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By Scott, Turner

MY whole life has been spent in the mining business, PO I naturally tend to address my remarks particularly to the newly-graduated mining and metallurgical engineers among you. To a certain extent, all forms of engineering principles are involved in the training of the mining engineer, and most sorts of engineering are certainly utilized by him, so every one of this graduatins class is concerned with the field I propose to discuss.

Jan 1, 1932

By Paul C. Merritt

The story now unfolding on the Mesabi Range is more than just another chapter in the continuing history of iron mining. It is an epic of foresight, research and pioneering instinct just now culminating in the rapid growth of a new industry hardly more than ten years old. And that growth has been impressive. In the decade that has passed since Reserve Mining Co. blazed a trail as the first successful large- scale commercial taconite operation, the number of plants now existing or soon to be operating has grown to six. From Reserve's initial capacity of 3 million tons of pellets per year, total production capacity on the Range has surged to 31.5 million tons while capital investment has leaped from $300 million in 1955 to almost $1 billion today. During the past year alone, more than $500 million has been committed to these projects, an amount probably greater than that going into any other single mining area in the world. There is more yet to come.

Jan 10, 1965

By AIME AIME

AN enthusiastic crowd, cheerfully confident that the upturn in the oil industry has arrived, gathered in Los Angeles on Sept. 29 for a Petroleum Division meeting arranged by the Southern California Section. The assembly room of the California Oil and Gas Association was the place of meeting. H. Norton Johnson was in the chair for the morning session, with about eighty members and guests present. Four papers were presented before lunch and a fifth, on electrical coring, was withdrawn as the work on which it was based is still confidential. Joseph Jensen read his contribution on the "Kettleman Hills Middle Dome Unit Plan" and, as he had an active part in framing the plan, his outline and discussion of it was authoritative and informing. J. H. Woods asked concerning the operation of the casing-head gasolene plant under the plan and was informed that one company would operate the plant and royalties would be paid participating companies

Jan 1, 1933

By W. S. Tower

STEEL is the basic metal, the main metallic prop of the modern industrial world, a good gage for measuring the state of our complex economy. Any who had doubts on that score should have had them dispelled by the many evidences of public concern over the affairs of the steel industry in recent months. I do not need to relate the various criticisms of the industry, nor the questions about its policies and performance which have come in a rising flood, especially from unthinking and irresponsible sources. But judged from the standpoint of production, or from plans to improve and expand facilities, or from technical progress, the facts about the steel industry are proof of

Jan 1, 1948

By Earle Schumacher

THE solidus line above the solid solution field in the lead-antimony system was originally determined by Dean and his associates1 from heating curves. They did not regard this line as having been accurately fixed and in their more recent publications2 the curves drawn do not follow closely the original data. The precise location of the solidus line is of importance in the extrusion of lead-antimony cable sheath, as the temperature of the metal in this process must be less than the lowest temperature at which any part of the alloy in the lead-press charge becomes liquid. It is very desirable, however, to operate at as high a temperature as possible, as the rate of extrusion for a given pressure is approximately doubled for an increase of 10° C. in temperature. The precise location of this line is also important, in the investigation of ternary systems of lead, antimony and a third metal. For these reasons, and because of the differences reported in the literature, data were secured on the lead-antimony solidus line by the classical quenching-test procedure.

Jan 1, 1927

APPROXIMATELY 26 percent of the total ore production to date from the largest single deposit of copper-bearing material in the world was mined during the war years, 1942 to 1945, at Chile Exporation Company's great open-pit mine at Chuquicamata, Chile. About 18 percent of the total waste removed during the life of the mine was handled in the same period. The total of ore and waste represents approximately 24 percent of the total material that has been excavated from the pit. This is more than was removed in the first fourteen years of operation from 1914 through 1927. The pit at Chuquicamata is 17/8 miles long, 1/2 mile wide, and has a present vertical extent of 817 ft between the top of the highest bench and the lowest bench being worked. However, when

