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By Calvin C. Brown

A university is a place to build minds and develop leaders. It provides the tools necessary for the development of new ideas which come from the inquisitive mind and is one of the stepping stones to management responsibilities for the truly ambitious. However, it is not always a financially sound investment! Lately, there have been several articles published on the economic advantages of a college education. These articles tend to average wages together according to education and years of service. Their tabulations generally include the chairman of the board, various vice presidents and plant managers and do not reflect the achievement of the average graduate. They consistently fail to include an analysis of the investment a college education requires. In reality, the bright high school graduate would make more real money over a 20-year period if he went directly to work "on the hill" than he would if he graduated from college. Furthermore, he would find little difference between his wages and those of the college graduate in the period from 20-30 years after high school graduation.

Jan 1, 1971

By W. E. Anderson, T. M. Brady

As part of a larger study to identify factors influencing the practical operating life of wire rope used on large draglines in surface coal mining, field trips to operating surface coal mines were made during late 1975. Wire rope performance information was obtained from personnel at 13 mine sites west of the Appalachians. Seventeen pieces of equipment, utilizing bucket sizes ranging from 30 to 220 cu yd (23 to 168 m), were documented. Draglines at large US surface coal mines can be represented as 120 machines having 60-cu yd (46-m3) buckets, moving 1.8 x 10[9] cu yd (1.4 X 10[9] m3) of overburden during 6650 hours of productive availability per year. Based on the limited field study, the calculated downtime resulting from rope-related causes averages 105.6 hours per year for each typical 60-cu yd (43-m3) dragline. The total loss in production from this source alone is thereby estimated at about 25 X 10[6] cu yd (19 X 10[6] m3) annually.

Jan 11, 1979

By R. W. Raymond

I desire to call the attention of members of the Institute to a new method of plotting and determining faults in mineral deposits, suggested by Prof. Hanns Hoefer, lately of the Mining School of Przi-

Jan 1, 1882

Inflation, tight money and keen competition spur companies to consider advanced material handling systems capable of reducing cost per ton of moving ore, waste or men and supplies. Since transportation charges account for an average of about 25% of the total delivered price of a product, then this cost center may actually determine the economic value of a new deposit. This being so, it is interesting to note that of the 1.4 billion tons of revenue freight carried by all Class I carriers of the nation in 1967, over 247 million tons or 17.5% were industrial minerals or products dependent on industrial minerals, i.e., glass, gypsum board, brick, etc. Because most bulk commodities have a comparatively low market value and are usually classified for lower than normal freight rates, railroads rely on large volumes and better equipment utilization to effect an equitable return. It is for this reason that the unit and shuttle train concept came into being. The average rate per ton-mile of all materials hauled by rail in 1968 was 1.31 cents. The low rates existing for industrial minerals contributed to this low average as did unit and shuttle train rates.

Jan 10, 1969

By N. Brown

IT has been observed that a hexagonal-close-packed crystal will undergo the same macroscopic displacements as an isotropic material if the basal plane is perpendicular to the axis of twist.&apos; Other orientations may produce both bending and twisting, but this analysis will be confined to pure torsion of a right circular cylinder. The z axis, the axis of twist, and the specimen axis are coincident. The displacements are given by Uq = rz, Ur = Uz = 0 [1] where 4 is the angle of twist per unit length. This requires rotational slip, as discussed by Frank&apos; and Wilman, which may be observed readily. The relative rotation of adjoining slip planes is simply produced by a movement of a planar grid of screw dislocations."." The screw dislocations are of the same sign and they move radially inward. For hexagonal-close-packed metals, the grid is hexagonal and the screw dislocations lie in the < 2110 > directions. The displacement of a point is the resultant of two displacements produced by intersecting screws sweeping over the point. The dislocations must pass over the point (r, o) in such a manner that its resultant displacement corresponds to the observed macroscopic displacement. If 6&apos; is measured from the [1010] direction, then for 0 < ? < ~/3, only the [1210] and 121101 type screw dislocations are needed to produce the required displacement. If n1 screws of type [1210] and n2 of type [2110] pass over a point, then, in order that Ur = 0 n, sin ? - n2 sin (/3 — 6&apos;) = 0. [2] If the tangential displacement is to be independent of 0, then n1 cos ? + n2cos (/3 —?) = N [3] where N is independent of ? and thus depends only on r. Nb is the tangential displacement where b is the Burgers vector. Since U? is a linear function of r, then N must be a linear function of r. If a2 is the outer radius and a, is the inner radius to which the plastic deformation has extended, then N = Nm2 r-a1 [4] This function meets the conditions that at

