Search Documents

By F. H. Edmunds

Introduction This paper, it is hoped, will serve as an introduction to further work upon the origin of the soils and to a more complete interpretation of the geology of Saskatchewan from a study of the soils of the Province. The great difficulty that is encountered in mapping the structure of the prairie regions of the west must be evident to all who have made the attempt. The rarity of good exposures, due to the extensive coverings of glacial drift, is the greatest obstacle, making it difficult to determine the exact stratigraphical position of such exposures as may be found. In many cases palæontological evidence is lacking, or, if available, our present knowledge of the stratigraphy is insufficient to justify division of the formations into horizons; and until many of these formations have been subjected to petrographic investigation, little can be done in using lithological differences as an aid to the correlation of the usually sparse outcrops met with in the Province. Topography may be of the utmost value as an indication of geological structure when considered in conjunction with other evidence. It does not necessarily follow that, because an area in Saskatchewan has resemblances in surface configuration to an area of oil-producing land in Texas, there is sufficient justification for sinking money in wells without further investigation. Such - investigation should include the study of available soil maps.

Jan 1, 1929

By Chas. G. Maier

The bright annealing of copper is an industrial practice of considerable importance. In connection with this process, equilibrium concentrations of carbon monoxide and dioxide, which may exist in contact with copper and cuprous oxide at elevated temperatures, are of interest. Data obtained at the Pacific Experiment Station of the U. S. Bureau of Mines enable estimates of these equilibrium concentrations to be made in two independent ways. Although the publication of final data on one method can not take place until certain further experimental work is accomplished, repeated requests which the Bureau of Minus has had for data relative to the annealing and deoxidation of copper justify the present preliminary report. This paper deals with the calculation of gas concentrations in the reduction of cuprous oxide, using more scientific data which will be published later, and refers especially to those conditions of temperature and concentration of practical implication, and from which critical limits ensue.

Jan 1, 1929

By A. W. Hann

THE importance, to geologists and metallurgists, of knowing the mineralogical forms in which the silver occurs in ores has increased during the past few years, and will continue to increase as long as working hypotheses are converted into proved theories and rule of thumb methods are supplanted by scientific data. The methods used for the determination of these silver minerals have been: (1) careful study of polished ore sections with the microscope, and more recently, (2) metallurgical separation of the ground ore by flotation, tabling and panning, supplemented by microscopic examination of these separated minerals, and chemical analyses. During the course of some experimental work carried on by the testing department of the International Smelting Co. and myself, it became important to determine, in a general way, the distribution of the silver values in the minerals, as they exist in Tintic Standard and North Lilly siliceous oxidized lead-silver ores. These mines are in the East Tintic Mining District, State of Utah. In this work the second method was used. Differential flotation tests were run, separating the sulfide from the oxidized minerals, and the products were assayed. Various concentrates were carefully panned and the separated products assayed; special samples of ore were selected and assayed. The microscope was used only for the purpose of determin; ing whether the individual minerals were in the so-called "free" state. Analysis of Tintic Ores These chemical and mineralogical determinations showed the silver to be present as native silver, argento jarosite, argentite, and combined or inherent in the tetrahedrite, chalcopyrite, galena, pyrite, cerussite, anglesite, mimetite, malachite, iron oxide and occluded in the quartz. Careful microscopic work would probably show other forms in small amounts, such as the halide silver minerals and some of the antimony sulfide combinations. The tabulation of the analyses of the various products (Table 1) shows no evidences of fixed ratios of silver to any particular base metal.

Jan 1, 1929

By Charles Berkey

CONTENTS PAGE C. P. Berkey-Responsibilites of the Geologist in Engineering Projects (with discussion) 4 Kirk Bryan-Problems Involved in the Geologic Examination of Sites for Dams 10 0. E. Meinzer-Relation of Ground-water Conditions to Leakage of Reservoirs (with discussion) 19 Charles Terzaghi-Effect of Miner Geologic Details on the Safety of Dams (with discussion) 31 G. H. Matthes-More and Better Geologic Data for Use in Hydraulic Projects (with discussion) 47 L. W. Fisher and R. D. Ohrenschall-Geologic Examination of Dam Sites in the Tennessee and Cumberland River Basins 60 C. K. Wentworth-The Geology of Dam Sites (with discussion) 78 L. C. Glenn-The Geology of Dams and Reservoirs 97 H. T. Stearns-Success and Failure of Reservoirs in Basalt (abstract) 111

