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By Dean F. Winchester, C. D. Johnson

The so-called Rocky Mountain region is here made to include Colorado, Idaho, Montana, northern New Mexico, Utah and Wyoming, an area of great distances and relatively sparse population. Conditions of distance, transportation and markets have had their retarding influence on devolopment and production but the increase in facilities and markets in recent years has provided additional incentive for more thorough search for new productive areas and the more complete development of the known fields. The low prices of crude during the past year have offset, to a certain extent, the desire for increased production and much of the effort has been directed therefore to outlining new areas rather than to attempts to increase production from known fields and thereby add to the already sufficient supply above ground. During the year just closed the Rocky Mountain region has seen consistent efforts to outline new areas and these efforts have been reasonably successful. In this area a very large part of the land is government property, and by cooperation between the government, the private owner and the company it has been possible to carry on development in a scientific manner, providing for the maximum recovery of valuable products at least cost and at times when prices were best. Due to the fact that in the Rocky Mountain region costs of exploration and development are relatively high because of natural circumstances, it has been the policy of operators to drill test wells only on structures where they controlled a large proportion of the land. Even community lease programs have been effected in certain areas, thus obviating the necessity of offset drilling and the attendant uneconomical and even wasteful production. Oil production in the Rocky Mountain states has shown a slight increase during the year, the average daily production for November being 78,124 bbl. as against an average in January of 76,681 bbl. The total production during the first 11 months of the year, according to the U. S. Burcau of Mines, was as follows:

Jan 1, 1929

By L. H Levenson, Charles S. Barrett

The orientation of metal crystals and grains, both large and small, can be detcrmined conveniently and accurately without the use of X-ray apparatus. This seems to be appreciated by so few metallurgists that it may be useful to explain in detail the method we have found most satisfactory in the laboratory—the reflection of light from crystallographie etch pits. This note includes a description of a suitable inexpensive instrument and instructions for etching various metals and for plotting the data. As the stereographie projection is used to facilitate handling the data, this note may he considered as an appendix to an earlier review of the metallurgical uses of the stercographie projection.' Various methods involving etch pits have been used by other investigators. Bridgman's method2 consists of attaching the specimen to a sphere (a transparent sphere is convenient4 , holding it at arm's length, and marking a spot on it when it has been turned so that the eteh pits reflect light into the eye of the observer from a lamp standing behind him. It has an accuracy of about 2" and is extrernely rapid. A greater accuracy can be obtained by having the reflected light fall on a screen, as has been done by Czochralski,5 Chalmers,6 and Schubnikov.7 All of these methods have been intended for undeformed single crystals. Tammann and his coworkers3,8 developed a method for estimating the number of grains in a polyerystalline aggregate having orientations in a given region of the stereographic triangle and thus obtained statistical information about deformation and reerystallization textures. While the method has had some use in recent years,9 it is not applicable to the majority of problems in physical metallurgy. Smith and Mehl10 determined orientations by plotting the directions of the sides of individual etch pits on a stereographic projection. The accuracy is limited to about 3" and the method requires careful polishing and high magnification.

