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By James C. Fisher

Traditional uranium exploration techniques were utilized and comparatively evaluated in the Front Range, Colorado uranium province. Intense surficial leaching and thick colluvial cover render traditional airborne and ground radioactivity reconnaissance prospecting useless. Radon gas emanometry and sulfur gas emanometry were slightly more effective but the long and short term variations In soil gas emanation rates make it extremely difficult to gain useful information from these systems. The technique judged most useful was Track Etch radon prospecting. The excellent definition of the technique, as well as its repeatability, indicate that it is an ideal prospecting tool for narrow vein-type deposits similar to those of the Front Range, Colorado.

Jan 1, 1976

By R. Haynes

ON the basis of compositional changes of a phase observed in a eutectoid Cu-Al alloy1 it has been suggested that mechanisms for the decomposition of the ß phase proposed by earlier workers2-5 were incorrect. These data are reinterpreted in conjunction with lattice parameter data obtained on an alloy containing 12.2 pet Al, whose isothermal transformations have been reported elsewhere.5 The a Lattice Parameters of a 12.2 Pet A1-Cu Alloy—~iffraction patterns of completely transformed specimens were obtained in a back reflection camera using copper Ka radiation. Lattice parameters of

Jan 1, 1959

By S. A. Braley

THE first commercial production of bituminous coal in the United States was in 1820, and formation of acid in the areas from which the coal was removed began at that time. Thus it is 130 years since the development of mine acid began. The coal operator has had to deal with the acid water produced in his mines, and his losses from corrosion of pumps and equipment have been tremendous. Other industries and the public have been forced to spend large amounts for their water requirements because of the acid discharge from the mines. There are many contradictions in the literature on this subject probably because of variations in the analytical procedures followed and differences in the methods of calculation and reporting. The opinions previously expressed may be summarized as follows:

Jan 8, 1951

By Antonio Marrano, Eda F. Quadros, Diogo Correa [Fo], Paulo T. Cruz

For many years the water pressure test has been used as a normal procedure to investigate the hydraulic characteristics of rock masses and discontinuities. Although the test has given evidence of problematic areas, the nature of flow and the so called equivalent permeability are seldom seriously affected by the testing tecnique. In order to improve the information on these points the Instituto de Pesquisas Tecnológicas de São Paulo - IPT, has developed an extensive program at laboratory and field research on the hydraulics at rock fractures. This paper summarizes the main items related to this research. Is shows that with only small improvements on field tests and some support of laboratory conductivity tests on natural rock joints it is possible to obtain a better understanding of the nature of flow in fractures, improve flow predictions and estimate the opening and hydraulic conductivity, as well as the transmissivity of natural joints or rock discontinuities.

Jan 1, 1982

I. MCLAUGHLIN, R. P.-Protecting California Oil Fields from Damage by Infiltrating Water. Discussed by M. E. Lombardi, A. F. L. Bell, A. C. McLaughlin, R. P. McLaughlin, William A. Williams, Mark L. Requa, C. D. Keen 2413 BEST, W. N.-Petroleum as Fuel Under Boilers and in Furnaces. Discussed by William A. Williams, Hennen Jennings, David T. Day, Mark L. Requa, A. F. L. Bell, W. N. Best 2420 JOHNSON, ROSWELL H.-Sliding Royalties for Oil and Gas Wells. Discussed by William A. Williams, A. C. McLaughlin, A. F. L. Bell, Roswell H. Johnson 2423 BELL, ARTHUR F. L.-Important Topping Plants of California. Discussed by William A. Williams, David T. Day, A. F. L. Bell 2426 LOMBARDI, M. E.-The Cost of Maintaining Production in California Oil Fields. Discussed by C. D. Keen, Mark L. Requa, H. M. Bacon, M. E. Lombardi 2427 HUNTLEY, L. G.-Oil, Gas, and Water Contents of Dakota Sand in Canada and United States, Discussed by E. W. Shaw 2428

