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By Abbas Ali Daneshy

A study of the mechanics of hydraulic fracturing shows the fracture initiation pressure to be a function of the in-situ principal stresses, the formation and fluid properties, and how the wellbore has been completed. The orientation of the hydraulic fracture is perpendicular to the least in-situ principal stress. The geometry of the induced fracture depends on the treatment fluid properties, the injection rate and volume, fluid leak-off and formation properties.

Jan 1, 1974

By R. Schuhmann, J. Th. Overbeek, P. L. De Bruyn

THE technique of concentrating valuable minerals from lean ores by flotation depends upon the creation of a finite contact angle at the three-phase contact, mineral-water-air. If the mineral is completely wetted by the water phase, contact angle zero, there is no tendency for air bubbles to attach themselves to the mineral. However, when the contact angle is finite, the surface free energy of the system, water-air bubble-mineral particle, can be diminished by contact between the bubble and the particle, and if not too heavy the mineral will be levitated in the froth. With a few exceptions, all clean minerals are completely wetted by pure water. Thus the art of flotation consists in adding substances to the water to make a finite contact angle with the mineral to be floated, but to leave the other minerals with a zero contact angle. The contact angle concept and experimental measurements of contact angles have played important roles in flotation research for several decades.'-" Nevertheless, there remain unanswered some basic questions as to the scientific significance of the contact angle and the nature of the processes by which flotation reagents affect contact angles. The contact angle is a complex quantity because the properties of three different phases, or rather of three different interfaces, control its magnitude. Considering the interfaces close to the region of ternary contact to be plane, the relation among the contact angle and the three binary interfacial tensions is easily derived. The condition for equilibrium among the three surface tensions, Fig. 1, or the requirement of minimum total surface free energy leads to Young's equation, Eq. I: ysa — ysl = yLA cos 0 [1] According to this equation, the contact angle has one well-defined value. Actually it is found in many experiments that the value of the contact angle depends on whether the air is replacing liquid over the solid (receding angle) or the liquid is replacing air (advancing angle). The receding angle is always the smaller of the two.4 Two explanations have been offered for this experimental fact. According to some investigators,5-8 roughness of the surface causes apparent contact angles that are different for the receding and the advancing cases although the actual local contact angle may be completely determined by Eq. 1. The other explanation involves the hypothesis that the solid-air interface after the liquid has just receded is different from the same interface when no liquid has previously covered it.1,4 Adsorption of constituents of the air or liquid might play a role here. In this discussion the difference between advancing and receding contact angle will be neglected and plane surfaces where Eq. 1 describes the situation will be considered. But there is still a fundamental obstacle to the application of Young's equation. The surface tension of the liquid (rla) can easily be determined, but the two surface tensions of the solid (rsa and ySL) cannot be measured directly. Eq. 1, however, is not without value. By contact angle measurements it is possible to establish how ysl — ysl varies with the addition of solutes to the liquid phase. Also, Eq. 1 affords a convenient starting point for calculating net forces and energy changes involved in the process of bubble-particle attachment.1,2 . If for the moment surface tension of the liquid (yLa) is considered a constant, an increase in ysa — ysL, will tend to decrease the contact angle. A decrease in ySA — ysl, corresponds to an increase of the contact angle. In cases where ySA — ySL > yLa the contact angle is zero; it will only reach finite values when ysa — ysa has been decreased below YLA. Thus on the basis of Young's equation and contact angle measurements alone, it can be learned how flotation reagents affect the difference Ysa — ysl, but no conclusions can be drawn as to the effects of reagents on the individual surface tensions ysa, and ysL, not even as to signs or directions of the surface tension changes resulting from reagent additions. A quantitative relationship between the surface tension or interfacial tension and the adsorption occurring at a surface or an interface is given by the Gibbs equation, which for constant temperature and pressure reads dy = — 2 T, du, [2] where dy is the infinitesimal change in surface tension accompanying a change in chemical potential

