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By David A. Martin

Resource based companies have been inundated with changes in government tax legislation during the past few years. To cope, capital investment planning analysts have turned almost completely to computer simulation modeling to react quickly enough to determine the effect on their companies' major investment projects and on the projected financial picture of the companies. This paper will examine various royalty and tax structures as applied to coal, oil and gas, and minerals in the U.S. and Canada with particular emphasis on recent changes in the Canadian tax scene and their implications to capital project economic evaluation in other parts of the world.

Jan 1, 1977

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Jan 1, 1938

By William P. Blake

The phenomena of concentric arrangement of minerals in rock-masses, generally known as " orbicular structure," have of late received much attention from investigators. Lawson, of the University of California,' has described the orbicular gabbro at Dehesa, San Diego county, Cal. Kessler and Hamilton, of Stanford University, working independently upon the same subject, published their descriptions,2 giving also a list of many other localities in Europe and America where orbicular rocks are found, adding copious references to the literature of the subject.

Jan 1, 1906

Jan 1, 1879

By R. H. Eckhouse, M. R. Geer, H. F. Yancey, C. L. Allyn

Four coals were treated in the Humphreys spiral concentrator, and the products were examined by float-and-sink and screen-sizing tests to determine fundamental performance characteristics. The efficiency of the separation between coal and impurity was shown to be influenced greatly by particle size.

Jan 10, 1950

Jan 1, 1898

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Jan 1, 1938

By J. Brian Eby, T. I. Harkins

THIS paper outlines the geophysical investigation of the area covering the Darrow salt dome, Louisiana. Surveys with the refraction seismograph and torsion balance failed to disclose the dome, but reflection dip shooting was successful and was confirmed by later drilling.

Jan 1, 1942

Jan 2, 1951

By E. C. Weichel, J. H. Carpenter, J. C. Detweiler, J. L. Gillson, J. P. Wood

ILMENITE, rutile, zircon, and other heavy minerals are found in small amounts in the sand that covers most of Florida. Small enriched deposits occur on the beaches and coastal dunes. One beach deposit east of Jacksonville was worked during World War I and another near Vero Beach during World War 11. Both ceased operation when the resumption of imports reduced prices.

Jan 8, 1953

By P. F. Allen

With capacity of 51,000 tpd, the Morenci concentrator produces approximately 49,000 tons of tailing for final deposition. Disposal involves distrlbutlon of thickened tailing to dams in such a manner that solids can be used for dam construction and water can be impounded for reclamation. During early operation, although tonnage treated was lower, it was necessary to use orthodox disposal practices in the areas available for tailing. Trestles mounted on a series of dams, constructed of borrow material, carried the pipelines from which tailing were spigoted behind the dams. When adequate disposal areas were finally established, it became desirable to look for more efficient methods. The idea of placing the distribution pipe or manifold directly on the crest of the dam was advanced in 1945. After a period of testing, that procedure in modified form replaced the older trestle arrangement. Marked economies resulted, and time required to prepare dams for succeeding storage cycles was greatly reduced.

Jul 1, 1956

Jan 1, 1883

By F. R. Conley, D. A. Shock

Solution Mining or In Situ Mining has received increasing attention in the past few years because the method offers many attractive possibilities in improving the environmental impact of mining as well as making feasible the extraction of deeper, low value mineral reserves. This paper will present a brief discussion of the state-of- the-art in total solution, slurry removal and leach mining. As a specific example of utilizing the method, the uranium deposits of South Texas are a type of deposit which have been considered as being amenable to in situ leach mining. The parameters required to ascertain the amenability of such a deposit for in situ leaching will be presented. The hydrological factors which influence the production of the soluble uranium solutions and their displacement will be discussed. Mathematical models for various well configurations have been made and graphic representation will be presented to illustrate various production methods and the resultant hydrological consequences.

Jan 1, 1974

NEW MEMBERS The following list comprises the names of those persons who became members during the period July 10 to Aug. 10, 1915: Members ALBERTSON, MAURICE MERTON, Mine Surveyor, Mining Corporation of Canada, Cobalt, Ont., Canada. ARMSTRONG, GEORGE CHANDLER Mgr., Indian Refining Co., Lawrenceville, Ill. BARBER, MAX HAYDEN, Min. Engr Supt., Crosby Mine, Nashwauk, Minn. BARNESON, JOHN Merchant, 310 Sansome St., San Francisco, Cal. BENSEL, JOHN A., Cons. Engr 111 Broadway, New York, N. Y . BORGESON, ANSHELM CYRUS, fin. Engr Shenango Mule, Chisholm, Minn. BROOKS, CHARLES PETER, Min. Engr 228 Dooly Bldg., Salt, Lake City, Utah. BROWN, FRANK HAROLD, U'011',. Min. Engr., Federal Co., Inc., 50 Broad St., New York, N. Y. CLARK, DOUGLAS Kellogg, Idaho.

Jan 9, 1915

By Robert W. Hunt

Having had some twenty years' experience in trying to make good Bessemer steel rails, and now devoting my thoughts and energies to seeing that other people seek the same end, I venture to lay before the Institute some of the conclusions deduced from my practice and observation.

Jan 1, 1889

By Henry E. Colton

Very little information has been published concerning the Tennessee coal-field. The State never appropriated over $600 per annum for a geological survey, and that was discontinued about 1870. Yet even with that small sum Dr. J. M. Safford made a

Jan 1, 1886

By Evert Hoek

SYNOPSIS It can be shown that the properties of intact rock are relatively unimportant in rock slope stability and that failures are controlled by structural discontinuities such as bedding planes, joints and faults in the rock mass. The frequency, orientation and inclination of these discontinuities as well as their strength characteristics are important factors to be considered in any rock slope analysis and their influence will be demonstrated by means of a number of practical examples. Methods for determining the mechanical properties of discontinuities will be reviewed and the interpretation of the strength test results for use in stability computations will be discussed.

Jan 1, 1971

Jan 1, 1918

Jan 1, 1953

By Wilson Blake

As a part of a USBM-ASARCO cooperative rock-burst research program, a burstprone stope pillar at the Galena mine was successfully destressed. Destressing was accomplished by blasting a single line of long holes in the footwall of the vein. As a result of destressing, the pillar was fractured and softened; hence it yielded, releasing a large amount of stored elastic strain energy nonviolently. In addition, the high stress in the pillar was shifted out around the stope walls and in the sandfill. Both broad-band microseismic monitoring and seismic velocity surveys were used to evaluate the destressing test. The mechanics of destressing were determined by finite element computer model studies of destressing. Results of the field destressing test agreed remarkably well with the predicted results from the computer model.

Jan 1, 1973