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WE the undersigned, being all persons of full age and citizens of the United States, and a majority residents of the State of New York, desiring to form a corporation pursuant to the provisions of the Membership Corporations Law for the purpose of incorporating, as provided in Section 5 of Article I. of said law, the existing unincorporated association known as American Institute of Mining Engineers, do hereby make, acknowledge and file this Certificate for that purpose, and do Certify as follows I. That the American Institute of Mining Engineers is an unincorporated association organized and existing with the object of promoting the arts and sciences connected with the economic production of the useful minerals and metals and the welfare of those employed in these industries by means of meetings for social intercourse and the reading and discussion of professional papers, and to circulate by means of publications among its members and associates the information thus obtained.

Jan 1, 1917

WE the undersigned, being all persons of full age and citizens of the United States, and a majority residents of the State of New York, desiring to form a corporation pursuant to the provisions of the Membership Corporations Law for the purpose of incorporating, as provided in Section 5 of Article I. of said law, the existing unincorporated association known as American Institute of Mining Engineers, do hereby make, acknowledge and file this Certificate for that purpose, and do Certify as follows I. That the American Institute of Mining Engineers is an unincorporated association organized and existing with the object of promoting the arts and sciences connected with the economic production of the useful minerals and metals and the welfare of those employed in these industries by means of meetings for social intercourse and the reading and discussion of professional papers, and to circulate by means of publications among its members and associates the information thus obtained.

Jan 1, 1923

WE, the undersigned, being all persons of full age and citizens of the United States and a majority residents of the State of New York, desiring to form a corporation pursuant to the provisions of the Membership Corporations Law for the purpose of incorporating, as provided in Section 5 of Article I. of said law, the existing unincorporated association known as American Institute of Mining and Metallurgical Engineers, Incorporated, do hereby make, acknowledge and file this Certificate for that purpose, and do certify as follows: I. That the American Institute of Mining Engineers is an unincorporated association organized and existing with the object of promoting the arts and sciences connected with the economic production of the useful minerals and metals and the welfare of those employed in these industries by means of meetings for social intercourse and the reading and discussion of professional papers, and to circulate by means of publications among its members and associates the information thus obtained.

Jan 1, 1946

By M. R. Tek, R. L. Nielsen

The scaling laws as formulated by Rapoport relate dynamically similar flow systems in porous media each involving two immiscible, incompressible fluids. A two-dimensional numerical technique for solving the differential equations describing systems of this type has been employed to assess the practical value of the scaling laws in light of the virtually unscalable nature of relative permeability and capillary pressure curves and boundary conditions. Two hypothetical systems — a gas reservoir subject to water drive and the laboratory scaled model of that reservoir — were investigated with emphasis placed on water coning near a production well. Comparison of the computed behavior of these par ticular systems shows that water coning in the reservoir would be more severe than one would expect from an experimental study of a laboratory model scaled within practical limits to the reservoir system. This paper also presents modifications of the scaling laws which are available for systems that can be described adequately in two-dimensional Cartesian coordinates. INTRODUCTION Present day digital computing equipment and methods of numerical analysis allow realistic and quantitative studies to be carried out for many two-phase flow systems in porous media. Before these tools became available the anticipated behavior of systems of this type could be inferred only from analytical solutions of simplified mathematical models or from experimental studies performed on laboratory models. To reproduce the behavior of a reservoir system on the laboratory scale, certain relationships must be satisfied between physical and geometric properties of the reservoir and laboratory systems. Where the reservoir fluids may be considered as two immiscible and incompressible phases, the necessary relationships have been formulated by Rapoportl and others.2-5 Rapoport's scaling laws follow from inspectional analysis of the differential equation describing phase saturation distribution in such systems. It will be recalled that these scaling laws presuppose three conditions: (1) the relative permeability curves must be identical for the model and prototype; (2) the capillary pressure curve (function of phase saturation) for the model must be linearly related to that of the prototype; and (3) boundary conditions imposed on the model must duplicate those existing at the boundaries of the prototype. These three requirements seldom if ever can be satisfied in scaling an actual reservoir to the laboratory system because: (1) The laboratory medium normally will be unconsolidated (glass beads or sand) while the reservoir usually is consolidated. Relative permeability and capillary pressure curves are usually quite different for consolidated and unconsolidated porous media. (2) The reservoir usually will be surrounded by a large aquifer which could be simulated in the laboratory only to a limited extent. (3) Wells present in the reservoir would scale to microscopic dimensions in the laboratory if geometric similarity is to be maintained. In view of these considerations, rigorous scaling of even a totally defined reservoir probably would never be possible. The purpose of this paper is to assess the practical value of the scaling laws in the light of the unscalable variables. This has been done by carrying out numerical solutions in two dimensions to the differential equations describing the flow of two immiscible, incompressible fluids in porous media for a field scale reservoir and a laboratory model of that reservoir. While both the reservoir and the laboratory model were purely fictional, each has been made as realistic and representative as possible. The field problem selected as the basis for the investigation was an inhomogeneous, layered gas reservoir initially at capillary gravitational equilibrium and subsequently produced in the presence of water drive. The laboratory model of this reservoir was designed to utilize oil and water in a glass bead pack. The numerical treatment employed was similar to that of Douglas, Peaceman and Rachford6 and it included both capillary and gravitational forces as