Jan 1, 1955

By J. E. Hawley

"The property of Francoeur Gold Mines, Limited, lies directly west of the Armfield mine in Beauchastel township, Abitibi district, and 12 miles west and slightly south of Noranda. The gold deposits are of particular interest because of their replacement character and close association with fault zones. The property was originally staked in 1923 following the discovery oi a mineralized zone near the eastern boundary. This became No. 1 orebody. Later discoveries in 1936 of No. 2 and No. 3 orebodies led to underground development and actual mining in July, 1938. A fourth orebody, No. 8, was found in 1939.The following is the production record up to December 31st, 1947:Beginning in September, 1944, ore was shipped to Noranda as siliceous flux, but late in 1946 milling of low-silica ore from No. 1 orebody was undertaken until operations were temporarily suspended in 1947.The four main ore deposits, Nos. 1, 2, 3, and 8, consist of siliceous ferrocarbonate and albite replacement bodies mineralized with fine pyrite and specularite in schistose fault zones in Keewatin volcanics. Barren to low grade quartz veins though present in some are uncommon, but small stringers of quartz are usually present wherever here and there visible gold is found. Nos. 1, 2, and 3 deposits lie in a major fault zone that extends completely across the property from west to east (over 7,000 feet) and dips N.40° to 50°, and are separated by intervals of 1,800 to 2,000 feet respectively. The fourth lies in a smaller fault zone striking east and dipping on the average 65°S.No. 1 orebody has been explored by mining to a depth of 500 feet, No. 2 to 400 feet, and No. 3 to slightly less than 300 feet . The greater part of No. 8 lies above a depth of 200 feet, but a raise has recently .been driven through from the west end of the 5th level of No. 1 to the 2nd level on No. 8 zone. Most of the ore of No. 8 zone above the 2nd level and of Nos. 2 and 3 above the 3rd levels has been removed."

Jan 1, 1954

By D. A. Karvonen

Although the economy in the Province of Saskatchewan has historically been agriculturally oriented, a major new source of wealth has been realized through natural resources such as petroleum and natural gas, coal and uranium and since the 1960's - potash. Potash or potassium chloride, in the form in which it is presently produced in Saskatchewan is used primarily as fertilizer, a source of potassium, one of three essential elements required for healthy plant growth with about 5 percent of production sold to the chemical industry for use in such products as soap and liquid detergent, glass and ceramics, textiles and some pharmaceuticals. Saskatchewan is estimated to have approximately 40 percent of known world potash reserves and its ten active mines account for some 25% of annual world production. The development of this resource was recognized to be important to the development of Saskathcewan. In an effort to guarantee a fair and lasting economic benefit to the Province of Saskatchewan the Potash Corporation of Saskatchewan (PCS) was created on February 4, 1975 through an Order-in-Council under the Crown Corporation's Act and later on April 1, 1976, the Potash Corporation Act provided for its continuation. PCS was given the mandate to acquire ownership of a significant portion of the potash mining capacity in Saskatchewan and to establish an organization capable of operating the facilities, marketing the product and conducting all of the other activities necessary for a successful corporation competing in the world potash industry.

Jan 1, 1983

By Russell E. Clemons

Coarse-crystalline granite, quartz syenite, syenite, meladiorite, and anorthosite in the Florida Mountains, southeast of Deming, New Mexico, were originally mapped as Precambrian. They were remapped in 1971 and some of them described as Mesozoic intrusives. Several subsequent papers presented Precambrian and Ordovician ages. Zinc, lead, copper, silver, gold, manganese, fluorite, and barite mineralization in the Florida Mountains invite more extensive exploration. Clarification of ages of rocks and periods of alteration and mineralization are necessary for efficient exploration. Field observations combined with petrographic studies strongly suggest that all the coarse plutonic rocks are Precambrian and most were altered extensively by late Tertiary hydrothermal activity.