Jan 1, 1940

By A. S. Nowick, A. E. Roswell

Anelastic measurements of atomic mobility in an Ag-Zn substitutional solid solution, make possible a study of the rate of decay of lattice defects frozen into the alloy by quenching. A WIDE variety of experimental evidence has accumulated recently in support of the belief that atomic mobility or diffusion in face-centered cubic lattices occurs principally through the movement of lattice defects, as contrasted to a mechanism by which two or more atoms directly exchange lattice positions. The most direct evidence, summarized in a recent review,' includes the Kirkendall-effect measurements and anelastic measurements on quenched alloys. Theoretical calculations' have focused attention on the lattice vacancy as the defect probably responsible for diffusion in the common metals. Later calculations3 have also shown the possible importance of combined pairs of vacancies in producing diffusion. The only defect that has been considered seriously, in addition to the vacancy and combination of vacancies, is the "interstitialcy" (an atom which has left its normal lattice position and entered an interstitial position) ; the calculated energy of formation of an interstitialcy in a close-packed lattice is too large to permit a reasonable probability for the occurrence of this defect In view of these calculations it may be tentatively concluded that the defects producing atomic movements are single or multiple vacancies. Anelastic measurements of atomic mobility in substitutional solid solutions provide a valuable method for the study of lattice defects. By means of this method it was first demonstrated' that defects may be frozen into a lattice by rapid quenching from high temperatures. (It was subsequently shown6 that resistivity measurements may also be capable of detecting the presence of frozen-in defects.) A summary of the principles involved in these anelastic measurements will now be presented. The anelastic method is based on a relaxation phenomenon in substitutional solid solutions, first discovered by Zenera in a brass and subseauentlv investigated extensively in a series of Ag-zn solid solutions.' This relaxation effect may be observed in the usual way either dynamically, as a peak in

Jan 1, 1954

By Otis Hutchins

IT is intended to discuss in this paper the protection appliances used for high-temperature pyrometer installations involving the use of platinum couples and describe some of the characteristics of a new carborundum protection tube. Of all the components that go to make a complete pyrometer installation, the one given the least attention and the one about which there is the least exact information is the outer protection tube. This condition is unfortunate as much, and in some cases even the success of the equipment as a whole, depends on the proper type of protection. In the majority of cases, the installation is allowed to operate without attention until some part of the apparatus breaks clown. The outer tube is the component that usually fails and, more often than not, the failure causes breakage of the porcelain protection and ruin of the couple. This condition should be recognized and studied as it has a very important bearing upon the upkeep cost of pyrometer equipment. The cost of the outer protection tube is small compared with the cost of the platinum couple and procelain protection and it would well repay users of this type of equipment to replace their outer protection tubes at certain definite periods, which experience shows is necessary to prevent destruction of the platinum. Speaking generally, platinum thermocouple equipment is used for measuring temperatures over 2000° F. (1094° C.), and is used extensively for the control of brick and pipe kilns, glass pot furnaces, glass tank furnaces, heat-treating furnaces, open-hearth furnaces, and forge furnaces. A satisfactory protection tube must be sufficiently refractory not to soften at the maximum temperature within the furnace. It must be resistant to cracking clue to temperature changes, should be as nearly gas-tight as possible, and should be made of a material with a high thermal conductivity and great resistance toward erosion by the furnace atmosphere.

Jan 9, 1919

By F. A. Jerabek, H. L. Hartman

This study presents results of investigations in a small model of segregation in discharged fill slurry, the quantity of solids escaping in the drain liquid, and the relationship of solids to slurry concentration and discharge rate. Compressibilities of fine fill material, in dry and wet states and individual size fractions, are compared. Two terms are frequently used in describing the hydraulic placement of fill material underground: hydraulic stowing is mostly associated with the underground flushing of coarse-sized fill material, such as coal washery refuse; while hydraulic backfilling refers to placement of small-sized fill material, e.g., sand or classified mill tailings, mainly in metal mines. Characteristically, in backfilling, only a few hours may elapse between the time the material is hoisted as ore and redeposited as fill underground. Hydraulic filling was first used about 100 years ago to control subsidence in coal mines. It was subsequently adopted in many mining operations all over the world, but its basic concepts have never been adequately studied and analyzed. This is not surprising, when one considers the number of variables involved in the hydraulic backfilling operation. Recently, much work has been done on the problems of transportation of slurries in pipes. Comparatively less research work has been done concerning the physical properties of fill material (compressibility, cementation, permeability, etc.). Very little work has been done on the problems of fill placing, distribution, and segregation of fill material discharged in the mine void. It is the purpose of this paper to explore two of the basic, lesser known aspects of filling: segregation and compressibility in discharged fill slurry. Difficulties in observing the behavior of hydraulic fill slurry during the pouring operation underground, and insufficient knowledge to conduct any kind of meaningful theoretical analysis, suggest experimental model studies. The tests described in the following sections were conducted in the Rock Mechanics Laboratory of the Department of Mining at Penn State.

