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By C. A. WARNER

AN OIL and gas mining lease contract, as entered A into by and between 'the lessor and the lessee, contains certain express covenants stipulating, in part at least, the exact performance thereof; it also contains certain implied covenants, among which may be included that of protection of the leased premises against drainage by the drilling of necessary offset wells. In the drilling for, and production of, oil and gas, however, it not infrequently happens that the lessee, acting in good faith, does not deem it prudent to, drill a test thereon even though the location for such test is offset by a producing well on an adjoining lease. Such conclusion, on the part of the lessee, is generally construed by the lessor as constituting a breach of the implied covenant mentioned above, and he may take proper action to secure satisfaction therefor. The action against the lessee is generally for cancellation or relinquishment of the lease, together with, or apart from, claims for damages allegedly sustained through failure to properly protect against drainage of the leased premises.

Jan 1, 1931

By Tracy Jarrett

In 14-karat gold alloys, as in 10-karat gold alloys,3 the addition of such metals as zinc, nickel, copper and silver produces a wide range of physical and chemical proper-ties such as color, hardness, corrosion resist-ance and melting points. These important factors made gold alloys desirable in the optical work and for jewelry. In 14-karat gold alloys, as well as in 10-karat or 12-karat, it is possible to have two golds of the same color, one of which will corrode more than the other, although it may be harder. Some of these alloys have been investigated by F. E. Carter,1 E. M. Wise,5 and L. Sterner Rainer.4 In this group of alloys the gold content of 58.3 per cent (14-karat) was held constant, while the copper varied from 36 to 24 per cent. The balance of the alloy consisted of one, two, or three of the metals silver, zinc, and nickel. All the alloys were melted in an induction furnace and cast into an ingot that meas-ured 3 by 1/4 by 3/4 in. The method of determining the melting points, color deter-minations and acid test have been discussed in previous papers by the author.2,3 It is necessary to use small test bars (Fig. r). The tensile bars were annealed at 1300°F. for 20 min. and then air-cooled. There being a very marked drop when the yield point was reached, "the drop of the beam" method was used in determining the yield point.

Jan 1, 1940

By F. W. Schaller

TETRAGONALITY is an important aspect of the models of transformation, strengthening, and tempering of ferrous martensite. When the c/a

Jan 1, 1963

By J. D. Pennock

The different samples of brick examined were Grecian magnesite, American magnesite; silica brick and coke-oven tiling made in Belgium and used in retort coke-ovens. The Grecian magnesite was furnished by a New Pork party. The American magnesite and the silica brick were furnished by a manufacturing company in Pittsburgh. From these brick were made cylindrical cores, '79 inches long and 15/8 inches in diameter. At one end of each was drilled a hole about 1/4-inch in diameter and 11/4 inches long, into which the thermometer was inserted during the experiment. Conductivity.—The apparatus used for determining the conductivity, as shown in Fig. 1, is a sheetriron drum, 18 inches in diameter and 8 inches high. In the center is a little combustion-chamber with walls of split fire-brick, 39 inches square and about 6 inches high. The fire-brick, however, pass through the drum to the table on which the drum stands. The cores are placed horizontally, half-way between the top and bottom of drum and on the line of diameters at right angles. In the four walls of the combustion-chamber are cut holes just large enough to allow the cores to pass through. The cores extend

Jan 1, 1897

By W. J. Reagan

THE problem of increasing output and decreasing percentage of rejections is a vital one in the manufacture of steel of any kind. The making of basic open-hearth steel for use in rolled steel wheels, tires for locomotive and car wheels, and forgings of various kinds, is a highly specialized industry. The increase in weight of railway rolling stock of all kinds, and the high speed that the public demands of transportation facilities, make it imperative that steel for use in this class of material shall be of the highest quality obtainable. During the past few years it has been the writer's good fortune to have opportunity-to study the defects in basic open-hearth steel, and also the results obtained by various changes in open-hearth practice, on such defects. The opportunity for study and the details available are rarely found in the manufacture of steel of any kind. It seems reasonable to assume that many of the results determined here can be applied to the production of steel of other types with a decided improvement in quality, a decrease in the percentage of rejections and an increase in output. All of the material described is basic open-hearth steel with the following range of analysis: carbon, 0.50 to 0.85 per cent.; phosphorus and sulfur, 0.04 coax.; silicon, 0.15 to 0.35; manganese, 0.50 to 0.75. All of this material is bottom-cast, therefore tapping and pouring temperatures are higher than in top-cast production. Ingots used in this type of work are of standard length with varying diameters. The ingot is known as duodecagonal, or twelve-sided. The standard body length is 88 in. and the hot top length, 14 in. Fig. 1 shows a typical ingot of this type. The diameter varies from 13 to 30 in. Ingots for special forgings, which cannot be made in molds of standard size, are made in molds of various sizes and designs. These ingots are sliced cold, into blocks of various lengths, depending upon the weight of the forging to be made. Fig. 2 shows the ingot-after coming from the slicing lathe. Just sufficient metal remains between blocks to hold the ingot in one piece while it is being removed from the lathe; then steel wedges are inserted between the blocks and the blocks are broken apart. This affords abundant opportunity for inspection, as the interior of the

