapes. The standard sizes are those which are of definite shape and design and are designated as 9 x 4 ½ x 2 ½ in. and 9 x 4 ½ x 3 in. straights and series. All other brick of non- standard sizes are referred to as special shapes. These come about as a result of a particular need for a given furnace or for a particular application.

Jan 1, 1975

The Keweenaw Peninsula in the Upper Peninsula of Michigan is plagued with abandoned prospectors' test pits and mine shafts, the result of exploration and operation of mines for over 100 years. The Fort Wilkins State Park in Keweenaw County alone has three open prospectors' pits within its boundaries, protected by wooden fences and maintained by the (Michigan State Conservation Department as a tourist attraction.

Jan 1, 1967

By Eugene S. Perry

The oil and gas industries in Montana continued through the year of 1937 with but little change. No new fields were discovered, and production of old fields did not vary greatly. No outstanding wildcat wells were drilled. Perhaps most notable were extensions in the western part of the Kevin-Sunburst field. Acid treatment of wells in the Kevin and Pondera fields continued with gratifying results.

Jan 1, 1938

By R. E. Stewart

The major mining companies of the world all face the problems associated with investing in new mining ventures. In particular, investment in foreign countries - whether these are advanced or developing countries - requires careful consideration. A thorough analysis of all the possible risks must be undertaken, so that realistic decisions can be made. Some of the points to be considered are outlined in this paper.

Jan 1, 1977

By R. K. Dunham, A. N. Styler

The results of two studies into the effects of undermining offshore room and pillar workings by longwall faces are presented. The first study indicated no potential instability from undermining one level of room and pillar workings. On the basis of this it was decided to undermine two levels of room and pillar workings, again monitoring pillar stability. The results showed no signs of increased instability.

Jan 1, 1982

By Swapan Bhattacharya

United States federal and state regulatory authorities require underground mine operators to adopt adequate measures to minimize material damage to the surface caused by mine subsidence. This paper presents an approach to define and determine the extent of material damage due to subsidence from underground coal mining. The basic steps involved in the development of adequate criteria have been enumerated together with the approaches and methodologies used.

Jan 1, 1984

By E. J. Rapperport, C. S. Hartley

I TTRIUM is a close-packed-hexagonal metal with a c/a ratio of 1.5712.1 This low c/a value prompted a cursory examination of the deformation modes to obtain more data on the deformation characteristics of hcp metals with subideal c/a ratios. The chemical analysis of the arc-melted stock from which the specimen was cut is given below in Table I.

Jan 1, 1960

By J. A. Corbyn

An analysts of mining investment from the point of view of financial optimization is presented. The method uses differential equations to describe financial performance rather than the more usual method of modeling mine accounts from year to year. The analysis shows there is a optimum mine life that can be easily determined if certain simplifications are made. Tables are given to facilitate computation of the optimum life.

Jan 1, 1985

A remarkable industrial renaissance is underway in the People's Republic of China (PRC), says USBM's Dr. K. P. Wang in his recently released 96-page report on "The People's Republic of China-A New Industrial Power with a Strong Mineral Base." Dr. Wang's summary of the current mineral position of the PRC includes many insights into its future potential and trade possibilities with the West.

Jan 2, 1976

By William Y. Holland, Roger H. Cook

In view of the increasingly widespread deterioration of concrete structures as the result of the interaction of the alkalies sodium and potassium released by hydration of portland cement and susceptible rocks and minerals in aggregates, it is believed that a paper summarizing the geographic distribution of these aggregates will be of interest to producers and users of concrete, concrete products, and concrete-making materials.

Jan 10, 1953

By Samuel H. Dolbear

THE value of a mine is basically dependent on its capacity to yield profits. Since the ore must be mined, treated, and sold, some of it in various future years, there is a risk involved as to future costs, selling price, and working conditions. It cannot be expected that the economic condition existing at the time of valuation will continue unchanged for long periods in the future.