Jan 1, 1956

By Wallace Ralston

The East Texas area includes the northeast 38 counties of the state of Texas. It covers all, and extends beyond, the borders of what is commonly described as the East Texas Basin. It is one of the most important oil and gas-producing areas of the Mid-Continent Province. It includes four important oil fields—Van, East Texas, Cayuga and Long Lake— and the recent extension of Rodessa field into Cass County, Texas, may prove to be of major size. Four commercial gas fields are in this area— Bethany, Waskom, Cayuga and Long Lake. Up to January, 1936, all of the oil has been produced from the Upper Cretaceous formations, and most of that from the basal member, the Woodbine sand. Gas is produced from both the Upper and Lower Cretaceous formations. Development in Fields East Texas Field.—This field continued to dominate the drilling and production situation throughout the United States. There were 4036 wells completed in this field during 1935; that is, 365 more wells than were completed during 1934. Drilling activity was due to close spacing of wells and the addition of 10,000 acres to the field. The field is now drilled to a density of one well to 6½ acres, which is certainly more wells than necessary for economic production of the field. The close spacing of wells is due mostly to the type of proration, which is per well allowable based on a potential test, and does not take acreage into consideration, and also to the numerous small acreage tracts such as town lots and excess strips. The field now has 19,519 producing wells. The allowable production for the field during 1935 was 161,118,659 bbl.; estimated production, including illegal or "hot oil," was 174,200,150. The illegal production of oil gradually decreased throughout the year, until an estimated low was reached of 20,500 bbl. daily during the months of November and December. The price of oil remained at $1.00 per barrel throughout the year. As stated, about 10,000 acres were added to the field during the year, making a total of 128,000 productive acres. There is a possibility that

Jan 1, 1936

By F. F. Schmidt, H. R. Ogden, E. S. Bartlett

ThE solubility of carbon in tantalum has been reported to be very low at temperatures below 1500 C,1&apos;2 increasing to at least 0.02 wt pctl at the eutectic temperature of 2800°C. The solubility limits at low temperatures were based on metallo-

Jan 1, 1963

By John T. Galey

The restrictions placed on drilling by the Federal Government, which caused a severe curtailment in activity at the beginning of the year, were relaxed somewhat so as to permit the drilling of one shallow† gas well per 40 acres. New wells numbering 574† were drilled for a combined depth of nearly 1,500,000 It., and of this number 131 were dry holes with a footage of slightly over 375,000. Inside locations account for the majority of these totals and the increasing demand for natural gas would normally have increased the number considerably, but many of the independent operators chose to ask for fewer exceptions to Order M-68 of the Office of Production Management, and consequently to curtail the number of wells drilled. Initial open flow of natural gas developed from all operations§ is over 230 million cu. ft. Nearly 191 million cu. ft. of this volume resulted from the 410 new gas wells drilled to horizons above the Lower Devonian, and the footage drilled in these wells accounts for approximately 93 per cent of the total. Shallow Development Oil.—Thirty oil, wells, with a total initial production of slightly over 152 bbl. and a footage of 50.000, were drilled during the § Including deepening wells previously drilled.