Jan 1, 1948

By Michael Tenenbaum

The importance of semikilled steel as a high tonnage grade has long been recognized. The increasing severity of the applications for which semikilled steel is used makes it desirable to obtain further information regarding the features of open hearth practice and ingot structure that can affect steel performance in subsequent rolling and fabricating operations. Accordingly, an investigation is being carried out studying the structure of various types of semikilled steel ingots. This paper reviews some of the observations made and information gathered in this investigation. By definition, semikilled steel may be considered to include all nonrimming steels in which the natural shrinkage occurring during ingot solidification is offset to an appreciable degree by gas formation. Accordingly, this type of steel includes the entire range intermediate between rimmed and fully killed steel. The resultant ingot structures range from those of steels that have been capped to suppress a weak rimming action to those steels that have been killed in the furnace or ladle to the extent that no mold deoxidizer is required. A survey reported to the 1946 -AIME Open Hearth Conference' reviewed the practices being used at 28 major plants for the deoxidation of semikilled steel. It was found that most plants divide the deoxidizing additions between the ladle and the mold—many of the plants adding only minor amounts of deoxidizer to the bath or none at all. Silicon, aluminum and titanium were the only elements used for ladle and mold deoxidation. Mold deoxidizers were added as capping additions or as uniformly fed additions. Several practices were reported in which the steel was deoxidized in the ladle to the extent that little or no mold deoxidation was needed. No reference was made to grades capped by using special mold designs or special closures over the top of molds. .Accordingly, specific examples of this type of practice will not be considered in this paper. It appeared from this survey of deoxidation practice that semikilled steel can be divided into three types, namely, capped semikilled, in which aluminum is added near the end of pour or after shut-off, intermediate semikilled steels, in which aluminum is fed uniformly throughout the pour, and semikilled steels requiring no mold deoxidation. In an attempt to cover the ingot structures obtained by the range of practices reported in the preceding survey, three series of experimental heats were made using increasing amounts of aluminum, silicon and titanium for ladle deoxidizers. The ladle deoxidizers were added as stick aluminum, 50 pct ferrosilicon and 20 pct ferrotitanium (4 pct carbon), respectively. Two methods of studying ingot structures were used. Ingots were removed from production, burned longitudinally and machined to allow observation of the central pipe and coarse blowholes. During the machining operation much of the finely porous subsurface structure was obliterated. Accordingly, observations were also made

Jan 1, 1949

By Michael Tenenbaum

The importance of semikilled steel as a high tonnage grade has long been recognized. The increasing severity of the applications for which semikilled steel is used makes it desirable to obtain further information regarding the features of open hearth practice and ingot structure that can affect steel performance in subsequent rolling and fabricating operations. Accordingly, an investigation is being carried out studying the structure of various types of semikilled steel ingots. This paper reviews some of the observations made and information gathered in this investigation. By definition, semikilled steel may be considered to include all nonrimming steels in which the natural shrinkage occurring during ingot solidification is offset to an appreciable degree by gas formation. Accordingly, this type of steel includes the entire range intermediate between rimmed and fully killed steel. The resultant ingot structures range from those of steels that have been capped to suppress a weak rimming action to those steels that have been killed in the furnace or ladle to the extent that no mold deoxidizer is required. A survey reported to the 1946 -AIME Open Hearth Conference' reviewed the practices being used at 28 major plants for the deoxidation of semikilled steel. It was found that most plants divide the deoxidizing additions between the ladle and the mold—many of the plants adding only minor amounts of deoxidizer to the bath or none at all. Silicon, aluminum and titanium were the only elements used for ladle and mold deoxidation. Mold deoxidizers were added as capping additions or as uniformly fed additions. Several practices were reported in which the steel was deoxidized in the ladle to the extent that little or no mold deoxidation was needed. No reference was made to grades capped by using special mold designs or special closures over the top of molds. .Accordingly, specific examples of this type of practice will not be considered in this paper. It appeared from this survey of deoxidation practice that semikilled steel can be divided into three types, namely, capped semikilled, in which aluminum is added near the end of pour or after shut-off, intermediate semikilled steels, in which aluminum is fed uniformly throughout the pour, and semikilled steels requiring no mold deoxidation. In an attempt to cover the ingot structures obtained by the range of practices reported in the preceding survey, three series of experimental heats were made using increasing amounts of aluminum, silicon and titanium for ladle deoxidizers. The ladle deoxidizers were added as stick aluminum, 50 pct ferrosilicon and 20 pct ferrotitanium (4 pct carbon), respectively. Two methods of studying ingot structures were used. Ingots were removed from production, burned longitudinally and machined to allow observation of the central pipe and coarse blowholes. During the machining operation much of the finely porous subsurface structure was obliterated. Accordingly, observations were also made