SEC. 1. This Institute is incorporated under the Membership Corporations law of the State of New York; its corporate name is American Institute of Mining and Metallurgical Engineers, Inc.; and its abbreviated title A. I. M. E. SEC. 2. The objects of this Institute, as set forth in its certificate of incorporation, are: "To promote the arts and sciences connected with the economic production of the useful minerals and metals, and the welfare of those employed in these industries by all lawful means; to hold meetings for social intercourse and the reading and discussion of professional papers, and to circulate by means of publications among its members the information the obtained, and to establish and maintain a place for meeting of its members, and a hall for the reading of papers and delivery of address, and a library of books relating to subjects cognate to the sciences and arts of mining and metallurgy."

Jan 1, 1942

WE the undersigned, being all persons of full age and citizens of the United States, and a majority residents of the State of New York, desiring to form a corporation pursuant to the provisions of the Membership Corporations Law for the purpose of incorporating, as provided in Section 5 of Article I. of said law, the existing unincorporated association known as American Institute of Mining Engineers, do hereby make, acknowledge and file this Certificate for that purpose, and do Certify as follows I. That the American Institute of Mining Engineers is an unincorporated association organized and existing with the object of promoting the arts and sciences connected with the economic production of the useful minerals and metals and the welfare of those employed in these industries by means of meetings for social intercourse and the reading and discussion of professional papers, and to circulate by means of publications among its members and associates the information thus obtained.

Jan 1, 1923

F. McMillan Stanton was born in New York City on May 23, 1865, the son of an English father and of a mother whose family was linked with that of Peter Stuyvesant. Mr. Stanton took his degree from the School of Mines of Columbia University in 1887, worked for two years as an assayer and surveyor and then went into the mining field on his own account. After a few years, he was offered a position with the Atlantic Mining Co., and began the work which was to continue with marked success for twenty-three years. In 1910, Mr. Stanton retired and went to Europe for a rest. Upon his return in 1914, he was elected treasurer and director of the Mohawk Mining Co., the Wolverine Copper Mining Co. and the Michigan Copper Mining Co., to which group was later added the White Pine Extension, Copper Co., and continued to serve these companies until the time of his death, Sept. 12, 1916.

Jan 12, 1916

SEC. 1. This Institute is incorporated under the Membership Corporations law of the State of New York; its corporate name is American Institute of Mining and Metallurgical Engineers, Inc.; and its abbreviated title A. I. M. E. SEC. 2. The objects of this Institute, as set forth in its certificate of incorporation, are: "To promote the arts and sciences connected with the economic production of the useful minerals and metals, and the welfare of those employed in these industries by all lawful means; to hold meetings for social intercourse and the reading and discussion of professional papers, and to circulate by means of publications among its members the information thus obtained, and to establish and maintain a place for meeting of its members, and a hall for the reading of papers and delivery of addresses, and a library of books relating to subjects cognate to the sciences and arts of mining and metallurgy."