Jan 1, 1982

By C. G. Albert

The clay particles of 2 microns or less required for modern paper coating are predominantly flat plates, lying smoothly on the sheet and producing a high gloss. Operating speeds of today's coating machines necessitate a clay composition of 60 and sometimes 70 pct solids as against the 35 to 40 pct required in the past. Since clays in suspension may solidify in flow, only those of intrinsically low viscosity can be used as high coating solids. THE literature of paper technology contains a number of articles having reference to developments in the field of coating and filler clays for use in paper manufacture. Much of this information has not been included in mining publications and has therefore not been readily available to all in the mineral industry. Recent developments in this field, including spray drying of clays, are presented here. U. S. Bureau of Mines figures for 1952 indicate that the paper industry consumes more than 50 pct of all kaolin produced and sold in the U. S. As most of the kaolin used by the industry comes from Georgia producers, the fraction of their output destined for paper use is thus appreciably higher than 50 pct. Small wonder that the kaolin industry, especially in Georgia, is highly sensitive to the quality requirements of paper mills and must respond promptly to technological developments in paper manufacturing. The paper industry itself is not the ultimate consumer. For the greater portion of the clay the end product is the printed page, and the demands of printing and publishing have sparked some of the technological advances in paper making which have, in turn, brought about methods employed in the kaolin industry. As compared with the product of 20 or 25 years ago, one of the most striking characteristics of the graphic arts today is the mass production of quality printing of fine pictorial work, much of it in full color. During this time periodicals with printing standards close to those of yesterday's slick-paper publications that were printed on a slow schedule and for a limited circulation have grown to the point where they go out to many millions of readers, often at weekly intervals. The complexity of technological improvements brought about by this increased circulation is probably not appreciated even by technical people, unless they have had reasonably close contact with the industry. The advance has come about through developments not only in the art of printing, but also in the field of paper making and even at the level of clay mining and processing. The smoothness required for faithful reproduction of the kind of printed matter under consideration is attained with a clay-coated paper. Since the distribution expense of the publication will depend to a great extent on its weight, the paper used must not be too heavy. This means a lower basis weight than was normal for conventional clay-coated papers some 25 years ago. And for this mass production market it becomes necessary to provide a paper having these and all the other required characteristics at a very moderate price—not the premium price conventional clay-coated papers formerly demanded. This challenge has been met by a new method of producing coated paper. In the past, application of clay coating to paper was a conversion operation, performed separately from the making of the base sheet. The newer development is called machine coating. Here application of the coating is an integral step in a continuous process by which wood pulp, clay, and other ingredients are manufactured into a sheet of coated paper. Many more problems are involved in this procedural change than are apparent at a casual glance. The coating operation, for example, must function at much higher linear speed than could be obtained with coating mechanisms previously employed. The application machinery developed to meet this requirement necessitated changes in composition of the coating color.* This created new requirements, summarized below, for the clay employed as coating pigment. In addition to smoothness, a relatively glossy printing surface is needed, and to a large measure it is the function of the coating clay to make possible the development of both these surface characteristics. Traditionally, pigments such as satin-white, prepared by reacting lime with paper-makers' alum, were used to assist in producing a high finish. However, economic considerations and others preclude large-scale use of such material in the new processes. In the 1930's Maloney' discovered that a certain particle size fraction of kaolin, consisting

Jan 1, 1956

By H. S. Kalman

A table of factors, for rapid, accurate calculation of the volume of pure helium in cylindrical steel containers, is presented. By use of the table the volume of helium in a container, at base conditions of 14.7 psia and 70° F, can be calculated from the observed pressure and temperature of the helium and the known internal volume of the container. The table covers a pressure range from a to 4,500 psia in 10 psi increments and a temperature range of 0° to 120° F in 2° increments. The calculation of volume requires a single multiplication, using a factor from the table and the known internal volume of the container. A discussion and evaluation of the accuracy obtainable and a derivation of the formula used (which takes into account compressibility of helium, thermal expansion of steel containers, and the stretch of steel due to internal pressure) are presented. An example showing how the table can be used is given also.

Jan 1, 1963

By T. K. McMahon

Formally, a mathematical model could be defined as: A set of equations whose solution will approximate the response of a physical process or system to a set of stimuli which appear as parameters in the equations. The purpose of a mathematical model is to permit the rationalization of experience to proceed by simulation rather than by physical experimentation. In the application of digital computer control to an industrial process, the mathematical model of the process (subsequently called the process model) is needed to calculate the present process performance from the measured variables and to predict the response of the process to a control change. Functionally, the cardinal element in process model development is a concise set of control objectives. These, besides implicitly defining the boundaries of the system to be modeled, will determine the accuracy demanded of the model its nature: dynamic or steady-state, and so forth, The objectives should explicitly define what process efficiencies, production rates, qualities are to lie within the scope of the computer control project, thereby providing a basis for simplifying assumptions in the development of the model. This requirement, a limited set of control objectives, is so often disregarded in formulating industrial control problems that its repetition can scarcely be avoided.

