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By Stuart Buckley

THE application of hydrocarbon equilibrium data to various problems encountered in refining and in natural gasoline recovery is an old and well established practice. Both generalized data and data on specific hydro-carbon systems have been made available by a number of investigators. More recently such data have been applied to the relations governing the separation of oil and gas both in the reservoir and at the surface. Most of the applications to production problems, however, have been based upon examinations of surface samples of oil and gas. This paper describes a technique that has been used satisfactorily in a number of cases to calculate directly from the hydrocarbon analysis of and auxiliary laboratory data on a subsurface sample of the reservoir fluid the behavior of the oil and gas during the various stages of separation at the surface incident to production.

Jan 1, 1938

By George T. Bator

If confronted with the problem of pumping a mixture of slime-free sand, gravel and boulders up to six in. in diameter, at the rate of 175 tons per hr in one single-stage pump against a static head of 90 ft and a total head of 140 ft, of which 20 is on the suction side, an engineer might be forgiven for backing away from the job, especially if he were also told that the pump wearing parts must have a minimum hardness of 550 Brinell for the sake of abrasion resistance.

Jan 1, 1950

By Byron W. Cheever

Of the elements found in iron and steel, none has attracted more attention than phosphorus. It is considered the great enemy of the steel manufacturer-, and the chief aim has been and is to keep it out by using pure crude material, or when once in, to eliminate it or counteract its effect. Its presence is manifested in various ways, but most of all by producing a condition called cold-shortness. The first question, then, which presents itself is, What per cent. of phosphorus produces this condition ? I have searched very carefully for an answer to this question, but have failed to find one. Authors generally agree that wrought-iron may have a larger per

Jan 1, 1887

By Thomas M. Turner

Open pit mining, always a demanding task, faces two relatively new problems today: (1) availability of equipment and (2) environmental restrictions. The modern dredge offers relief in both problem areas. Delivery on a major dredge might run 18 to 24 months rather than 60 months; and lowering of the water table is precluded, thus minimizing environmental objections. In addition, a lower first cost and potentially increased efficiency may offer real advantages to the miner who is forced away from his traditional mining methods. What are the objections to the use of a dredge in open pit mining? Perhaps first and foremost is the natural reluctance to change from a successful operation. Who can blame the miner who has developed expertise in the use of the dragline if he is reluctant to change to a new mining technique that requires new and different skills? A part of the same problem is the miners' desire to control the excavation visually in order to delineate sharply between overburden and matrix. This problem can be alleviated significantly by utilizing good boring data and a positive acquisition cutter. In the final analysis, however, if the miner is prohibited from dewatering the area, either he mines the deposit by dredge or not at all. There is little doubt that when the decision is made to remove overburden and/or matrix by dredge, the problems of delineating between overburden and matrix, creation of slimes, and development of mining plans to minimize double handling etc., will be addressed and solved. There are two broad categories of dredges: mechanical and hydraulic.

Jan 1, 1976

By James Howard

ON Aug. 25, 1911, a rail failed on the Lehigh Valley Railroad, causing a disastrous wreck. The surface of the fracture was in a plane at right angles to the length of the rail. There was a dark-colored, oval spot on this surface, located on the gage side of the head, representing the part of the rail which was the first to fracture. The nucleus of this spot showed that the fracture had an interior origin. Other fractures of this kind, the peripheries of which had not reached the surface of-the rail, presented surfaces having a silvery luster. The darkened surface of the present fracture was caused, doubtless, by the air having had access to it. This fracture was recognized as a fatigue fracture, of a modified type, its interior origin having been due to a component in the rail which is not usually present in cases of fatigue fractures. The metal next the running surface of the head of the rail was in a state of internal compression, this being the component not commonly met with in other cases, and which caused the fracture to have its interior origin. For the purpose of giving this modified type of fatigue fracture a specific name, for identification, the term "transverse fissure" was applied. No mystery was thought to attach to its formation, or to its development. The explanation of its occurrence was obvious in the light of common knowledge upon the behavior of steel under repeated alternate stresses. By reason of the state of internal compression at the running surface, the maximum tensile stresses in the head, under bending loads, were along an interior element. Here the tensile strains were higher than in the fibers more remote from .the neutral axis. Under such conditions the fracture of the rail would be expected to have an' interior origin. A discussion of the subject of transverse fissures essentially becomes a discussion of fatigue fractures, since they are identical. The descriptive term employed, merely for the identification of this type of fatigue fracture, had the appearance of creating alarm. Apprehensions arose that a new phenomenon in the physical properties of steel had presented itself, the explanation of which was sought in every