Jan 9, 1953

By F. O. Blackwell

It is roughly estimated that some three hundred companies in the United States engaged in mining and the kindred arts now employ electricity in their operations. As all these plants have been installed within the last few years, it is evident that mining engineers have been quick to appreciate the great advantages of the use of electricity and adopt it for their many requirements. In

Jan 1, 1894

By C. A. Allen

For over three years we have been endeavoring to reduce the number of fatalitics and minor accidents in Utah. The physical condition of the FIG: 1.—Number kiLlEd per million short tons of coal produced in ColoraI)o, New Mexico, utah, Wyoming, and bituminous mines of the United States 1014 to 1920. mines, concentrators, and smelters is good, yet the number of accidents,

Jan 1, 1923

By C. A. Allen

For over three years we have been endeavoring to reduce the number of fatalitics and minor accidents in Utah. The physical condition of the FIG: 1.—Number kiLlEd per million short tons of coal produced in ColoraI)o, New Mexico, utah, Wyoming, and bituminous mines of the United States 1014 to 1920. mines, concentrators, and smelters is good, yet the number of accidents,

Jan 1, 1923

By George Newton

When Mr. Bailey asked us to present a paper describing our new BOF shop, he requested that we avoid a presentation heavily laden with detail and statistics. Not only have we attempted to do this, but also we have prepared a number of colour slides which, hopefully, will provide you with a graphic conception of the facility. The installation of the BOF facility at the Steel Co. of Canada's Hilton Works was delayed many years because of the remarkable production growth of the oxygen open hearth furnaces in No. 3 shop. However, in mid-1960 it became strongly evident that not only would increased ingot capacity be required, but also that N0.2 shop - with vintage non-oxygen open hearth furnaces - would have to clean its stacks in the near future, or be closed down. A decision to embark on the BOF facility was made in 1967 after an extended period of in-depth planning and assessment of industry trends.

Jan 1, 1972

By J. B. Cohen, M. B. Beaver, R. J. Black

RECENT investigations have shown that face-centered cubic metals may deform by twinning. Blewitt, et al' found that at 4.2"K the mode of def~rmation of single crystals of copper changed at large strains and markings formed on (111) planes. Later they- emonstrated by X-ray diffraction and metallography that the markings were twins and showed that favorably oriented single crystals of copper deformed by twinning at 78°K. They also observed twinning in silver and gold deformed at 4.2 and 78°K. Wagner3 obtained evidence for twinning from the peak shape of diffraction lines of silver cold-worked at 78°K, but twins small enough to cause such effects are not likely to be detected metal-lographically. In the work reported here lamellar structures were observed in deformed silver-gold alloys. They appeared to be mechanical twins, but metallography could not establish this conclusively. Their tendency to form depended on strain rate, temperature and composition. Specimens of silver-gold alloys (0 to 83 wt pct Au) were deformed plastically. One set was worked by hammering under liquid nitrogen, at room temperature and at intermediate temperatures. Another set was compressed slowly in liquid nitrogen to the same reductions as those produced by hammering. Tensile specimens (0.015 x 0.120 x 1.5 in.) of various compositions and approximately equal grain size (0.011 to 0.016 cm) were tested at -195°C and at room temperature. In microsections of all specimens deformed by hammering at —195°C thin lamellae appeared, Fig. 1. They were aligned in definite directions in each grain. In some grains they had two orientations. Where lamellae intersected, a displacement was apparent. Near the center of the left margin of Fig. 1 shear has taken place beyond the fully developed intersecting lamella. Many lamellae resembled Neumann bands in alpha iron. They were parallel to one side of triangular etch pits in the matrix (as in Figs. 1 and 2). The individual lamellae were narrow and had little substructure. This suggested that they did not result from concentrated local slip. The shape of etch pits within the lamellae differed from that of pits in the matrix, as can be seen in Fig. 2; this indicated a difference in orientation. Specimens slowly deformed at —195°C contained regions in which the lamellae were clustered. In these specimens some lamellae were bent and presumably had formed before the termination of the deformation. Structures of greater width than the lamellae were also seen.4 More lamellar structures formed on impact than during slow compression to a given reduction. This was true of all compositions. The structures became less abundant with increasing temperature of deformation. None was observed after extension to fracture at room temperature, but they could be pro-