Jan 1, 1930

By V. A. Phillips, M. Safdar Ali

The tensile properties of Cu-0.20 pct Al, Cu-0.45 pct Mg, Cu-0.27 pct Cr, and Cu-0.22 pct Be solid-solution alloys were studied at -196°, 18°, 2509 and 500°C on wires internally oxidized at 900°and 1000°C. Internal oxidation produced marked increases in yield strength relative to pure copper, particularly at low temperature. The yield strength decreased with increase in temperature to a much greater extent than predicted by current theories of dispersion hardening. The strengthening effect of internal oxidation persisted throughout the entire stress-strain curve, but since a marked loss of ductility occurred at all test temperatures, only modest increases in tensile strength were realized. INTERNAL oxidation involves the preferential oxidation of a baser solute in a relatively noble solvent by diffusion of oxygen into the solid. Since the process is diffusion controlled, it is expedient to carry it out at a high temperature often approaching the melting point. The amount of solute is limited and the oxidation conditions adjusted so that oxygen diffuses inwards to meet the solute causing reaction to progress inwards and form subscale instead of only sur face scale. The reaction can be made to occur throughout the thickness of thin material producing a fine dispersion of oxide inside the metal. C. S. Smith1"3 appears to have been the first to recognize the true nature of the process of internal oxidation. Although extensive kinetic and metal-lographic studies followed by Rhines and coworkers,4-5 Chaston7 andMeijering and Druyvesteyn8 working independently were the first to report hardening effects due to internal oxidation. These results prompted detailed studies of the effects of internal oxidation on the hardness, tensile, creep, and fatigue properties of a number of alloys by G. C. Smith and coworkers9-12 in England, on hardness by Gottardi13 in Italy, and on hardness and tensile properties by wood14 in the U.S.A. Publications dealing with other aspects of internal oxidation will not be reviewed here. Internal oxidation of solutes having a high affinity for oxygen provides a means of obtaining very fine dispersions stable in a suitable atmosphere at temperatures well above those at which most age harden ing precipitates coalesce. The process therefore offers a method of producing thin sheet and wire of possibly outstanding creep resistance. The size limitation might be overcome by internally oxidizing porous powder compacts made from alloy powder before final sintering. PREPARATION OF ALLOYS The alloy ingots, which were approximately 5 1/2 in. long by 1 in. diam, were made up in a high-frequency furnace, using as raw materials OFHC copper, 99.99 + pct Al, high-purity magnesium, and master alloys of Cu-4.19 pct Be and Cu-10 pct Cr. The alloys containing aluminum and magnesium were melted ii closed high-purity graphite crucibles and solidified in the crucible which was lowered partly Out of the coil to give a hot-top effect. The alloys containing beryllium and chromium were made by melting in vacuo in alumina-lined sillimanite crucibles. The magnesium, chromium, and beryllium

Jan 1, 1960

By W. M. Bertholf

IN 1945 tests were made in the coal washery of the Colorado Fuel and Iron Corporation, at Pueblo, Colo., to determine the value of the Humphreys spiral. So far we have demonstrated that it is of definite value to us in rewashing a portion of our table middlings; and we are fairly certain that this is not necessarily the only place in which it can be used to advantage. Because of manpower and material shortages, experimental work has been discontinued for the present. Three of the spirals are being installed for use in rewashing the middlings, and testing and experimental work will proceed when this installation is completed. All evidence secured so far points to the fact that the spiral can make an effective separation of heavy material below 8-mesh; but that it is ineffective in removing larger, heavy material. This, of course, will limit its use to fine coal or a classified feed containing no heavy material larger than 8-mesh. In considering the results of our tests, it should be noted that the feed was our table middling, and that any real separation of this material is a "moral victory," as there is little material that could be properly called coal and practically no heavy rock, the consequence being that previous attempts to clean the middlings have not been at all successful. Several articles dealing with the spiral and its use in treating heavy minerals have already been published,1 but for the benefit of those who have not seen these we include a brief description of the spiral and of the way it operates, taken from Bulletin 4 of The Humphreys Investment Co.: The Humphreys Spiral Concentrator consists of a spiral conduit of modified semicircular cross section. Ore pulp is fed to the top and, as it flows downward, the heavier particles concentrate in a band along the inner side of the pulp stream (Fig. I). Outlets for removal of products are located at the lowest points in the cross section of the conduit. Wash water, added at the inner edge of the stream, flows outwardly across the concentrate band. The width of concentrate band removed at the outlets is controlled by adjustable splitters. Concentrate is usually removed from the upper portion of the spiral and middling from the lower portion. Tailing is discharged from the lower end. Tests are usually made in closed circuit, since this provides a maximum of information with a minimum amount of sample. Fig. 2 shows the spiral set up for closed-circuit testing, and gives a good idea of the general arrangement of such an installation. The small cyclone separator is used to provide clean wash water without introducing additional water into the circuit.