Jan 1, 1943

By John T. Galey

The restrictions placed on drilling by the Federal Government, which caused a severe curtailment in activity at the beginning of the year, were relaxed somewhat so as to permit the drilling of one shallow† gas well per 40 acres. New wells numbering 574† were drilled for a combined depth of nearly 1,500,000 It., and of this number 131 were dry holes with a footage of slightly over 375,000. Inside locations account for the majority of these totals and the increasing demand for natural gas would normally have increased the number considerably, but many of the independent operators chose to ask for fewer exceptions to Order M-68 of the Office of Production Management, and consequently to curtail the number of wells drilled. Initial open flow of natural gas developed from all operations§ is over 230 million cu. ft. Nearly 191 million cu. ft. of this volume resulted from the 410 new gas wells drilled to horizons above the Lower Devonian, and the footage drilled in these wells accounts for approximately 93 per cent of the total. Shallow Development Oil.—Thirty oil, wells, with a total initial production of slightly over 152 bbl. and a footage of 50.000, were drilled during the § Including deepening wells previously drilled.

Jan 1, 1943

By A. L. Hay

The Sydney coal field, the largest and most valuable in Nova Scotia, is situated on the northeastern coast of the Island of Cape Breton, extending from Mira Bay on the south to Cape Dauphin on the north, a distance of 30 miles, and has a general dip northeast under the sea. (Fig. 1. The field embraces the mining villages of Morien, Birchgrove and Reserve and the towns of Dominion, Glace Bay, Waterford and Sydney Mines. The city of Sydney is situated about midway between the northern and southern extremities of the field and on the western fringe of the productive coal measures. Sydney harbor crosses the coal field, cutting off direct rail connection between Sydney Mines and the greater part of the field to the southeast. (Fig. 2.) The coal measures are exposed in the cliffs on the coast line, which rise to an average height of 30 ft., and are almost continuous throughout the length of the field. The portion of the coal field under land forms a small segment of a circle, the greatest distance from the coast landwards is 9 miles, and it occupies an area of 200 sq. miles. The greatest distance developed seawards from the shore by mining operations is 2 miles. The strata maintain a regularity of dip at this distance, proving a submarine area of about 70 sq, miles. How much further the coal field extends seawards is unknown, but the indications are that it extends far beyond the present economical working limit and in all probability there is a vast submarine coal field. The productive coal measures are of Carboniferous age, these being underlain by beds of sandstone, locally classed as millstone grit, which define the southern limit of the field, while a spur of syenitic hills cuts off the coal-bearing strata on the north. Two main anticlinal folds having a general course easterly divide the field into three basins named from north to south: Sydney Mines-Lingan, Glace Bay and Morien. So far as the portion of the coal field already developed is concerned the general effect of these folds is to vary the direction and dip of the strata at different points of the several basins. The strata dip seawards at the average rate of 6 per cent. along the axes of the basins. On both sides of the several basins, the strata have a dip varying from 7 to 40

Jan 1, 1930

By Herbert H. Mellus

TODAY the tractor-drawn carryall scraper has a very important role in the Open Pit div. of Inspiration Consolidated Copper Co. Carryalls have already moved over 3 million tons of material at costs comparable to or lower than for conventional truck and shovel operation, and a major program of scraper stripping and ore production schedules has developed from early isolated scraper applications.

Jan 10, 1953

By J. Amanat, H. J. Siriwardane

A numerical procedure based on nonlinear finite element analysis has been developed for predicting subsidence profile over longwall mine panels. The developed procedure has been verified by comparing predictions with published field observations at several mine panels. This paper presents certain aspects of predicting subsidence profile over mine panels located in hilly terrain. Analysis of four such cases are presented herein.

Jan 1, 1984

By J. H. Wright

Longhole sublevel stopes excavate ore with which the production geologist has only remote contact; therefore, predicting grade and tonnage from such a stope can be a problem. However, the longholes themselves yield data that can be used to improve those predictions. Here, a radial distribution method of weighting sample data is discussed, which is useful in forecasting grade and tonnage from certain longhole sublevel stopes.