Jan 1, 1959

By E. H. Kelton, R. D. Grissinger

In designing structural members of steel and some other materials the design engineer has available recognized values of elastic modulus and safe working stress that may be substituted in well-known engineering formulas to give him desired cross-sectional areas and deflections for a particular part. Zinc, on the other hand, has no generally recognized modulus. It flows under continuously applied loads. Therefore, the designer of structural members must use a range of working stresses depending on the continuous load and the amount of permissible distortion. The only method of obtaining these values is by creep testing. Creep testing of zinc has been carried on for some 20 years by this laboratory, covering a wide range of zinc and zinc alloys. Types of test included tension, compression, and simple and cantilever beams at temperatures ranging from o to I50°C. Specimen conditions ranged from as-cast or as-rolled to accelerated aged in steam or dry air. Effects of plating were investigated also. It is not the intention of this paper to expound all these factors but rather to present the final data on well-known zinc die-casting alloys and to suggest means of applying these data to engineering design. Early Work In the early work on creep testing of zinc, the direct-loading tension method was used. However, direct loading of die castings was unsatisfactory because of the high loads required. For instance, a standard die-cast tension bar having a cross-sectional area of about 0.049 sq. in. would require a direct load of about 1000 lb. for a unit stress of 20,000 lb. per sq. in. Also, tests were made at nominal room temperature, but normal variations caused fluctuations greater than those due to experimental error or other causes, so that control of this variable within ±1/2°C. seemed essential. These two factors led to the development of an apparatus described by J. Ruzicka,' in which the specimens were loaded by means of a lever and were held at constant temperature by means of an oil bath. While Ruzicka's apparatus yielded excellent check results, it seemed desirable to have some setup by which literally hundreds of die-cast specimens could be tested at the same time. This would permit the conducting of a number of low-load tests designed to run 10 years or longer and still leave capacity for current high-load work. Beam testing in a constant-temperature room was the answer. Test Method Preliminary work indicated that die-cast beams of various lengths and cross scctions yielded the same result within reasonable limits regardless of whether they were tested as simple beams, uniformly loaded beams, or cantilevers. Accordingly, the simplest type was adopted. This was a,

Jan 1, 1945

By H. M. Dess, S. R. Bolin

A modifiedl Czochralski technique has been utilized to grow single crystals of YVO, pure or doped with europium or neodymium, from 1 to 2 in. long and 4 to 1/2 in. in dianz. An oxyhydrog-en gas-fired furftace zuas used in this ulork, and melts were contained in iridium crucibles. Successful application of the Czochralski ~vzethod was found to depend upon atmosphere control to prevent crusting and to limit melt decomposition, the establishment of symmetrical thermal gradients in the melt to obtain stable growth, and the selection of high-quality single-crystal seeds to prevent propagation of misorientations during growth and subsequent catastrophic cracking. The suitability of YVO4 as a host for laser-active trivalent rare earth ions has long been recognized. However, the problems associated with the growth of sufficiently large, good-quality single crystals have, until quite recently, seriously hindered satisfactory evaluation of the laser potentialities of this material. Both flux growth and Czochralski growth techniques were investigated at an early stage of interest in YVO,. The former method proved incapable of yielding crystals large enough for practical use,ly2 and the latter was beset with difficulties which took some considerable time to understand and overcome. Recently, however, the Czochralski growth process for YVO, has been improved along separate but similar lines of development by groups working independently in the Crystal Products Department of Union Carbide's Electronics Division and Bell Telephone Laboratories3 so that now good-quality single crystals of satisfactory size can be produced on a routine basis. Stimulated emission from a neodymium-doped YVO4 crystal grown by the Crystal Products Department of Union Carbide was obtained by O'connor4 of MIT, Lincoln Labs. An oxyhydrogen gas-fired furnace was used in this work, Fig. 1, and melts were contained in iridium crucibles. The starting material was 99.9 to 99.99 pct pure YVO4 powder purchased from the Chemical and Metallurgical Division of the Sylvania Electric Products Co. Typical impurity levels, determined by spectrographic analyses, were as follows: Si, 50 to 500 ppm Al, Fe, Mg, 5 to 50 ppm Ni, Pb, Mo, Mn, Ce, Cs, 1 to 10 ppm Initially, YV04 powders predoped with neodymium or europium were obtained from Sylvania. Later, however, because of a desire to grow a series of crystals containing relatively broad concentration ranges of these dopants, it proved more convenient to start with pure YV04 and mechanically admix Nd2O3 or Eu@~ powders plus equimolar amounts of V2O5. The empty crucibles were preheated to 1900" to 1950oC, a temperature range where melting occurred readily. The powdered YVO4 feedstock was then added incrementally. However, a marked tendency toward

Jan 1, 1968