Jan 1, 1946

By C. Kremer Bain

DURING the past several years of diamond drilling in Washington County, Mo., the St. Joseph Lead Co. has discovered a concentration of commercial lead-zinc ore at four different points within an area of 36 square miles. The largest and to date the most promising group of these orebodies is located in the Indian Creek area. It was considered to be of sufficient value to warrant development. The Indian Creek area is in the center of the northern half of Washington County, 11 miles northwest of Potosi, Mo., the county seat. The location is readily accessible from Potosi by car or truck over the all-weather Missouri State Highway No. 114. The topography is one of rolling relief, varying from an elevation of 700 ft above sea level on Mineral Fork and Indian Creek to a maximum of 1176 ft at High Point Tower. It is divided in equal halves between the drainage to Mineral Fork and to Indian Creek. The shaft site at 1060 elevation is on the divide between the two drainage areas. The Indian Creek side is rough and heavily wooded, with only a few cultivated clearings. The slopes to Mineral Fork are more gentle and rounded, with much of the area cleared for farm land. Most of the surface is covered with Potosi and Eminence formations, which show little evidence of any structure. Ore structure was worked out by extensive diamond core drilling, with holes varying in depth from about 700 to 1300 ft. As of Oct. 1, 1950, 218 prospect holes had been drilled within the 36-square mile area. The ore is disseminated galena with considerable accompanying sphalerite in the Bonne Terre forma-tion in the shape of irregular blanket-type deposits. The main controlling structural feature of the outlined mineral zone is a buried pre-Cambrian rhy-olite-porphyry ridge extending partly through the Bonne Terre formation, which laps against the por phyry and also covers it. The mineralized zone parallels and forms an irregular halo around the porphyry ridge and is concentrated in the Bonne Terre formation where the La Motte sandstone is cut out by the porphyry ridge. This is a very common mineral occurrence in the southeastern Missouri lead belt district. The La Motte sandstone, which normally underlies the Bonne Terre formation, is thus cut out entirely. In this area the Bonne Terre is usually about 275 to 320 ft thick, the La Motte varying in thickness from zero up to 400 ft. Commercial concentrations of ore are indicated at several places, the most notable being at the shaft site where an orebody at least 4000 ft long with widths of 500 to 600 ft has been outlined. The total thickness of mineralized rock reaches 150 ft in some holes, although total ore thickness runs from 8 ft to about 60 ft, often in more than one layer. Preliminary Planning Ore reserves as outlined lend themselves to open-stope mining with trackless haulage and mobile loading machines and drilling equipment. This type of equipment has proved to be very efficient during recent years in the company's lead belt operations. After a study of bids for shaft sinking and an estimation of comparative costs, it was decided that the shaft would be sunk by St. Joseph Lead Co. personnel using company equipment. Since the plant site is about 26 miles from the company's nearest lead belt operations, it was necessary to plan a complete surface plant, including mill, shops, office, change room, and warehousing facilities. Immediately following the filing of an application for a certificate of necessity, a headframe was selected for which detailed drawings were already available. The order was placed for fabrication so that it could be delivered and erected in time to serve for sinking the shaft. This eliminated the expense of a temporary headframe. Drilling was started on two churn drill holes near shaft location, and two 1000-gpm deep well pumps

Jan 1, 1954

By J. R. Cahoon, W. V. Youdelis

In a recent publication by Flemings and Nereo, equations for the calculation of the solute distribution in castings were developed, and the solute distributions for unidirectionally solidified A1-4.5 pct Cu ingots cast under various thermal conditions were calculated. The equations derived by Flemings and Nereo for the dendrite "expansion" and "steady-state" zones are essentially equivalent to those previously published by Kirkaldy and Youdelis, 16 for, although the flow velocity cooling rate, and temperature gradients appear in the fundamental differential equations, calculation of the solute distribution requires that the above be explicitly related to the assumed or measured solid-liquid mass distributions during solidification. In the treatment of Kirkaldy and Y-oudelis the mass distributions are simply assumed or measured without any prior and explicit association of the mass distributions to a velocity parameter. The treatment of Flemings and Nereo permits solidification conditions more complicated than the simple unidirectional case to be considered (although in principle the treatment of Kirkaldy and Youdelis could also be extended to include the more general solidification case); however, we note some limitations in the treatment of Flemings and Nereo, and the purpose of this discussion is to point these out and also to indicate those points of similarity in the mass distribution models used which make the two treatments equivalent. Both the Kirkaldy-Youdelis and Flemings-Nereo treatments consider a zone of dendrite "expansion" followed by a "steady-state" zone. However, Flemings and Nereo have failed to consider a zone of "collapse" which begins at the base of the first dendrites to reach the top of the ingot. The omission of this zone of "collapse" results in too high a value for the solute concentration in the latter portion of the ingot to solidify and the conservation of total solute is not possible. In the zone of "collapse" the solute concentration rapidly decreases, which may be accounted for as follows: consider a mushy zone of length X,, shown schematically in Fig. 11 (a), which develops at the chill face and then moves as a steady-state configuration along the length of a solidifying ingot. The solute distribution in this zone, when it first attains the steady state, is shown qualitatively in Fig. 11(b). The segregation is positive (above Co) in the region ab because this region contains primary dendritic solid, ranging from kco to kcE in composition (where k is the partition coefficient and CE is the composition of the eutectic liquid), and liquid metal near eutectic composition. The segregation is negative (below Co) in the region bc because it contains primary dendritic solid only slightly above kco in average composition and liquid metal only slightly above Co in composition. As the zone X, moves as a steady state

