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By A. Hamilton Garner

Northern Venezuela has been divided into three provinces, as follows: The Llanos, the Andean, and the Maracaibo Basin and Falcon. The first and third are large sedimentary basins offering, possibilities for oil accumulations. Oil is known to occur in many formations ranging in age from Cretaceous to Quaternary. The most prolific source of oil is probably the Cretaceous shales and limestones, from which the oil appears to have migrated into overlying porous beds. Faulting or fracturing, folding, and porosity are governing factors in the localization of commercial deposits. THE occurrence of oil seepages in Venezuela has been known since the early days of Spanish occupation. It was not until 1912, however, that any serious exploration work was undertaken. In that year, the Caribbean Petroleum Co., then a subsidiary of the General Asphalt Co., employed a large staff of geologists to make a systematic survey, of large areas in eastern and western Venezuela, selecting the most, desirable localities out of the immense area covered by the Valladares concession. This preliminary work was completed in the fall of 1913, and in February, 1914, the company completed its first commercial well at Mene Grande. Development work has progressed slowly, for various reasons, but petroleum in quantity has been encountered in nine widely separated localities. The Mene Grande field has been put on a producing basis and approximately 4,000,000 bbl. of oil are being shipped annually. Increasing quantities of oil are now being drawn from El Mene and La Rosa. In the light of these developments, the world's need for oil reserves, and the proximity of Venezuela to the United States, American capital is being attracted more and more to Venezuela. Although considerable careful geological work has been done in Venezuela by the various oil companies now operating, most of the data is. buried in the company,, files, and the published literature has been extremely meager. The most valuable contribution to date has been a map and report by Jahn, which, as it was printed in Spanish, is not. generally available to the American oil public.

Jan 10, 1924

By C. H. Snyder

The paper deals with details of construction of the Colmol, including improvements in design that will be incorporated in new models. These improvements are results of problems encountered and worked out in experimental operation with the unit. Also included is a descriptive plan of operating where roof and air conditions are of the worst. A summary of production results from the machine is presented.

Jan 6, 1950

By John Birkinbine

The following data concerning the general dimensions and district-location of the blast-furnaces of the United States are intended to supplement a paper of similar title, which appears in volume xiv., pages 561 to 577, of the Transactions, and bring the record to the end of the calendar year 1886. The reasons for presenting the figures at so short an interval since the former paper are that the American Iron and Steel Association has lately issued a new directory of iron and steel works (edition of 1886) from which many of the plants which have been inactive are omitted and new industries added, to such an extent as to materially affect the figures presented in the first paper; and also that the improvement in business has encouraged a production of pig-iron in 1886 in excess of any previous outputs, and the results obtained in the industry at large as well as at individual plants form a better index of what the American furnaces can accomplish than those heretofore presented. The statement will not be extended beyond the production of pigiron, although it could well be made to include the manufactured iron and steel; and while the data given have been verified as far as possible up to the close of the year 1886, no attempt, except in special cases, has been made to note the changes which have taken place since that time—changes which within the next twelvemouth will affect some of the figures here presented. At the close of the year 1886 there were 579 blast-furnaces reported on the active list—an apparent decrease, as compared with my former paper, of 97 stacks; but this was not an actual decrease, since most of the furnaces dropped from the Directory were those which, owing to location, inefficient equipment, or fake of ore-supplies, etc., were considered likely to remain inactive, although a number of them will possibly be temporarily put into blast with iron advancing in price. On the other hand the new plants added

Jan 1, 1887

By C. Gutiérrez

Flotation and adsorption studies of ilmenite with technical oleic acid, pure oleic acid, and mixtures of each of them with n-hexadecane have been conducted. From them it is concluded that the depression of ilmenite caused by a too long conditioning time is due to adsorption of the collector onto the fines produced by attrition in the conditioning cell, and that fuel oil is necessary for economic flotation of non-deslimed ilmenite ore. This beneficial effect of fuel oil is attributed to van der Waals forces, of the hydro-carbon chains.