Jan 12, 1915

By S. T. Yuster

An analysis has been made of the factors responsible for tilted fluid contacts in petroleum reservoirs. The factors are static and dynamic with the former being controlled by those variables responsible for the capillary rise of fluids, and the latter include rate of formation tilt and hydraulic circulation. The explanation that rate of formation tilt may be responsible for tilted contacts appears untenable. The role of some of these factors in the migration, fractionation. accumulation and possibly the prospecting for oil is indicated. INTRODUCTION While it is generally considered that the segregation of gas, oil, and water in a petroleum reservoir results in approximately horizontal planes separating these phases. there are factor; which modify this simplified picture to a very great extent. Some of these factors are static. and the departure of the fluid interfaces from horizontal may represent a static equlibriun. Some of these factors may be dynamic and the interface positions may be non-equilibrium and represent a steady .state condition. Of course combinations of these two situations may also exist. The reasons most commonly given for this behavior are hydraulic circulation of fluids, change in character of the formation, and a rate of tilt of the formations more rapid than the rate at which the fluids may re-establish an equilibrium. Russell's Principles of Petroleum Geology' contains an extensive discussion of tilted fluid interfaces and their importance in the migration and accumulation of petroleum. Russell cites examples of tilted water tables at Lance Creek, Wyo.; Rock River, Wyo.: Cut Bank. Mont.; Cushing, Okla.: and Graham; Okla. Also given was the Wasson Field of West Texas which has saucer shaped oil-water and gas-oil interfaces with the saucer being deeper in the case of the oil-water contact. The Bradford Field in Pennsylvania has a tilted water table. San Ardo. Coalinga None and some other California field.; have tilled contacts. A recent paper by King Hubbert discuses the effect of hydraulic circulation of the water underlying the oil in a given stratun and it- implications in the accumulation of and drilling for the oil. The foregoing would indicate that tilted fluid interfaces are not uncommon and that it would be of importance to underbtand the forces which are responsible. Further. it would be of interest to examine certain idealized models of situations which may cause tilting with the thought in mind of deriving relatinnships between the important variables. These relationships may only hold exactly for the model* assumed but the results may apply semi-quantitatively to actual formations and at least indicate trends. The discussion will be divided into the effect of static factors and the effect of dynamic factors. STATIC FACTORS It has already been mentioned that one reason given for tilted contacts is a variation in formation properties. Specifically this is a change in the pore size of the formation capilaries. If the internal surface of the reservoir is preferetially wet by water, capillarity will cause the water 10 rise to a greater extent above the free water table in a small capillary than in a large one. Consequently the water-oil contact will be higher in the lower permeability sands than in the higher permeability sand.;. The free water table may be defined as the position the oil-water interface would take if capillarity were absent. Since the phenomenon is the capillary rise of water in an oil environment, a derivation of this shold give a relationship between the variables. Fig. 1 is an idealized model of the situation with a uniform bore circular capillary ubstitttting for the tortuous non.circular formation pore. The upward force.; on the column of water will be equated to the forces downward to give the equilibrium situation. forces upward = force downward where r is the radius of the capillary in ceritimetera. a is the interfacial ten4on oil-water in dynes per centimeter, 0 is the

Jan 1, 1953

By T. Nakao

Fujiwara quarry had been operated by the glory-hole benchcut mining system, but as it became difficult to meet expanding demand with this system, a central-shaft mobile crushing plant (MCP) system was introduced in 1979. This MCP is equipped with a hydraulic walking system manufactured for the first time in Japan. Central-shaft mining is now the common mining method of Japanese limestone quarries. With this method, crushing facilities are usually installed at the bottom of the shaft. But at the Fujiwara quarry, MCP was adopted and installed on the quarry surface. Many MCPs are operated in foreign countries, but few examples exist in Japan. Normally, Japanese limestone deposits lie in high mountain, obviously making it inconvenient for MCPs to walk in and around the quarry. This difficulty, however, was overcome, and the MCP has operated satisfactorily and efficiently for two years since its installation. To overcome difficulties in the central-shaft MCP mining system, two mining methods are employed: the slice-down method and the block-cut method.

Jan 1, 1985

For the convenience of members who may be traveling from place to place, the Secretary has compiled a list of libraries or other places in the United States and foreign countries where MINING AND METALLURGY or the Transactions may be consulted. This list will be sent to members if they so request. LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION TO MARCH, 1920 [ ]

Jan 1, 1925

By Calvin Bjorne, John Keeley

In the face of a highly competitive iron ore market, the Cleveland-Cliffs Iron Co. developed a process now being practiced at the company's Republic mine in Michigan's Upper Peninsula. By this process, a specular hematite crude ore is being beneficiated to produce a high iron-low silica concentrate with a suitable size structure for the production of a high quality pellet. This process involves crushing, primary grinding and primary flotation, followed by regrinding, heating and refloating the primary flotation concentrate. The ores consist predominantly of specular hematite with relatively minor amounts of magnetite and martite in a recrystallized chert gangue. A wide variety of silicates have been identified, particularly in association with intrusives of various description. The more abundant of these are sericite, talc, grunerite and chlorite with some carbonates, primarily calcite.