Jan 1, 1969

By W. G. Oldham

By monitoring the capacitance of abrupt p-n junctions it is possible to follow the motion of substitu-tional impurities. A p-n junction is formed by growth of silicon from an Al-Si alloy on an n-type silicon sutstrate at a temperature in the range 650" to 750°C. The diodes are etched and sorted for consistent V-I and capacitance behavior and separated into groups. After irradiation, each set with an unirradiated control set is annealed to various temperatltres for 10 mm and the capacitance remeasnred. For very heavily doped diodes (-1019 per cm3) observable capacitance changes occur at neutron fluences of >1015 per cm 3. The results may be interpreted in seceral ways, the simplest of which is to assume simple vacancy diffiision with small impurity -racancy interaction (at the diffiision, i.e. annealing temperature of 700°C). In this interpretation it is found that a typical vacancy makes about 1024 jumps and travels about 10-5 cm before disappearing. The required effective annihilation center density is about 1016per cm3 . Estimates of the vacancy-impurity interaction can be made and the above numbers correctecl, but for arty reasonable assumptions the number of vacancy sinks connot be much reduced. ThE complete annealing of radiation induced defects requires that the vacancies and interstitials either recombine, travel to the surface of the crystal, or travel to an annihilation center, e.g., a dislocation or a precipitate. If the interstitial is ignored except as a possible vacancy annihilation center at low temperatures,* the motion of vacancies may be followed by monitoring the corresponding motion of substitutional impurities. pfister2 has measured the enhanced diffusion of impurities in an asymmetric shallow diffused silicon structure by optically monitoring the junction movement. In these experiments we monitor instead the capacitance of a heavily-doped deep symmetric p-n junction. The sensitivity for this method is several orders of magnitude higher than in Pfister's technique, mainly for two reasons: 1) the junction capacitance of a heavily-doped junction is sensitive to impurity movements in the Angstrom range* com- and 2) the junction may be far from the surface which is a major annihilation center for vacancies. THE EXPERIMENT A p-n junction is formed by the epitaxial growth of silicon from an A1-Si alloy on a silicon substrate at a temperature in the range 650° to 750°C. The technique used is the transport of an aluminum melt through a temperature gradient.4 A 10-mil thick aluminum disc is sandwiched between two silicon wafers and the assembly raised to about 650° C with a temperature gradient normal to the sandwich. After about 8 hr the upper (hotter) wafer has been entirely transported and deposited epitaxially on the substrate wafer. The substrate and overgrowth resistivity are measured with a 4-point probe. The as-grown structure is lapped until the wafer is about 1/2 mm thick with the junction in the center. Contacts consisting of electroless nickel covered by electroplated rhodium are applied to both the p and n sides. The wafer is diced into square dice 1/2 to 1 mm on a side and the dice are etched sufficiently to remove approximately 1 mil of silicon. The following results are all for aluminum (p-side) and antimony (n-side) doped specimens with NA =3x 1018 per cm3, ND = 2-8 x 101A per cm3. The diodes are sorted for consistent V-I and capacitance behavior and separated into groups. After irradiation, each set with an unirradiated control set is annealed and the capacitance remeasured. A special capacitance measurement method is used to insure a low sensitivity to shunt resistance. The diode is voltage driven and the current monitored by a phase lock amplifier. It is possible to adjust the detector phase to a point where shunt resistances as low as 100 O have no effect on the reading. The diodes in this study have a capacitance in the range 1000 to 5000 picofarads and a shunt resistance in the range 100 to l06 O depending on the stage of the anneal. THEORY The theoretical problem is twofold: 1) The computation of the amount of impurity diffusion and hence the impurity profile resulting from a given amount of vacancy motion, and 2) the computation of the capacitance from the impurity profile. A comparison of the theoretical and experimental capacitance (in particular the changes) yields the amount of vacancy motion. Vacancy Motion. A convenient parameter to measure the total amount of vacancy motion is Jv the total number of vacancy jumps per unit volume. Although this parameter varies with position in the crystal, owing to vacancy annihilation at the surfaces, it is approximately independent of position far from the surfaces, i.e. in the junction region. In terms of the number of vacancies per unit volume Nv and the vacancy diffusivity given by

Jan 1, 1970

By W. H. Moore, E. T. Powell

IN the early days of mining in the Anthracite field, only the thicker and better seams of coal were mined, because of the limited mining and coal-cleaning facilities, therefore many of the thinner and less productive seams were permitted to remain unmined. With improvements in mining methods, the introduction of modem preparation plants, and the increased market demand for small-size coal, the thinner and more laminated seams have now become assets. In many instances these seams overlie the mined-out beds of the thicker and better seams, from which all recoverable coal was removed by the conventional breast-and-pillar method of mining. Some collieries in certain sections of the Anthracite field are now relying on these thinner and laminated seams. For the purpose of illustration, a large area in the Hickory Swamp-Ridge Basin of the western middle coal field has been selected, where as early as 1898 the No. 4, or Little Buck Mountain, seam was mined and pillars removed. The No. 5, or Buck Mountain, seam lying on a comparatively light pitch and with intervening strata of but 55 ft. of rock was not mined until 1935. Farther east, in the same basin the Nos. 8 and 9 seams, which are two splits of the Mammoth seam, have been mined and robbed and the workings have been abandoned since 1896. The overlying No. 9 ¾ seam, or the upper split of the Mammoth, and the No. 9 ¾ or 4-ft. seam remained virgin, with only an interval of 50 ft. of rock separating them, and with 40 to 50 ft. of rock strata separating the No. 9 ½ seam from the completely mined area of the Nos. 8 and 9 seams. These seams lie on a pitch of 45° on the south side of the basin and on 75° on the north side of the basin. Mining has been carried on in the 9 ½ and 9 ¾ seams for 3 years on both dips of the basin, for a distance of 3500 ft. In some sections the overlying strata of the thicker seams previously mined have settled without any apparent breaks in the upper strata, as indications have shown in the top split of the Mammoth; while in other areas the roof and bottom of this top split of the Mammoth have settled unevenly, thereby causing the bottom and roof to break into blocks. In attempting to mine over a large area of the No. 5 or Buck Mountain seam, a similar settlement has been encountered; the roof of the seam has been broken and a considerable amount of timbering has been necessary in order to make the mining of the seam possible. The conventional breast-and-pillar method, using shaker conveyors, has been used in the No. 5 seam, and a slant-breast method in the mining of Nos. 9 ½ and 9 ¾ seams. MINING OF LIGHT-PITCH SEAMS The No. 4 seam was mined and robbed by the conventional breast-and-pillar system. In this area the seam pitched from 5° to 25° on the north dip, averaged 8 ft. in thickness and had a slate bottom and a