Jan 1, 1978

By George M. Schwartz, Ian L. Reid

THE Soudan mine in the Vermilion district of northeastern Minnesota is the oldest iron mine in the state. It has shipped ore every year since 1884 and still contributes a yearly quota of high grade lump ore. No comprehensive report on the Vermilion iron-bearing district has appeared since Clements' monograph,' but Gruner2 discussed the possible origin of the ores in 1926, 1930, and 1932, and recently Reid and Hustad have added data on mining and geology .3, 4 For many years geologists of the Oliver Iron Mining Div., U. S. Steel Corp., have kept up to date a series of plans and vertical sections of the Soudan mine. In connection with mine operation considerable diamond drilling has been done, and this, together with the mine openings, has permitted a reasonably accurate picture of the structure of the orebodies and wall rocks. It has long been evident to geologists familiar with the mine that the ores were not a result of weathering, a point emphasized by Gruner in 1926 and 1930. As the deeper orebodies were developed it also became clear that replacement had played an important part in their development. In recent years it has been recognized that other iron ores were formed by replacement, as Roberts and Bartly5 have argued strongly for the deposits at Steep Rock Lake. On the basis of these facts G. M. Schwartz suggested to members of the Oliver staff that it would be desirable to study the evidence of replacement, particularly the possible alteration of the wall rock which would be expected if the replacement was a result of hypogene solutions. Rock Formations: The formations directly involved in the iron orebodies of the Soudan mine are few though far from simple. The country rock is largely the Ely greenstone of Keewatin age consisting of a mass of metamorphosed lava flows, tuffs, and intrusives which have been more or less altered by hydrothermal solutions. The predominant rock is chlorite schist. Interbedded with the original flows and tuffs are a series of beds and lenses of jasper to which the name Soudan formation has been applied. In the Vermilion district the term jaspilite has been used for interbanded jasper and hematite. According to modern usage these jasper or jaspilite beds do not comprise a formation separate from the Ely greenstone, inasmuch as the beds of jasper are interbedded with the flows and tuffs of the upper part of the greenstone. It would more nearly accord with modern usage to consider the Soudan beds a member of the upper part of the Ely formation. Because of incomplete rock exposure and exploration the number of interbedded jaspilite beds is unknown. In the mine, however, as many as nine major beds of jasper are known on a cross-section of one limb of the syncline, with an equal number on the other limb. In addition diamond drill cores show beds of greenstone down to half an inch in thickness. The thin beds are probably always tuffs. Structure: Rock structure in the Soudan area is complex, and because there are no recognizable horizons within the greenstone it is extremely difficult to work out the details. Generally speaking, the major regional structure is an anticlinorium, the axis trending east-west, with a westerly pitch. The Soudan mine is related to a synclinal structure on the north limb of the anticline about a mile from the west nose of the folded iron formation. The general structure at the mine is that of a closely folded minor syncline on the major regional anticline. A cross fault has dropped the east side so that the bottom of the syncline has not been reached, whereas to the west it is well shown by the mine openings and diamond drill exploration. Throughout the mine the beds of jasper, and ore-bodies that have replaced the jasper, normally dip northward at angles of 80" or steeper. In detail the jasper beds are extremely folded, probably as a result of deformation while they were still relatively unconsolidated. Orebodies: Ore in the Soudan mine is mainly a hard, dense, bluish hematite. Locally ore has been brecciated and cemented by quartz. The vugs commonly occurring near the borders of orebodies are lined with quartz crystals. They seem to have formed as part of the ore-forming process and are evidence that no folding or compression of the ore has taken place. The orebodies are numerous, varying greatly in size. Many lenses of high grade hematite are too small to be mined. Some of the larger orebodies have been followed vertically for as much as 2500 ft and horizontally up to 1500 ft. The large ore-bodies are extremely irregular in outline in the plane of the beds of jaspilite. In width they are more regular, as they are strictly governed by the width of the jaspilite beds and the greenstone wall rock, which seems to have resisted replacement by hematite. At many places the orebodies replace the jaspilite completely and have a footwall and hanging wall of greenstone. At other places either one or both walls may be jaspilite. Geologists who have studied the orebodies in recent years agree that evidence for the replacement origin of the hematite bodies seems conclusive. AS noted above, many of the orebodies replace jaspilite beds from wall to wall with no evidence whatever of compaction. The replacement origin is also supported by details of the banding which is characteristic of the

