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By P. W. Jeran, C. M. McCulloch, Maurice Deul

The natural vertical fracture sys tem in bituminous coalbeds is called cleat. Cleat orientation commonly controls the direction of mining with major development paralleling the face cleat. Previous researchers have categorized the origin of cleat as endogenetic, relating the origin of cleat to compaction and coalification, and exogenetic, relating the origin of cleat to tectonic forces. In the coalbeds studied for this report it was found that tectonic forces were the controlling factor of cleat formation. Face cleats were formed as extension fractures during structural deformation, and butt cleats, as release fractures during erosion and uplift. The face cleat of the Pittsburgh coalbed rotates from N 80° W in north- western West Virginia to N 57° W in southwestern Pennsylvania ; the face cleat maintains a perpendicular orientation to the shifting axial trend of local structures . Cleat orientation in other bituminous coalbeds in Virginia, Utah, Oklahoma, and Central Pennsylvania showed a similar relationship to local structure. Directional permeability of coal is directly related to cleat. Holes drilled perpendicular to the face cleat yield from 2.5 to 10 times the amount of gas released as compared with holes drilled perpendicular to the butt cleat.

Jan 1, 1974

By Kenneth H. Johnston

Information on oil and water production, volume of water injected, core analyses, and well completion data was collected on 28 Red Fork sand water-flood projects for comparison and evaluation of results. An average water injection efficiency of 35 percent, an average water-injected to oil-produced ratio of 16.8:1, and an average loss outside the flood pattern of approximately 45 percent of the injected fluid resulted in an oil recovery to January 1, 1969, of only 5.6 percent of the pore volume, or 9.1 percent of the initial stock-tank oil in place. The principal causes of poor oil recovery from these projects are the losses of large quantities of injection water from the flood patterns through oriented, natural fracture systems or zones of high permeability and excessive channeling of injection fluids from input wells to oil wells. For more efficient operation and a higher percentage of oil recovery from the Red Fork sand and other low-permeability-sand waterflood projects, directional orientation of both induced-and natural-fracture systems should be determined during early development. The success of a low-permeability-sand waterflood project depends to a large extent upon the orientation of the injection wells with the fracture system.

Jan 1, 1970

By L. B. Berger, W. P. Yant, George W. Jones

Improper combustion of natural gas is the cause of low efficiency in heating appliances , also the liberation of carbon monoxide , an insidious and deadly gas . Carbon monoxide is produced during the incomplete combustion of any carbonaceous material , and quantities as low as 0.2 per cent may product death in a very short time . For healthy atmospheric conditions in the home , in which the occupants are continuously exposed , carbon monoxide should not be present in amount greater than 0.01 per cent , which value is taken as the safety limit in this report . The tests herein reported give the conditions which produce carbon monoxide when radiant -fire heaters burning natural gas are used . The conclusions drawn are based on tests made on one type of radiant heater only , but the general conclusions should apply to other types of radiant heaters of similar construction . The gas consumption , gas pressure , orifice pressure , size of orifice , and heater adjustments were changed so as to obtain as many different operating conditions as possible . In a general way the tests were carried out under the same conditions that the heater might be operated in the home .

Feb 1, 1923

By B. T. Brady

Results of a study are presented of the effect of low radial reinforcement pressure on the postfailure characteristics of two types of granite, a sandstone, and marble. The low radial reinforcement pressure is applied to the rock surface by a gooch rubber sleeve. The gooch rubber sleeve provides a radial pressure of less than 1 psi pressure to the rock surface. This method of support gives an average strength increase of approximately 8 percent to the fractured rock sample.

