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By Ralph C. Flow

In Cleveland County, North Carolina, 1 ½ miles south of Kings Mountain, Foote Mineral Co. operates an open pit for the production of spodumene, feldspar, mica and commercial stone. Spodumene concentrate is sent to Foote Mineral's Sunbright, Va., plant and to other customers. Exton, Pa. and New Johnsonville, Tenn., plants produce lithium com- pounds sold to the oil industry for multipurpose lithium-base greases, to the metal industry as welding flux, to the air conditioning market and to the glass industry. Ceramic-grade spodumene, feldspar, and mica concentrates go to other processing companies from the Kings Mountain plant. Waste amphibolite is delivered to a neighboring quarry operation. Geology and exploration of the deposit have been described by T. L. Kesler, Chief Geologist of Foote Mineral Co., in the September 1961 MINING ENGINEERING. Measured ore reserves as published at that time were 20.7 million tons. The ore deposit consists of a series of lithium-bearing pegmatites enclosed in amphibolite and mica schist wall rocks. The general strike of the pegmatites is northerly, and in the southern part of the pit, they dip slightly towards the west. The largest body being mined has a fairly uniform thickness of about 200 ft. Other pegmatites in the pit area range from 20 to 100 ft in thickness. Minerals in the pegmatites are 20% spodumene, 32% quartz, 6% muscovite, 41 % feldspar and 1 % trace minerals.

Jan 10, 1962

By David Cole

AT the time flotation appeared upon the metallurgical horizon in Arizona, the writer, under the direction of Dr. Ricketts, was engaged in remodeling and enlarging the No. 6 Concentration Plant of the Arizona Copper Co. at Morenci, and the work had been in progress nearly a year before the Inspiration experiments with flotation had disclosed the revolution in concentration that was at that timè impending. The simplified flowsheet worked out for the remodeling of the Morenci plant had been based upon the removal of the freed metal in a minimum number of stages by treatment upon tables equipped with Butchart riffles, the latter being adapted to accomplish both classification of feed and removal of the metal at one operation, substantially as described in my previous paper.1 The scheme of treatment for the slime was based upon the well-known fact that after copper sulphides, such as chalcocite and chalcopyrite, etc., are reduced to a certain extremely fine state of comminution they are definitely beyond the reach of separation upon any of the concentrating devices then known. By using drag-belt classifiers (which served as conveyors as well as separators), the overflow would be of the usual "slimes" class. Experiment had shown that when these drag-belt overflows were, properly diluted (that is, to about 5 to 7 per cent. solids in the feed under treatment) . the very fine sand, and especially the very fine but still granular sulphide particle's, would, if given a short distance to fall, quickly settle out in prime condition to yield an excellent recovery on vanners; a further valuable feature would be that the very fine non-separable final overflow tonnage might be discharged direct to tailing, thus conserving space requirements so as to permit within the old building, without embarrass-ment, the increase of capacity required.

Jan 9, 1916

By Grimes, J. A.

EXTENSIVE discovery 'and rapid exploitation of orebodies within the past half century have attracted many able geologists to the mining industry and furnished them a wealth of data from which to develop theories concerning ore genesis. By tosting and elimillating theories which are not sufficiently sup- ported by fact, or which are based on inaccurate observation of field data, the trend of geological opinion has . moved strongly in certain directions until, at the present time, large numbers of geologists subscribe to a broad concept of .ore genesis that I would summarize as below:

Jan 1, 1928

The classification here used is one of convenience only; it is not intended to include all known types of ore deposits. The characteristic features of the several well-marked types of primary mineralizations are described without reference to the ultimate source of their metals. The minerals of many deposits of obscure origin were probably introduced through fissures that are now healed, or are due to the migration of metals from such deposits. [ ] It is not within the scope of this book to enter into a general discussion of the genesis of ore deposits but, in view of the progress being made in our comprehension of the conditions under which ore deposits were formed, mention should be made of recent work. J. E. Spurr's two volumes, "The Ore Magmas," are recommended as crystallizing the views of those who are inclined to ascribe the origin of most ore deposits to a differential precipitation from magmatic rock masses and to the migration and precipitation of the viscous, liquid or gaseous exhalations from those masses. He has especially emphasized the role