Jan 1, 1965

By W. N. Roberts

Hadfielcl steel has been studied by transmission electron microscopy to determine the microsl.rtic-ture of the cold-worked material, which has been a subject of controversy for many years. The presence of fcc deformation twins in specimens deformed in tension, by hamnzering, and by explosive -shock loading at room temperature lzas been established by electron diffraction. No evidence of a mar tensite was detected in any of the speciwens. Small amounts of E martensite were idenLified in the hamnleved specimens. DESPITE numerous researches on Hadfield steel since its discovery in 1882, there is still disagreement on the nature of transformations in the cold-worked material. Collette el al.,' using X-ray and electron diffraction, have found evidence for stacking faults, E martensite, and a martensite in Hadfield steel deformed in tension at room temperature. Nishiyama and Simizu,' using electron microscopy, have found stacking faults and E martensite in hammered Hadfield steel. White and Honeycombe have concluded from X-ray diffraction that Hadfield steel remains fully austenitic even after severe cold work at -196 Previous work by the author, indicating the presence of a, martensite in deformed Hadfield steel, was in error due to a faulty interpretation of the electron-diffraction patterns. Various workers,5'7 over the years, have speculated on the presence of deformation twins in Hadfield steel, largely from such circumstantial evidence as the persistence of slip bands with repeated polishing and etching, the presence of serrations in the stress-strain curve, and the absence of evidence of a martensite by X-ray measurements. The advent of electron-transmission microscopy and se- lected-area diffraction has made possible the positive identification of fine deformation twinning. PROCEDURE For tensile tests, standard ASTM specimens of 2-in. gage length, ground from 0.12-in. Hadfield steel sheet, were solution-treated at 1050°C for 30 min in a salt bath, to avoid decarburization, and water-quenched. The grain size was about 0.01 sq mm. Chemical analysis of the steel after heat

Jan 1, 1964

By Charles S. Barrett, L. H. Levenson

The orientation of metal crystals and grains, both large and small, can be detcrmined conveniently and accurately without the use of X-ray apparatus. This seems to be appreciated by so few metallurgists that it may be useful to explain in detail the method we have found most satisfactory in the laboratory—the reflection of light from crystallographie etch pits. This note includes a description of a suitable inexpensive instrument and instructions for etching various metals and for plotting the data. As the stereographie projection is used to facilitate handling the data, this note may he considered as an appendix to an earlier review of the metallurgical uses of the stercographie projection.' Various methods involving etch pits have been used by other investigators. Bridgman's method2 consists of attaching the specimen to a sphere (a transparent sphere is convenient4 , holding it at arm's length, and marking a spot on it when it has been turned so that the eteh pits reflect light into the eye of the observer from a lamp standing behind him. It has an accuracy of about 2" and is extrernely rapid. A greater accuracy can be obtained by having the reflected light fall on a screen, as has been done by Czochralski,5 Chalmers,6 and Schubnikov.7 All of these methods have been intended for undeformed single crystals. Tammann and his coworkers3,8 developed a method for estimating the number of grains in a polyerystalline aggregate having orientations in a given region of the stereographic triangle and thus obtained statistical information about deformation and reerystallization textures. While the method has had some use in recent years,9 it is not applicable to the majority of problems in physical metallurgy. Smith and Mehl10 determined orientations by plotting the directions of the sides of individual etch pits on a stereographic projection. The accuracy is limited to about 3" and the method requires careful polishing and high magnification.