Jan 1, 1973

By A. B. Hooler

"A complete list of permissible mine equipment, tested and approved by the Bureau of Mines previous to January 1, 1947, was published as Information Circular 7432. 3/The present list is a supplement thereto that includes all of the equipment approved during the calendar year 1947.The items are numbered to indicate the consecutive order in which each type of machine or device was approved in its particular classification. Thus, Information Circular 7432 showed six air compressors on the active list; two additional compressors, Nos. 7 and 8 in this category, were approved during 1947.Items 2 and 7, unmounted loader and power unit, respectively, under Loading and Conveying Equipment, item 2, rubber-mounted mining machine and item 8, distribution box, appear in Information Circular 7432. They are repeated to show that approvals of these four equipments were extended to cover an additional voltage rating which requires material change in design.Equipment listed in these circulars is approved by the Bureau of Mines only when found upon inspection and test to comply with minimum standards of safety as outlined in schedules prepared on the basis of many years of experience in dealing with safety problems of the coal-mining industry. The use of such equipment in mines known to be gassy, as well as in those that may become so, is earnestly recommended in the interests of safety. This circular is published so that the industry may be kept informed as to the many types of machines, devices, and lamps that are available for reducing explosion and other hazards incidental to coal mining. The present paper, with Information Circular 7432, gives the complete list of permissible mine equipment that is available under the various classifications."

May 1, 1948

By D. B. Starkey

Investigation into the expressions of the field produced by a loop over a conducting half space or in an infinite conducting half space are well documented. Reasonably complex descriptions of the effects of stratification also are reported. However, a model which must contain all of these complexities because of transmission to depths of 15,000 feet and also include the pertibation of the field by a verticle cylindrical steel casing loses its facility in the field or for quick, accurate approximation to field magnitudes and phase. This paper describes the results of two field tests to determine the attenuation and phase versus depth and frequency of an electromagnetic wave (induction field). A simple two-layer model is postulated to predict the magnitude and phase of the induced field which does not require sophisticated computing tools. Correlation of the model with experimental results show agreement of most amplitude measurements to within 3 db and most phase measurements to within five degrees. The tests were conducted in a 7400 foot deep well in Nevada and an 11,000 foot deep well in Wyoming which had conductivities ranging from .0025 mhos/m to .25 mhos/m. The surface transmitting dipole had an area of ~ 10 6 feet squared and constant frequency signals of 1.5 Hz to 20 Hz were transmitted through the earth utilizing less than 65 watts of power. Model Description The magnetic field intensity components generated by a magnetic dipole immersed in an infinite homogeneous medium can be expressed in spherical coordinates as: [ ] where N, I, and (p a ) are the transmitting antenna turns, current, and effective area, respectively, and r is the range from the loops circumference to the measurement point. The case of interest for these experiments, however, is the special case of coaxial dipoles, i.e., ? = 180° . For this case H?= 0 and H reduces to: [ ]

Jan 1, 1973

By G. R. Hopkins

"A new record in fuel efficiency at petroleum refineries was achieved in 1935, when an average of only 615,000 B. t. u. was needed to refine a barrel of crude oil, compared with an average of 638,000 B. t. u. in 1934 and 829,000 B. t. u. In 1925. (See fig. 1.)Refiners have made almost uninterrupted progress in firing efficiency during the last decade although much of this gain was brought about by improved technique and greater use of heat exchangers and pipe stills, the determining factor was the trend in crude runs to stills. Most plants can increase their crude throughput materially with but small increase in fuel consumption. Consequently, in years in which crude runs have increased substantially, average requirements have declined; but in years in which crude runs have decreased, the average has tended upward. This conclusion is confirmed by figure 1, which shows that there has been but one minor exception to this rule in the last 10 years.Technical progress in fuel efficiency may be illustrated by comparing crude runs and total B. t, u. consumed. Between 1925 and 1935 crude runs to stills increased 31 percent, but the total quantity of heat required did not increase; in fact, it declined slightly.The trend of modern still construction is from shell stills, in which a large body of oil is heated, to tube stills, in which the heat comes into much closer contact with the oil. In 1935 the total capacity of operating pipe stills increased about 4 percent; this increase, though small, probably was related to the gain in average efficiency.The Increased use of heat exchangers and their role as fuel savers have been discussed in previous reports of this series. It is sufficient to say that refiners with insufficient exchange capacity added as much in 1935 as their budgets would permit."