Jan 1, 1929

By G. M. Schwartz

THERE has been considerable controversy regarding the structure and mineral constituents produced when iron ore is sintered. This investigation was undertaken in order to establish the fundamental reactions that take place in the sintering process by determining the nature of the resulting minerals. The writer's immediate interest in the subject arose mainly from the request of E. W. Davis for information based on a microscopic study of sinter submitted by him in May, 1926. In the author's preliminary work, samples of iron-ore sinter were secured from the Minnesota School of Mines Experiment Station and from commercial plants. These were polished by the usual methods for polishing opaque ores. In order to study these surfaces satisfactorily, it is necessary to magnify them rather highly, a range from 100 to 1000 dia. being used. For the higher magnifications oil-immersion lenses and an intense source of light are necessary. After the preliminary study had shown the problems involved, a series of small samples were sintered under carefully controlled conditions and with analyzed materials. Variations in the relative amounts of ore, coal and water were made in order to study the effect of each constituent. The attempt has been to arrive at a clearer understanding of the sintering process and the reactions involved without reference to any preconceived notion as to sinter. It is clear that the study of polished surfaces has yielded results not possible with thin sections alone. The thin sections made in this work were found unsatisfactory at magnification greater than 75, whereas magnifications of 1000 were easily studied with reflected light on carefully polished surfaces. A rather complete statement of observed facts is made so that the reader may form his own conclusions. The writer's interpretations are suggested.

Jan 1, 1929

By O. W. Ellis

THE writer has dealt with the effect of various methods of melting copper upon the gas content of the metal.1 The copper referred to in his in his earlier paper was melted in the foundry both in the oil furnace and the electric furnace. As the metal, did not measure up to conductivity FIG. L -INGOT OF OVERPOLEP COPPER. standard, the term "casting copper" was applied to the material in the title of the paper. It was thought that some information in regard to the gases in a sample of overpoled copper might also be of interest, and through the courtesy of C. R. Stevens, superintendent of the copper mill of the Westinghouse Elec. & Mfg. Co., such a sample was obtained. The metal was chill-cast in the form of an ingot about 7 in. long, 2 ½ in. deep (from the base to the raised surface of the ingot) and from 1 3/8 to 1 7/8 in. wide. A photograph of part of the ingot is shown in Fig. 1. The effect of overpoling on the surface of the metal is here quite clearly shown.

Jan 1, 1929

By Staff

Introduction The Hedley mine, perhaps better known as- the Nickel Plate mine, is one of the outstanding properties of southern British Columbia. Discovered in 1898 by Woollison and Arundell, prospectors, the property was bonded in 1899 to M. K. Rodgers for the Marcus Daly Estate, of Butte, and development was started the same year. From the high grade of the ore outcrop, and its colour, due to oxidation of the arsenopyrite, it was not difficult to open up and trace the showing. The Nickel Plate ore-shoot, which apparently had been easy to follow on surface, was more difficult to trace underground. In 1903, prospecting on an adjoining property, the Sunnyside, showed commercial ore at surface, but it was only after two years' work that the ore-body was defined and shipments started. From this property, $1,200,000 have been taken out. Prospecting was also carried on on the IXL, Climax, Copper Cliff, Mound, Bulldog, Exchange, Silver Plate, Gold Plate, and other properties, all of which had surface showings, but up to date only the Nickel Plate, Iron Duke, Morning, and Sunnyside have produced commercial ore. In 1904, the Bulldog looked like a very promising mine, but it failed to make good. In 1905, the Sunnyside No. 1 was in the limelight, but it also failed to make the grade. In 1906, an outcrop on the Sunnyside No. 3 looked interesting. Subsequent work. on this claim produced $840,000, and at the same time ore which yielded $400,000 was mined from the Sunnyside No. 4. In 1908, the Nickel Plate ore-body entered a lean zone and, as the diamond drill failed to give satisfactory results, the Daly Estate, after making a profit of $1,151,000, sold the property to the Hedley Gold Mining Company, Limited, for $760,000, retaining, however, a large interest.