Jan 1, 1940

By W. L. Phillips

The recovery properties of compression-deformed lithium fluoride single crystals were investigated as a function of prior strain, annealing time, and annealing temperature. The recovery process was studied by observation of etch pits and birefringence stress patterns. The recovery process involved first a redistribution of the dislocations and then a decrease in their number. Only by annealing at high temperatures after small strains (<0.02 in. per in.) was it possible to obtain complete recovery of mechanical properties. LITHIUM fluoride affords unusual opportunities to extend the knowledge of deformation mechanisms of nonmetallic crystalline compounds. Single crystals of high purity are readily available. These crystals deform by slip on the (110) <110> system.&apos; Unlike those of several other ionic crystals, the stress-strain curves of annealed lithium fluoride are reproducible.2 Dislocations generated in the crystals during deformation can be revealed by etch pits.3 This fact makes possible more detailed studies of mechanisms than is usually the case with metals. Also, because lithium fluoride is transparent, it is possible to follow the recovery process with birefringence stress patterns. It has been shown that with metals an increase in temperature increases the amount of recovery for a given time, and the amount of recovery increases with increasing time at the same temperature.4-6 The yield stress has also been shown to be dependent on the rate of cooling after annealing.&apos; Annealing germanium, a covalent-bond material, at high temperatures after deformation redistributes the dislocations and reduces their number. The purpose of the present paper is to extend the knowledge of recovery properties to an ionic crystal, lithium fluoride. The effect of strain, time, and temperature of recovery on the stress-strain curve was investigated. The recovery process was followed by observations of etch pits and birefringence stress patterns. EXPERIMENTAL PROCEDURE Specimens measuring approximately 0.10 by 0,10 by 0.30 in. long were cleaved from a single bulk

Jan 1, 1961

By William G. Krantz

The increased service demands on some of the products of the National Mallcable Castings Co. prompted it about eight years ago to investigate the electric furnace, both in America and in Europe. The process had already been sufficiently developed in Europe to lead us to believe that the electric furnace would most nearly meet our requirements. After further investigation and consultation with the highest authorities on the subject, we decided upon the Heroult type as the simplest and most practicable. In 1910, we built a furnace of this type, of 300 Ib. capacity, for experimental purposes, and although it was crudely constructed the quality of the material we were able to make justified the installation of a 6-ton Heroult furnace in 1912. This furnace has three electrodes, 17 in. in diameter, uses three-phase, 60-cycle current, and is equipped with Thury regulators, which give US good regulation and a uniform load on the line even when cold melting. The power factor of the furnace is 04 per cent. Since July, 1912, the furnace has been in continuous operation, producing up to the present time over 20,000 tons of both carbon and alloy steels of varying analyses and of exceptional quality. Both cold-and hot-metal charges have been used, with a power consumption of about 150 kw-hr. per ton in the case of hot-metal charges and from 500 to 600 kw-hr. per ton in the case of cold charges. The electric energy consumed varies according to the final analysis of the steel and the amount of refining required. Too much cannot be said about the refining possibilities of the electric furnace, for no other method of steel manufacture can compete with the electric in this respect. In proper operation lies the whole secret of success. That steel has been made electrically means nothing, for when the furnace is operated under oxidizing conditions the quality is no better than that of open-hearth material; but when properly made, electric steel is as good as

Jan 1, 1916

By A. Q. Tool

THE necessity of accurate temperature measurements in the glass-making industries is today being much more widely appreciated than in the past. The introduction of the modern simplified and perfected pyrometric methods in connection with exact regulation of furnace temperatures has caused a marked improvement in the glass product with a quickened rate of production. An example of the processes in which much improvement has been and still can be made is that of annealing or heat-treating the glass. This is one of the most delicate processes in glass manufacture and one that requires a most careful furnace control. The heat treatment is undertaken to decrease the possibility of breakage and, in glass for fine optical instruments, to prevent serious warping of accurately ground and polished surfaces and to make the glass more uniform throughout to the passage of light waves. These objects are accomplished by removing all the harmful stresses that exist in a piece of glass when it has been cooled too quickly or unevenly. Such stresses exist, for example, after it has been pressed, cast, or otherwise worked. Thus the process of annealing consists of heating the glass evenly to the temperature at which it softens just enough to relieve these stresses in a reasonable time and then cooling slowly and uniformly until the glass hardens again. Accordingly, the things that must be investigated and determined in order to anneal glass without loss of time are, the annealing temperature, the time that the glass should be held at this temperature while the stresses relax, and the quickest cooling procedure that will give satisfactory results. After these characteristics of the glass are known the problem is one of pyrometry and temperature control entirely. In cases when it is known that a glass article will be required to withstand some definite type of heat or mechanical shock it is often possible, by a proper heat treatment, to produce such a distribution of the stresses in the glass that it will be enabled to resist these shocks more effectively.