Jan 1, 1937

By C. M. Frost

The hydrodesulfurization characteristics of a Venezuelan topped crude oil and a Venezuelan reduced crude oil were determined at temperatures from 740° to 850° F, pressures from 800 to 1,600 psig, and space velocities from 1.0 to 2.0 Vo/Vc/hr. Kinetic calculations showed that under these conditions the desulfurization reaction was first order with respect to sulfur and had an average activation energy of 32.5 kcal/mo1. Catalyst life tests made at 750° F, with pressures of 800, 1,200, and 1,600 psig and space velocities of 1.0 and 1.25 Vo/Ve/hr, showed that the decrease in the relative activity of the catalyst was a logarithmic function of time or volume of oil processed and the amount of vanadium deposited on the catalyst. Comparative tests made with residual fuels prepared from a Wilmington, Calif., crude oil and a Wyoming asphaltic crude oil showed that catalyst life may be extended by processing fuel oil with a low metal content, but it may be shortened by the presence of large amounts of asphalt in the feed.

Jan 1, 1971

By L. W. Brandt

Studies of liquid-vapor equilibria of gas mixtures at the Bureau of Mines Amarillo Helium Plant Laboratory require that the equilibrium cell be maintained uniformly at any desired temperature from approximately room temperature to -320° F. The temperature-control system must also tolerate a substantial heat input, in the form of warm gas flowing into the cell, without loss of control. Temperatures between the sublimation temperature of carbon dioxide (-109° F.) and the boiling point of liquid nitrogen (320° F.) are usually obtained by methods utilizing a hydrocarbon liquid bath cooled by liquid nitrogen.4/5/6/7/ Owing to the fire hazard attending such baths, a safer method of temperature control was desirable.

Jan 1, 1955

By C. Q. Cupps

Rate of gas diffusion in reservoir oil has been investigated in an effort to explain the variation in oil characteristics observed in the Weber Sandstone reservoir, Rangely field, Colorado. Coefficients of gas diffusion were determined experimentally for the Rangely oil system and used in a mathematical simulation of gas diffusion during the probable life of the Rangely reservoir, estimated at 65 million years. The simulator involved solution of Fick's law for diffusion in two dimensions by the method of finite difference and successive over-relaxation. The results show that continuing gas diffusion is a logical explanation for the variation in oil characteristics at Rangely and that the pattern of gas distribution by diffusion in an asymmetrical reservoir will not conform to structural contours as originally proposed.

Jan 1, 1971

By Wesley A. Grosh

The Allah Cooper mine, in Louisa County, Va., formerly was a producer of lead and zinc. It was believed that the critical shortage of leach and zinc and the fact that some ore had been produced at this mine justified exploration of it. A preliminary examination was made on April 30, 1943, by J. E. Hill, a Bureau of Mines Engineer. Diamond drilling was done on the property from November 30 to December 18, 1943, to determine whether the sulfide body extended to depth. One hole drilled to a depth of 650 feet and located so as to cut the Allah Cooper ore shoot about 150 feet below the lowest known mine workings failed to disclose sulfide vein at that depth.

