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By C. R. Boyd

Without attempting to do more than give a preliminary or skeleton report upon the geology and minerals of Southwestern Virginia at this time, I am led to hope that the great commercial importance of the sixty miles of cross-section here crudely treated of

By John A. Oberteuffer, Ionel Wechsler

High gradient magnetic separation, first introduced in 1968 as a means for the removal of very fine magnetic contaminants from clay, is no longer a new technology. Applications to a number of solid-solid and solid-fluid separation problems are now being exploited. Recent pilot tests and full-scale industrial installations of high gradient magnetic separators and filters have established their commercial viability and have demonstrated their superiority both in efficiency and cost effectiveness to conventional prior-art methods for water treatment and mineral processing. In high gradient magnetic separators, the magnetic trapping force for fine, even weakly magnetic particles is greatly increased over those available in previous magnetic separators. These very strong trapping forces are created on the edges of fine filamentary ferro- magnetic materials in the presence of a strong background magnetic field. In the basic cyclic high gradient magnetic separator, particles are trapped in the filamentary matrix until it is loaded, at which point the magnetic field is turned off, and the filter is back- flushed. Applications of cyclic high gradient magnetic filtration for water treatment include filtration of waste and process waters in steel mills. Treatment of hot rolling mill scale pit effluent and cold rolling mill emulsion has been successfully tested, and 2-meter diameter SALA-HGMF® magnetic filters have been installed at Japanese steel companies for the treatment of recirculating scrubber waters in a de-gas- sing system. A second major application in water treatment is for the polishing of recirculating waters in power and steam generating systems. High gradient magnetic filters can operate under conditions of

Jan 1, 1980

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Jan 1, 1938

Jan 1, 1967

By Tomoyuki Moritani, Atsuyuki Mizuno

A concentration of manganese nodule varies areally from 0 to 30 kg/m2 in the central-eastern deep sea bottom of Central Pacific Basin with depth of 5,600-5,900m, but generally it is low, mostly of the abundance order from 0 to less than some kilograms per square metres through the bottom. A high concentration over about l0kg/m is localized to the northwestern basin, besides "St. 414 Deep Sea Hill" and “GH 76-1 Trought”, and also it is likely related with the substratum of deep sea clay. Nodules are tentatively classified into nine types of Sr, SPr, SEr, Db, Ss/SPs, ISs, IDPs and V, in terms of morphology and surface feature. The types may be related with internal structure, nuculeus, mineral composition, chemical composition, occurrence and areal distribution, and might have resulted from various environmental factors of nodule genesis. The abundance of nodule at each station shows the interesting relation with acoustic records by 3.5KHz and seismic reflection profilings. In both the records, thick transparent layer over about 45m thick yield neither any nor significant amount of nodule. The layer less than 45m relates with abundant nodules up to 30kg/m2, though it yield also very little nodule in some cases. The relation suggests that the formation of nodule most likely could be related with the accumulation rate of the post-middle Eocene sedimentary sequence to some extent and also with other controlling factors. The relation can lead us to the tentative delineation of distribution of nodule deposits in the area. The comparative-consideration with the deposits in GH 74-5 area, just east- ward of the present area, shows the areal peculiarity of nodule genesis in deep sea bottom. The results of chemical analyses will be discussed elsewhere.