Jan 11, 1917

By R. A. Vik, C. B. Daellenbach, W. M. Mahan

The influence of reduction roasting and thermal shock on the grindability of a refractory low-grade Michigan iron ore was examined in bench-scale tests. The quantitative effects of the various treatments were evaluated at three sieve levels, 48, 100, and 400 mesh, with ball-mill-grindability and work-index parameters as response indicators. Data from the testing program were statistically analyzed to isolate the effects of cooling rate, roasting temperature, mesh level, and ore chemical condition. All four variables were found to have an important influence on the grindability of the treated ore. Ore chemical condition and roasting temperature had the most pronounced effects.

Jan 1, 1972

By E. Topuz, G. Faulkner, M. Karmis, C. Haycocks

The Appalachian coal region of Virginia, southern West Virginia and Kentucky and the extreme eastern portion of Tennessee constitutes a unique area of surface coal mining activities. The area contains a number of contiguously placed coal seams, up to a total of fourteen in some places, which vary in thickness from a few centimeters to 2,5 meters. Much of this coal is of high quality, some being the highest grade metallurgical coal found anywhere in the world. The region may be broadly characterized physiologically as a dissected plateau with a relief above the valley floors of up to 500 meters and a dendritic drainage pattern. Up to six seams may outcrop in the hillsides above drainage, many of which have been subjected to contour stripping operations. Prior to the passage of the surface mining reclamation act, little effort was made to reclaim stripped areas. The passage of the strip mining act, including the controversial requirement for returning the land to its approximate original contour, has forced intensive recla¬mation efforts from the mining industry. The wisdom of this original contour requirement has been the subject of considerable debate and litigation, mainly because of its cost, inconvenience, and value of the land after it has been reclaimed. Regardless of whether recla¬mation is carried out, under current practices slope failures do occur. This in effect circumvents the intent of the law and can expose large unvegetated spoil areas, and contribute to hillside erosion and stream silting. Such failures must be eliminated if further costly reclamation efforts are to be avoided.

Jan 1, 1983

By Richard Pearce

In the treatment of auriferous copper containing bismuth, I have recently observed a small quantity of a grayish-white alloy, which on examination, proved to be Bi containing in solution, as it were, a crystalline alloy of Bi and Au. This compound makes its appearance on the surface of the auriferous Cu in small globules as the latter cools. These globules are rapidly attacked by nitric acid, and fine needleshaped crystals of Bi and Au separate out. They arc insoluble even in strong nitric acid. On examination, the crystals mere found to contain : Gold, 69.94 per cent.; silver, 0.63 per cent. ; bismuth, 29.43 per cent. (No. I).* The residue is very fusible, and at a temperature considerably below its melting-point it oxidizes rapidly, changing from its original gray color to a greenish-yellow (No. 2). On melting in a crucible under flux, a bronze-colored alloy is formed that has the specific gravity 15.47—somewhat higher than the calculated specific gravity of a simple mixture of the two metals in the proportions named. Alloys of Gold and Silver.—In following out my investigations by repeated examinations of this alloy formed at different times, I found that, in dissolving a miscellaneous lot of the alloy in nitric acid, some gold-yellow crystals were formed, which I succeeded in separating from the BiAu alloy by washing. These yellow crystals, under the microscope, showed distinct, regular, octahedral faces, and on examination they were found to be a crystalline alloy of Au and

Jan 1, 1885

By Stanley M. Miller

For rock or soil materials assumed to be generally isotropic and homogeneous, seepage theory and analytic geometry can be used to develop a mathematical technique for estimating the steady state, pie-zometric drawdown to a slope face. The resulting parabolic drawdown curve is a function of slope angle and the height of the original water table above the slope toe. When the slope is cut at a rate faster than that which allows a steady state to be attained, a non- steady state analysis approximates the transient drawdown. Monte Carlo simulation provides realizations of possible drawdown curves that can be included in slope stability risk analyses.