Jan 1, 1932

OFFICERS AND COMMITTEES OF LOCAL SECTIONS AIME Committee on Local Section Affairs Roger Pierce, Chairman Carleton C Long Thomas C Frick AIME Committee on Student Chapter Affairs John P Nielson, Chairman John C Calhoun, Jr J R Van Pelt, Jr Council of Section Delegates A A Burr, Chairman (Hudson-Mohawk) Ralph A Watson, Vice-Chairman (North Pacific) L G Neely, Secretary (West Central Texas) INTERIM COMMITTEE M O Langham (East Texas), Fulton J Olivier (Delta), L W Smith (Niagara Frontier), G R Spindler (Central Appalachian) LOCAL SECTIONS (There are 78 Local Sections in the United States, 9 Foreign) ADIRONDACK Established June 18, 1952 Official year begins in April Meets fourth Saturday monthly, April through October Seven meetings annually Local Section Dues AIME Members $2, Nonmembers $3 Charles F Dievendorf, Chairman Severn P Brown, Vice-Chairman George E Erdman, Secretary-Treasurer Gouverneur Talc Co , Inc Gouverneur, N Y Malcolm V Lowry, '60, Section Delegate Committees Membership David J Crawford, Chairman Program Brower Dellinger, Chairman Student Affairs Eugene A Eastman, Chairman

Jan 1, 1959

By Albert Sauveur

THE following experiments were conducted in order to study the influence of the rate of cooling through and below solidification on the dendritic structure (macrostructure) and microstructure of some hypoeutectoid steel. The steel selected was of commercial grade and had the following composition: C, 0.40 per cent.; Mn, 0.85; Si, 0.70; P, 0.099; S, 0.043. After melting in vacuum in an Arsem furnace, the various samples were allowed to solidify and to cool to room temperature as indicated in Fig. 1. Samples were thus obtained representing all possible combinations of slow and fast cooling through the various ranges of temperatures indicated, namely: (1), zone of solidification or primary crystallization, (2) zone of granulation, and (3) zone of secondary crystallization. The location of the different temperature zones in the iron-carbon equilibrium diagram is shown in Fig. 2. The authors adopted. Belaiew's notations. The designations of the various samples readily indicate their treatment, as will be apparent from Table 1.

Jan 1, 1930

By ALFRED T. BARR

In certain areas of the New Cornelia pit, considerable secondary blasting is necessary to reduce oversized boulders, formed from primary blasting, to pieces which will pass the 41/2-cu yd dippers on the shovels. Some of the boulders are 'dobied, but when time permits they are blockholed and blasted. In most instances one hole drilled to a depth of 2 to 3 ft and blasted with 1/3 to 1/2 of a stick of powder will break a boulder satisfactorily. Blockholing is normally done by using a jackhammer of the 55-lb class, 1-in. round drill steel, and detachable steel bits, 2-in. gauge when new. A bit change is usually made after the completion of each hole. The use of light drilling equipment in blockholing is desirable, both from the standpoint of safety and ease of doing the work, and when it was seen there was a possibility of using a lighter jackhammer through the use of tungsten-carbide bits and at the same time get at least the same drilling efficiency as with the standard equipment, it was decided to test tungsten-carbide bits. The claims for long life of the bits and footage drilled before resharpening gave hopes of eliminating much of the delay time in changing bits which is unavoidable with the use of steel bits. and thus gain in actual drilling time.

