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By L. C. Snider

NO important discoveries of petroleum during 1932 are reported from Canada. New Brunswick, which has a small production from one field, was inactive, and the production showed a decline from 6600 bbl. in 1931 to about 6300 bbl. for the year 1932. The old fields in Ontario increased from 123,000 to about 131,000 bbl. Alberta showed a decline of more than one-third, from 1,413,631 bbl. in 1931 to about 913,000 bbl. in 1932. This decline was due principally to the restrictions placed on the flow of gas wells in the Turner Valley field, from which the crude naphtha is obtained that accounted for more than 93 per cent of the production of Alberta and for more than 80 per cent of the production of all Canada in 1932. The starting of new wells to the limestone that produces the naphtha-bearing gas was prohibited late in 1931, and only wells started before that time were finished during 1932. One well was drilled in the Turner Valley field to a depth of 7555 ft., establishing a depth record for Canada. It passed out of the Madison limestone at 5560 ft., and encountered showings of oil in the underlying formations, probably of Devonian age. Commercial production had not been established by the end of the year. Commercial oil wells were brought in in two areas in Ontario which had previously been considered as productive of gas only— in the Dawn gas field, Lambton County, and in Raleigh Township, Kent County. The discovery wells had initial productions of about 50 bbl. per day, but no production of major importance is indicated. In Alberta, outside the Turner Valley district, two wildcats were drilled northwest. of Lethbridge in the Keho Lake vicinity. Both failed to make commercial producers in the Madison limestone, but one was testing upper sands at the close of the year. Good showings of oil are reported. A very small production was found in the Madison limestone in a wildcat well on the Twin River structure southeast of Lethbridge and another well has been started near by on what is considered on geophysical evidence to be a better location structurally. About 15 locations were made on the Canadian side of the border north of the Cut Bank development in Montana.

Jan 1, 1933

By H. W. Paxton, G. M. Pound

A method is outlined for taking into account variation in chemical potential of both components in evaluating capillary effects at growing interfaces. The results are compared with experiment, and seem to be in reasonably good accord for Widman-statten ferrite growing in austenite. ENERY pointed out that during the steady-state growth of phases with a rather small radius of curvature at their advancing edge capillarity cannot be neglected. By proper application of the Laplace equation a correction must be made to the activity gradients down which diffusion occurs. Subsequent workers have concerned themselves with attempts to evaluate specific cases by the use and modification of the principles laid down by Zener.2-5 To solve the problem in its simplest form it is necessary to assume thermodynamic equilibrium at the interface and to select some criterion which will allocate the available free energy between reversible and irreversible processes. Zener chose to assume that the division should be made such that the new phase grew at the maximum rate. Other workers have used the same2,3 or different assumptions, e.g., maximum rate of free-energy dissipation,4 minimum rate of entropy production.5 Li6 has proposed that the "thermokinetic potential" should be a minimum at steady state. The purpose of this presentation is to note that most prior treatments have considered variations due to capillarity only in the chemical potential of the mobile constituent, and that a more consistent treatment must involve a consideration of the variation of chemical potentials of both solute -and sol- vent in a binary system.* As an example, the way in which this arises for ferrite growing from austenite may be illustrated by reference to Fig. l(a). The line OABC shows a typical variation of carbon activity with composition at one atmosphere pressure (at a transformation temperature below A3). In the tip of a growing ferrite plate with a hemi-cylindricab leading edge of radius ?, the pressure due to capillarity is*