Jan 1, 1949

By A. P. Miller, T. S. Washburn

Improved procedure in the manufacture of rail steel has come as the rail user demanded better wearing qualities combined with greater unit weight. With each weight increase per lineal yard has come greater difficulty in making a product that would successfully withstand all tests that modern rails must meet. With these facts in mind, and with a sincere desire to produce a rail whose service in track would be satisfactory in all respects, the steelmaker was quick to realize that all of the factors entering into his process would have to be more closely controlled. Control of rail-steel slags was recognized as one of the most important of many interdepending factors. The object of slag control is to hold the slag compositions within a range that gives the best results with respect to economy of production, uniformity of analysis, and quality of the finished rails. The most important component of the slag from the standpoint of these production and quality factors is the ferrous oxide content. This component is a good indicator of the basicity and oxidizing power of the slag, and these largely govern the effect of the slag on the steel. Consequently, the

Jan 1, 1935

By A. P. Miller, T. S. Washburn

Improved procedure in the manufacture of rail steel has come as the rail user demanded better wearing qualities combined with greater unit weight. With each weight increase per lineal yard has come greater difficulty in making a product that would successfully withstand all tests that modern rails must meet. With these facts in mind, and with a sincere desire to produce a rail whose service in track would be satisfactory in all respects, the steelmaker was quick to realize that all of the factors entering into his process would have to be more closely controlled. Control of rail-steel slags was recognized as one of the most important of many interdepending factors. The object of slag control is to hold the slag compositions within a range that gives the best results with respect to economy of production, uniformity of analysis, and quality of the finished rails. The most important component of the slag from the standpoint of these production and quality factors is the ferrous oxide content. This component is a good indicator of the basicity and oxidizing power of the slag, and these largely govern the effect of the slag on the steel. Consequently, the

Jan 1, 1935

Organization Place Date 1917 American Electrochemical Society Pittsburgh, Pa. Oct. 3-6 American Institute of Mining Engineers St. Louis, MO. Oct. 8-13 American Gas Institute : Washington, D. C. Oct. 16-19 American Institute of Architects Philadelphia, Pa. _ Dec.. 26-29 American Society of Mechanical Engineers New York City. Dec. 26-29 American Mining. Congress State Chapter Phoenix, Ariz. Dec. 26-29

Jan 10, 1917

By NORMAN EBBLEY

NUMEROUS references have been made recently to "Alaska's oil reserves," and in view of the wartime petroleum situation sober thinking demands a dispassionate and scientific study and investigation of these reserves or supposed reserves. The question naturally arises, "Is there actually oil in Alaska, or are the reserves there a supposition?" True, in 1923 President Harding established Naval Petroleum Reserve No. 4 in Alaska, certainly implying that oil was there. This reserve, embracing about 35,000 sq. mi., was set aside on the advice of the Bureau of Engineering of the Navy Department and was based upon the existence of known petroleum seepages at Cape Simpson on the Arctic coast. The Cape Simpson seepages have been known for more than fifty years, but in spite of persistent rumors of other seepages in northern Alaska no definite evidence of their existence has been available.