Jan 1, 1956

By R. D. Reiswig, D. J. Mack

THE use of pyrophoric alloys in ignition devices dates back more than fifty years to a German patent granted to Carl Auer von Welsbach in 1903.' This patent named a composition essentially the same as that used in most present-day cigarette lighter "flints:" 70 pct mischmetal, 30 pct Fe, referred to here as "Auer alloy." Among the few current exceptions to this composition are those "flints" based on titanium or zirconium. The rare-earth metals of which mischmetal is composed are so similar chemically and physically remarkable similarity in their alloying behaviors would be expected. Comparison of the binary phase diagrams2 of these elements with nonrare-earth metals shows that this is true to a striking degree, so much so, in fact, that it appears that a mixture of these elements may be treated as a single component of alloys without fear of serious error. In considering alloys containing mischmetal, therefore, the mixture of rare-earth elements will be referred to merely as "cerium," the predominant element in mischmetal. In polishing cerium alloys for metallographic examination, it was soon discovered that aqueous polishing media were highly corrosive. Free cerium in the alloys acts similarly to calcium (though not quite so rapidly) in evolving bubbles of hydrogen at the metal-water interface; thus, special metallographic techniques are required. The simplest polishing technique found to be satisfactory consisted of slow hand grinding on dry emery papers through

Jan 1, 1956

By David A. Summers, Clark R. Barker, Marian Mazurkiewicz

In May 1975 the U.S. Bureau of Mines contracted with the University of Missouri-Rolla, Rock Mechanics and Explosives Research Center to develop a Hydrominer modification to a longwall shearer unit, wherein the rotating pick-laced drums and connecting gear drives are replaced by a water jet cutting ahead.1 The concept of the water jet cutting head is based on using the high localized energy of the water jets to isolate a slice of coal by cutting a slot under, at the back of, and at the top of the web. The plow blade of the head then advances into the cut and wedges the coal cantilever over onto the conveyor (Fig. 1).

Jan 4, 1978

Jan 1, 1939

By B. K. Parekh, W. M. Goldberger

A novel process is proposed for continuous removal of ash and unreacted solids which become suspended in the oils obtained during coal liquefaction. The proposed method uses water in direct contact with the oil under conditions which cause the suspended residue solids to transfer from the oil to the water phase. Separation of the phases yields a product oil essentially free of suspended solids. The water is cooled, clarified or filtered by conventional low-cost systems, and recirculated. The paper describes experimental work leading to development of the novel concept and includes the result of batch experiments that establish the feasibility of the process.

Jan 1, 1980

Jan 1, 1939

By J. A. Porter

In offering some data relative to this property, and the treatment of its ores, it is proper to say that a purely scientific article has not been attempted. It is hoped, however, that the economic conditions presented may be of interest to the members of the Institute, and that a discussion upon the concentration of the ore may throw some light upon a very unsatisfactory part of the work. The Smuggler-Union mines are located at the head of the San Miguel river, just south of the water-shed between Ouray and Telluride. The latter town, reached by the Denver and Rio Grande railway, is most picturesquely situated, at ail altitude of 8500 feet, in a narrow valley, the lower portion of which exposes only the sedimentary rocks. Along the sides of the valley, large masses of coarse alluvial deposits are left high above the present channel of the stream. Although much placer-work has been done, and some very rich material has been found, the limited extent of the isolated tracts has made placer-mining in this locality generally unprofitable. The valley terminates two miles above Telluride in an amphitheater around which walls rise abruptly several thousand feet. Here the company's mill is situated, being reached by a Bleichert tramway from the mines and also by a spur of the Rio Grande railway from Telluride. At this point, not only are the reddish sandstone and conglomerate beds exposed, but the contact between the conglomerate and the overlying gray volcanic breccia is plainly in view, even at a distance of many miles. A marked stratification is noticeable, indicating the successive layers of igneous breccia, locally termed trachyte. Throughout the entire region this is the favorite name among the miners for the rocks composing the igneous cap of the San Juan

Jan 1, 1897

By Tuncel M. Yegulalp, Peter G. Zambas

In planning an underground room-and-pillar mine, the selection of the shaft or portal location and the orientation of the main haulage arteries is of paramount importance, particularly in view of the high dependence of the cost of truck haulage on the proper definition of these parameters. In an effort to facilitate this selection a computer program was written which, by relating the truck characteristics to the areal configuration of the property or ore body, derives the volume-weighted total fuel and time requirements for hauling ore from every panel within the property to a specified portal or shaft location through a predetermined gridwork of haulage drifts. By varying the size and orientation of the gridwork and the location of the portal or shaft access, an infinite number of configurations can be investigated. The results of this analysis can be plotted to indicate the optimum conditions.