Jan 1, 1963

By T. O. Massalski, J. D. Ayers

A massive transformation, 0 —am, takes place in a number of copper-based systems where the ß phase field at high temperatures extends to compositions that are slightly less solute-rich than the limits of the a phase field that exists at lower temperatures. Consequently a solid-state transformation becomes possible that does not involve a change of composition. Within this narrow range of composition the massive am phase can be usually produced in two ways: by a fast quench from the ß phase through the a phase field, or by pulse heating into the a phase field of an undecomposed ß phase retained at room temperature by a prior quench. In the Cu-Ga system the occurrence of a massive am phase has been also observed in alloys whose composition falls outside the equilibrium a phase field1 but not in the Cu-Zn system.2 We have recently observed the occurrence of the ß — am transformation also in two silver-based systems, Ag-Zn and Ag-Cd. The a and 0 phase fields in these systems again slightly "overlap" in a narrow composition range. In the Ag-Zn system this range falls between 36.7 and 40.2 at. pct Zn, and in the Ag-Cd system between approximately 41 and 42.5 at. pct Cd. Alloys were prepared from high-purity materials and cast in quartz tubes under inert atmosphere. No significant change of composition occurred during casting. After homogenizing in the 0 phase field, small pieces of each alloy were reheated at the homogenizing temperatures for a few minutes and quenched into various media. There were examined metallographic-ally after removal of surface layers that may have suffered from contamination or from the loss of the solute element. In the Ag-Zn system extensive areas of the am phase (identified by selective etching, observation of the slip trace variants, and occurrence of twinning) were observed in a comparatively low-zinc alloy (37.8 at. pct Zn) for all quenching media employed: iced

Jan 1, 1969

By Walter Stephen

MODERN developments in alloy steels have been so rapid and diverse that engineering practice has scarcely had time to re-appraise all items of past experience wherein conclusions became axiomatic under conditions that no longer apply. A case in point is the wet screening of abrasive ores within the fine range still looked upon as belonging exclusively to classifiers. By virtue of the development of stainless steels (18 per cent Cr, 8 per cent Ni), it is no longer true that classifiers are more economical than screens in closed circuit with large-tonnage ball or rod mills at 65 or even 100 mesh, provided a selective overgrind of the higher-gravity constitu-ents of the ore is not desired. Wet screening of ores is a highly corrosive as well as an abrasive opera-tion, because of the inevitably high degree of oxygenation of the water. Screen cloth of ordinary or spring-steel wire almost at once becomes pitted and covered with a film of corrosion products, which causes rust-blinding of fine-mesh screens and offers high frictional impedance to the flow of ore particles. On the other hand, the well-known properties of stainless steel enable it to maintain a bright surface, and so to eliminate blinding either by ore particles or by corrosion products. That a large-tonnage mill grinding hard ore to 65 mesh can be oper-ated economically in closed circuit with screens instead of classifiers has recently been demonstrated at the Copper Cliff concentrator of the International Nickel Co.; in the test to be described, a 6 ½ by 12 ½ -ft. Marcy rod mill ground from 625 to 820 tons. of ore per day to approxi-mately 65 mesh, operating in closed circuit with three 4 by 5-ft. Hum-mer screens, without any classifier.. Stainless-steel cloth gave an indicated life of several months. There was no difficulty with blinding, yet dilution and spray water could be controlled so that screen undersize averaged not less than 40 per cent solids. In contrast, ordinary carbon steel was pitted and blind with rust within 40 hours.

Jan 1, 1938

By J. D. Kalasky

Continuous mining has revolutionized the coal industry but intensified the problems of earlier mechanization. From the installation of the first miner, it was recognized that face ventilation would be one of these problems. To establish an efficient work cycle for the equipment being used, conventional mechanized mining provides four or more development faces. Continuous mining, relying on a single machine, requires only one face, although more than one can be driven alternately by the same machine. In gaseous areas mined by the older methods, the intermittent rate of exposure allows time for the face to bleed off or be cleared, and the width obtained with conventional units makes it possible to hang a brattice line almost to the face. Continuous mining increases the ventilation hazards; there is no margin of time, and very limited space. For all practical purposes, continuous miners available today can be grouped into two major types, rippers and borers. The two can be further classified, respectively, as flexible and rigid. Both types have been in operation in U. S. coal mines for the past five to ten years in a number of seams, under various conditions ranging from slightly gaseous to very gaseous. Common methods of face ventilation utilizing jute or plastic brattice material for line curtains, stoppings, and checks have so far met with success. Air volumes to operating sections are greater than for conventional mining, and specific instructions have been given to section crews stressing the precautions needed in dealing with a steady rate of gas emission and the importance of maintaining reasonably air-tight brattice to direct a good steady flow toward the face at all times. Operators of continuous miners, as well as the foreman on each section, are equipped with an approved safety lamp for gas testing. When the miner is in steady operation, tests for gas at the face are made at 15 to 30-min intervals, depending on the