Jan 1, 1944

By J. Hoover Mackin

The iron ore bodies of the Iron Springs district are replacement deposits of magnetite and hematite in Jurassic limestone around the borders of three intrusions of quartz-monzonite porphyry. Production in the period 1923-1965 was about 72,000,000 tons, nearly all of which was direct-shipping ore from open pits. The intrusions are laccolithic in form; all three were emplaced at the same stratigraphic horizon, which had been a zone of decollement gliding during the Laramide orogeny. The intrusions and associated volcanic rocks are post-orogenic. There was no change in the thickness of the limestone during the metallization. Comparison of the composition of the limestone and stratigraphically equivalent replacement ore indicates that, with every million tons of iron, there were additions of 40,000 tons of silicon, 20,000 tons of magnesium, and 10,000 tons of aluminum. The ore-forming fluid was derived from the exposed porphyry. The iron was first incorporated in hydroxyl-bearing mafics, which crystallized in depth and were carried upward in the magma that formed the hypabyssal intrusions. The mafic phenocrysts decayed deuterically in the new environment, releasing iron into the interstitial fluid of a consolidating crystal mush in the interior of the intrusions. Primary tension joints, which opened in areas of late intrusive distention, served as roots through which the ore-forming fluid was drawn from the crystal mush.

Jan 1, 1968

By AIME AIME

PETROLEUM technology was the sole subject of discussion at the meeting of the Petroleum Division at the Baker Hotel, Dallas, Texas, Oct. 6-7, except for the brief talks by President Becket and Secretary Parsons at the dinner on Friday evening. Even on this occasion, following the scheduled official features, it was in order to talk "shop." W. E. Wrather and E. A. Stephenson, respectively Chairman and Secretary of the Division, had planned for a meeting of this nature and by preference, apparently, the 122 who registered fell in with the scheme wholeheartedly. Not because the competent local committee had not provided for it, but by choice, the members just did not sign up for entertainment or field trips, but did attend largely the three technical sessions and engage in earnest discussion of the approximately dozen excellent papers. In this connection, and without question, the high lights of the meeting were the papers by Morris Muskat and R. D. Wyckoff, and Prof. W. K. Lewis. The former, entitled, "A Theoretical Analysis of Waterflooding Networks," had been entirely demathematized by the authors for presentation at this and the Los Angeles meetings; the author of the latter, which was on the "Physical-chemical Relationships of Hydrocarbon Gas-liquid Mixtures at High Pres¬sures," had airplaned to Dallas in the company of Dr. H. D. Wilde from Chicago in order to present his paper at the final session on Saturday morning.

Jan 1, 1933

By FOSTER HEWElT

THE scope of this paper is the description of two districts in Peru in which deposits of vanadium have been found, and the consideration of much laboratory-work that I and others have done to determine the nature of these deposits. It is with regret that I present some of the data in a state of evident incompletion, particularly the analyses of a few of the minerals, which leaves some doubt as to whether the true nature of the minerals is understood. I make no apology, however, since in this case, as in many others referring to ore-deposits, conclusive opinions cannot be stated until a great amount of work has been done, and the deposit has been thoroughly exploited. I believe that the data and the tentative conclusions here presented indicate a unique and interesting condition which may assist others in work along similar lines; and further, what is of more practical importance, stimulate a search for a metal which, though long considered rare, is probably so merely because proper care has not been taken to recognize it. An excellent bibliography on the occurrence of vanadium in nature is given by F. W. Clarke in his paper, Data of Geo-chemistry;1 and in the preparation of this paper I have consulted many of the references contained in the Bibliography of the Chemistry of Vanadium, by M. Moissan.2 A brief review of the subject having special reference to the metallurgy of vanadium is contained in the small book by P.. Nicolardot.3 One of these vanadium-deposits has already been briefly

Mar 1, 1909

By C. Kremer Bain

DURING the past several years of diamond drilling in Washington County, Mo., the St. Joseph Lead Co. has discovered a concentration of commercial lead-zinc ore at four different points within an area of 36 square miles. The largest and to date the most promising group of these orebodies is located in the Indian Creek area. It was considered to be of sufficient value to warrant development.

Jan 9, 1953

By Herty, C. H.