Jan 1, 1974

By Ellis Clark

The greater portion of the brown ore in the vicinity of Easton, along the north slope of the Lehigh Mountain or Durham range of hills, is obtained from mines instead of from open cuts or quarries, as is the case in the ore-beds in the western part of Northampton County, in Lehigh County, and in Berks County. The reasons for this method of procedure are various, and the principal causes of the shaft and regular mine system of working being adopted instead of the open air cuts, are: First, the large amount of stripping that would be necessary, as the richer and more valuable portions of the ore do not appear to be found as near the surface as those in other portions of the Kittatinny valley; second, the occurrence of the ore in regular beds, interstratified with the clay, and, to a less extent, in pockets or erratic deposits, as is the case in the mines of Lehigh County; and third, on account of many of the mines being situated at the immediate base of the Lehigh Mountain, where the surface water would be in such large quantities as to be with difficulty handled, and where the subsequent caving in of the sides of the open cut would be almost certain to expose the gneiss rock, which is water-bearing, the large quantities of water coming from which would probably drown out the ore-bed. Shafts, and a regular system of gangways and mining are therefore required by the configuration of the surface, the depth of the deposits and their geological structure. The ordinary size of the shafts is about four feet square, but where an extensive plant of pumping machinery is required the size may be increased to eight feet by six, with two compartments for the hoisting and pump-shaft respectively. A man-way, consisting of ladders with rests at intervals of twenty or thirty feet, is comprised in the pump-shaft, the wire rope being used for purposes of ascent and descent only in exceptional cases, on account of accidents which

Jan 1, 1879

By Albert D. Pernichele, Wayne C. Smith

Both water pollution and proposed solid waste disposal regulations have a definite effect on the copper leaching industry and some of the major factors affecting the industry are discussed in this paper. New developments of the NPDES are discussed with emphasis on the ‘toxic’ or priority pollutants, and EPA’s philosophy on the control of these pollutants. The protection of groundwater is the prime aim of RCRA through solid/hazardous waste management. Some of the major elements of the RCRA regulations that will effect the copper leaching industry are discussed.

Jan 1, 1980

By R. T. Bayliss

Although every mill-man of even limited experience in the amalgamation of gold-ores is probably aware that copper plates will in time become coated by the accumulation of gold-amalgam, it may be that many do not know to what extent this accumulation occurs in the treatment of ores dissimilar to those with which they are familiar, and under conditions foreign to those with which they have to contend in any given locality. The writer, therefore, feels relieved from the necessity of offering an apology for dealing with such an elementary subject, believing that certain facts in reference thereto, which have recently come under his personal observation, will be interesting to many, and possibly instructive to some persons engaged in the amalgamation of gold-ores. The facts hereinafter stated were observed in the 50-stamp "combination"-mill, owned by the Montana Mining Company, Limited, of England, operating the Drum Lummon mine, situated at Marysville, Montana. The material treated in this mill consists of quartz and ores of somewhat variable character, containing gold and silver in native form, as well as in chemical union with the sulphides of iron and copper. There is also present a little lead, some arsenic and antimony, and a little zinc. The last fair minerals, however, are of irregular occurrence, and but sparingly distributed throughout the ore, and yield only a trace in the analysis of the average material in this mill. The free gold, which is in a condition of fine division, and rarely visible to the naked eye, carries silver as an alloy; and the native silver, which is only occasionally observed, is present in the richer ores in wireand in leaf-form. Of the two precious metals, the ore worked during the past three years and ten months, the period under review, contained about 1/2-ounce of gold, and from 7 to 12 ounces of silver, per ton of 2000 pounds.