Jan 1, 1983

G. F. LOUGhlin,* Washington, D. C.—With reference to Mr. Bain's paper: The scarcity of adequate geologic data on building stone reflects, among other things, a lack of interest on the part of geologists. It has been one of my duties to attend to matters relating to building stone and other structural materials that have come to the U. S. Geological Survey, but for several years my principal administrative and other duties in the Section of Metalliferous Deposits have prevented me from giving structural materials the attention that they deserve. I have felt that investigations relating to structural materials should be assigned to someone else, but thus far nobody with a sufficient interest in the subject has come forward; further, the specific calls for these investigations have been so few and far between that it has not seemed practical to draft any one for the job. The general situation is such that steady and substantial progress in the application of geology to the utilization of structural materials is not likely to be made unless someone with keen interest in the subject takes the initiative. If the start is once made, I know from experience that cooperation from the more progressive members of the quarry and building industries will be readily forthcoming. Mr. Sales' suggestions are all constructive and most welcome. A thorough, detailed discussion of them might be as long as his manuscript, but could largely be summarized with the one word "amen" qualified by the alibi that a chronic shortage of funds and therefore of personnel has prevented us from carrying out some of his suggestions already. A few of them might call for an Act of Congress before we could undertake them, and one or two, such as the preservation of mine maps, with which I heartily agree, would call for much additional space as well as clerical and supervising help. Several items in Mr. Sales' paper—for example, the question of balance between the scientific and more directly practical studies and the surveys or resurveys of the larger and smaller mining districts—have been covered in my contribution to the symposium. The suggestion of frequent reviews of progress in the study of ore deposits is excellent and can be followed without serious diversion from projects already on the Survey's program. Brief reviews by Survey men have been published in periodicals, and the contributions by several of them to the Lindgren Volume1 may also be cited as serving this purpose to some degree. The practice of publishing short papers by Survey men in outside journals rather than in Government reports is largely the result of experience and expedience. Our printing funds are limited, and considerable time must elapse between the transmittal of a paper and its publication. Time is saved therefore by sending papers to outside journals, and the editors of those journals are usually glad to receive them. Members of the Survey would doubtless prefer to have the products and byproducts of their official work appear in official Survey publications if conditions were more favorable. If we were left entirely to ourselves the balance between the more scientific and the more directly practical studies would be somewhat better than it is, but the

Jan 1, 1935

G. F. LOUGhlin,* Washington, D. C.—With reference to Mr. Bain's paper: The scarcity of adequate geologic data on building stone reflects, among other things, a lack of interest on the part of geologists. It has been one of my duties to attend to matters relating to building stone and other structural materials that have come to the U. S. Geological Survey, but for several years my principal administrative and other duties in the Section of Metalliferous Deposits have prevented me from giving structural materials the attention that they deserve. I have felt that investigations relating to structural materials should be assigned to someone else, but thus far nobody with a sufficient interest in the subject has come forward; further, the specific calls for these investigations have been so few and far between that it has not seemed practical to draft any one for the job. The general situation is such that steady and substantial progress in the application of geology to the utilization of structural materials is not likely to be made unless someone with keen interest in the subject takes the initiative. If the start is once made, I know from experience that cooperation from the more progressive members of the quarry and building industries will be readily forthcoming. Mr. Sales' suggestions are all constructive and most welcome. A thorough, detailed discussion of them might be as long as his manuscript, but could largely be summarized with the one word "amen" qualified by the alibi that a chronic shortage of funds and therefore of personnel has prevented us from carrying out some of his suggestions already. A few of them might call for an Act of Congress before we could undertake them, and one or two, such as the preservation of mine maps, with which I heartily agree, would call for much additional space as well as clerical and supervising help. Several items in Mr. Sales' paper—for example, the question of balance between the scientific and more directly practical studies and the surveys or resurveys of the larger and smaller mining districts—have been covered in my contribution to the symposium. The suggestion of frequent reviews of progress in the study of ore deposits is excellent and can be followed without serious diversion from projects already on the Survey's program. Brief reviews by Survey men have been published in periodicals, and the contributions by several of them to the Lindgren Volume1 may also be cited as serving this purpose to some degree. The practice of publishing short papers by Survey men in outside journals rather than in Government reports is largely the result of experience and expedience. Our printing funds are limited, and considerable time must elapse between the transmittal of a paper and its publication. Time is saved therefore by sending papers to outside journals, and the editors of those journals are usually glad to receive them. Members of the Survey would doubtless prefer to have the products and byproducts of their official work appear in official Survey publications if conditions were more favorable. If we were left entirely to ourselves the balance between the more scientific and the more directly practical studies would be somewhat better than it is, but the