Jan 1, 1932

By Ferron A. Olson

Occasionally it is good to consider the past, assess the present and project the future. Curriculum, enrollment, matriculation of graduates and changes in industry which influence mineral education are all relevant for determining what changes will be needed in educational institutions to support growth and development in the United States. It would appear likely that with environmental pressures, energy needs with present stress in fossil fuels and general societal needs for metals and minerals that mining and metallurgical engineering faces a period of growth and may be on the threshold of a new era with a vitality that has not been enjoyed for several decades. The following information is based on material obtained through questionnaires received from twelve schools accredited in mining or mineral engineering (out of 18 in the U.S.), 2 not accredited and 5 which no longer have mineral engineering disciplines. The schools presented do not include the smaller nor larges of the undergraduate programs in mining engineering.

Jan 8, 1972

By H. F. Mills

The Iron King mine is I2 miles east of Prescott Arizona, in low foothills of the Agua Fria mining district. It was operated in 1906 and 1907, using gravity methods of concentration, mostly on oxide ores. In 1923 and 1924 shipments of sulphide ores were made to the Humboldt smelter. It remained inactive and stripped unti1 1936, when it was unwatered and sampled to the 400-ft level, the bottom at that time. In 1937 the Iron King Mining Co. purchased the mine and shipped oxide ores. During 1938 a bulk flotation plant of I40 tons daily capacity was erected. The mill has been enlarged and operations have been continuous since the mill first started. In July 1942, the Shattuck Denn Mining Corporation purchased the physical assets from the Iron King Mining Co., and since that time it has operated as the Iron King Branch of the Shattuck Dcnn Mining Corporation. Economic metals recovered are gold, zinc, silver, lead, a little copper, and fluxing pyrite. The ore occurs as a series of northward-dipping shoots arranged in echelon pattern, the series extending over a length of 3500 ft. Strike lengths of shoots vary from 60 to 600 ft, and widths from 3 ft to as much as 14 ft. The ore occurs in a sheared zone in pre-Cambrian chloritic schist. This schist belt is about 6 miles wide, and the ore zone is about 4 miles from the pre-Cambrian granites to the west. No intrusive rocks have been found in the mine, nor is there evidence of any on surface that might indicate a genetic connection with the ore occurrence (Fig I). The schists strike N23°E and dip 75° to the northwest, which might indicate an overturned thrusting from the granites. In the upper levels, the echelon pattern in which the ore occurs was quite regular. no disturbance of the enclosing schist, or of any faulting that might contribute to the formation of the ore pattern was noted. There is a possibility that the ore zone may be on the axis of an isoclinal fold. Another interesting feature is the more or less typical zoning of minerals along the strike in each of the ore shoots (Fig 2). The north end of each shoot is enclosed by schist, while the south ends usually extend out at full width beyond the economic mining limits in a pyrite-quartz low-grade material. The plane of demarcation between ore and schist is very sharp, with little or no impregnation of sulphide in the schist, especially on the footwall side. The footwall schists are usually firm and strong, and vary from dioritic phases to fine-grained, lighter colored bands, almost silky in texture. The hanging wall for a width of 50 to 80 ft consists of alternating sheetings of chloritic and pyritic schists. The mine is now partly developed to the 920-ft level, with some diamond drilling from the 1150-ft station of No. 6 shaft. Economically there has been little change in nature or grade of ore from the top of the sulphides, about 200 ft below surface, to the bottom levels. There have been a few echelons in depth, just as there are in plan, and while a few shoots have had