Jan 1, 1941

By J. H. Nead, T. S. Washburn

The grades of commercial steel produced in large quantities can be divided into two general types from the standpoint of ingot structure— killed and rimmed. Killed steel covers a wide variety with carbon contents throughout the range of the steel portion of the iron-carbon diagram, and is the kind usually used in the production of alloy steels. Rimmed steel is normally associated with carbon ranges under 0.30 per cent, and is not yet used to a large extent in alloy practice, except for copper-bearing steels. The fundamental differences in the ingots made from these two types of steel can be seen most easily in Figs. 1 to 7. In the rimmed ingot shown in Figs. 5 to 7 there are two lines of blowholes approximately parallel to the sides and coming together at the top and at the bottom of the ingot. In the killed ingots shown in Figs. 1 to 4 these blowholes arc not present. Also, the rimmed ingot has no well defined pipe, as compared to the deep pipe on the killed ingots, and there are numerous primary blowholes in the lower portion of the rimmed ingot perpendicular to the surface and close to it, while on the killed ingot there are no blowholes of this type in the ingot shown in Fig. 1 and very small ones close to the surface in the lower part of the ingot shown in Figs. 2 to 4. With respect to the presence of pipe and the primary blowholes, the structure may vary considerably in both rimmed and killed ingots, therefore these cannot be considered as fundamental structural characteristics differentiating the two types of steel. The primary blowholes in rimmed ingots may be much less pronounced than those in the ingot shown in Figs. 5 to 7—as, for example, in "ingot iron," which is entirely free from them. An example of a cross section of an ingot-iron ingot is shown on page 16 of "Research and Methods of Analysis of Iron and Steel," published by the American Rolling Mill Co. (1920). A certain amount of pipe may also occur in rimmed ingots, though it is normally porous and not as well defined [or deep as in the killed ingot of Fig. 1. In killed ingots, primary blowholes may occur near the surface, as in Figs. 2 to 4, and

Jan 1, 1937

By W. H. Hough, P. B. Leavenworth

Development during 1942 led to the discovery of 26 new fields in the Texas Gulf Coast, as compared with 27 during 1941. Of these, 19 are classed as oil fields, 4 distillate fields, and 3 gas fields. Production from the new fields amounted to 614,467 bbl. to October 1942. Producing Sections.—Discoveries in I942, compared with the previous two years, classified by producing formations, are shown in the following table: It is interesting to note the increase in Wilcox discoveries due to the extensive geophysical campaign that has been con. ducted since 1940. Drilling.—During the year 688 wells were drilled, of which 574 produced oil or gas and 114 were dry. This represents a considerable decline in activity over the previous year, when 1405 wells were drilled in the area, of which 1081 were producers and 324 failures. Jackson County continued to hold the lead, with 222 wells completed. Production.—-Despite curtailed drilling, production amounted to 118,009,451 bbl. for 1942, indicating a slight increase over the 113,726,893 bbl. produced during 1941. The statistics in Tables I and 2 include condensate and distillate as oil production, because many Gulf Coast fields produce oils with a wide variation of specific gravities, all of which are commingled in pipe lines. Table 3 shows by counties most of the activities referred to. The number of wells drilled includes only field wells; not wildcats. Outstanding Fields of 1942 The Texas Gulf Coast covered in this report has 270 more or less active oil and gas fields, including the new discoveries of 1942. Of these the most outstanding from the standpoint of production are listed in Table 4. Each of these fields produced one million barrels or more during 1942. Some of the fields where new extensions are occasionally referred to as separate fields, such as West Columbia and New West Columbia, or Thompson and South Thompson, are combined to give a more accurate outline. Two interesting facts may be noted from this list of some 26 oil fields: (I) that the Lolita field, Jackson County, is the only discovery since 1938 to produce more than one million barrels annually, although there have been 79 discoveries since Jan. I, 1940; (2) that 20 of these 26 fields produce from the Frio. New Fields ALief, Harris County.—Pure Oil Company's No. I Mike Albanese was drilled to 8637 ft. in Cook Mountain shale. After numerous tests the well was completed on Apr. 20, 1942, in a Yegua sand at 7919 to 7924 ft. for 54 bbl. of 52' gravity oil and 3,335,000 cu. ft. of gas through