Jan 9, 1919

By Paul Hunt

UP TO June, 1923, the Park-Utah mine had shipped about 94,000 tons of a direct-smelting ore of a gross value of $4,200,000, or about $45. a ton. These values were in gold and silver only, although the ore carried small amounts of lead, copper and zinc. Freight, treatment and deductions had averaged $15.40 a ton. At the expiration of the Pittman Silver Act there was in sight about 30,000 tons of a similar ore with a gross value of about $15 a ton in gold and silver, and a large body of partly developed lead-zinc ore of a gross value of about $20 a ton, 40 per cent. of which was represented by the lead-zinc content and the balance by the silver and gold. Mine costs had been high during the life of the Pittman Act, but as a large part of the profits had gone into equipment of the mine and the orebodies were large and had good walls, we knew that mine costs could be greatly reduced. We were therefore faced by the necessity of getting lower freight and smelter rates or of concentrating the ore. We did obtain better freight rates on lower grade ore, and a favorable smelting rate on the small tonnage of siliceous silver-gold ore, but this smelter rate could not be applied to the lead-zinc ore with any profit to ourselves. The Judge mill of the Park City Mining & Smelting Co., with which we were affiliated, was running to capacity; if we built our own mill it meant a 5-mile freight haul to a satisfactory millsite and a year&apos;s delay. Fortunately, the International Smelting Co. had just inherited a mill at Tooele which, with some changes, was about double the capacity required for its own ores. Flotation tests were run on Park-Utah ore and a contract entered into with a low base treatment charge per ton, the tariff being largely fixed by the metallurgical deductions. This contract has been admirably calculated so that the miner can follow a lean orebody to its limit. Such a procedure has no doubt made it difficult for the smelting company at times, but it has resulted in finding ore extensions that otherwise might have been missed, so in the long run it has profited too. A flat rate per ton would have been like mining up to the claim endlines in a great many of the stopes. In order to offer such a contract it can be inferred that the smelting company must have been able to make high recoveries and high-grade products on a very lean ore.

Jan 1, 1928

By F. C. von der Weid

THE mining district of São Fidelis, in the northern part of the State of Rio de Janeiro, is situated on the Paraiba River, where it crosses the Serra do Mar (Mountain of the Sea), in the center of a mountainous country having numerous graphitic outcrops. For a long time, these outcrops were irregularly explored by local people, who had little means and no technical advice. A few years ago, the Cia. Brasileira de Mineração de Grafite took over the control of some of the more important outcrops and entrusted to me the task of studying the ores and establishing a flowsheet for a pilot plant to be situated in Sao Fidelis-the ore to be concentrated being mostly of a very high grade. MINERALIZATION AND ORES The rocks of the district are mostly gneiss and crystalline schists, with occasional interstratification of dolomitic limestone belonging to the Archean Brazilian Fundamental Complex. The general direction of the beds is roughly between 60° and 80°E., with variable dip, generally nearly vertical. Mostly, direction and dip of the graphitic outcrops is concordant with the embanking gneisses or schists. These outcrops seem to be aligned in two or three parallel zones (Pádua, São Fidelis, Macabú), the São Fidelis zone being the best known and the most important to date. Two outcrops of the São Fidelis zone, Saudade and São Benedito, are now being exploited. Mining has been carried out, so far, on a small scale. The mineralization consists of a vein of nearly massive graphite in a very compact, partially granitized gneiss, with vertical dip. The vein is most irregular, with nests and lenses irregularly distributed along the fracture plane. The ore consists chiefly (particularly in São Benedito) of massive graphite appearing and disappearing along the main direction of the vein, forming a succession of irregular lenses in a sort of rosary design. The average width is more or less one foot, with variations from zero to 6 feet. The lode minerals are quartz, a little feldspar and garnet (the latter having its origin perhaps in the embedding gneisses), with rare ferruginous clays on the outcrops. In Saudade a little pyrite, pyrrhotite and chalcopyrite is found occasionally, as well as a carbonaceous mineral, very light, black and shiny, with conchoidal fracture, looking like a sort of jet. The composition of this mineral has not yet been established, but it seems to be very complex. The mineralization seems to be hydrothermal at a rather low temperature, perhaps mesothermal. The paragenesis, according to samples from Saudade, seems to be as follows, the earlier minerals being listed first: pyrrhotite, pyrite, chalcopyrite, with quartz concomitant to the three and