Jan 1, 1976

A. SILVERMAN,* Pittsburgh, Pa.-Prof. Richards has described a very interesting process. In addition to the method described, electroplating and a number of other processes have been used. In one, the two metals were heated and united under hydraulic pressure; in a second, the steel was coated with an alloy, brass for example, and the molten copper cast around this. The process that I would like to bring to the attention of the metallurgists present consists simply of pouring molten copper, brass, or cupronickel around a clean red-hot steel billet. 'It is covered by the Roth patents. The 8-in. cylindrical billet containing about 70 per cent. steel (core) and 30 per cent. copper is hot drawn or rolled until several inches in diameter and afterward cold drawn or rolled to rod, wire of any desired diameter, or sheet. The wire is used for electrical conduits where conductivity and high tensile strength are required, also for the manufacture of cables and screen cloth. The sheet is employed for the manufacture of spouting, molding, shells, etc. The last application is particularly interesting. In testing rifle cartridges, which usually contain lead-filled copper noses, pine boards 1 in. thick, covered with ¼ -in. rawhide, are placed 1 ft. apart. The value of the cartridge depends on the number of boards penetrated by .the bullet. In government tests made with copper-coated steel noses (15 per cent. copper on either side of the steel) the penetrating power was found to be approximately double that of pure copper noses. The advantage of copper-coated steel over cupronickel lies in the fact that the- former does not require any special heat treatment during the punching. Rifle cartridges were prepared from copper-coated steel in a number of government arsenals. The value of the combination was attested by the awarding of a contract for the construction of a $3,300,000 plant. Unfortunately, the contract was signed on the day preceding the signing of. the armistice and was cancelled several days later. Tests were conducted for about 1 yr. before the contract was awarded to determine the value of this combination of metals. Since the war a number of cartridge and shell manufacturers have signified their intention of using copper-coated steel.

Jan 4, 1919

By J. Kostuik, M. J. de Bastiani

The method of mining the uranium orebody at Denison mine in the Elliot Lake district of Ontario is discussed. Details of the development of haulage-ways and rooms are giuen, as well as methods of ore haulage. The milling and beneficiation stages are noted briefly. Located in the Elliot Lake mining district of Canada, the Denison mine lies between Sudbury to the east and Sault Ste. Marie to the west, Fig. 1. This area is overlain by Huronian sediments filling a basin in the Keewatin basement complex. Subsequent folding of these sediments developed a synclinal structure, known locally as the Quirke Lake Trough, which forms the northern portion of the now famous big Z structure, the geological trademark of this region. Plunging to the west and extending nine miles from the granite outcropping in the north to the Keewatin lava contact to the south, the syncline has dips of 10" to 45" on the north limb and 10" to 20" on the south limb, Fig. 2. The Denison orebody, located on the north limb of the syncline, lies between 800 and 3000 ft below the surface. The main ore zone is within 50 ft of the Missisagi-Keewatin contact (see Fig. 3), and it varies in thickness from 6 to 32 ft. This ore zone has a composite dip of 19" to the south and is composed primarily of two pyritized conglomerate beds separated by a band of pebbly quartzite stratum. The upper conglomerate bed of the main zone varies from 2 to 15 ft in thickness, while the lower conglomerate varies from 2 to 12 ft. Over extended areas, mining is carried out over the entire section comprising the two conglomerate layers and intercalated quartzite; in other areas, the conglomerates are selectively mined, depending on the thickness of the quartz-ite. The ore zone contains approximately 6 pct sulfides and 80 pct silica. The predominant uranium-bear ing minerals are brannerite, uraninite, and an unidentified mineral (probably thucolite). Some of the uneconomic metallic minerals identified to date are pyrite, pyrrhotite, and chalcopyrite. MINE LAYOUT Shafts: Underground exploration and development (Fig. 4) were performed through two shafts 1/2 mile apart. The No. 1 shaft, sunk to a depth of 1856 ft with the main station established at the 1600-ft ore level, is a 250-sq ft, 5-compartment shaft capable of handling 4500 tpd. Two 5x5-1/2-ft compartments serviced by a 12-ft diam double-drum hoist, are used for hoisting 190-cu-ft bottom-dump skips in balance. A 30-man cage, offset by a counterbalance, operates within a 5-1/2x11-1/2-ft compartment. The fifth compartment is used as a manway, pipe, and cable-way. This shaft is also provided with an intermediate pumping station used during the initial mining phase as well as loading-pocket and spill-pocket installations and pumping facilities. The 480-sq ft No. 2 shaft, located down-dip from No. 1 shaft, has a 2776-ft depth. Serving as the main hoisting shaft with a maximum capacity of 9000 tpd, it has eight compartments, four of which are used for hoisting ore in 10-ton capacity bottom-dump skips. These four compartments, measuring 5x6-ft in section, are serviced by two 12-ft diam double-drum semi-automatic hoists. A 50-man cage is operated in a 15x8-ft compartment, and it is counterbalanced by a 12-ton weight. Two compartments are used for ventilation, manway, electric cables, and pipes. A station was constructed at the 1325-ft horizon of the No. 2 shaft for relay pumping. The main sta-