Jan 1, 1965

Tellurium (Te) is one of the least abundant elements in the crust and tends to form minerals associated with copper, lead, zinc and iron sulfide deposits. Today, most tellurium production comes from the anode slimes and other wastes generated in metal refining. Most of the current tellurium produced in the world is used as an alloying agent in iron and steel, as catalysts, and in the chemical industry. However, future demand and production could increase because tellurium is increasingly used in solar panels and some electronic devices. Tellurium minerals are found in Au-Ag districts in New Mexico, but were not considered important exploration targets in the past. In New Mexico, tellurium is found associated with porphyry copper deposits in southwestern New Mexico and with Au-Ag veins in the Eureka, Sylvanite, Organ, Lordsburg, Steeple Rock, Wilcox, Mogollon, Chloride, Cuchillo, Hillsboro, Zuni Mountains, White Oaks, and Nogal-Bonito districts. The only tellurium production from New Mexico has been from the Lone Pine deposit (Wilcox district), where approximately 5 tons of tellurium ore was produced. Gold-tellurides are found with gold, silver, pyrite, and fluorite in fracture-filling veins in rhyolite at Lone Pine, with reported assays as much as 5,000 ppm Te. Other districts in New Mexico have potential for tellurium, but require field evaluation.

Feb 27, 2013

The Wild Dog gold-silver-copper deposit represents a new ore-deposit type in Papua New Guinea. The telluride vein mineralisation is associated with a Tertiary caldera and has similarities with that from the Baguio district, Philippines, Vatakoula, Fiji, and the San Juan Mountains, southwestern Colorado. The deposit, discovered in July 1983, has negligible stream silt and concentrate anomaly, and a float-train limited to within 300m of the prospect. The comparatively recent exposure of the vein system may explain the limited stream expression of the deposit. At least three major veins occur in the deposit; the vein system strikes north- northeasterly, dips 78¦W, and has a maximum strike length of 1350m. Veins are enveloped by a wallrock dominated by an assemblage of quartz-illite-pyrite. Four types of silicification related to multiple vein filling events have been defined on the basis of field relationships, drill-core intersections, petrology and fluid inclusion study. To December 1986 a total of 22 diamond drill holes (2304m) and 40 reverse circulation drill holes (1833m) have been completed on the deposit, defining a 750m zone of interest. The upper 30m of the deposit is oxidised. Much of the high-grade mineralisation in both the sulphide and oxide portions of the deposit is restricted to ore- shoots which strike parallel to the overall vein structure and are vertical to steeply westward dipping. They are defined geochemically by the lg/t Au cutoff and geologically by the relative increase in the vein density of auriferous grey-black sulphidic silica, the final vein filling event. Metallurgical studies and the results of close-spaced drilling have demonstrated the very good repeatibility on duplicate assays, and the extremes of grade variability of mineralisation over very short distances. The good assay agreement on duplicate samples .s indicative of fine, dispersed gold.

Jan 1, 1987

By Nelson Severinghaus

Following the end of hostilities of World War 11, a resurgence of industrial and home building has given impetus to the use of many products of the stone industry. Shortage and high prices of some building materials such as lumber have aided wider acceptance of materials such as concrete products which have been relatively plentiful and which have not risen so rapidly in price. Ingredients for many of these substituting materials come from the stone industries, often from by-products of stone operations. Most of the tonnage of the stone industry in the State of Georgia comes from granite and marble. There are extensive dimension stone operations in granite in the Elberton and in the Lithonia areas. Building and monumental marble from the Tate area has been used throughout the country. Cutting operations in both types of stone have their by-products in faulty blocks and in spalls. In the State there are three large crushed-stone plants utilizing granite, One near Camak, One near Lithonia and one at Stockbridge. All have had excess fines Or in in the past but this excess is largely disappearing with development of new uses. At times this "waste" has amounted to as much as 20 pct of the stone quarried. Handling Of this large tonnage from point of screening out to storage piles presented a costly problem and large areas were taken up by the piles. Crushed 'tone is generally sold with a a narrow margin Of price over cost, so any elimination of disposal cost or increase of income by marketing of by-products is highly desirable. By-products of Granite Dimension Stone It sometimes becomes difficult to differentiate between main product and byproduct. In the cutting of granite dimension stone in the Lithonia district of Georgia, a considerable quantity of remnants of Uneven shape and size is produced. The larger of these pieces have long found use as building rubble, particularly for retaining walls and building foundations (Fig I), They are broken down to one man size by plug drilling and wedging and by hammer. In recent times, demand for this former by-product has grown so that quarries have been opened for the production of rubble as a main product. Local masons have attained skill in using these irregular shapes to form economical and attractive walls. Areas such as Elberton, Georgia, which do not have a large building market nearby, tend to accumulate piles of large pieces of reject stone. When a road job or other local construction offers a quantity market for crushed stone, a portable crusher works this material down to crushed aggregate. Spalls and finer chips from granite stone-cutting operations have generally found their way into crushers and thence to the many uses for crushed aggregate. One company near Lithonia started marketing the smaller by-product crushed sizes for chicken grit about ten years ago. This use has grown to nation-wide distribution and the tonnage is now so great that they have opened a large quarry with