Jan 1, 1935

By Sterling G. Valentine

The annual .use of large quantities of sulphurous iron-ores (over 1,500,000 tons in the United States) has led to a search for the best methods of desulphurization, in order to make this material more available for the manufacture of a good quality of pig-iron. Although such ores can be used raw in small amounts, they must be previously roasted if they are to constitute the entire ore-charge of a furnace.

Jan 1, 1890

By William R. Webster

In view of the good results which have followed the wide discussion of the rail-specifications of the American Section of the International Association for Testing Materials, I now offer for discussion its specifications for steel forgings and steel castings. It is not necessary to emphasize the importance of reaching definite conclusions on these subjects. Engineers, consumers and manufacturers are alike interested in securing good, reliable, uniform steel. In this connection, I would call particular attention to the important paper read by Mr. C. H. Ridsdale, last September, before the Iron and Steel Institute, as bearing on them; and, for convenience of reference in the discussion, I append the Table in Section VI. of his paper, on a Manifestations, Classified mider Heads of Faults of Different Types. appearing after Treatment by the User, for Tracing their Probable Source."* The discussion of these specifications will be practically a continuation of our former discussions on "The Physics of Steel." We have passed through a period in which the chemical composition of steel has received the greatest prominence; but failures of steel forgings and castings of the best chemical composition have shown that we could not control the quality of the finished product by the chemical composition alone. It must be admitted that differences in the physical properties of the steel, greater than those due to small variations in composition,are produced by heat-treatment, both in connection with the mechanical work of forging and otherwise. The present result is a strong tendency to deem the heat-treatment more important than the chemical composition. I think the mean course is the safer. We should give them equal importance; for we know that to produce the best results me must start with a good

Jan 1, 1903

By R. D. Pehlke

THE impending commercial importance of iron-aluminum alloys has served as a stimulus for re- search on the preparation and properties of these alloys. However, the activities of the components of the binary system remain undetermined. The experimental determination of the thermodynamic properties of binary solutions of iron and aluminum has been hindered by the high liquidus temperatures

Jan 1, 1959

By S. C. Lee

An uncoupled thermoviscoelastic finite element formulation with an application to Underground Coal Conversion (UCC) is presented. An incremental solution procedure with an implicit time stepping scheme is used under the thermorheologically simple material (TSM) postulate. The presented formulation, for a homogeneous and isotropic medium, is employed in the simulation of the UCC post-burn phase. Temperature, displacement, stress, and failure responses under thermomechanical loading are predicted. The solutions for the selected field problem indicate potential roof collapse, stress relaxation, and modest surface subsidence with a progressive thermal and failure front. The corresponding thermoelastic responses with temperature- dependent elastic properties are also presented and compared with the thermoviscoelastic results.

Jan 1, 1984

By William Hamilton Merritt

Since 1880 the occurrence of gold-ore has been known in the Lake of the Woods district. In 1879 the writer examined a so-called silver-location in the lake. More recent developments have extended, south and east, to the Rainy lake and along the Seine river, which flows from the northeast into the Rainy lake. The gold occurs in quartz-veins in the Huronian series. These Huronian rocks occur in belts in the Laurentian; the latter being the predominant formation in the eastern part of Ontario.