Jan 1, 1949

By C. E. Shoenfelt

Jan 1, 1942

By C. E. Shoenfelt

Jan 1, 1942

By Walter Rose, W. A. Bruce

Improved apparatus, methods, and experimental techniques for determining the capillary pressure-saturation relation are described in detail. In this connection a new multi-core procedure has been developed which simplifies the experimental work in the study of relatively homogeneous reservoirs. The basic theory concerning the Leverett capillary pressure function has been extended and has been given some practical application. Some discussion is presented to indicate the relationship of relative permeability to capillary pressure, and to provide a new description of capillary pressure phenomena by introducing the concept of the psi function. INTRODUCTION For the purposes of this paper the capillary character of a porous medium will be defined to express the basic properties of the system, which produce observed results of fluid behavior. These basic properties may be classified in the following manner, according to their relationship to: (a) The geometrical configuration of the interstitial spaces. This involves consideration of the packing of the particles, producing points of grain contact, and variations in pore size distribution. The packing itself is often modified by the secondary processes of mineralization which introduces factors of cementation, and of solution action which causes alteration of pore structure. (b) The physical and chemical nature of the interstitial surfaces. This involves consideration of the presence of interstitial clay coatings, the existence of non-uniform wetting surfaces; or, more generally, a consideration of the tendency towards variable interaction between the interstitial surfaces and the fluid phases saturating the interstitial spaces. (c) The physical and chemical properties of the fluid phases in contact with the interstitial surfaces. This involves consideration of the factors of surface, interfacial and adhesion tensions; contact angles; viscosity; density difference between immiscible fluid phases; and other fluid properties. Fine grained, granular, porous materials such as found in petroleum reser~oir rock possess characteristics which are expressible by (1) permeability, (2) porosity, and (3) the capillary pressure-saturation behavior of immiscible fluids in this medium. These three measurable macroscopic properties depend upon the microscopic properties enumerated above in a manner which defines the capillary character. Systems of capillary tubes or regularly packed spheres may be thought of as ideal and numerous references can be cited in which exact mathematical formulations are developed to show the relationships governing the static distribution and dynamic motion of fluids in their interstitial spaces. The capillary character of non-ideal porous systems such as reservoir rock also is basic in determining the behavior of fluids contained therein; although, in general, the connection is not mathematically derivable but must be approached through indirect experimental measurement. This paper gives consideration to the evaluation of petroleum reservoir rock capillary character. The methods employed may be applied to the solution of problems in other fields, and the conclusions reached should contribute to the basic capillary theory of any porous system containing fluid phases. In this paper, a modification of the core analysis method of capillary pressure is employed and it is intended to show that the capillary character of reservoir rock can be expressed in terms of experimental quantities. A very general method of interpretation correlating the capillary pressure tests with fundamental characteristics such as rock texture, surface areas, permeability, occasionally clay content and cementation is introduced. Eventually an attempt is made for establishing a method of deriving relative permeability to the wetting phase from capillary pressure data. The experimental evaluation of capillary character must be approached in a statistical manner if reservoir properties are to be inferred from data on small cores. This is implied by the heterogeneous character of most petroleum reservoirs, and suggests that considerable intelligence should be applied in core sampling. Finally, this paper supports the view that once the capillary character of a given type of reservoir rock has been established by core analysis, fluid behavior can then be inferred in other similar rock. Although no great progress has been made in establishing what variation can be tolerated without altering the basic fluid behavior properties, evidence will be presented to indicate that certain reservoir formations are sufficiently homogenous with respect to capillary character that the data obtained on one core will be useful in predicting the properties of other cores of similar origin. Tests have shown that cores under consideration can vary widely with respect to porosity and permeability and still be considered similar in capillary character. EXPERIMENTAL METHODS AND TECHNIQUES Various types of displacement cell apparatus for capillary pressure experiments have been described in the literature. Bruce and Welge; Thornton and Marshall; McCullough, Albaugh and Jones3; Hassler and Brunner; Lever-