Jan 1, 1948

By Nelson Severinghaus

Following the end of hostilities of World War 11, a resurgence of industrial and home building has given impetus to the use of many products of the stone industry. Shortage and high prices of some building materials such as lumber have aided wider acceptance of materials such as concrete products which have been relatively plentiful and which have not risen so rapidly in price. Ingredients for many of these substituting materials come from the stone industries, often from by-products of stone operations. Most of the tonnage of the stone industry in the State of Georgia comes from granite and marble. There are extensive dimension stone operations in granite in the Elberton and in the Lithonia areas. Building and monumental marble from the Tate area has been used throughout the country. Cutting operations in both types of stone have their by-products in faulty blocks and in spalls. In the State there are three large crushed-stone plants utilizing granite, One near Camak, One near Lithonia and one at Stockbridge. All have had excess fines Or in in the past but this excess is largely disappearing with development of new uses. At times this "waste" has amounted to as much as 20 pct of the stone quarried. Handling Of this large tonnage from point of screening out to storage piles presented a costly problem and large areas were taken up by the piles. Crushed 'tone is generally sold with a a narrow margin Of price over cost, so any elimination of disposal cost or increase of income by marketing of by-products is highly desirable. By-products of Granite Dimension Stone It sometimes becomes difficult to differentiate between main product and byproduct. In the cutting of granite dimension stone in the Lithonia district of Georgia, a considerable quantity of remnants of Uneven shape and size is produced. The larger of these pieces have long found use as building rubble, particularly for retaining walls and building foundations (Fig I), They are broken down to one man size by plug drilling and wedging and by hammer. In recent times, demand for this former by-product has grown so that quarries have been opened for the production of rubble as a main product. Local masons have attained skill in using these irregular shapes to form economical and attractive walls. Areas such as Elberton, Georgia, which do not have a large building market nearby, tend to accumulate piles of large pieces of reject stone. When a road job or other local construction offers a quantity market for crushed stone, a portable crusher works this material down to crushed aggregate. Spalls and finer chips from granite stone-cutting operations have generally found their way into crushers and thence to the many uses for crushed aggregate. One company near Lithonia started marketing the smaller by-product crushed sizes for chicken grit about ten years ago. This use has grown to nation-wide distribution and the tonnage is now so great that they have opened a large quarry with

Jan 1, 1948

By Ben H. Daud

The systems optimization approach to mine planning has led to the adoption of a number of mathematical and computer models for short, medium and long range planning of mining operations. In the realm of open pit mine planning, the most common uses of such an approach have been in the areas of optimal pit design and planning of materials handling operations. Since a truck-shovel combination is the most widely used method of materials handling in open pit mines, a number of models have been presented in the past to analyze and optimize such systems. Broadly, these models can be divided into two categories. The simulation model, which is primarily used as an aid in analyzing the performance of either an operating or a proposed haulage system under the influence of externally alterable parameters, and the linear or integer model which is used as a tool for short or medium term optimization of the system under the operating constraints. In the first part of this paper, a brief discussion is presented of the linear/integer optimization models presented in the past, and in the second part a new model is described which is actually a combination of the simulation and the integer programming models. In its bare essentials, the model consists of an integer optimization algorithm, but the constraints are regularly and dynamically updated by incorporating the conclusions drawn from a stochastic simulation model of the mine haulage system. Since the successive optimization is performed by the mine operator who manipulates the constraints to guide the model towards the optimum, the mystical black box approach is minimized and should help in adoption of the model by the mine personnel. Also, by combining the stochastic simulation model and the deterministic integer model, some of the advantages of each are acquired.