Jan 1, 1960

By V. R. Garfias

It has been repeatedly questioned whether estimates of oil reserves are of any practical value, as the greater number of such calculations previously made have subsequently been proved to be grossly inaccurate. But even admitting partial justification for such statements, it must be evident that some idea, however approximate, of the available reserves of essential minerals is of vital importance in mapping their development and the future trend of the related industries, particularly if it is kept constantly in mind that these estimates—which are never intended as a final word—must be continually subject to revision in accordance with the changes in their component factors. The value of these estimates, therefore, hinges on the clear understanding that they can only apply within the limited time when the controlling factors remain unchanged. It should be understood, however, that while estimates of possible and probable oil deposits are as a rule but idle conjectures, appraisals of proven oil reserves can undoubtedly be made with an ever-increasing degree of accuracy. And it is with this in mind that in the present study the endeavor has been to estimate only the world's proven oil reserves—the oil that yet remains underground in the producing fields—and their logical extensions, and to leave out of consideration the questionable volume of the probable and possible oil reserves. In Table 1 the countries at present producing oil in commercial quantities are listed in the order of the magnitude of their proven reserves. As shown in the table, the world's proven oil reserves are estimated at over 24 billion barrels, while the total production to the end of 1932 aggregates nearly 23 billions. Past production represents, therefore, 48 per cent, and proven reserves approximately 52 per cent of the total. About 61 per cent of the reserves are located in the American continent and close to 33 per cent in the Near East fields of Russia, Iraq and Persia. It is interesting to note that the proven reserves in the important producing regions almost equal if not exceed their production to date. The Mexican fields are a remarkable exception in this respect since they produced over 135 billion barrels and have proven reserves estimated at only 300 million barrels.

Jan 1, 1933

By H. W. Camp

Although the situation in the oil industry during the past year has not been conducive to large expenditures for development and research, there is little indication that such expenditures have been curtailed. While few outstanding achievements have been reported, considerable progress has been made in the development of new product,s and the adaptation of petroleum derivatives to new uses. The most important question facing the refiner today is the antiknock quality of his gasoline. This year has seen the widespread adoption of the term "octane number" as a measure for anti-knock values, and in the latter months of the year the public has been made acutely aware of this condition through competitive advertising. Gasoline is no longer priced on volatility and gravity alone, but on octane number as well; and premiums are being paid for material of relatively high octane rating. The situation has grown more and more competitive and has forced refiners continually to raise the octane rating of their regular and competitive grades, and at this writing the same situation exists for premium grades which have possessed relatively high anti-knock properties for some time. Straight-run gasoline produced from paraffin-base or semiparaffin-base crudes has an inherently low anti-knock value, and in order to convert this material to a higher quality it has been found necessary to crack an increasing percentage of the crude oil charge. By completely cracking the heavier portions of the crude and blending back with the straight-run gasoline, it has been possible to produce an average of 63 to 65 octane number gasoline on average Mid-Continent crude. This operation carried to the fullest extent does not suffice, however, and the recent and rapid development of the so-called '(reforming unit," has resulted. The straight-run gasoline fraction is cut into two parts: a light, low boiling point gasoline; and a heavy gasoline or naphtha. The latter containing the low anti-knock portions of the gasoline, is sent through a re-forming unit and subjected either to high temperature or pressure, or both, which materially increases its octane number. On average Mid-Continent the blend of low boiling point straight-run,