Jan 1, 1949

By Walter Rose, W. A. Bruce

Improved apparatus, methods, and experimental techniques for determining the capillary pressure-saturation relation are described in detail. In this connection a new multi-core procedure has been developed which simplifies the experimental work in the study of relatively homogeneous reservoirs. The basic theory concerning the Leverett capillary pressure function has been extended and has been given some practical application. Some discussion is presented to indicate the relationship of relative permeability to capillary pressure, and to provide a new description of capillary pressure phenomena by introducing the concept of the psi function. INTRODUCTION For the purposes of this paper the capillary character of a porous medium will be defined to express the basic properties of the system, which produce observed results of fluid behavior. These basic properties may be classified in the following manner, according to their relationship to: (a) The geometrical configuration of the interstitial spaces. This involves consideration of the packing of the particles, producing points of grain contact, and variations in pore size distribution. The packing itself is often modified by the secondary processes of mineralization which introduces factors of cementation, and of solution action which causes alteration of pore structure. (b) The physical and chemical nature of the interstitial surfaces. This involves consideration of the presence of interstitial clay coatings, the existence of non-uniform wetting surfaces; or, more generally, a consideration of the tendency towards variable interaction between the interstitial surfaces and the fluid phases saturating the interstitial spaces. (c) The physical and chemical properties of the fluid phases in contact with the interstitial surfaces. This involves consideration of the factors of surface, interfacial and adhesion tensions; contact angles; viscosity; density difference between immiscible fluid phases; and other fluid properties. Fine grained, granular, porous materials such as found in petroleum reser~oir rock possess characteristics which are expressible by (1) permeability, (2) porosity, and (3) the capillary pressure-saturation behavior of immiscible fluids in this medium. These three measurable macroscopic properties depend upon the microscopic properties enumerated above in a manner which defines the capillary character. Systems of capillary tubes or regularly packed spheres may be thought of as ideal and numerous references can be cited in which exact mathematical formulations are developed to show the relationships governing the static distribution and dynamic motion of fluids in their interstitial spaces. The capillary character of non-ideal porous systems such as reservoir rock also is basic in determining the behavior of fluids contained therein; although, in general, the connection is not mathematically derivable but must be approached through indirect experimental measurement. This paper gives consideration to the evaluation of petroleum reservoir rock capillary character. The methods employed may be applied to the solution of problems in other fields, and the conclusions reached should contribute to the basic capillary theory of any porous system containing fluid phases. In this paper, a modification of the core analysis method of capillary pressure is employed and it is intended to show that the capillary character of reservoir rock can be expressed in terms of experimental quantities. A very general method of interpretation correlating the capillary pressure tests with fundamental characteristics such as rock texture, surface areas, permeability, occasionally clay content and cementation is introduced. Eventually an attempt is made for establishing a method of deriving relative permeability to the wetting phase from capillary pressure data. The experimental evaluation of capillary character must be approached in a statistical manner if reservoir properties are to be inferred from data on small cores. This is implied by the heterogeneous character of most petroleum reservoirs, and suggests that considerable intelligence should be applied in core sampling. Finally, this paper supports the view that once the capillary character of a given type of reservoir rock has been established by core analysis, fluid behavior can then be inferred in other similar rock. Although no great progress has been made in establishing what variation can be tolerated without altering the basic fluid behavior properties, evidence will be presented to indicate that certain reservoir formations are sufficiently homogenous with respect to capillary character that the data obtained on one core will be useful in predicting the properties of other cores of similar origin. Tests have shown that cores under consideration can vary widely with respect to porosity and permeability and still be considered similar in capillary character. EXPERIMENTAL METHODS AND TECHNIQUES Various types of displacement cell apparatus for capillary pressure experiments have been described in the literature. Bruce and Welge; Thornton and Marshall; McCullough, Albaugh and Jones3; Hassler and Brunner; Lever-