Jan 1, 1943

By W. H. Hough, P. B. Leavenworth

Development during 1942 led to the discovery of 26 new fields in the Texas Gulf Coast, as compared with 27 during 1941. Of these, 19 are classed as oil fields, 4 distillate fields, and 3 gas fields. Production from the new fields amounted to 614,467 bbl. to October 1942. Producing Sections.—Discoveries in I942, compared with the previous two years, classified by producing formations, are shown in the following table: It is interesting to note the increase in Wilcox discoveries due to the extensive geophysical campaign that has been con. ducted since 1940. Drilling.—During the year 688 wells were drilled, of which 574 produced oil or gas and 114 were dry. This represents a considerable decline in activity over the previous year, when 1405 wells were drilled in the area, of which 1081 were producers and 324 failures. Jackson County continued to hold the lead, with 222 wells completed. Production.—-Despite curtailed drilling, production amounted to 118,009,451 bbl. for 1942, indicating a slight increase over the 113,726,893 bbl. produced during 1941. The statistics in Tables I and 2 include condensate and distillate as oil production, because many Gulf Coast fields produce oils with a wide variation of specific gravities, all of which are commingled in pipe lines. Table 3 shows by counties most of the activities referred to. The number of wells drilled includes only field wells; not wildcats. Outstanding Fields of 1942 The Texas Gulf Coast covered in this report has 270 more or less active oil and gas fields, including the new discoveries of 1942. Of these the most outstanding from the standpoint of production are listed in Table 4. Each of these fields produced one million barrels or more during 1942. Some of the fields where new extensions are occasionally referred to as separate fields, such as West Columbia and New West Columbia, or Thompson and South Thompson, are combined to give a more accurate outline. Two interesting facts may be noted from this list of some 26 oil fields: (I) that the Lolita field, Jackson County, is the only discovery since 1938 to produce more than one million barrels annually, although there have been 79 discoveries since Jan. I, 1940; (2) that 20 of these 26 fields produce from the Frio. New Fields ALief, Harris County.—Pure Oil Company's No. I Mike Albanese was drilled to 8637 ft. in Cook Mountain shale. After numerous tests the well was completed on Apr. 20, 1942, in a Yegua sand at 7919 to 7924 ft. for 54 bbl. of 52' gravity oil and 3,335,000 cu. ft. of gas through

Jan 1, 1943

By P. P. Gregory

ESTIMATION of re- serves in prorated sand fields has been discussed by S. A. Judson, H. D. Easton, Jr., and W. A. Schaeffer, Jr., in a paper that appears in Vol. 114 (1935), of the A.I.M.E. TRANSACTIONS. The purpose of this present paper is to extend the investigation to prorated flush limestone fields and to outline a method of procedure in determining the amount of oil originally in place and the amount of oil that can be recovered from such fields. Although it is possible to use the decline curves to estimate the amount of recoverable oil in certain limestone fields that are allowed to produce the oil at or near capacity production, such a method cannot be used in fields under severely restricted production rates. The problem is exceedingly complex due to fluctuation in the allowable rates of oil production over a wide range and at frequent intervals, and especially because of the heterogeneous nature of the reservoir itself. A well completed in a large solution cavity, capable of producing great quantities of oil per day, may be offset by a well of very limited capacity. Also, it is di5cult to arrive at an average figure for porosity in a given limestone reservoir due to abrupt variations in the character of limestone, in many instances even between two ad- joining wells. It is a safe statement that uniformity of porosity and permeability in limestone reservoirs .is nonexistent. It is evident, therefore, that the method of estimation of re- serves on the basis of per-acre content can give only approximate results.

Jan 1, 1935

By G. V. Smith, C. O. Tarr, R. F. Miller

Metallurgists have long recognized that the Fe3C type of carbide is not a stable phase in steel and that, given sufficient time, it will decompose with formation of graphite, at least at temperatures below about 205o°F.l This slow graphitization has never been of much concern to users of hypoeutectoid steels, for in such steels it occurs only during prolonged exposure at elevated temperature. In I935, Kinzel and Moore2 reported complete graphitization of the carbide of a 0. I5 per cent carbon steel that had been in service for about 26,000 hr. at a temperature of about IIOO° to 12oo°F. In discussing this paper, both Mathews and Sauveur reported graphitization of slightly hypereutectoid steels. In an extensive investigation of graphitization of high-purity iron-carbon alloys, Wells1 produced graphite at 7oo°C. (I29o°F.) in an alloy containing as little as 0.13 per cent carbon, and showed that graphite may precipitate either directly from austenite or from decomposition of Fe3C, also that the rate of graphitization tends to increase with increase of temperature, at least up to a certain point, and with the presence of graphite nuclei. Jenkins, Mellor and Jenkinson,3 studying the structural changes in carbon steels ranging from 0.17 to 1.14 per cent carbon during stress-rupture tests at elevated temperature, observed graphite in an aluminum-killed 0.40 per cent carbon steel after fracture in 4340 hr. under a stress of 17,900 lb. per sq. in. at 840°F. and in many of the steels after stress-rupture test at 12oo°F. Unstressed samples of 0.60, 0.86 and I.I4 per cent carbon steels graphitized almost completely in 360 hr. at I200°F., while samples of 0.90 and 1.10 per cent carbon steels were somewhat graphitized, and steels containing 0.24, 0.40 and 0.57 per cent carbon showed no sign of graphite. Their results indicate that graphite precipitates the more readily the higher the carbon content, though this tendency is influenced to some extent by deoxidation practice, and that graphitization is accelerated by plastic deformation. In a recent study of the graphitization of 0.4 and 0.6 per cent carbon steel strip, made by M. A. Hughes,4 it was found that at I2oo°F. graphite appeared after 72 hr. in aluminum-killed but not in silicon-killed steel, and that the rate of graphitization was increased by slow cooling from I6oo°F. and by cold-working prior to annealing. In creep tests of normalized 0.15 per cent carbon steel killed with 2.5 Ib. of aluminum per ton, at the U. S. Steel Corporation laboratory at Kearny, spheroidization and some graphitization were found after 3000 hr. at Iooo°F. under a stress as low as 1500 lb. per sq. inch. .