Jan 1, 1932

By Edward Keller

Although the subject matter contained in this paper is presented under a new title, its writing was induced by the work of S. Skowronski and K. W. McComas.' A discussion of the latter is here combined with the presentation of new and independent data. The' physical constants quoted by the authors of that paper, such as melting and boiling points, as also the chemical reactions of the substances involved, are so well established that the numerous confirmatory experiments and their application to metallurgical conditions leave little or no room for criticisms. On the contrary, they will greatly aid to dispel any lingering skepticism as to possible considerable losses of copper accruing when the metal is melted in the presence of its own and, probably, other chlorides and when no provision is made for the recovery of volatile products. Exception may be taken, to some degree, to that part of the work under the caption Melting Drillings of Copper Mixed with Sodium Chloride. These experiments should have been extended in order to make the implied reactions clear and the results convincing. The latter are stated to be, "that when sodium chloride is present above certain minimum quantity relative to copper some of it is found to volatilize in the melt while another part reacts with the metallic copper to produce the volatile cuprous chloride, and that when smaller quantities of sodium chloride are present the reaction is complete and all chlorine is found to have volatilized as cuprous chloride." Metallic copper and sodium chloride are mentioned as the sole reagents in this chemical process, acting, according to the authors, in a neutral atmosphere of carbon dioxide. The chemist, quite naturally, wi11 inquire into the formula according to which that reaction takes place and will find that it presents itself as follows: 2Cu + 2NaCl = 2Na + Cu2Cl2 It would appear that the truth of this formula will be challenged and a more rational explanation of the reaction sought. Apparently, carbon dioxide is neutral relative to metallic copper in its molten state; whether it remains neutral in the presence of sodium chloride is quite another

Jan 1, 1921

By Wilbur A. Nelson

All of our accounts say that the discovery of copper ore at Duck-town, Tenn., was made in August, 1843, yet it would appear that samples of copper from this district were found by DeSoto, when he wandered into southern Tennessee, in 1539, in his four years of exploration through the Southern States. The following quotation is taken from his diary: "Towards the north there was a province named Chisca; and that there was a melting of copper, and of another metall of the same colour, save that it was finer, and of a farre more perfect colour, and farre better to the sight, and that they used it not so much, because it was softer. And the selfe same thing was told the governor in Cutifa-Chiqui, where we saw some little hatchets of copper, which were said to have a mixture of gold. But in that part of the country it was not well peopled; and they said there were mountains, which the horses could not passe; and for that cause, the governor would not goe from Cutifa-Chiqui directly quicker." DeSoto sent two of his company to try to find these mines, but after five days' wandering through the mountains they returned, stating that their guides had become lost. Although the Ducktown area may have been known to the ancient Indians, the copper deposits were actually discovered in August, 1843, when a Mr. Lemmons, while panning for gold on Potato Creek, in the Ducktown basin, found some reddish-brown decomposed rock. His disgust on finding that this yellow metal was not gold was so great that he did not try to develop his find. In March, 1847, B. C. Dugger erected an iron forge at this same place, but was unable to work the iron as it contained so much copper that on cooling it would break to pieces. The finding of copper in the iron ore by Mr. Dugger led to further explorations; and in April, of the same year, A. J. Weaver, who was passing through that country, told the people that the black rocks they had dug out were rich copper ore. Mr. Weaver began the

Jan 1, 1925

By Charles Legrand

The power plant of the Burro Mountain Copper Co. is located near Tyrone, N. M., at 5,950 ft. elevation. It is interesting because it uses the largest stationary Diesel engines in the United States. The general layout of the plant is shown in Figs. 1 and 2. The building is of steel-frame construction with hollow-tile walls and corrugated-iron roof; the floor is concrete and all windows have steel frames, making a fireproof building. The building is made to accommodate one more electric generator unit which is being installed; also two 4,000-cu. ft. air compressors direct-connected to three-cylinder engines with the same size cylinders as the electric units. The power plant consists of two 815-kva., 60-cycle, three-phase, 6,600-volt, 180-r.p.m. generators, direct-connected to five-cylinder, two-cycle Diesel engines; the necessary circulating pumps for cooling water, cooling towers and oil storage tanks. A portion of the power is used in the same building as the generating units to run one of two 200-kw. rotary converters delivering 260-volt direct current, and a 2,500-cu. ft. air compressor, delivering air at 95 lb. pressure, direct-connected to a 400-hp., 6,600-volt, three-phase synchronous motor. The remainder of the power is used to run a 1,500-ton concentrating mill 3 ½ miles from the power house, various hoists, pumps and motors about the mines and the lighting and water-works of the town of Tyrone. The direct current is used for electric traction in the mine, also to run hoists and motors that were installed before the new power plant was built. Due to the large hoists that take starting peaks of 250 kw. and the 10-ton electric locomotive that takes at times 150 kw., the load is extremely variable, as shown in. Fig. 3.