Jan 1, 1949

Jan 1, 1916

By C. WIFLARD HAYES

(New Haven Meeting, February, 1909.) I DESIRE to make it perfectly clear at the outset that I fully realize the hazardous nature of any attempt to estimate the quantity of iron-ore or any other mineral in the ground. I should not have had the temerity to venture upon an inventory of the iron-ore supplies of the United States except for the requirements of the Conservation Commission. During the preparation of this inventory I have been impressed by the wide diversity in estimates of those best qualified to. hold an opinion, and I am therefore prepared in advance for criticism of my figures. Inasmuch as this report was prepared in large part for unprofessional readers, I considered it necessary to classify and describe the commercial iron-ores in a somewhat elementary manner, in order to explain the reasons for the large element of uncertainty in the estimates. I have therefore given a chemical and a geological classification of iron-ores, which place the commercial deposits in six classes: (1) magmatic segregations in basic igneous rocks; (2) contact-deposits formed in connection with igneous intrusions; (3) concentration-deposits; (4) replacement-deposits; (5) bedded-deposits, and (6) gossan-deposits. The iron-ores are further distinguished under two classes available and not available. This classification is in large measure arbitrary, and it, is evident that it will vary front time to time. In the available class are placed those ores which can be worked at a profit under conditions essentially as they exist at present. Since it depends wholly on the question of costs, the various factors which affect cost will determine the classification of any particular deposit. Actual production, * Abstract of Report prepared for the Conservation Commission. t Chief Geologist, United States Geological Survey. .

Apr 1, 1909

By E. Z. Lajtai

The probability distribution of fracture data from a rock mechanics test contains information about the effectiveness of the testing procedure and/or about the nature of the operating failure mechanism. The tensile strength of Lac du Bonnet granite forms a bimodal probability distribution when determined through line loading as in the Brazilian test. The same data obtained from three point bends tests are unimodal. The bimodality can in part be removed by distributing the line load over a finite area. Moisture has the anticipated effect in lowering both the average compressive and the average tensile strength of Lac du Bonnet granite. The reduction in strength however is not uniform within the probability distribution; the change is the largest at low and the smallest at high strength. Conversely, long-term loading is more damaging to the high strength members of the distribution. The large scatter of failure times in static fatigue experiments can in part be removed or even utilized when the probability distribution of instantaneous strength is taken into account.

Jan 1, 1982

By Krahmann, Rudolf

THE following is an account of a survey undertaken to test the possibility of outlining a kimberlite pipe by magnetouietric methods. Kimberlite is a basic igneous rock closely related to melilite-basalt or alnoite, which occurs either in the form of volcanic plugs or as dikes intruded into rocks of various types and geological ages up to and includ¬ing the Lower Cretaceous. The famous diamond mines of South Africa are all in kimberlite pipes and these pipes are probably the original source as well of the vast alluvial deposits found in various parts of the country. The pipe chosen for this experiment is one that ' occurs on the farm Goedgevonden No. 20, about sixteen miles north of the village of Klerksdorp and ninety miles southwest of Johannesburg. Some prospecting has been done on this pipe and diamonds were produced from it but not in paying quantities. The magnetometric survey was made in June, 1932, by R. Krahmann and H. Wallisch and the results are shown on the accompanying plan. On the plan are shown also the boundaries of the pipe as exposed at the surface and details in regard to the surrounding foundations. These are taken from a geological survey made at a later date by W. Beetz, of Johannesburg.

Jan 1, 1935

By John M. Lovejoy

CURRENT production of petroleum on such a vast scale presents many interesting problems- the solutions of which are important not only to those directly interested in the business, but to the nation as a whole. The industry is relatively young. Until the discovers of the Lucas gusher at Spindletop in 1901 petroleum production had not exceeded 60,000,000 bbl. per year compared with 1,100,000,000 bbl. in 1936. In 36 years then, the modern oil business, production, transportation, refining, and marketing has developed. I will first present a brief history. of oil production as a background for consideration of the present situation.

Jan 1, 1937

By B. B. Gottsberger

HAVE given considerable thought during the past year to the subject of licensing of engineers and par-ticularly to the position which the mining engineer should take on this question. I have found, however, that it is not a subject which yields much result for the thought expended on it. So far as any published record will show, mining engineers have been either ignorant of the extent to which the movement for the licensing of engineers has progressed or else indifferent to it. It is true that the Mining and Metallurgical Society of America, by a questionnaire sent out to its member-ship, did a great deal in calling this matter to the atten-tion of the mining profession, and so far as I know, the report of its committee, which analyzed the replies received, is the only published statement of the feelings and opinions of our branch of the engineering profes-sion. It is to be hoped that the conclusions shown by that report, namely, that mining engineers are almost unanimously opposed to the principle of licensing and consequently any legislation dealing with it, has received serious thought and that we are ready for an even more thorough consideration of the subject.