Jan 6, 1964

By Luke L. Y. Chang, Bert Phillips

A number of molybdenum oxides have been synthesized and their crystal structures have been described.' No data have been published on the stabilities of these oxides nor on the phase relations in the system Mo-0. It is probable that the tendency toward oxidation of both the metal and the oxides with low oxygen content in addition to the high volatilization rate of the oxides with high oxygen content have precluded accumulation of reliable data for establishing phase relations. These problems make experimentation difficult, but a modifi-

Jan 1, 1965

By O. Vartiainen, R. T. Hukki

A preliminary investigation of the collecting effects of various fatty acids in tall oil has led to a conclusion that the collecting power of fatty acids used in flotation increases with increasing unsaturation of the hydrocarbon chain, Linoleic acid was found to be an excellent collector for oxide minerals.

Jan 8, 1953

For the convenience of members who may be traveling from place to place, the Secretary has compiled a list of libraries or other places in the United States and foreign countries where MINING AND METALLURGY or the Transactions may be consulted. This list will be. sent to members if they so request. LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION TO MARCH, 1920

Jan 1, 1925

Discussion of the paper of Robert Franke, presented at the Butte meeting, August, 1913, and printed in Bulletin No. 79, July, 1913, pp. 1201 to 1205. ARTHUR 0. GATES, Lafayette, Ind. (communication to the Secretary*) :-In connection with the comparison of mechanical crushing efficiencies in Tables I and II of Mr. Franke's paper, I wish to suggest a somewhat simpler way of making this' comparison, based upon what the writer has called the "crushing-surface diagram," as published by him in the Engineering and Mining Journal for May 24, 1913. Such a diagram, based on the data given in Table II, is submitted herewith, Fig. 1, cumulative percentages being plotted as abscissas and reciprocals of diameters (theoretical mesh per inch). plotted as ordinates.. Such a diagram averages the diameters without calculation, and areas upon it are proportional to surface produced, and, in accordance with Rittinger's law, to energy spent on crushing alone.

Jan 11, 1913

By Y. P. Chugh, Rajiv Singh

This paper presents the feasibility analyses of terrace pit mining a single seam for depths beyond 33 m (110 feet) in a hypothetical model mine and at an operating mine in southern Illinois. One or two shovel- truck benches near the surface and a large dragline for the last bench are considered for overburden stripping in the proposed mining scheme. Mining and reclamation operations are integrated and reclamation efforts are minimized by proper spoiling techniques. The proposed mining scheme was optimized using the OPMHS (Open Pit Material Handling Simulator) model developed by Penn State. Equipment selection and economic analyses were also conducted using the simulation model. The effect of pertinent variables such as thickness of the coal seam, annual production, initial capital requirements, size of haul trucks, selling price of coal and expected rate of return were analyzed on the feasibility of terrace pit mining. Sensitivity analysis charts for the effect of these variables are presented in the paper.

Jan 1, 1983

By A. S. Richardson

THE design of mine airways receives, in general, very little engineering treatment. To a large extent this is, of course, due to the fact that information upon which to base calculations is seldom available in definite form. In many mines the extent of the workable deposits may not be known at the time an air course is planned, and the length of service is indeterminable. Volume of air required for ventilation may also increase with extension of the life of a property, and natural obstacles, such as heavy ground, often place limitations upon the size of opening that can be maintained. Perhaps a majority of the shafts used in ventilation of metal mines were originally intended as hoisting shafts, and many of the tunnels and cross-cuts similarly used, were also designed as haulage ways or for other operating purposes. Even when a shaft is sunk solely for ventilation, custom usually dictates a size and shape consistent with the type commonly used for ordinary operations, because experience has demonstrated it can be excavated and maintained. In fact it may not be very far wrong to say most ventilation openings were never made with any consideration as to economic design for such use. When an air course is required to pass air between different parts of mine workings under a fixed pressure, the size of opening required for a given volume of flow, is, of course, determined by the resistance factor of the air course. It is then impossible to proportion the opening with reference to economics of power consumption, and this paper is limited to the design of openings where ventilation pressure or power consumption may be varied for economic advantage.