Jan 1, 1944

By C. O. Tarr, G. V. Smith, R. F. Miller

Metallurgists have long recognized that the Fe3C type of carbide is not a stable phase in steel and that, given sufficient time, it will decompose with formation of graphite, at least at temperatures below about 205o°F.l This slow graphitization has never been of much concern to users of hypoeutectoid steels, for in such steels it occurs only during prolonged exposure at elevated temperature. In I935, Kinzel and Moore2 reported complete graphitization of the carbide of a 0. I5 per cent carbon steel that had been in service for about 26,000 hr. at a temperature of about IIOO° to 12oo°F. In discussing this paper, both Mathews and Sauveur reported graphitization of slightly hypereutectoid steels. In an extensive investigation of graphitization of high-purity iron-carbon alloys, Wells1 produced graphite at 7oo°C. (I29o°F.) in an alloy containing as little as 0.13 per cent carbon, and showed that graphite may precipitate either directly from austenite or from decomposition of Fe3C, also that the rate of graphitization tends to increase with increase of temperature, at least up to a certain point, and with the presence of graphite nuclei. Jenkins, Mellor and Jenkinson,3 studying the structural changes in carbon steels ranging from 0.17 to 1.14 per cent carbon during stress-rupture tests at elevated temperature, observed graphite in an aluminum-killed 0.40 per cent carbon steel after fracture in 4340 hr. under a stress of 17,900 lb. per sq. in. at 840°F. and in many of the steels after stress-rupture test at 12oo°F. Unstressed samples of 0.60, 0.86 and I.I4 per cent carbon steels graphitized almost completely in 360 hr. at I200°F., while samples of 0.90 and 1.10 per cent carbon steels were somewhat graphitized, and steels containing 0.24, 0.40 and 0.57 per cent carbon showed no sign of graphite. Their results indicate that graphite precipitates the more readily the higher the carbon content, though this tendency is influenced to some extent by deoxidation practice, and that graphitization is accelerated by plastic deformation. In a recent study of the graphitization of 0.4 and 0.6 per cent carbon steel strip, made by M. A. Hughes,4 it was found that at I2oo°F. graphite appeared after 72 hr. in aluminum-killed but not in silicon-killed steel, and that the rate of graphitization was increased by slow cooling from I6oo°F. and by cold-working prior to annealing. In creep tests of normalized 0.15 per cent carbon steel killed with 2.5 Ib. of aluminum per ton, at the U. S. Steel Corporation laboratory at Kearny, spheroidization and some graphitization were found after 3000 hr. at Iooo°F. under a stress as low as 1500 lb. per sq. inch. .

Jan 1, 1944

By George Simkovich

It was hypothesized that solid-state point defects should alter the flotation properties of solids. Tests conducted on pure AgCl and AgCl doped with CdC12 show that atomic point defects exhibit an important role in the floatability of AgC1. Tests conducted on PbS doped with Ag2s or Bi2S3, also show that the defect structures resulting from these dope additions, i.e., a combination of electronic and atomic point defects, contribute significantly to the flotation of PbS. IT has been established that flotation occurs only when a finite contact angle exists between a solid and a gaseous bubble.' This angle, measured through the liquid phase, is expressed by the equation where the are inter facial free energies and the subscripts S, G, and L represent solid, gas, and liquid phases, respectively. As is seen in Eq. [I] three interface free energies, sG, sl, and GL, enter into the contact angle equation. Therefore, any variation in these energies which sufficiently varies the contact angle will, in turn, vary flotation processes. Changes made in any of the phases concerned, i.e., gas, liquid, or solid phase, are reflected through the changes occurring in two of the surface energy terms. Thus, a change in the liquid composition would be noted in sL and GL, and it is this phase, the liquid, which is most frequently altered in flotation studies., Changes in the solid phase must be reflected through the changes occurring in the sG and sL terms. In particular, it is hypothesized that changes in the surface concentrations of point defects in the solid-phase will alter the sG and sL terms which, in turn, will be reflected by flotation results. As an illustration of this hypothesis one may consider the defect structure and the flotation of AgC1. The bulk defect structure of AgCl is essentially one involving equal number of cation vacancies and interstitial cations.3 Upon adding CdC1, to AgC1, a greater number of silver ion vacancies are created in the bulk of the crystal.4 On the surface of the crystal the smaller binding forces and the free space accomodations may also allow for the creation of "surface interstitial anions", which will be designated as ad-anions. Thus, the point defect structure of the surface of AgCl doped with CdCl, will consist of cation vacancies and/or adanions. If the molecular forces responsible for the surface energies, ?SG and ?sL, are significantly altered by the presence of these surface point defects, then differences in flotation results will be noted as the concentration of these defects is varied. The defects present in AgCl are predominantly atomic in nature. In the case of PbS both electronic and atomic defects are present.5 This compound conducts electrically by either electrons or electron holes depending upon whether excess lead or excess sulfur is present. Upon disolving BiS3 in stoichio-metric PbS, one increases the concentration of cation vacancies and the number of electron carriers in the bulk of the crystal.5" At the surface, the possibility of ad-anions must also be considered. Conversely, upon dissolving AgS in stoichiometric PbS one increases the concentration of interstitial cations and the number of electronhole carriers in the bulk of the crystal.5,6' At the surface the interstitial cations will be designated as ad-cations. Thus, the point defect structure of the surface of a PbS crystal doped with Bi2S3 will consist of a number of cation vacancies and/or ad-anions and an excess of electrons. Conversely the point defects on the surface of a PbS crystal doped with Ag2S will consist of a number of ad-cations and an excess of electron holes. Again, as in the case of AgC1, should the molecular forces responsible for the magnitude of the interface free energies, ?sG and ?sL, be significantly altered by the presence of these surface defects then significant differences in flotation results will be noted as the concentration of these defects is varied. EXPERIMENTAL To test this hypothesis flotation tests were conducted on pure and doped AgCl and on PbS doped with either Bi2S3 or Ag2S. Preparation of the AgCl samples was performed as follows: AgCl and weighed amounts of CdC1, were melted in a porcelain crucible. The melt was then forced through a capillary tube and the particles emitted solidified in air as they fell about 1.5 meters. Spherical particles, -0.50 + 0.25 mm, were separated from the remaining solidified material