Jan 1, 1976

Servicing School Opening of a special factory training course in servicing earthmoving equipment is announced by the Euclid Road Machinery Co. Four [ ] beginning and four advanced one week training courses will be offered to representatives of distributors and customers. Circle No. 1 Core Drill The new Acker "Teredo" core drill, is named after the "boringest little animal in the world" to underline its function as a light, compact, portable core drill capable of depths to 600 ft. While light enough to be truck or jeep-mounted, it offers the combination of a three-speed totally enclosed transmission with either hydraulic or screw feed drill heads. Full 24-in. travel gives maximum footage per shift, 360° rotation permits freedom of hole location, a transmission mounted cathead winch is used in pulling rods and casings, and a power take-off is provided for a pump. Circle No. 2 Plastic Pipe Planned production of both flexible and semi-rigid plastic pipe is announced by Triangle Conduit & Cable Co. Rigid and high-impact pipe will be added to the line later. Three types: non-toxic, industrial, and suction, are being made and in sizes from 1/2 to 6 in. Circle No. 3

Jan 1, 1952

By P. L. De Bruyn

The behavior of collectors at the mineral-solution interfaces is usually explained in terms of an ionic adsorption process. Through the distribution of collector ions between the solid surface and the co-existing solution phase the mineral is believed to acquire a water-repellent surface coating. Quantitative adsorption studies have been made on simple flotation systems only within the last few years. Such investigations were made possible by the adoption of the radiotracer method of analysis. As a consequence of these studies a new parameter has been added to aid the understanding of the flotation process.

Jan 3, 1955

By Lloyd A. Morley, Robert Stefanko

In the context of the following report, an hazardous location can be described as any industrial area in/which flammable or explosive gases, vapors, and dusts can be encountered. When electrical apparatus is used in such hazardous atmospheres, the chance of a dust or gas ignition is ever present. Consequently, in an effort to reduce the ignition hazard, several protection systems have been devised. Such systems are termed electrical hazard reduction techniques. The most widely accepted and used of these, the explosion-proof enclosure, is the principal subject of this report. However, other techniques are briefly mentioned. Hazard reduction techniques used in coal mine atmospheres (which can contain methane, coal dust, and air mixtures) are classified as Group I. The explosion-proof enclosure commonly used in mines is defined by the USBM Schedule 2G as a device that can contain internal explosions of methane-air mixtures without undergoing damage or excessive distortion and without an ignition of a surrounding methane-air mixture or discharge of flame. (100) Internationally, the definition remains the same except the words "discharge of flame" are not present. (4,5,31,42,52,76,102) The latter description often refers to flame-roof enclosure construction, but the terms "flameproof: and "explosion-proof" commonly have the same connotation. These enclosures which may not be vapor tight, are distinguished by heavy-wall cast or welded construction and bolted or threaded close fitting flanges. Explosion-proof enclosure techniques have been utilized in U.S.

Jan 1, 1974

By M. K. Gangal, E. D. Dainty

CANMET/MRL has been contributing to an industry/government program to assess the quality of air in mines, and improve the working environment for Canadian miners. The ultimate aim of this program is to recommend a sampling methodology and appropriate concentration limits for both the soot (diesel particulate matter - DPM) generated by diesel equipment, and respirable combustible dust (RCD) as measured underground. The program was conceived by the Canadian Adhoc Diesel Committee, which consists of representatives from seven major Canadian mining companies, three provincial inspectorates, one union representative, two manufacturers of diesel equipment, and CANMET, a Federal Canadian research agency. This paper describes the modification and laboratory confirmation of an existing methodology for the sampling and analysis of DPM/RCD, including: sampling problems, filter selection, filter efficiency, DPM size distribution, the approximate performance of fractionating devices, and it reports the results of current ambient measurements of exposure levels in Canadian underground mines. Because of the concern about the health impact of DPM/RCD on mine workers, North American agencies are in the process of establishing limits for these aerosols. So far, the Province of British Columbia is the only jurisdiction in North America to legislate the maximum exposure level of RCD in its underground mines, i.e. 1.5 mg/m3 interim level recommended by the Adhoc Diesel Committee. It has also recommended the use of the CANMET/ADHOC RCD sampling protocol.