Jan 1, 1961

By A. S. Richardson

THe conditions that make necessary the mechanical ventilation of the Butte mines of the Anaconda Copper Mining Go. are due to a number of causes, all of which are incidental to the depth at which mining operations are now carried on, The main object to be accomplished, of course, is the reduction of the temperature and humidity of the air in the working places. Ventilation fans, both surface and underground, have been used for many years, but increasing depth has made the problem much more difficult. Further improvement in both ventilation equipment and methods, therefore, became necessary; and it is the purpose of this paper to describe the work planned and done under the improvement program. The mines of the district have been frequently described in various technical publications, so a description is unnecessary here. From a mine-ventilation viewpoint, compared with coal-mine ventilation systems, the problem is complicated by the fact that the workings to be ventilated are situated on a large number of steeply dipping veins which frequently intersect and are faulted, and also by the fact that the extent, or existence, of orebodies is not definitely known in advance of actual development work. For these reasons ventilation work cannot be planned in advance of actual operations, nor can such regular systems of ventilation as are used in working the more uniform and continuous bodies of coal be developed. When operations are conducted at a normal rate, about 10,000 miners are employed on two shifts, so that about 5000 men will be underground at one time. But as ventilation is necessary to reduce high temperature and humidity due, mainly, to natural causes, the quantity of air per man per minute is not a governing consideration in determining ventilation requirements. Most important among the numerous sources of heat and humidity in the mines are: heat generated during decay of mine timber; heat and humidity given off by mine rock and water; heat generated by oxidation of sulfide minerals; heat given off by electrical equipment; heat generated by mine fires (in certain localities).

Jan 1, 1923

PENNSYLVANIA ANTHRACITE LOCAL SECTION On Saturday evening, Jan. 31, 1914, about 40 members of the Institute met at the Hotel Sterling, Wilkes Barre, Pa., for the purpose of discussing plans for the formation of a local section in the Pennsylvania anthracite region. President Rand; Prof. Joseph W. Richards, of the Board of Directors; Dr. H. M. Chance, Chairman of the Committee on Coal and Coke, and Secretary Stoughton were among the guests present. R. V. Norris acted as Master of Ceremonies, and the arrangements were all made in advance by a Committee under the leadership of Charles Enzian, to whom an enthusiastic vote of thanks was accorded at the dinner. An address was made by President Rand, followed by .Professor Richards, who outlined the procedure necessary for the formation of a Local Section. Addresses were then made by W. J. Richards, F. W. Chase,. C. F. Huber, R. J. Foster, F. A. Hill, H. M. Chance, Bradley Stoughton, and others, after which a rising vote was taken, and it was unanimously decided to petition the Board of. Directors for the establishment of the Pennsylvania -Anthracite Local Section. More than the required number of members then signed -the petition, and President Rand announced the appointment of a Committee to organize the Section and arrange for a meeting in accordance with their By-Laws, consisting of R. V. Norris, W. J. Richards, R. J. Foster, Edwin Ludlow, C. F. Huber, Charles Enzian, Douglas Bunting, F. A. Hill, and J. M. Humphrey.

Jan 2, 1914

By C. Alstetter, V. Kerlins

By using alloys with subzero Ms temperatures, this investigation demonstrates that the amount of decomposition of martensite during the quench from austenite may be considerable and especially so in specimens of large cross -sections and high Ms temperatures. The activation energy for decomposition as measured dilutometrically is PREVTOUS investigations of the initial decomposition of Fe-C system martensite have invariably been limited to alloys having M, temperatures above a function of the amount of transformation which has taken place. The amount of transformation is a linear finction of log time. A correction term to the activation energy is derived for dilatometric measurements in which no end-point of the transformation is detected. room temperature. In such alloys the martensite is tempered during the quench to an extent dictated by the quench rate and temperature of formation. This tempering, called quench-tempering, Q-tempering, self-tempering, or auto-tempering, although frequently acknowledged, has not been studied or treated quantitatively. To do so one should obtain absolutely untempered martensite and study its decomposition. This as-formed martensite could be obtained either by extremely rapid quenching, requiring very thin specimens, or by lowering the martensite formation temperature range. The second alternative is more effective, because