Jan 1, 1897

By V. S. Rood, J. A. Norden

The general system of workings at the Utah-Apex is similar to that found in many of the western metalliferous mines. There is a vertical three-compartment shaft extcnding to the surface, from which the various levels have been driven to the orebodies. The 1000-ft. (305-m.) level, about 3/4 mile long, was driven as a haulage and drain adit. Geology The formation is a flat north-dipping series of alternating limestone and quartzite beds. Extensive north-south faulting and fissuring have taken place, resulting in the formation of large replacement orebodies in the crushed zones in the limestone. The orebodies are irregular in shape and size, but follow closely the trend of the mineralizing fissures. The ore consists of galena, pyrite, sphalerite and small values in silver and gold. Large masses of non-commercial pyrite are frequently found in or adjacent to the orebodies, and more or less pyrite is found for some distance in the walls of the orebodies. Lenticular bodies of a black pyritic shale also occur in the zones where extensive faulting has taken place. Mining Methods and Condition of Workings Geological conditions, mentioned before, have made the ground extremely heavy. In mining above the 1000-ft. level, square-set and filling methods were used, but not altogether successfully. The crushing of timbers extended even into the filled portions of the stopes. The filling material itself, consisting of limestone, shale, and pyrite, possessed swelling qualities which added to the difficulty of maintaining

Jan 1, 1920

By S. W. Parr, A. R. Powell

FOUR general methods have been used in the study of the decomposition of coal. The first has been directed toward the processes of coal formation, the second has been by means of microscopic studies, the third from the data of destructive distillation, and the fourth has made use of various solvents. Applying these methods to the sulfur of coal, it has been found that the organic sulfur of plant and animal life enters into the formation of coal and remains in organic combination in the final product. The inorganic sulfur is almost entirely combined as iron pyrites and marcasite. The infiltration of hydrogen-sulfide waters is doubtless a large factor in these combinations. Sulfates are found in very small quantities except where free oxygen has entered the coal strata. The mechanical mixing of detritus with the early coal material is another source of sulfur. In this case the sulfur is distributed in microscopic particles throughout the mass. In destructive distillation, a part of the sulfur comes off as hydrogen sulfide and various thiophen compounds, but this furnishes little information as to the nature of the sulfur compounds in the coal itself. The use of solvents has given valuable data concerning the sulfur compounds in coal. Fremyl and later E. Guignet2 noted the action of alkaline solutions on coal after treatment with nitric acid and Anderson and Roberts3 showed the presence of large quantities of organic sulfur in the extract so obtained. In a study of the phenol extract of coal, Parr and Hadley4 found organic sulfur in the soluble organic material. These investigations proved the presence of organic sulfur in coal in addition to the inorganic forms, such as iron pyrites and sulfates. T. M. Drown6 attempted the analysis of the pyritic and sulfate sulfur as distinct from the organic forms by means of sodium hypobromite; no definite proof of

Jan 1, 1920

Edgar Hall, Tenterfield, New South Wales (communication to the Secretary): Mr. Klepetko* asks for information showing at what percentage antimony and arsenic, as impurities, begin to affect injuriously the quality of brass.

Jan 1, 1899

By A. T. Yu

As the first year of full-scale shiploading operations nears completion, Chile's twin ports of Chafiaral and Caldera have proved instrumental in promoting the growth of that nation's iron ore industry. Located on the Iron Coast several hundred miles below Antofagasta, the two ports boast of new conveyor shiploading facilities uniquely adapted to their coastal environment. Until recently, iron ore producers in this region of Chile have been hampered by antiquated methods of loading crushed ore on ships for transportation to foreign buyers. Use of the "truck-to-lighter- to-ship" method, which dominated heretofore, was too slow and costly to permit expansion of productive mines and exploitation of new high-grade discoveries to meet the growing world demand for such ore.

Jan 8, 1960

By W. J. Kennedy, J. D. Gardner

A systematic method is presented for analyzing and improving energy costs in surface mines. Each mine is divided into drilling and blasting, overburden haulage, ore haulage, crushing and grinding, and lighting system. Specific methods of improving the energy costs of each system are discussed. Contributions of simulation and queueing to energy cost reduction are also discussed.

Jan 1, 1985