Jan 1, 1949

By H. F. Mills

The Iron King mine is I2 miles east of Prescott Arizona, in low foothills of the Agua Fria mining district. It was operated in 1906 and 1907, using gravity methods of concentration, mostly on oxide ores. In 1923 and 1924 shipments of sulphide ores were made to the Humboldt smelter. It remained inactive and stripped unti1 1936, when it was unwatered and sampled to the 400-ft level, the bottom at that time. In 1937 the Iron King Mining Co. purchased the mine and shipped oxide ores. During 1938 a bulk flotation plant of I40 tons daily capacity was erected. The mill has been enlarged and operations have been continuous since the mill first started. In July 1942, the Shattuck Denn Mining Corporation purchased the physical assets from the Iron King Mining Co., and since that time it has operated as the Iron King Branch of the Shattuck Dcnn Mining Corporation. Economic metals recovered are gold, zinc, silver, lead, a little copper, and fluxing pyrite. The ore occurs as a series of northward-dipping shoots arranged in echelon pattern, the series extending over a length of 3500 ft. Strike lengths of shoots vary from 60 to 600 ft, and widths from 3 ft to as much as 14 ft. The ore occurs in a sheared zone in pre-Cambrian chloritic schist. This schist belt is about 6 miles wide, and the ore zone is about 4 miles from the pre-Cambrian granites to the west. No intrusive rocks have been found in the mine, nor is there evidence of any on surface that might indicate a genetic connection with the ore occurrence (Fig I). The schists strike N23°E and dip 75° to the northwest, which might indicate an overturned thrusting from the granites. In the upper levels, the echelon pattern in which the ore occurs was quite regular. no disturbance of the enclosing schist, or of any faulting that might contribute to the formation of the ore pattern was noted. There is a possibility that the ore zone may be on the axis of an isoclinal fold. Another interesting feature is the more or less typical zoning of minerals along the strike in each of the ore shoots (Fig 2). The north end of each shoot is enclosed by schist, while the south ends usually extend out at full width beyond the economic mining limits in a pyrite-quartz low-grade material. The plane of demarcation between ore and schist is very sharp, with little or no impregnation of sulphide in the schist, especially on the footwall side. The footwall schists are usually firm and strong, and vary from dioritic phases to fine-grained, lighter colored bands, almost silky in texture. The hanging wall for a width of 50 to 80 ft consists of alternating sheetings of chloritic and pyritic schists. The mine is now partly developed to the 920-ft level, with some diamond drilling from the 1150-ft station of No. 6 shaft. Economically there has been little change in nature or grade of ore from the top of the sulphides, about 200 ft below surface, to the bottom levels. There have been a few echelons in depth, just as there are in plan, and while a few shoots have had

Jan 1, 1949

By C. W. Donnelly, Louise B. Freeman, Coleman D. Hunter

It is with pride that the authors of this paper report. that during 1944 the production of petroleum in Kentucky passed its all-time peak, 9,496,985 bbl. being contributed. The delivery of natural gas, especially from eastern Kentucky, was maintained and possibly exceeded the highest deliveries of the past. To raise the production of oil and gas was not easy with inferior and worn-out equipment and the shortage of skilled labor. Reminiscent of the early days of the industry in the state, particularly in the hills of Elliott County, where mud roads often have gradients of 45º, was the replacement of worn-out trucks and tractors by oxen. Of the total 9,496,985 bbl., 17 per cent was contributed by the part of Kentucky that is east of the Cincinnati arch, as compared with the total of 7,010,776 bbl. contributed in 1943, of which 25 per cent was contributed by eastern Kentucky. This discrepancy is due to the discovery of more new fields in western Kentucky rather than to a decrease in production in the eastern fields, where the average has been maintained by reconditioning and secondary recovery of old fields and further development of new pools reported for the first time in 1943. In all, 1103 wells were known to have been drilled in the state during 1944, of which 659 were drilled in western Kentucky and 444 in eastern Kentucky. The exact number of wells drilled for any year is never known, as drilling permits are not required except 'when it is planned to drill through a workable coal seam. Of the total number of wells drilled, 459 were oil wells, 229 gas wells and 415 dry holes. The monthly production was as follows: January........................... 659,496 February.......................... 658,606 March...................... ...... 711,619 April............................. 649,926 May............................... 754,892 June.............................. 730,369 July.............................. 761,762 August............................ 878,053 September...................... 863,150 October........................... 968,732 November........................ 961,999 December........................ . 898,636 Western Kentucky In western Kentucky 352 wells were completed as oil wells with a total initial production of 47,922 bbl. of oil, the average being 136 bbl. per well. Two wells produced gas, the total initial production being 1,594,000 cu, ft. One hundred and eighteon wildcat wells were drilled, of which 107 were dry holes and 11 were oil wells. Three of the latter proved to be the discovery wells of commercial pools. Twelve new pools were discovered during 1944, none of major importance, as indicated in Table 2. The Utley pool, due to a stratigraphic trap on the flank of a closed structure, found oil in the Mcclosky at 2565 ft. in the discovery well, with initial productioil of 1000 bbl. The average daily production is now 227 bbl. from seven wells. The East Poole field, with the discovery well in the Tar Springs sandstone at 1811