Jan 3, 1922

By Edwin Hopkins

The year of 1924, in Venezuela, has been one of especial interest. The figures for production marketed are not so impressive, but to the well-informed followers of the development, the ease with which this production has been obtained and with which it apparently can be increased at will merits most careful consideration. For several years, the oil world, especially in the financial centers, has been closely following the slow unfolding. of the' Venezuelan developments, which has been, and still is, one of the great pioneering achievements in the history of oil exploitation. Venezuela, from the first days of its recognition by geologists and financiers as a great future source of oil, has been a field for the enterprising vision of the larger capital groups. The laws of the country have been drafted with almost an inspired foresightedness that has favored the exploitation of the resources along constructive lines, which' has eliminated the irrational promotion schemes that accompany many of the oil developments in the United States. Developments have been exclusively in the hands of strong financial groups, who have followed a conservative policy with respect to the dissemination of detailed information concerning the geological findings and detailed production data. Within the last year, however, the rapid expansion of the production phase of the developments has been on such an important scale and has involved such a large and rapidly increasing personnel, that further restraint with respect to information of a general informative' nature can serve no useful purpose. Certainly, from the volume of references to Venezuelan oil affairs, which are now of almost weekly occurrence in the oil trade journals, the public must appreciate the fact that in Venezuela, and in the Maracaibo district in particular, a new oil region of the first magnitude is about to emerge from comparative obscurity and occupy a commanding position on the stage of world oil affairs.

Jan 3, 1925

By E. DeGolyer

USE of geophysical methods as an aid to prospecting for new oil pools and in the exploration of already discovered pools continued to increase and reached a new high during 1934. As in previous years, the scene of greatest activity was the Gulf coastal plain of Texas and Louisiana. Seismic crews working by the reflection method increased from some thirty crews at the first of the year to forty crews at the end. An increased demand for torsion balance work at the beginning of the year occurred and practically all available instruments were put into service. Some thirty crews with approximately eighty balances continued throughout the year. Both the pendulum and gravimeter methods of gravity surveys registered their initial successes and equipment was increased from five to seven pendulums and from one to three gravimeters during the year. Approximately five magnetometer parties continued to work throughout the year. No surface surveys by the electrical method are known to have been made. Outside of coastal Texas and Louisiana the chief geophysical work

Jan 1, 1935

By F. L. Clerc

The lead and zinc region of SW. Missouri is interesting, not only by reason of the value of its output, which ranges in the neighborhood of ten million dollars a year, but even more because of the facilities which it offers for the study of certain forms of ore-deposits, of' which the loci and genesis are somewhat obscure. Although the mineral species found in the region are few and of common occurrence, crystallization has taken place on a generous scale, and unusual forms abound in many combinations, presenting examples of pseudomorphism, para-genesis, metasomatic replacement and the action of mineral-depositing and mineral-dissolving waters. For the mineralogist, lithologist, and specialist in certain lines of metamorphism, it has peculiar attractions, while the systematic geologist will perhaps find its chief claim to attention in the simplified problem it presents, in the study of ore-deposits. In addition to the phenomena above enumerated, it presents instances of well-developed comb-structure in the ores, fissures and faults, and slickensides—features usually associated with extensive movements in the earth's crust, and believed by some authorities to prove the deep-seated origin of the ores. In connection with these occurrences, the absence of all igneous rocks from this region is noteworthy and significant. For that reason, the simplified case presented by the Joplin region, from which these rocks have been eliminated as a factor, is specially valuable. Having had unusual opportunities to watch the development of this district, I have been deeply interested in the bearing of the revelations of the Joplin mines upon questions of universal importance to the science of ore-deposits; and it was to my great regret that the project of a meeting of the American Institute of Mining Engineers at Joplin, proposed in 1892, was

Jan 1, 1908