Jan 1, 1993

By Wm. F. Wuest

INTRODUCTION THE Western Canada sedimentary basin has one feature in common with the Precambrian Shield area: it also was a great chemical laboratory. The mining industry of Canada exploits the end products of chemical experiments that occurred on the Shield during periods of repeated disturbances in Precambrian times. The petroleum industry on the other band exploits what also appears to be the final results of chemical experiments that took place throughout all of post-Precambrian up to Tertiary times. Since the subject of this paper is a factual study of Alberta well waters, no attempt is made to answer significant questions pertaining to the probable role waters play in the generation of oil, or to the significance of the effects of structure and depth on waters. Data from several hundred well-water analyses were compiled by the writer in a series of charts and diagrams, of which those included in this paper are representative. Early studies indicated the possibility that outstanding anomalies in general concentration of waters and in greatly increased concentration of elements such as calcium, magnesium, bromine, and iodine for example, might be expected from wells that produced oil or were in the immediate vicinity of producers. The water analyses from wells which? were drilled at a later date did not confirm this possibility, and it is suggested that, aside from their initial value to the petroleum engineer or to. those interested in the commercial possibilities of brines, no definite significance as an aid in oil discovery can be attributed to water analyses.

Jan 1, 1951

By Rolf Katzenbach

Construction of drilled shaft foundations with the use of hydraulic oscillators and rotators to install temporary casing over the full depth of the shaft is described. The equipment and techniques were developed in the 1960?s in Germany and full-depth casing is now the predominant method of construction in Europe. Its use in North America is increasing. This paper presents an overview of full-depth casing methods and a summary of available load test data evaluated by the authors to compare the load transfer and capacity performance of shafts installed by various construction methods. Results demonstrate that load transfer and capacity of full-depth casing shafts are equal to or exceed that of shafts constructed by dry or slurry methods and that measured capacities are consistent with generally accepted design equations. The principal advantage of full-depth casing methods over other installation techniques is that the risk of defects in the shaft is minimized. Casing is able to penetrate into the ground under any geologic or groundwater condition when this technique is applied. Potential delays and cost overruns can thus be avoided and a safe, economical foundation element is created.

Jan 1, 2007

By W. T. Hicks

Visual observation of the oxidation of columbium shows that the protective behavior noted previously in gravimetric work in the early stages of the reaction below 600°C and throughout the reaction at 640°C is associated with an adherent oxide. The fact that the oxide is seen to move outward from the metal at temperatures from 550° to 935°C implies that the reaction takes place at the oxide-metal interface throughout this temperature range. THE work described in this paper further clarifies the complex oxidation kinetics of Cb revealed, for example, by the continuous gravimetric studies of T. L. Kolski.1 Time-lapse motion picture studies reveal details of the reaction not provided by a study of the combustion products. EXPERIMENTAL PROCEDURE Cb specimens were prepared from material with the following typical analysis: 0, 0.03 pct; N, 0.002 pct; C, 0.006 pct; Ta, 0.04 pct; Fe, 0.01 pct; Ni <0.003 pct; and Cr <0.003 pct. Arc-cast ingots were swaged and cold rolled into slabs. These slabs were machined into blocks 7/16 by 7/16 by 7/16 in; 1/16-in. holes were drilled through the large face of the blocks for suspension. The samples were then de-greased and annealed 1 hr at 1200°C in vacuum. The sample was suspended by a platinum and Pt 10 pct Rh thermocouple inside a 1-in. quartz tube in a Kanthal wound furnace (2 in. OD by 4 in. long) equipped with windows 1/2 in. sq. A Cine-Kodak Special II 16 mm motion picture camera was trained on the sample through a Spencer microscope adjusted so that a magnification of X1.5 resulted on the film. Super Anscochrome film was used to record the events in color. Argon was flushed through the furnace while the sample came to temperature. The argon was then replaced by a stream of dry oxygen at 1 atm. Pictures were taken at the rate of eight per second for about 20 sec during the change of atmosphere. Then by use of a Stevens time-lapse device pictures were taken at the rate of four per minute starting within 1 min of the initial oxygen flow. In this manner continuous visual records of the oxidation of pure Cb

Jan 1, 1962