Present-day interest in the question of "dirty steel" has arisen primarily from the increasingly rigid specifications on various grades of steel and from the growing conviction that non-metallic inclusions are the source of many of the difficulties in meeting these specifications. The importance of inclusions has unquestionably been over-emphasized in many cases, but on the other hand many unpublished instances could be recorded where all evidence pointed to inclusions as the primary cause for the failure of steel in rolling or in service. The solution of the problem of dirty steel is not a matter of a few years. There are almost numberless types of inclusions. They segregate in steel ingots in an entirely different manner from other impurities, and, at best, only a start has been made in developing correct analytical methods for their determination. Most of the writers in the field have expressed opinions rather than given facts, and so many variables enter into the manufacture of steel that a study of plant conditions is difficult unless definite facts on certain phases of the inclusion problem are available. This statement is not intended to convey the idea that little work has been done on this problem. On the other hand, the number of investigations has been large, but in most cases too many variables have been present to allow definite conclusions to be drawn. In the body of the text, reference to previous investigations is made at suitable points. Rather than burden the reader with a lengthy review of the literature on the general subject of inclusions, reference to the particular works pertinent to the subject matter of the bulletin has been discussed. Three excellent bibliographies b on the subject have been lately published: one by the Committee on

Jan 1, 1957

By Robert H. Merrill, David W. Wisecarver, Raymond M. Stateham

The US. Bureau of Mines, in cooperation with US. Borax and Chemical Corp. and Kennecott Copper Corp., has investigated the use of the microseismic method to evaluate the stability of large, open-pit slope walls. The method is based on the phenomenon that stressed rock normally emits subaudible rock noises, and the number of rock noises per unit time (noise rate) and the magnitude of the rock noises (amplitude) increase as the stresses in the rock approach the failure stress of the rock. Therefore, the detection and recording of those rock noises serve as a semiquantitative method of predicting the incipient failure of rock. This report briefly describes the three different types of micro-seismic apparatus, the procedures, and the results of microseismic investigations in the slope walls of the Boron mine near Boron, CaL, and the Kimbley, Liberty, and Tripp-Veteran open-pit mines near Ely, Nev. Microseismic monitoring within a frequency band of SO to 5000 Hz indicates noise rates in stable, inactive mining areas are between 0 and 10 noises per hour; the rates in stable, active mining areas are between 10 and 50 noises per hour; and the rate in unstable areas is as high as 2500 noises per hour. High microseismic noise rates in the Liberty pit correlate with the time of nearby earthquakes, indicating that the earthquakes affected the slope wall. The results provide evidence that the microseismic technique is applicable to large pit walls, and that the wide-band, wide-range microseismic equipment appears to be suitable for open-pit investigations. The microseismic method is based on the phenomenon that stressed rock normally emits subaudible rock noises, and the number of rock noises per unit time (noise rate) and the magnitude of the rock noises (amplitude) increase as the stresses in the rock approach the failure stress of the rock. Therefore, the detection and recording of those rock noises serve as a semiquantitative method of predicting the incipient failure of rock. The method has been used for many years to detect incipient failure in roofs or pillars in underground mines. In 1963 the U.S. Bureau of Mines (USBM) started an investigation of the microseismic method in large, open-pit slope walls. The purpose of this investigation was to evaluate the method in open-pit slopes where the rock may be fractured and broken and where the size of the rock mass under investigation is much larger than normally encountered underground. In addition, both the stresses in the rock and the strength of rock near pits are lower than usually found underground. Consequently, there was some doubt concerning the feasibility of the method for open pits, and the economics of such an investigation may have been prohibitive especially if large walls had to be monitored with closely spaced geophones. The successful application of the microseismic method to underground operations has improved safety at little, or no sacrifice, to production or extraction ratios. The anticipated reward in open-pit mining would be the improvement of safety with a minimum sacrifice to mining operations. There is also a possibility that the method could be used to optimize the unloading (stripping) of potential failure areas by the removal of intact rock from the slope wall rather than the cleanup of a slide from the bottom of the pit. This report contains a brief description of three types of microseismic apparatus used in four different pit walls, each of which is different in height, slope, rock types, or has different planes of weaknesses, such as faults, fractures, or joints. Because the geologic features of the pit walls are varied and complex, for brevity, this report dwells mostly on the microseismic apparatus, techniques, the rock noise rates, and the slope movements measured at the various sites. PROGRESS AND DEVELOPMENT The microseismic method was developed over 20 years ago; and the method and examples of investigations in underground mines are summarized by Obert and Duvall. 1 In more recent years, the method has been applied in several underground mines, and an in-situ test under controlled stress conditions is described by Morgan and Merrill. 2 Experience has shown that, on occasions, the microseismic noise rate and amplitude reach a peak value and then start to decrease before a failure occurs in an underground mine; on other occasions, the noise rate steadily increases to a maximum at failure. The method has been applied to slopes by Goodman and Blake,3 and by Paulsen. 4 Goodman and Blake found that the noises corresponded with failures in the slope