Jan 2, 1926

By Edward Keller

Someone some time ago remarked that some chemists still insist on telling us how to determine copper by the electrolytic method. The writer must confess that he believes that everything is not known definitely as yet as to how the exact amount of copper is determined in such material as purest commercial electrolytic copper. Some of us are not yet convinced that the pure copper atom is at all times deposited from an acid solution and that no oxygen or hydrogen will, under certain conditions, accompany it. Difficulties with impurer material are frequent, but erroneous results are not always apparent, since these do not speak so readily for themselves as those in the first case. By this is meant that if a chemist finds 100 per cent. of copper in electrolytic copper it is pretty certain that he perceives the result to be wrong, while if he finds 0.1 per cent. of copper too much in a very impure material he is far more likely to be unconscious of his error. These, in a wide experience, are frequent happenings and the writer has always looked with interest to publications on this subject. In turn, he feels justified in giving to others a few of his own observations. Up to a few years ago there were two methods of electrolytic copper assay in technical use, which had in common, that the amount of copper deposited on the cathode did not exceed 2 g., and they differed in that, for the one a large sample1 (20 to 80 g.) was taken from the general sample by a splitting device, dissolved, and from the solution a small portion (to contain 1 or 2 g. of copper) measured out for the electrolytic deposition; in the other method the copper was determined, generally in 1-g. portions of the separated coarse and fine portions of the sample, all of which passed a 16 or 20-mesh screen, being accomplished by a 40-mesh screen,

Jan 1, 1914

By R. V. Ramani, Ish K. Chopra, Robert Stefanko

The results of a recent study on the influence of continuous and conventional mining techniques on the size consist and washability characteristics of coal are presented. Eight samples, four each from continuous and conventional mining sections, were collected. Each sample was screened in seven size fractions, and each size fraction was totally fractionated at five gravities. The data thus collected were statistically examined for the influence significance of mining techniques, size, and gravity on the quality of the mined product. The paper presents the sample collection method, data gathering and analysis procedures, and major conclusions. The study revealed that there are pronounced differences in the products from the two mining systems and that conventional mining yielded a better product in terms of size consist, yield, ash, and sulfur in both the raw and washed products. The results of the study are significant in regard to consideration of resource utilization and conservation, and environmental impacts.

Jan 1, 1976

By John R. Hutchins

1ms is a report of nickel (wire) oxidation studies designed to test the validity of Valensi's1 equation developed for the kinetics of a reaction controlled by diffusion in a continuously growing product layer on cylindrical surfaces. The equation is:

Jan 1, 1968

By Philip L. Collyer

A technique for evaluating the similarity of ore deposits is presented. A Q-mode cluster analysis is performed using information on tungsten mines in North America. This is a method of grouping several samples according to their similarity based on a simple matching coefficient. Tungsten mines are grouped or clustered on the basis of geologic variables. It is possible to interpret and evaluate different ore environments according to age, mineralogy, and other variables. It is well known that variable geologic conditions influence the occurrence of certain types of minerals. If one variable is responsible and identified, that variable can be searched for in exploration. If several interrelated variables are responsible for forming a favorable environment, then recognition and identification may be more difficult or completely masked. Therefore it is helpful in exporation to isolate and identify multiple interrelated variables which control the localization of mineral deposits. Cluster analysis is useful in mineral exploration where considerable amounts of data are available for analysis. Subtle relationships that might be overlooked because the data are voluminous can be isolated using this technique. Cluster analysis can be used to establish exploration prioriy in unknown areas on the basis of similarities to known metallogenetic provinces.

Jan 1, 1976

By D. M. Wade, F. F. Redfield

PRODUCTION at Aguilar started in 1936 and by 1942 the mine had reached a peak of 25,000 tons a month. Present production is only about 60 per cent of this capacity because of difficulties in railroad transportation and the rationing of fuel oil brought about by the war. In the early years, cut-and-fill stopes were tried, but square sets were found to be the most practical method in the southern section of the mine, where blocky, treacherous ground and greater mining widths are prevalent. Square sets and opencut mining were the rule until 1942, when it became increasingly difficult to get mine timber. The ore beds in the northern section of the mine were found amenable to cut-and-fill stoping as the rock was firmer and the veins narrower. At present 69 per cent of the ore comes from cut-and-fill stopes, 27 per cent from opencut, and only 4 per cent from square-set stopes. Massive galena and sphalerite with comparatively little quartzitic gangue constitutes the higher-grade ore. The gangue minerals that can be detected by eye in low-grade ore are rhodonite, wollastonite, and pyrrhotite. Wall rocks range from shale to quartzite, with occasionally a little limestone.

Jan 1, 1947