Jan 1, 1929

By Lancaster Jones

The gravity magnitudes obtained by means of observations with the Eötvös balance in the field are necessarily resultant or total effects due to all abnormalities of mass distribution, including even the effects due to the ellipticity and rotational motion of the whole earth. Since the object of the survey is to isolate the effects which arise solely from some particular subterranean feature, and to deduce therefrom the configuration and extent of this feature, the first step is to eliminate from the observed effects all those due to "disturbing" (i. e., unwanted) features, whether above or below the surface of the ground. The disturbing features have different characteristics, according to their situation relative to the center of the balance and to the horizontal plane through the foot of the balance, or station point; this diversity was recognized by Eotvos, who divided the total effects into so-called Normal, Terrain, Topographical, Cartographical and Subterranean effects. This classification has been adhered to by most subsequent investigators, but the writer prefers to employ the term "three-dimensional," which really indicates the essential character of the class of effect known as "Subterranean," at any rate from the standpoint of the computer of effects. Before disturbing effects can be eliminated, the features must be measured up or surveyed, whether by topographical, mining, or boring methods, and then the effects of each feature calculated and subtracted from the total observed effects. After this the problem of interpreting the residual effects will itself necessitate the computation of the assumed feature, or even a series of trial features. The task of computing gravity effects is therefore of great importance. In the early work, by Eötvös himself, the computation practically ceased when the terrain and topographical effects had been calculated, but later surveys have demanded an ever-increasing extension in the technique of computation. Certainly in surveys designed to locate minerals, particularly ores, the calculations have to be extended far beyond those of Eötvös, while his methods of computing both terrain

Jan 1, 1929

By G. St. J. Perrott

Through the development of manufacturing processes whereby ethylene glycol can be made on a large scale; ethylene glycol dinitrate is now being used in high explosives (dynamites and permissible explosives) by some manufacturers as a low-freezing ingredient of the "explosive oil" instead of such compounds as nitropolyglycerin and nitrosubstitution compounds. The amount of ethylene glycol dinitrate being used constitutes 25 to 50 per cent of the oil. The purpose of this report is to give the results of toots, to determine the effect on the safety and physical properties of permissible explosives of subsituating 25 peg cent of ethylene glycol dinitrate for an equal amount of nitroglycerin or a mixture of nitroglycerin and nitropolglycerin.

Jan 1, 1929

Albin, B. R Billings, Mont. Amster, Nathan L 25 Broad St., New York, N. Y. Bache, Jules S 42 Broadway, New York, N. Y. Barrett, C. P6338 Harper Ave., Chicago, Ill. Baum, Frank G Hobart Bldg., San Francisco, Cal. Bayless, Hon. William S Russ Bldg., San Francisco, Cal. Bean, Louis H., V.P., Dwight P. Robinson & Co., Inc 125 E. 46th St., New York, N. Y. Beatty, Ross J 1106 First National Bank Bldg., Chicago, Ill. Benwell, Oswald F 205 Colorado National Bank, Denver, Colo. Beymer, Albert S., V.P., Keystone National Bank Pittsburgh, Pa. Bingham, Charles W 1542 Hanna Bldg., Cleveland, Ohio. Blumenthal, Hugo 44 Pine St., New York, N. Y. Boettcher, Charles Ideal Cement Bldg., Denver, Colo. Bowlus, Thomas H Iola, Kans. Bragg, E. B Carmel, Cal.

Jan 1, 1929

By P. R., Bradley

THE Juneau gold belt is divided into ore-bands of poor definition. The most easterly workings on the , belt, those of the Alaska Gastineau Co., disclosed three separate bands: the Footwall or Ground-hog band, 70 ft. wide; the Perseverance band on which the recent mining was done, also 70 ft. wide; and the No. 2 band, 100 ft. wide. These bands, aggregating 240 ft., are found over a width of 2000 ft. Going toward the west into the adjoining Alaska Juneau ground, four bands have been found which have a total 'right-angle thickness of 755 ft. These bands are convergent in their westerly trend and terminate on the plane of Silver Bow fault. The four bands have better definition at the fault plane than at the eastern boundary line where they enter the property. -Along the property line, the width of the bands and intervening country is 1600 ft., and at the Silver Bow fault this width is reduced to 1300 ft. The distance from the eastern property line to Silver Bow fault is 2400 ft. The bands are slate or slate with metagabbro intrusions, together with gold-bearing quartz masses, stringers, and gash veins. The bands themselves are not all ore, but all commercial .ore is found within the bands. They have no uniform width either in horizontal or vertical section. The ore has no hard and fast boundary except where cut by faults, and profitable mining ceases on a vague and