Jan 1, 1949

By G. S. Rice, R. V. Wheeler

"In September 1923, a proposal was made through official diplomatic channels by the British Safety in Mines Research Board to the United States Bureau of Mines for ""closer cooperation between the two countries in investigations into the causes and means of prevention of mining dangers."" This proposal was cordially accepted by the Bureau of Mines and was officially approved.In the spring of 1924 cooperation was .formally begun. It contemplated, as stated officially, ""full exchanges of information, a joint program of research, and periodic exchange of personnel so as to assure concordant results. By making the resources of both organizations available it will hasten the attainment of results, will secure better: checks for, accuracy, and in the end will save money for both by avoiding duplication and repetition.""This joint work has been carried-on successfully since that time and has developed valuable results, reports on which have been issued from time to time. The progress report which follows gives the results of the studies and work carried on in 1929.During 1929 all the phases of our cooperative research, begun in previous years, have developed normally. The exchange of formal monthly reports on all programs of mutual interest has been continued and has proved an invaluable, means of maintaining contact between the investigators of both organizations. There has been no diminution in the exchange of routine progress reports on specific subjects or in direct correspondence. The interchange of personnel has been maintained, and we can say that the mutual benefits to be derived from this form of cooperation are so great as to be difficult to overestimate. It leads to an appreciation of methods of research and modes of thought in the interpretation of results obtainable in no other way, and engenders a frankness and intimacy which must continuously enhance the value of future cooperation.Dr. S. R. Katz, who was assigned for service with the Safety in Mines Research Board in April, 1928, returned to America in May, 1929. During his stay in England he completed, in cooperation with members of the board's staff, the equipment of a gas-mask laboratory and designed and tested a new form of gas-mask canister. A publication of the Safety in Mines Research Board dealing with this investigation has been prepared and approved and will .be .issued in the near future. In additions Dr. Katz imparted to those with whom he was associated much of his knowledge and technique regarding his particular subjects. He delivered two lectures to the board's staff, the subjects be ""Gas Masks"" and ""The Intensity of Odors"", and gave papers before the Midland Institute of 'lining Engineers and the Birmingham University Mining Society on the subject of ""Industrial Gas Masks""."

Jun 1, 1930

By J. G. Walters

In a survey of the coking properties of United States coals, the Bureau of Mines has accumulated data on more than 500 coals and blends tested by the Bureau of Mines-American Gas Association (BM-AGA) method.4/ The importance of these tests depends upon the fact that a greater number of different coals has been tested in this apparatus than in any other of similar scale, thus permitting comparison of the carbonizing properties of many coals. Evaluation of BM-AGA results with respect to industrial data supplied by member firms of the American Gas Association was one of the first objectives in developing this test apparatus and procedure. Early data showed that, de-pendent upon BM-AGA carbonizing temperature, BM-AGA and commercial results agree closely.5/ Because of limited data, statistical relationships were not established at that time.

Jan 1, 1959

By Rose L. Ballard

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Included also are the tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of volume I and in the State chapters of volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in this chapter is what is ordinarily termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1982

By I. A. Jacobson

In a closely controlled laboratory retorting system for oil shale, a relationship was developed by the Bureau of Mines between the temperature in the retort and the weight ratio of ethylene to ethane in the gases produced. Reciprocal temperature was shown to be directly proportional to the log ([ethylene]/[ethane]). From this relationship a number, called retorting index, was developed. The retorting index has the dimension of temperature, but its magnitude depends on both temperature and residence time for the reactants in the heated zone in the oil-shale retort. The slopes of the lines relating reciprocal temperature and the logarithm of the ethylene-ethane ratios are nearly constant for each of the retorting processes for which data have been presented. The retorting index should be a valuable tool to control the operation of oil-shale retorts, either aboveground or in situ. If an optimum operating condition can be established, the maintenance of the optimum or the departure from it should be easily monitored by use of the index.

Jan 1, 1974

By R. L. Grant, R. W. Van Dolah, N. E. Hanna

An experimental investigation was conducted to assay the relation between natural gas concentration and ignitibility of the gallery atmosphere . Both the gas concentration representing maximum ignitibility and the relationship between certain properties of the explosives and their incendivity are discussed . The data show that variation in the natural gas content in the gallery can have a highly significant effect on ignitibility of the gallery atmosphere ; maximum ignitibility of the atmosphere by permissible explosives occurs with approximately 8.1 percent natural gas . The study also shows that incendivity of a permissible explosive cannot be determined only by its detonation velocity , oxygen balance , or ballistic mortar strength . However , for similar type explosives , trends observed indicate that their incendivity increases with detonation velocity or bulk strength . Additionally , for underoxidized explosives studied here , the more negative the oxygen balance the less incendive was the explosive within a class defined by salt content .