Jan 1, 1945

By James A. Barr

The writer's first experience with flotation was during World War I, in the bene-ficiation of Alabama graphite schist ores. One plant used a cone with a peripheral overflow; dried ore was distributed by a rotating disk onto the surface of the water. No reagents were added' The flake-graphite film floated along with some fine silica. Dewatering screens separated the flake. Naturally unit capacities were low but results were satisfactory. Minerals separation mechanical flotation machines were used in another graphite mill. pine oil was added directly to the head cells, with very good results. All the graphite concentrates from both types of flotation were carefully refined after drying by passing through burr mills, followed by very close sizing on sifters. In March 1927, the writer ran a very successful flotation test on minus 28-mesh, deslimed, Tennessee brown phosphate "sand,"† using a mechanical laboratory machine built in the shops of the Anaconda Copper Mining Co., through the courtesy of Ernest Klepetko. The machine was soon converted to a subaeration type, with improved results. This phosphate research program was greatly enlarged and led to the formation of the phosphate Recovery corporation. The development of nonmetallic flotation followed rapidly. The first flotation machine for bene- ficiation of phosphate was installed in January 1928, in a pilot mill, by International Minerals and Chemical Corporation, at Mulberry, Florida. These machines were Minerals Separation, 24-in., sub-,,,tion types, with weir control of pulp between cells. The sand bleeders were very small—about 1¼-in. diameter. As the feed flake. Is to 25 per cent plus 28-mesh material, the cells choked up frequently. This was corrected by cutting a 2 by 6-in. bleeder opening above the impellers, at grid level, which short-circuited the coarse fractions directly into the feed of the next cell. The matter of size classification and grinding was a considerable problem, which does not come within the scope of this article. Because of the troubles noted above, cascade-type roughers were installed in the second flotation plant, built about 1930. Experimental cells had been tried in 1928. General plant layout is shown in Fig. 1 and details of the cascade construction in Fig. 2. The cascade installation in plant NO. 2 gave good results and eliminated troubles due to choke-ups and coarse feed. The capacities and metallurgical results equaled those of the modified 24-in. Minerals Separation flotation machines in plant No. I The objections to the cascade installation are the floor space and mill height required. In 1939 an improved Minerals Separation machine was tested in parallel with the cascades. Extensive tests indicated