Jan 1, 1929

By R. S. Cartwright

TWO types of automatic drilling controls, the Halliburton and the Hild, are now available and are coming into more or less general use in deep drilling. The primary function of both is to maintain a safe limit of torque on the drill pipe, this being accomplished by automatically controlling the weight or pressure on the cutting tool. Neither type will necessarily increase drilling speed, but by permitting advantage to be taken of "breaks" in the hole higher average cutting speed may be maintained. The control is essentially a safety device, and should be considered as such. It is not the purpose of this paper to discuss the merits of drilling controls, although the advantages over manual feed at the brake drum are obvious, but rather to point out some of the limitations. The Halliburton Control The Halliburton control is designed to operate during drilling through the agency of the draw works. Automatic and constant control of the torque on the bit is governed by clutches on the control itself, and the line shaft to drum shaft drives on the draw works. In operations other than drilling the control is simply a jackshaft between prime mover and draw works. It is, of course, adaptable to any type of power. Because control of the torque on the bit is dependent on the various ratios or clutch combinations available on the Halliburton control and the draw works, it follows that there are certain limitations in points of control. Table 1 shows the possible ratios which can be obtained with the control and a popular type of three-speed draw works, it being assumed that the highest possible gear combination—the combination which when engaged will suspend the least amount of weight—has a value of 1.00. According to the table there are "blind spots" in the series. This is true particularly among the lowest ratios, which are most used to suspend the major part of the weight when great depths are reached. It will be noted that there is a difference of nearly three units in the value of the

Jan 1, 1929

By Philip Morse

THE Australian lead-smelting plants began to use charges carrying high zinc percentages somewhat earlier than was common with American plants. When lead smelting first started in Australia the immense deposits of oxidized lead at Broken Hill were available but later these oxidized ores became exhausted and were replaced by sulfides. This was before the days of flotation and these sulfides when concentrated carried about 1 per cent. of zinc to 6 per cent. of lead. The works of the Sulphide Corpn. at Cockle Creek was perhaps the pioneer in high-zinc slags but the Port Pirie plant of the Proprietary Co. was a close and very able second and has continued the work to the present time. The Cockle Creek lead furnaces remained in operation until shortly after the war when most of the Broken Hill companies combined and took over the Port Pirie plant to treat their concentrates. As it was the practice both at Cockle Creek and Port Pirie to carry 20 per cent. or more of lead on the charge, it was found that under these conditions of large amounts of zinc in the charge, good roasting was absolutely necessary and matte production was unwise. The Huntington-Heberlein system of roasting was introduced and later the Dwight & Lloyd process. In this way, by roasting the sulfide portions of the charge as thoroughly as possible and making no matte, a method of smelting was developed where the slag over long periods carried as high as 20 per cent. ZnO without serious furnace troubles, and slags carrying even up to 33 per cent. ZnO have been reported. The zinc slags were not very different in appearance from the ordinary slags produced in American practice except that they gave off more smoke and fume on tapping. The slag usually ran hot and freely, coming from the tap in a full stream. Normally there was little crust on the sides' of the furnace and the tuyeres gave no trouble though they were always rather dark.

Jan 1, 1929

By S. P. Kinney

The efficient operation of a blast furnace is primarily dependent upon efficient contact between the descending stream of solid materials and the ascending stream of gas. The United States Bureau of dines is conducting a program of research dealing with the interior of the present-day furnace. The work is being carried oat by.(1) observations on commercial furnaces end (2) experiments in the laboratory. Through the courtesy of the officials of the Illinois Steel Co. it was possible to make a detailed investigation of the interior of the shaft of Number.4 furnace at the company's South Works, South Chicago, Ill. The experimental work is to be reported in a U. S. Bureau of Mines bulletin which will include the results of several thousand observations on the interior of the shaft of this furnace. Such of the data as are presented later in this paper constitute only a brief summary.

Jan 1, 1929

A complete list of permissible mining equipment, rescue apparatus and gas masks tested. Prior to Jan. 1, 1929, w s published in Bureau of mines Information Circular 60972. The present list includes practically all equipment tested and. approved by the Bureau, up to and including July 1, 1929. It covers electric air compressors, coal drills, mining machines, loading machines, conveyors, mine pumps, room hoists,, mine telephones, rock-dusting machines, switches, electric cap lamps, flame safety lamps, electric hand and trip lamps, flash lamps, methane indicators and detectors, blasting units, storage battery locomotives, tandem locomotives, power trucks, concrete mixers, self-contained oxygen breathing apparatus and gas masks. The system under which these devices were tested permits the manufacturer, after his equipment has passed certain tests prescribed by the Bureau of Mines, to mark his equipment with a seal showing hat it has been "approved" by the Bureau. These tests are designs to insure that the equipment has the minimum requirements for safety in use. The only object of the Bureau in making such tests and publishing lists of permissible equipment is to safeguard the lives of workers and to help lessen the hazards of mining.