Jan 1, 1963

By John C. Franklin

The Bureau of Mines conducted extensive laboratory and limited field tests to determine whether a polymeric material could effectively reduce the emanation rate of radon gas from uranium ore. In the laboratory 46 different single-coat materials and 14 two-coat applications were tested. The laboratory tests showed that up to 100 percent of the radon gas could be sealed into the rock. Materials tested in the laboratory were polyesters, furan resins, epoxies, latices, and totally inorganic coatings. From the laboratory work six different materials were selected for field testing. The first test was single-coat materials in five static chambers; the second test used two-coat applications in an open chamber. Both tests were conducted in the Dakota mine at Grants, N. Mex. During the second test, the amanation rate of radon gas was reduced up to 62 percent.

Jan 1, 1975

The Bahamas Oil Refining Co. (BORCO) refinery in Freeport continued to operate at less than half its full 500,000-barrel-per-day capacity. Although owned through subsidiaries by the Carey Energy Corp (65%) and Standard Oil Co. of California (35%), BORCO is ineligible for participation in the Crude Oil Entitlements Program granted to companies operating within the United States proper or its territories. Like some other Caribbean refineries, BORCO has suffered a loss of normal market outlet due to the wt advantage afforded U.S. refineries by the Entitlements Program. Saudi Arabia, Nigeria, and Libya are the major suppliers of crude for the refinery. Its principal products, motor spirits, aviation fuel, distillate fuels, and residual fuel oils, were marketed in the United States and Puerto Rim. The Government-owned Bahamas Development Corp. and Burmah Oil Co. Ltd., held discussions pertaining to a renegotiation of Burmah Oil's management contract for the Grand Bahama Oil Transshipment terminal. The desired contract modifications were not made public but financial problems have plagued the terminal and its operation since construction started in 1972.

Jan 1, 1981

By J. W. Thompson

"The ordinance of March 27, 1919, contains provisions relative to the exploration for, Ind the exploitations of bauxite in the Colony of Surinam in Dutch Guiana.Permission to explore is limited to: Netherlanders; inhabitants of the Netherlands; inhabitants of Surinam; companies established in Netherlands, and companies established in Surinam.Holders of concessions for the exploitation of bauxite are limited to companies established in the Netherlands, or in Surinam, and these must reside in the Colony or must be represented the constantly.A permission or concession lapses: (a) when the holder ceases to have the required qualifications; (b) on the death of the holder where the assigns fail within one year to prove the required qualifications.Any dispute concerning the required qualifications must be decided by the Judge in the manner to be regulated by colonial ordinance.The Governor may, after consultation with the Privy-Council reserve tracts of land for the exploration and exploitation of Bauxite, either for the Government directly, or for concession under special provisions. These provisions shall be fixed by virtue of the colonial ordinances.Application for permission to explore shall be made in accordance with existing laws. Simultaneous applications, those made on the same day, must be decided by drawing lots; but an application for the concession for exploitation has preference ovor that for permission for exploration. On notice of objection to the drawing of lots, the Governor may in his discretion, declare the drawing null and void and order a re-drawing."

May 1, 1920

By James P. Ulery, Stephen J. Kravits, William P. Diamond

This report presents results of a cooperative research project between the U.S. Bureau of Mines and Beth Energy Mines, Inc. Four coreholes (two before mining and two after mining) were drilled at a longwall mine operating in the Lower Kittanning Coalbed to obtain coal and rock samples from overlying strata to determine their gas content at various times in the mining cycle. The results of those tests indicate that 91 pct of the gas removed from the overlying strata came from coalbeds. Material balance calculations were made to compare the volume of gas produced both from gob gas vent holes drilled on the panel and gas removed by the mine's ventilation system with the volume of gas removed from strata directly overlying the panel to a height of 275 ft. This analysis indicates that only 40 pct of the total gas produced from the panel actually came from the strata directly overlying the panel. The remaining volume of gas production probably migrated to the Iongwall gob from overlying, and perhaps underlying, strata immediately adjacent to the panel and perhaps from greater distances downdip because of the establishment of a long-term pressure gradient in the study area.

Jan 1, 1992