Jan 1, 1946

By I. Fatt

Networks of resistors are used as analog computers to obtain relative permeability and resistivity index curves for networks of tubes. These curves have all of the characteristics of those obtained on porous media and, therefore demonstrate the validity of the network of tubes model. INTRODUCTION In paper I&apos; of this series the network model was shown to give information on the structure of porous media that could not be obtained from the bundle of tubes model. The agreement between the capillary pressure characteristics of a network of tubes and those of typical porous media does not prove the validity of the network made. The bundle of tubes model, although it gives less information, also shows this agreement. In this paper the flow properties of a network of tubes are shown to be in agreement with flow properties of porous media. The flow properties of the bundle of tubes model are not in adequate agreement with those of porous media. The dynamic properties of porous media, such as fluid permeability and electrical conductivity, have been found experimentally to be more sensitive functions of structure and pore size distribution than are the static properties such as porosity and capillary pressure characteristics. The network model can, therefore, be best tested by comparing the dynamic properties of a network of tubes with the observed properties of porous media. All static and dynamic properties of a completely valid model must agree with the observed properties. The most commonly measured sensitive dynamic properties are the relative fluid permeability and the relative electrical resistivity. Experimental measurements of these dynamic properties on sandstone, sintered glass, sintered alumina, and soil are reported in the petroleum and soil science literature. These properties were chosen, therefore, for the test of the network model. In the network model, relative permeability is the permeability of the network when some of the tubes are not conducting fluid, relative to the permeability when all tubes are conducting fluid. Similarly, the relative resistivity is the electrical resistivity of the network of tubes when some of the tubes are filled with a nonconductor. relative to the resistivity when all tubes are filled with the electrical conducting fluid. Single Size Tube Network The simplest porous medium is one in which all pores are of the same size. Such media can be approached by packing beds or columns of uniform size particles of sand, glass, or metal. The model of such medium in this study is a network of single size tubes. The network form, the ß factor, is usually not known for real porous media. If the validity of the network model can be established, then the study of the flow properties