Jan 1, 1947

By James A. Barr

The writer's first experience with flotation was during World War I, in the bene-ficiation of Alabama graphite schist ores. One plant used a cone with a peripheral overflow; dried ore was distributed by a rotating disk onto the surface of the water. No reagents were added' The flake-graphite film floated along with some fine silica. Dewatering screens separated the flake. Naturally unit capacities were low but results were satisfactory. Minerals separation mechanical flotation machines were used in another graphite mill. pine oil was added directly to the head cells, with very good results. All the graphite concentrates from both types of flotation were carefully refined after drying by passing through burr mills, followed by very close sizing on sifters. In March 1927, the writer ran a very successful flotation test on minus 28-mesh, deslimed, Tennessee brown phosphate "sand,"† using a mechanical laboratory machine built in the shops of the Anaconda Copper Mining Co., through the courtesy of Ernest Klepetko. The machine was soon converted to a subaeration type, with improved results. This phosphate research program was greatly enlarged and led to the formation of the phosphate Recovery corporation. The development of nonmetallic flotation followed rapidly. The first flotation machine for bene- ficiation of phosphate was installed in January 1928, in a pilot mill, by International Minerals and Chemical Corporation, at Mulberry, Florida. These machines were Minerals Separation, 24-in., sub-,,,tion types, with weir control of pulp between cells. The sand bleeders were very small—about 1¼-in. diameter. As the feed flake. Is to 25 per cent plus 28-mesh material, the cells choked up frequently. This was corrected by cutting a 2 by 6-in. bleeder opening above the impellers, at grid level, which short-circuited the coarse fractions directly into the feed of the next cell. The matter of size classification and grinding was a considerable problem, which does not come within the scope of this article. Because of the troubles noted above, cascade-type roughers were installed in the second flotation plant, built about 1930. Experimental cells had been tried in 1928. General plant layout is shown in Fig. 1 and details of the cascade construction in Fig. 2. The cascade installation in plant NO. 2 gave good results and eliminated troubles due to choke-ups and coarse feed. The capacities and metallurgical results equaled those of the modified 24-in. Minerals Separation flotation machines in plant No. I The objections to the cascade installation are the floor space and mill height required. In 1939 an improved Minerals Separation machine was tested in parallel with the cascades. Extensive tests indicated

Jan 1, 1947

By John T. Galey

An intensified search for gas, because of the shortage in the area, led to the completion of 482 wells in southwestern Pennsylvania during 1944. This number was 27 more than the number in 1943, but 118 of the wells were nonproductive. Shallow Development Oil The initial production of the 25 producers completed was slightly less than was obtained from four wells above last yearJs total. The largest well, 20 bbl., was found in the Big Injun (Miss.) sand in Morris township, Washington County, at a depth of 2085 ft. It is currently producing about 3 bbl. per day. Outside the main producing area, a well drilled in Nicholson township, Fayette County, obtained 15 bbl. per day from 1864 to 1866 ft. in the Gantz (U. Dev.) sand. The Federal subsidy of 75¢ per barrel, effective , 1, 1944, which increased to $3.40 the current pipe-line price in this area, seems to have been insufficient stimulus to materially increase drilling for oil, although more repressuring operations are contemplated. Gas The volume of initial open flow of gas developed is off slightly over 10 million cu. ft. from 36 more wells than were completed a year ago, and the average rock pressure of this new gas is more than 100 lb. less than that obtained a year ago. Apparently the best find of this year was reported in Patton township, Allegheny County, where an initial volume of over 4 million cu. ft, was encountered in the Speechley (U. Dev.) sand at a depth of from 3293 to 3303 ft. The rock pressure there, 1190 lb. per sq. in., is nearly virgin. However, this area is fairly well delimited by dry holes and docs not seem nearly so promising from the standpoint of reserves as the Armbrust area, which was discovered several Years ago. In the patton township locality another fair well with 1303 M cu. ft. open flow and 400 lb. Per 59. in. rock pressure completed in the Hundred-Foot (U. Dev.) sand at a a depth of 2125 feet. Armstrong County, as usual, leads in number of producing wells completed with lowest percentage of failures but ranks only fou th in volume of production developed. Only two wells here had more than one million cubic feet capacity, but the rock pessure was under 200 Ib. Per sq. inch. In Fayette County, where the largest portion of new gas was found, activity appears to be shifting eastward. In Luzerne township, four producers having a total combined initial open flow in excess of 10 million cu, ft, were found in the Big Injun (Miss.) sand. The best well was found also in the same area in the Speechley sand (U. Dev.) at a depth of 3460 ft. This was a 2500-M CU. ft. well in Georges township. Several wells of more than a million cubic feet capacity were found in Jackson, Washington, Wayne and Whitley townships, Greene County. None of these, however, was in a new pool.