Jan 1, 1963

By J. C. Martin

Stmplified equations are developed for the flow of fluids in gas drive reservoirs in which the effects of gravity can be neglected. The results show that the pressure distribution is governed by a nonlinear heat flow type of equation, and the saturation distributions are related to the pressure by the same equations QS those developed by Muskat for the average pressure and saturations in gas drive reservoirs. Unrler certain conditions the equation for the pressure can be approximated by the linear form of the heat flow equatlon. This equation tk analogous to the equation for the pressure in single-phase compressible flow The analysis reveals that the equation for the pressure in n~ultiphase flows can be obtained directly from the equation for the pressure in slngle-phase flows by simply replacing the single-phase compressibility by the total compressibility and the single-phase mobility by the sum of the mobilities of all the fluids present. Perrine's method of pressure buildup analysis for multiphme flows is based on these same substitutions. Thus, the development presented in this paper constitutes a theoretical justification for Perrine's method of pressure buildup analysis. One of the most difficult problems associated with the production of oil is the determination of the flow of the fluids within the reservoirs. One purpose of this paper is to present the development of simplified equations for the flow in gas drive reservoirs. The other purpose is to present some of the needed theoretical foundation for the methods currently being used in the analysis of multiphase pressure buildup data. The analysis presented in this paper makes use of a partial linearization of the equations governing multiphase flows. It is felt that the process of linearizing or partially linearizing the nonlinear equations of multiphase flows can lead to useful results since this process has proved extremely valuable in the study of other fields of science and engineering where nonlinear equations are encountered. Pressure buildup data of shut-in wells have been used for many years to estimate the static reservoir pressure. These data have also been used in studying the aver- age permeability both away from and close to the well-bores. The majority of the buildup data are obtained from wells producing two or three fluids. As yet the theoretical foundations for the methods of buildup analysis used in connection with rnultiphase buildup data have not been established. A number of methods of analysis of pressure buildup data have been developed." Most of these methods apply only to single-phase flows, and almost all of the theoretical analysis is confined to single-phase flows. Perrine' developed a method of analysis for rnultiphase flows from the method for single-phase flows of Miller, Dyes, and Hutchinson.' He did this by simply replacing the single-phase compressibility by the multiphase compressibility and replacing the single-phase mobility by the sum of the mobilities of the fluids in the rnultiphase flows. Obviously, such a procedure lacks a certain amount of theoretical justification, and such practices can lead to erroneous results. Fortunately, Perrine's results have a theoretical justification, and this justification is presented in the following discussion. It is assumed that gravitational effects and the cornpressibility of the rock can be neglected. Under these assumptions the equations governing the simultaneous flow of gas, oil and water in porous media areo* The preceding equations can be expanded into the following expressions.

By I. C. Edwards, G. E. Agar

INTRODUCTION Many research efforts over the past years have been devoted to the study of energy consumption in comminution and the characteristics of the broken material. The old "laws" have been superseded by more general methods of analysis1,2,3 but these methods have not received much attention outside the laboratory. The work to be described here was done in order to obtain scale-up information on wet rod milling of sylvinite. EXPERIMENTAL A 30 x 51 in. Denver rod mill with a scoop feeder was used for these tests. Ore was fed from a variable speed screw conveyor into the feed box along with saturated brine. The mill was filled to approximately 45% of its volume with 2400 lbs of a mixed rod charge. The minimum possible feed rate was 2.5 tph and the practical maximum for this mill was 8 tph. Individual tests were run by setting the solid feed rate, then adjusting the brine flow rate to give the desired pulp density. After steady state, as evidenced by constant discharge pulp density, had been reached, samples of the discharge were taken at 15-minute intervals. These samples were filtered, washed with alcohol, dried, then screened on Tyler screens using a Ro-tap shaker. The sylvinite feed was regular plant feed that had been scalped at 20 mesh and was tapped from the coarse ore bins. It had been previously passed through a roll crusher set at 3 inches and after scalping was essentially minus 1 in. plus 20 mesh. RESULTS The screen analysis of samples from each series of tests was plotted on double logarithmic scale paper to determine the reliability of the series. In some cases, a faulty sample or screening procedure dictated that the results of one test be discarded. The criterion is a simple one — if the slope of one plot was noticeably different from the others in the series, it was discarded. The only cases that caused difficulty were those in which the brine was not thoroughly displaced from the solids. When this occurred agglomerates were easily identified on the screens and the whole of the sample was retained on 3 or 4 screens. There were no border line cases. The number N given in Table 1 is the number of size analyses that were pooled to form the data shown in Fig. 1. While examining the reliability of the sizing and sampling by plotting the data, it became apparent that there was no significant difference between grinds made at 50 and 60% solids. For the analysis given here, these tests were regarded

Jan 1, 1967