Jan 1, 1929

By H. M. St. John

LIKE every present-day manufacturer, the brass foundryman is faced with the necessity of reducing the cost of his finished product without impairing its appearance or quality. He must use every economy that the progress of art and science puts at his disposal and should also be alert to profit by any peculiarity in his own situation or the nature of his product that may give him an exceptional advantage. Much can be accomplished by the adoption of labor-saving equipment and improved methods of melting, molding and handling. Control of pouring temperature, study of defective castings and their causes, laboratory control of molding sand and core mixtures, the use of less expensive alloys, all contribute to the desired end. Assuming that the composition of the alloy is already as inexpensive as the character of the casting will permit, still further savings can be made by the intelligent purchase and utilization of the metals needed to produce the desired analysis.

Jan 1, 1929

By C. F. Jackson

This paper describing the mining practices at a mine in the Southeast Missouri district is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The conditions, operating methods, and practice described in the following pages arc those obtaining at a property in the Southeastern Missouri lead belt, St. Francois County, Mo. This property is the eldest in the county and is a consolidation of a number of separate mines originally opened up as individual operations many years ago. Present-day operations have necessarily to be adapted to suit the older levels, stones, and pillars, and also the recovery of ore from worked over areas which was considered too low grade to mine in the earlier days constitutes a different problem than that of development and mining in virgin ground.

Jan 1, 1929

By W. G. Wender

This report covers the area producing from limes and sands of Pennsylvanian age, roughly embracing the territory between the Red River on the north and the Llano Mountains on the south, and between Fort Worth on the east and Abilene on the west. It includes Archer, Cooke, Montague, Wichita, Wilbarger, Clay, Baylor and Foard counties in the North Central Texas or Red River Basin area, and Brown, Callahan Coleman, Comanche, Eastland, Erath, Palo Pinto, Stephens, Shackel-ford, Throckmorton, Young and Jack counties in the West Central Texas area. Furthermore, it includes a brief review of development in Jones, Runnels, Haskell and Fisher counties. North Central and West Central Texas during the year 1928 produced an approximate total of 50,948,7461 bbl. or oil. This represents a decrease of approximately 7,720,250 bbl. under 1927 total production. This decrease was due to a slump in production in Brown, Archer, Wichita, Stephens and Cooke counties. Brown County showed the greatest decrease. The 1928 prodction in this county was approximately 4,500,000 bbl. less than the 1927 production. Gross production during 1929 in the North and West Central Texas area can be expected to be lower than in the year 1928. Only one county showed a considerable increase in production. Wilbarger County production increased approximately 3,000,000 bbl. during 1928. Its daily average increased from 9000 bbl. in April to 36,000 bbl. in August. At the close of 1928 it was averaging close to 32,000 bbl. daily. Drilling activity in North and West Central Texas during 1928 showed but a slight increase in completions. The total number of completions during 1928 was 3902, of which 2094 (53 per cent.) were producers, as compared to 3805 completions and 2112 (56 per cent.) producers during 1927. Brown, Young, Wichita, Archer and Wilbarger counties were the leaders in development. The outstanding discoveries for the districts were the Consolidated pool, extensions in the Greyback pool of Wilbarger County, and the Stephens pool, Fisher County.

Jan 1, 1929

By Oliver Bowels

Many inquiries are received by the United States Bureau of Mines for the names of elementary books on geology, mineralogy, methods of identifying minerals, prospecting, and similar subjects. In response to this demand the following brief bibliography has been prepared. As many of the inquiries are received from those who have limited technical knowledge of the subjects involved, the bibliography includes the simpler texts which present the subjects in nontechnical language. Other texts contain glossaries which define the technical terms used. A short note following the title indicates the character of each book, the number of pages, and the price. Thus, elementary mineralogists or geologists, prospectors, mineral collectors, nature students, or travellers may select the texts that best suit their requirements and their capabilities. To supply the needs of more advanced students, quite a number of the standard texts used in schools and colleges are included in a second group. A short list of books on economic geology and mineralogy has also been added.

Jan 1, 1929

By George Scott

MANY requests for information as to the possibility of washing coals to some predetermined percentage of ash or sulfur have suggested that the producers aim to satisfy some degree of purity set by the user of the fuel, rather than to attain the greatest economic benefit to all concerned. This paper is written to show that the highest economic purity of washed coal can be determined from washability studies of the raw coal, costs of mining and washing coal, and data on the effect of ash and sulfur on the value of the coal for the particular use for which it is intended.

Jan 1, 1929