Jan 1, 1957

By H. Q. Golder

With the development of open-pit mines of ever increasing depth, the stability of the pit slopes in soil and rock is of growing economic importance. How is it, considering the newness of the problem that we know anything at all about the stability of man-made slopes? How much do we know and how did it all begin? We can make a reasonable estimate of the stability of a slope in soil, but we know as yet woefully little about slopes in rock because the problem is much more complex. It is only with the development of the capacity of the computer to handle wearisome calculations that any but the simplest of stability problems in rock have become possible of solution. But what we do know is a guide of immense value in the design of slopes in rock. But remember that the computer is a great elevator; it takes everyone&apos;s feet off the ground! So our study began with soils and what is now known as "Soil Mechanics", which is a translation of the German term "Bodenmechanik". It is a pity that the title of Terzaghi&apos;s book "Erdbaumechanik" was not used instead. But here the task of the translator is difficult because English lacks the facility of German to string together several words and make a new one whose meaning is unequivocal. Thus, we have the three German words &apos;Erde&apos; &apos;Bau&apos; and &apos;Mechanik&apos;. &apos;Erde&apos; means "earth" in almost all the English senses including "soil". &apos;Bau&apos; and &apos;bauen&apos; convey the meaning of building and construction, and &apos;Mechanik&apos; means "mechanics" which includes statics and dynamics and the &apos;mechanics of materials&apos;, etc. So that a correct translation of the German is a phrase like "the mechanics of construction with, in or on, earth or soil." However we are stuck with &apos;Soil Mechanics&apos; and that is where it all began. Now this study or subject did not begin with &apos;Terzaghi&apos; although his contribution to the subject is unquestionably greater than that of any other single person. Every scientific discipline has its &apos;classical problem&apos; and that of soil mechanics is &apos;the earth pressure problem&apos; and it began in the 17th century. In fact, it probably began before this with the introduction of gunpowder to Western Europe in about the 15th century, but the first known reference to the problem was by Vauban, a distinguished French military engineer who lived from 1633 to 1707 and who gave rules for the dimensions of retaining walls from 6 to 80 ft. in height. The soil properties were not mentioned by Vauban probably because the rules were intended to be applied to fortifications only, but Poncelet (1840) claimed that Vauban&apos;s rules were based on a theory, and not simply on military and practical

Jan 1, 1972

By Horace W. Hindry

This paper presents the ingredients composing a type of oil-base mud that has been successfully used in drilling oil horizons in California, the effect of ingredient concentrations on physical properties, methods of handling at the well and possible advantages of a waterless drilling fluid with excellent plastering properties. INTRODUCTION AN oil-base mud is a rotary drilling fluid in which oil has been substituted for water as the principal liquid ingredient. In recent years such a mud has been developed and used successfully for drilling the oil horizons of wells in various California fields. There are several types of oil-base mud, but only the type that is currently used to any appreciable extent will be considered at this time. The oil-base drilling-mud compositions used by Shell Oil Company, Incorporated have been covered by several patent applications on which patents are expected to issue at an early date. The purpose of this paper is to present data on the fundamental design of the mud; the ingredients used and their specifications; the effect of ingredient concentration on physical properties; the selection of the proper mud; the facilities needed for handling the mud; and a general discussion [oil] drilling with oil-base mud. In view of the early stage of development of oil-base mud, the great number of variables, and the almost unlimited possible combinations of these variables, which in turn require extensive laboratory study, there are certain irregularities and omissions in the data presented here. However, it is believed that sufficient data are at hand to permit a fairly complete analysis of the characteristics of oil-base muds. In view of the excellent plastering properties of oil-base mud when properly proportioned, its use should: (I) minimize the possibility of impairing the natural flow potentialities of the producing horizon such as that resulting from infiltration of water from water-base muds; (2) permit smaller clearances for setting liners, since the mud sheath has no appreciable thickness; (3) eliminate the possibility of clogging the perforations of the liner with thick mud sheath; (4) facilitate the removal of the mud sheath from the walls of the hole, for its mud sheath has no appreciable strength; (5) assist in drilling through formations, such as "heaving shale," where water wetting appears to be a source of difficulty. (6) permit cores to be obtained without contamination from drilling water. FUNDAMENTAL DESIGN OF AN OIL-BASE MUD In the design of any rotary drilling mud it is necessary to select materials that will fulfill the following requirements: (I) act as the liquid medium and regulate the viscosity; (2) impart initial and final plastering properties; (3) give gel strength and structure in order to prevent settling; (4) serve as a weighting material. The