Jan 1, 1897

By O. W. Bilharz

INTRODUCTION 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 considered 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 Pennsylvanian 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 on 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 openings. These products of oxidation can be seen today in the old mines of the district as crusts of crystalline sulphates

Jan 1, 1947

By G. J. Heuer, J. N. Dew, G. C. Clark

The effect on well behavior of partial permeability barriers, changes in producing rates and well spacings have been calculated through use of a radial, unsteady-state, two-phase-flow mathematical model. This model allows for variations in permeabilities and porosities with distance from the wellbore. The numerical methods necessary to solve the problem require use of a highspeed digital computer, in this case an IBM 704. In each instance, pressure and saturation gradients, gas-oil ratios and recoveries around a well producing by solution-gas drive have been calculated as a function of time and distance from the wellbore. Comparisons are made to show the effect of changes in producing rate and of varying permeability near the wellbore and out in the formation on the production and pressure history of the well. The effect of different well spacings on producing rate and ultimate recovery is considered. Although the mathematical description of the reservoir is simplified in comparison to an actual reservoir, the results do give some insight into the difficult problem of spacing and proration in a heterogeneous solution-gas-drive reservoir. Results show that for the cases considered spacing has little effect on ultimate recovery and that permeability barriers removed from the well decrease producing rate for a period of time but have only a small effect on ultimate production. INTRODUCTION The effect of spacing and producing rate on the production characteristics and ultimate recovery of a well producing by the solution-gas-drive mechanism have been topics of interest to the oil industry for many years and the subject of many hearings before state regulatory bodies. The problem is very complicated because of the difficulty of simulating in the laboratory a reservoir producing by the solution-gas-drive mechanism under anything like normal field conditions. This paper gives the initial results of a study aimed at determining the effect of these factors on production from reservoirs simulated by a mathematical model. Two-phase, unsteady-state equations are used to calculate pressures, saturations, and rates of oil and gas flow as a function of time and distance from the wellbore. The model is radial, and reservoir properties may be varied with distance from the wellbore. A decrease in permeability at a given distance results in a low-permeability ring concentric with the wellbore through which all the fluids from more distant portions of the reservoir must flow. The current mathematical model allows for variation of permeability, porosity and saturations as a function of distance from the well. Any desired drainage radius for the well may be selected. Drainage radii of 745 and 1,053 ft, which correspond to 40- and 80-acre spacing, were chosen for the calculations which follow. A large amount of the input data has been held constant. No investigation was made into the effect of changes in fluid properties and relative permeability characteristics on oil and gas production behavior. Fluid properties and relative permeabilities are essentially those of the White Mesa portion of the Greater Aneth area in southeastern Utah. A recently concluded hearing before the Utah Oil and Gas Conservation Commission to determine spacing for the field aroused interest in the possible effect of permeability constrictions located some distance from the well on production and recovery. This interest stimulated the present study. In this paper, no attempt has been made to simulate any field production characteristics exactly. Only the solution-gas-drive mechanism has been investigated, and production by liquid expansion has not been considered. This investigation is exploratory in nature but does give some insight into the problems of spacing and proration in a solution-gas-drive field having permeability variations. THE MATHEMATICAL MODEL The mathematical model is similar to that proposed by West, Garvin and Sheldon.' Approximately the same techniques have been used in arriving at a solution. The equations are nonlinear, partial differential equations which have been known for some time. The particular equations used for this study neglect the effects of capillary pressure and gravitational forces. The advent of modern digital computing equipment has made their solution practical. Basically, the method solves for pressure, saturations, and oil and gas flow rates as a function of distance and time. In our model, distance to the

By V. Miller

Highly variable milling procedures within a geologically complex porphyry copper deposit owned by Kennecott Corp. in Nevada made it necessary to estimate copper recovery and concentrate grade in areas where actual test data was lacking. Estimation was made by first determining the relationships between desired metallurgical properties and the ore's petrology-copper mineral type, rock type, and copper grade. This relationship was then combined with previously estimated rock type, mineral type, and copper grade data in the mineral block model to predict milling properties.

Jan 1, 1985

By C. J. Barber

This paper Donald describes how New Jersey Zinc Co. made surveys for a connection between the Ivanhoe and Van Mater shafts at Austinville, Va. Except to say that the two faces had to meet "accurately" on line and grade, Donald does not indicate the required precision. Assuming that there were 24 angles in the 1 ½ -mile traverse and 15 in the one-mile traverse, it can be shown that if the average error in plumbing each shaft was ±30" and the average error in measuring each traverse angle was ±10", then the average error at the point of connection would have been about ±1.9 ft normal to the line between the shafts. This calculation assumes that any errors in the triangulation would be negligible compared with the errors in the plumbings and traverses, and it also neglects taping errors. With no constant errors or blunders, the latter would be important only in lines normal to the line between the shafts.

Jan 7, 1959