Jan 1, 1963

By David B. Reger

Wildcat drilling for new supplies of gas and the expansion of previously discovered oil and gas pools were the principal petroleum activities in West Virginia .during 1942. Much of the new gas exploration is still uncompleted and still indecisive but various wildcats made substantial extensions to existing pools. Out of 53 wildcats drilled 27 resulted in commercial gas and 6 in commercial oil. Four of the oil discoveries also had commercial gas. No strictly new pools of oil or gas can safely be described as discovered but several scattered oil and gas wells previously drilled have been confirmed as the openers of definite pools; also, various completions closed wide gaps between apparent gas pools already discovered. The proved oil territory of the state was increased about 4850 acres and the proved gas territory about 51,000 acres. The new proved oil reserves should about balance withdrawals and the new gas may represent a substantial increase. Aside from the drilling in four rather lively pools, oil activity was slight because of unfavorable operating conditions and prices. Gas drilling also declined for reasons beyond the control of the operators. The account of operations, as gathered from trade journals and other reporting services, shows that 797 new wells were drilled, providing 119 new oil wells with 2762 bbl. of daily new production; 536 new gas wells with 1,228,501,000 CU. ft. of daily open flow: and 142 dry holes. Also... 76 old wells were drilled to deeper sands, with 71 bbl. and 26,034,000 cu, ft. of added production. On the new wells the oil average was 23.21 bbl. per well per day; and the gas average was 2,270,406 CU. ft. per well per day. On new wells the ratio of dry holes to completions was 17.82 per cent. On deeper drilling the ratio of failures was 21.05 per cent. Production of oil for the year was estimated by the Oil ad Gas Journal as 3,492,000 bbl., as compared with 3,378,000 bbl. in 1941. Production of natural gas for the year is estimated by the author as 220,000,000,000 cu. ft., as compared with the U. S. Bureau of Mines final figures of 207,000,000,000 cu. ft.* in 1941. General State op Industry Leasing of wildcat acreage increased considerably. The total land of all classes under lease may now exceed 5,000,000 acres. Taking into consideration completions, abandonments and corrected figures or estimates, Table I shows cumulative and late annual statistics. New Pools and Extensions Table 2 shows the principal areas of drilling activity during 1942. Various consolidations of territory, hitherto treated as separate pools, have been made. in addition to these active pools, extensive drilling was done in numerous other areas where pool boundaries can hardly be defined. Summary or Exploration Table 3 gives a summary of important wildcat or exploratory wells drilled during

Jan 1, 1943

By E. De Goyler

Volcanic origin was among the first of the theories advanced to account for the occurrence of the salt domes of the Gulf coastal plain, northern Louisiana, and eastern Texas, and it is still being re-stated in various forms by the most recent contributors to our knowledge of the geology of such deposits. Argument has been largely by analogy and attention has repeatedly been called to the Mexican oil fields, particularly those of the Tampico-Tuxpam region, because of the occurrence of oil in close proximity to volcanic plugs in those fields, an occurrence supposed to have some resemblance to the common occurrence of oil in the salt domes of the United States. The author, having spent several months of the past year in a general study of salt domes and in a detailed study of certain domes in the United States, and having been acquainted for some time with the exploration of similar domes in the Isthmus of Tehuantepec region, Mexico, and with the general geology of the Tampico-Tuxpam region, Mexico, has reviewed the various theories of volcanic origin for salt domes which have been advanced to the present time. The purpose of this paper is to present such review and to discuss the supposed Mexican analogy. Review of Volcanic Theory R. Thomassyl who had visited the Five Islands of Louisiana between 1857 and 1859, in 1860 described them with some care, noting their distinct character, alignment, and similarity, and ascribing to them a volcanic origin. He regarded them as being akin to the mud lumps in the delta of the Mississippi and was impressed by their symmetry and by the ponds or lakes which occur on several of the islands and which he regarded