Jan 1, 1945

By M. A. Selim, W. H. Somerton

Thermal expansions and heats of reaction of three typical sandstones were measured in the temperature range of 25°to 1,000°C. The significance of these data in subsurface heat-transfer calculations is discussed. Linear thermal expansions were measured both parallel and perpendicular to the bedding planes. Volume expansions are reported as the perpendicular expansion plus two times the parallel expansion. Expansion behavior of the sandstones was found to be controlled by the expansion characteristics of the quartz content. Differential expansion of the quartz grains and other minerals included in the sandstones caused permanent deformation of the heated samples after they were cooled to room temperature. Structural damage resulting from heating is probably an important cause of the reduction of thermal conductivity of heated samples. Measurements of heats of reaction were based on the known heat required for a- quartz inversion. Thermal reactions, which probably include deby-droxylation of clay minerals and decomposition of carbonate minerals contained within the samples, were found to require more than one-fourth of the amount of heat necessary to raise the temperature of the rock alone. In shales and limestones, the reaction heat could be substantially greater than that required from specific heat considerations alone. INTRODUCTION In earlier work, l-3 methods of measuring thermal properties were developed and thermal data for several sedimentary-rock types were reported. Data included thermal conductivity, specific heat and thermal diffusivity. In addition, calculations of heat transfer in subsurface formations may require data on the thermal-expansion characteristics of rock and the heats of reaction of mineral constituents. Thermal expansion of rocks is relatively small in magnitucle and, from the standpoint of change in bulk density, has only minor effects on heat-transfer cliaracteristics. Thermal-expansion behavior, however, may have significant effects on the structure of rocks. Differential expansion of different minerals and along different crystal-lographic axes may result in structural damage which could effectively reduce the thermal conductivity of the rock. Many mineral constituents of sedimentary rocks undergo phase or related changes when heated to sufficiently high temperatures. Although some of these reactions (such as the a-ß quartz inversion) are reversible and the heat absorbed is returned to the system upon cooling, many of the major reactions are irreversible. Through certain temperature ranges, the additional heat energy required to complete the reactions may be nearly as great as that necessary to raise the temperature of the rock in the absence of thermal reactions. If the heat requirements for these reactions are not considered, serious errors in heat-transfer calculations may result. Thermal-tzxpansion and thermal-reaction data have been obtained for three typical sandstones. Methods of measurement and results obtained are reported and discussed in the following. THERMAL EXPANSION OF SANDSTONES The linear expansions of three outcrop sandstones (Bandera, Berea and Boise) have been measured in the temptbratue range of 25° to 1,000° C. Expansion measurements were made in the directions parallel and perpendicular to the bedding. The differential expansion apparatus used is that described by Mitoff and Pask.4 The test sample is heated in an electric furnace with a temperature rise of 6°C/minute. The lengthening of the samples upon heating is compared with the small and known expansion of a fused silica rod. The change in length is transmitted to an X-Y recorder by means of a Statham transducer. A maximum error of ± 1.5 per cent has been obtained with this apparatus