Jan 1, 1970

By William P. Blake

(Canal Zone Meeting, November, 1910.) A DEPOSIT of manganese-ore near Tucson, Ariz., merits notice by reason of the peculiar form in which it occurs, and as a striking. example of ore-deposition by vadose upward capillary flow of metal-bearing solutions with concentration at the surface of the country-rock. This deposit occurs at the northern end of the Coyote mountains, about 40 miles west of Tucson, upon the outcropping beds of porphyritic rock, which appear to be partly-metamorphosed strata of volcanic tufa, probably of late Secondary or of Tertiary age. The strata dip northward at a low angle, and present a series of basset-edges in parallel lines of outcrop, east and west, facing the south and extending over many acres. Successive groups of these outcrops, from 5 to 20 ft. in breadth, are coated with oxides of manganese in lustrous black films and crusts, shining in the sunlight like polished ebony, and covering the whole surface of the rock above the soil. Seen at a little distance, these croppings look like solid ledges of massive and pure ore; but closer inspection and a few blows of the hammer reveal their true nature as a superficial coating allied in origin to the blackened shining surface of rocks exposed in desert-regions, familiarly known as " desert paint" or "desert varnish,"' similar to the phenomena described by me in a former paper, but much thicker and heavier. * By reason of the death of the distinguished author, this communication, probably his last communication to technical literature, is published without revision of the proofs by him. A term first given y G. K. Gilbert. See Rocks, Rock-Weathering, and Soil; by George P. Merrill, p. 256 (New York, 1897). Superficial Blackening and Discoloration of Rocks, Especially in Desert Regions, Trans., xxxv., 371 (1905).

Sep 1, 1910

By R. V. Norris

The anthracite coal trade, with a shipment averaging about 70,000,000 tons per year, differs essentially from other coal business, iii the fact that the larger sizes, comprising about 65 per cent. of the total, are used almost exclusively for domestic purposes, principally during the winter months; and that for proper combustion close-sizing is imperative, so that eight sizes are made; broken, egg, stove, and nut, known as prepared sizes, and pea, buckwheat, rice, and barley, known as steam sizes. These sizes are made in the regular course of preparation, and but little variation in the natural percentage of each is practicable. Thus it is necessary either to work the collieries intermittently, or to dispose of all the varying sizes in their fixed proportions. Unfortunately, the market does not at all times absorb the coal in proper proportions, and rather than interfere with the regular operation of the mines it has been found economical to provide storage for the excess. While the cellars of' the consumers are the great storage-plants of the country, this capacity is not under the control of the trade, except so far as reduced prices during the spring and summer months may tempt the use of this reserve. The same remark applies but with less force to the retail yards, which, though usually small, store in the aggregate a large amount of anthracite. While every effort is made to utilize to the utmost the individual storage-capacity of the country, there still remains the necessity for taking care of the irregularities of the market by the construction of storage-plants under the direct control of the producers. Such plants are usually the property of the railroads, and are situated at points most convenient from a traffic stand-point.

Jan 1, 1912