Jan 1, 1920

By R. F. Campell, W. L. Jensen

IT is not uncommon for martensitic high carbon steels having a coarse austenite grain size to exhibit microcracks when polished and etched and examined with a microscope, as described by Davenport, Roff, and Bain.' Whether such cracks exist before etching or are the result of acid attack during etching has been debated from time to time. Fig. 1 illustrates the effect of electrolytic polishing, mechanical polishing and etching subsequent to each polish on microcracks produced by oil quenching from 1800°F a steel containing 1.14 pct C, 0.23 pct Mn, 0.33 pct Si, and 0.45 pct Mo. The austenite grain size was 3-4 on the ASTM scale. Grinding on lead laps followed by either electrolytic polishing with acetic anhydride-perchloric acid solution' or mechanical polishing with Linde "B" alumina on "microcloth" (sometimes referred to as Gamal cloth) revealed microcracks without conventional etching, as shown in Fig. la and b, respectively. These same fields, after subsequent etching with saturated picral, are shown in Fig. lc and d, and the cracks are seen to be typical microcracks; moreover, the cracks appear to be broader and longer than before etching. Although the microcracks were revealed by electrolytic polishing alone, the possibility of acid attack was present; however, the mechanical polish was accomplished without any intermediate etching to remove disturbed metal, hence this is regarded as definite evidence that microcracks are present before etching.

Jan 1, 1954

By Michael D. Loy

While the coal industry in general has been slow in accepting automation, the last few years have seen a myriad of products developed by the private sector. These packages run the full gamut from sophisticated geological information systems to line entry discounted cash flow analyses. This paper is an attempt to unravel the confusion that may exist about mining software. Discussions will highlight major differences between software products (such as block vs. grid models, prefeasibility programs vs. Monte Carlo analyses), briefly discuss known vendors, list known package features and touch on hardware requirements. The paper also focuses on the costs of automation (both software and hardware), possible trade-offs, advantages to in-house systems (vs. timesharing), a recommended review/selection process (including suggested RFP format), a test case procedure, when to bring in a consultant, and staffing considerations.

Jan 1, 1983

Vol. 54 will be sent about February 1 to members who have paid their dues for the current year. Members who do not receive copies within a reasonable time are asked to notify the Secretary.

Jan 2, 1917

By Henry Engelmann

ORES are generally found in the mines mixed with more or less base matter, which renders their treatment by smelting or milling unnecessarily costly. They have to be sorted. Those of a higher grade remain often mixed with substances which might, with hardly a loss of metal and at small expense, be removed by dressing machinery, and a concentrated and purified ore thus obtained, which would bring a far higher price, because it can be reduced by cheaper methods, and, at any rate, at less expense, besides affording a saving of transportation, which in our territories is often an item of no small magnitude. The ores of a lower grade have often to be

Jan 1, 1874

COUNCIL OF EDUCATION OF AIME (Formerly Mineral Industry Education Division) Established as a Division January 15, 1932 Established as a Council February 26, 1957 John C Calhoun, Jr, Chairman 0 Cutler Shepard, Vice-Chairman Thomas A Read, Secretary-Treasurer Dept of Mining & Metallurgical Engrg University of Illinois Urbana, Illinois COUNCIL OF ECONOMICS OF AIME (Formerly Mineral Economics Division) Established as a Division December 15, 1948 Established as a Council February 26, 1957 Louis C Raymond, Chairman Lorin A Cranson, Vice-Chairman Henry T Mudd, Vice-Chairman Adam K Stricker, Jr, Vice-Chairman Paul F Yopes, Secretary-Treasurer U S Bureau of Mines Albany, Oregon

Jan 1, 1957

By V. Rajaram, I. P. Nielsen, H. D. Raymond

The Parachute Creek member of the Green River formation in the Piceance Basin, Colorado, contains vast reserves of oil shale, nahcolite, dawsonite, and other accessory minerals. The dry alkali process of sulfur dioxide removal using nahcolite (naturally occurring sodium bicarbonate) has great potential. A room and pillar mining scheme has been designed to extract a nahcolite zone occurring at a depth of 472 m, from the lease application area of the Yankee Gulch joint venture. Geotechnical parameters affecting mine design will be discussed. A preliminary development plan for mining at the rate of 1000 t/d will be described in detail.

Jan 12, 1979

Jan 1, 1919

Jan 1, 1940