By A. Yoshikawa, T. Sugeno

To detenmine the origin of the sharp fatigue limit in many ferrous metals, S-N curvces were determined in push-pull fatigue at 18.6 kc per sec at room temperature and - 67°C for various kinds of iron. These differed in carbon and nitrogen content and grain size (25 and 2500 grains per sq mm). Sharp knees appeared in the S-N curves of fine-grained specimens with high interstitial content at both temperatures. In coarse-gruined specimens, knees were not sharp .regardless of the interstitial content and the testing temperature. It is concluded from these results that the controlling factov for the appeavance of the sharp fatigue limit is not strain aging but grain size. It has already been mentioned that iron and some iron alloys show fatigue curves characterized by a more or less sharp knee and a fatigue limit.' Explanations of the origin of this characteristic behavior of fatigue in iron appear to fall into two broad classes. One is concerned with interstitial impurities through the aging or locking effect and the other is based on intrinsic plastic properties of iron. Levy and sinclair2 and Lipsit and Horne3 have suggested that the fatigue limit observed generally in iron and steel is due to interstitial solute aging during the course of fatigue. On the other hand, Thompson and wadsworthl have suggested that the fatigue limit may be analogous to the sharp yield point, in the sense that alternating stresses above the fatigue limit are necessary to break down the dislocation locking. However, there are some experimental results which cast doubt on the general validity of these suppositions.4-8 Ferro and Montalenti' have recently suggested that the typical form of the fatigue curve of iron seems to come from an intrinsic plastic characteristic of the iron structure. This suggestion is based on the experimental result that pure iron containing an insufficient amount of interstitial solute to alldw appreciable strain-aging effects still showed a fatigue limit at room temperature. Although systematic investigations on the effect of grain size are scarce, it is thought that this effect is important in relation to the sharp fatigue limit. In fact, sensible differences were observed by Oates and Wilson4 in fatigue behaviors of a low-carbon steel depending on grain size. Ideally, the fatigue limit will be defined as the upper limit of stress amplitudes at which the life is infinite. This ideal fatigue limit can never be determined because of the limited time available for experiments, and moreover scattered data points often leave the construction of S-N curves somewhat arbitrary. And, it is usually stated that a material has a fatigue limit when its statistical S-N curve becomes apparently parallel to the N axis with a more or less sharp knee. The meaning of the fatigue limit and the sharp knee will be discussed in detail in relation to the construction of S-N curves. The origin of this sharp knee was investigated by determining S-N curves of iron for various interstitial contents, testing temperatures, and grain sizes. EXPERTMENTAL PROCEDURE The material as received was a commercial-grade low-carbon steel in the form of 4-mm-diameter rods with the following composition in weight percent: C, 0.09; Si, 0.017; Mn, 0.43; P, 0.006; S, 0.012; Cu, 0.11. Five different groups of specimens were tested. The grain sizes and interstitial contents in each group are given in Table I. The specimens of group C-02 were decarburized by annealing for 100 hr at 700°C, followed by an additional 100 hr at 850°C in wet hydrogen. Specimens of groups N-2 and N-9 nitrided in a mixed atmosphere of ammonia and hydrogen after an initial treatment identical to group C-02. The specimens of group C-9 were prepared in a manner similar to those of group C-02, except heat treatment was carried out in a vacuum. After polishing their surface with emery paper, the specimens of all groups were given a final anneal for 30 min at 930°C and air-cooled in an evacuated quartz tube. For group C*-9 this

Jan 1, 1965

By AIME AIME

UNQUESTIONABLY the Coal Division has never had a meeting in which so many outstanding technical papers were presented of immediate practical application to problems of personnel, mining, safety, preparation, combustion, and carbonization. Should there have been those present with the lingering idea that all that was needed for success in the coal industry was a strong back and a weak mind they must have had a rude awakening.

Jan 1, 1942

By Henry Sturgis Drinker, Rossiter W. Raymond

Jan 1, 1914

By Oswald J. Heinrich

The great improvement which have been made in late years in the different systems and instruments used to perforate the crust of the earth for purposes of testing and exploring for mineral resources or for other reasons, by means of bore-holes of greater or less diameter and to greater or less depths, are manifold. It may therefore be of interest to make an impartial comparison of them, or of such as are most commonly used. Being well aware of the difficulties which are encountered in such a task, a reasonable allowance most be made in such a comparison. It is a rare instance when even two decidedly different systems or instruments have been used in the same locality, penetrating identically the same strata to the same depth. The diameter of a borehole as well as its greater or less depth must also be considered in regard to its cost per foot, etc. But for practical purposes, for exploration at least, we may assert this rule: Any bore-hole, of whatever diameter, which allows the means of examining the strata most carefully and completely, will be sufficient for this purpose, but that one which will do it most economically and in the least space of time, must be considered the best for it. It will, therefore, partially depend upon circumstances, what system, in spite of other superiorities, may be the best in each case, and the following remarks may aid in deciding this question. To make the attempt here to review all that has been published upon the different systems and means of boring would be out of place. Reference can be had to the able publications treating upon this subject. A difference in this respect exists in regard to the use of the hollow rods in connection with the diamond drill, used for that purpose. The great future, which appears to be evident for this instrument, will be warrant enough for any one, who has had the opportunity to test it, to give his experience to the public. Only in this way can we bring this system to such perfection, as it seems to deserve and