Jan 1, 1941

By J. S. Kennedy, A. A. Lerew, C. M. Judson, G. L. Simard

DITHIOPHOSPHATE collectors are commonly used in the flotation of sulphide minerals. Studies of the interaction of a typical dithiophosphate collector with galena surfaces have been previously reported from. these laboratories." These fundamental studies were carried out by employing phosphorus labeled radioactive dithiophosphate. Radioactivity determinations then could be used to measure readily and accurately the small concentrations of dithiophosphate that, are present under conditions of flotation processes. Measurements were made on ground mineral, determining the amount sorbed indirectly from the concentrations in solution; and studies were also made with single crystals, determining the amount sorbed directly by counting the crystal surface. The rates, isotherms and reversibility characteristics of dithiophosphate sorption, the competition between phosphate and dithiophosphate for the mineral surface, and the exchange of sorbed dithiophosphate with dissolved dithiophosphate were studied. These studies have now been extended by sorption measurements in flotations with a Fagergren, machine. For this work, the selective flotation of galena and sphalerite from quartz was chosen, using ammonium di-(sec-butyl) dithiophosphate as. the collector, sodium cyanide as depressant for sphalerite, and copper sulphate as an activator for sphalerite. While the selective flotation of galena and sphalerite using a single dithiophosphate collector is not typical of flotation practice (two different collectors are generally used), it was found that a reasonably good separation could be obtained by using zinc sulphate with the sodium cyanide in the galena flotation and by cleaning the sphalerite concentrate or by carrying out the sphalerite. flotation in an alkaline medium. Data of practical importance on the distribution of collector between the concentrates, tailings, and solutions were obtained, particularly with regard to the effect of copper sulphate and sodium cyanide. In addition to the. selective flotation of galena and sphalerite from quartz, single flotations of galena-quartz and sphalerite-quartz mixtures were carried out, along with blank flotations on quartz alone. The present paper describes the results of these experiments. As in previous papers, the term sorption is used to designate uptake of collector by the mineral, without implication as to the nature of the processes involved. Experimental Materials: The mineral system was a ground synthetic mixture of galena, sphalerite, and quartz. The galena was from Galena, Kans., and contained 75 pct lead (theoretical 85.6 pct Pb for PbS); the sphalerite, from Ottowa County, Okla., contained 63 pct zinc (theoretical 67.2 pet Zn for ZnS) ; and the quartz from Klondike, Mo., analyzed as 99.97 pet SiO2. Sulphur labeled radioactive di-(sec-butyl) dithiophosphate was prepared from S82 supplied by the Oak Ridge National Laboratory on allocation from the U. S. Atomic Energy Commission. The synthesis consisted of precipitating barium sulphate, reducing the barium sulphate to barium sulphide, acidifying to form hydrogen sulphide, and oxidizing the hydrogen sulphide with iodine to elemental sulphur.

Jan 1, 1952

By Martin C. Kuhn, Lawrence G. Stevens, J. Mark Richardson

The majority of the world&apos;s known and anticipated reserves of nickel ores are lateritic deposits At present, there are several different process alternatives for recovering nickel and other desired metal values from laterite ores An overview is given of the selective reduction roast/ammoniacal leach process, one of the processes in commercial operation.

Jan 1, 1981

By W. F. Schwedes, S. S. Rumsey

In order to realize the enconomics which would result in operating the mine pumps at the Chapin mine with electricity generated by water power, the Oliver Iron Mining Co. recently installed a hydro-electric plant at the upper Quinnesec Falls on the Menominee river, and constructed a transmission line to the mine.

Jan 1, 1915

By C. Michael Dickinson

In support of the DNA Deep Basing Program, SRI International has been performing scale model experiments on protective structures since 1973. The SRI program includes field and laboratory tests of mini- structure models with surrounding natural or simulated geology. This paper contains a synopsis of some of the results of this research.

Jan 1, 1984

W. M. Courtis, Detroit, Mich.: Except for free-gold ores, I have always believed in scorification. I think the crucibleassay gives silver low. We found this out at the Wyandotte works in assaying Silver Islet ore. The mine-managers made us, and also the check-assayera, run one of the duplicates by

Jan 1, 1896