Jan 1, 1985

A High-speed Dilatometer and the Transformational Behavior of Six Steels in Cooling. By Arthur L. Christenson, Edward C. Nelson and Clarence E. Jackson. (With discussion).................................606 Dilatometric Studies of the Graphitization of Cast Iron. By N. A. Ziegler. With discussion) 627 An Interferometer Type of Dilatometer and Some Typical Results. By- L. &apos;4. WIlley and W. L. Fink. (With discussion).........................642 The meeting was held in the Pine Room of the Statler Hotel, Cleveland, Ohio, on Tuesday afternoon, October 17, 1944. The chairmen were F. M. Walters, Jr. and Howard Scott. Introduction F. M. Walters, Jr.—The principal advantages of the dilatometric method perhaps are two, as compared with the method of thermal analysis. One is that the dilatometric method can be applied with a large variety of rates of heating and cooling, whereas thermal analysis—that is, the study of the transformational characteristics by means of heat evolution—is limited to the rates of heating and cooling that reveal the evolution of heat. The dilatometer can be used for the study Of reactions at zero rates of heating and cooling; that is, isothermal reactions. As you will hear this afternoon, the rates have been pushed up as far as 500°C. a second. The other advantage is that the dilatometric method shows that a two-phase region is a two-phase region, whereas the thermal analysis merely reveals the temperature at which the rates of heat evolution are greatest.

Jan 1, 1945

By Tony B. Szwilski

A short study has been made of the underground mining potential in the Plains region, the Province of Alberta, Canada. Particular reference is made to the possible application of longwall mining: Presently underground mining is limited to small scale room-and- pillar methods. The problems anticipated with large scale mining at shallow depths (30 m) are examined. Production factors based upon longwall retreat mining utilizing shield supports are also considered.

Jan 1, 1981

By W. A. Hockings, G. W. Lower, K. A. Smith

The kinetics of dissolution of metallic copper in aqueous cupric ammonium carbonate solutions were investigated. The major variables studied were temperature, agitation, and the cupric, cuprous, ammonia and carbonate concentrations. The rates of copper dissolution from rotating discs were determined by measuring the weight loss. The dissolution rate increased with the square root of the disc rpm and doubled when the temperature was increased from 20°c to 40°C.

Jan 1, 1973

By T. W. Martin, T. J. Crocker, J. M. Goris

The current technology of large rock conveyors is reviewed. Based on this investigation two large rock conveyor concepts have been developed and a test facility investigation designed and fabricated. The USBM will test these concepts along with loading and transfer points for handling mine run rock material up to 1.5 m (4.9 ft) in size. An evaluation of open pit mining systems using large rock conveyors documents substantial cost savings when compared to truck haulage.

Jan 1, 1983

By David H. Carlson, John H. Johnson

The paper presents background information, a description of mine characteristics that affect air monitoring techniques, and a review of Portable measurement techniques and instruments for gas and particulate matter sampling. A general review of the laboratory and field research being conducted at Michigan Technological University in the area of diesel emissions is presented. The facilities involved with this research are also described. These are the experimental mine, the diesel dilution tunnel test cell, the mine air monitoring lab (MAML), portable instruments, and the production mines used.

Jan 1, 1982

The surface area that mining requires is a minuscule fraction of the total land mass of the United States, according to the US Bureau of Mines&apos; latest report "Land Utilization and Reclamation in the Mining Industry, 1930-71." During the 42-year period from 1930 to 1971, the mining industry utilized 3.65 million acres-only 0.16% of a total 2.27 billion acres of land-and reclaimed 1.46 mil- lion acres, or 40% of what it used. Which leaves, as still unreclaimed, 0.096% of the nation&apos;s total land mass.

Jan 10, 1974

By K. H. Nimerick, G. P. Laflin

Laboratory data and field tests indicate that substantial losses of valuable coal can be caused by wind erosion. Wind tunnel tests show the effects of wind velocity and particle sizing on the amount of coal lost while in transit. Different coals were evaluated to determine the variables associated with wind erosion. The erosion losses can be substantially reduced by using a binder, or crusting agent, to consolidate the surfaces of the coal into a solid mass which resists erosion. This not only reduces economic loss but minimizes pollution.

Jan 8, 1979