Jan 9, 1916

By H. B. Goodrich

In considering historically oil development in Oklahoma, it must be recognized that basic evolutionary factors interlock and have an effect in common throughout the whole oil industry, regardless of locality or minor problems. Oklahoma, as the third in rank of oil-producing states (Texas being first and California second in production for 1929) has, like the rest, advanced to at least a partial recognition of the words, "Conservation," "Unitization," "Curtailment," "Prora-tion," and especially "Cooperation." Whether through altruism (of which there have been examples) or by exercise of good business common sense, Oklahoma operators realize that the oil business can run itself by cooperative action for the good of all. In this long-continued period of overproduction, Oklahoma has brought the advancing output down to limit of market requirements at least temporarily. Sources of Statistical Data For this paper, figures published by four recognized authorities were consulted. Between themselves these vary only a negligible per cent, in their totals. To be consistent, and on account of earlier availability the estimates published by the Oil and Gas Journal are mainly used herein, supplemented from other public and private sources. General Oil ProdCction in Oklahoma In 1927 Oklahoma's peak of all years was 276,022,024 barrels. In 1928 Oklahoma's total production was 247,500,851 barrels. In 1929 Oklahoma's total production was 252,229,474 barrels. The efforts of proration and curtailment programs on flush and semi-flush districts such as Greater Seminole, Oklahoma City, Logan County and others, with the natural decline of older pools, kept 1929 below 1927, but still the total was greater than in 1928. The total United States production for 1929 is herein taken as estiiated at 1,004,266,723 bbl.† Oklahoma produced 25.1 per cent. Of

Jan 1, 1930

By Hillary W. St. Clair

An equation is derived for the rote of reaction of a sphere of metal oxide in a restricted enclosure through which a reducing gas is flowing. The equation takes into consideration the reaction rate coefficient, transport through the gas and through the porous shell of reduced oxide, the rate of gas flow, THIS paper describes a mathematical study of the chemical and physical processes that determine the rate of reduction of solid metal oxide with a reducing gas. The study was a part of a theoretical study leading to the development of a mathematical model for the simulation of the thermochemical behavior of the iron blast furnace. An essential feature of such and the volume of- space surrounding the sphere available for gas flow. The equation is applied to experimental data on vote of reduction of iron oxide in hydrogen. The equation serves as a model for predicting the course of reduction of a particle of. metal oxide in a shaft furnace. a model is an adequate mathematical relationship defining the rate of reaction in terms of all the important chemical and physical phenomena that affect the rate of reaction. This includes not only the reaction rate coefficients, equilibrium ratios, gas composition, and temperature, but also the relevant physical properties of the oxide, rate of gas flow, and relative volumes occupied by gas and solid. In many previous experimental studies of the rate of reduction of oxides by hydrogen or carbon monoxide, the rate of reduction was assumed to be controlled primarily by the chemical reaction at the

Jan 1, 1965

By Eben E. Olcott

The Mine.-For some years attention has been drawn to the copper deposits of the Appalachian range of mountains, and especially to those in that portion crossing the corners of Virginia, North Carolina, and Tennessee. Certain it is that in many places in this locality available deposits of copper await the miner, and one after another are being opened and worked. The parts of these three States alluded to are but sparsely settled, and communications are insufficient to meet the demand for transportation. Railroads are wanted, as the existing wagon roads are unfitted for heavy hauling; these circumstances increase very much the difficulties in the way of mining enterprises. Notwithstanding this, the success of some of the mines of this section is an established fact, and Ducktown has for some years held a high rank among the copper-producing localities of the United States. Of all these deposits, however, none is more interesting or more deserving of attention than the one now under consideration. The works of the Ore Knob Copper Company have been energetically pushed forward, since the reopening of the mine, in the spring of 1873, by Mr. J. E. Clayton, the superintendent and one of the chief owners of the property, and if one thing more than another can insure success it is the combination in this gentleman of rare business capabilities with the deepest personal interest in the pros¬perity of the undertaking. The copper vein -at Ore Knob* is a clearly defined fissure traversing the gneissic rocks of Pre-silurian age in a direction 61° east of north. * The reader is referred to a paper by Dr. T. Sterry Hunt, in the second volume of the Transactions of the Institute, on the "Ore Knob Mine, and some related Deposits," pages 123 to 129.

Jan 1, 1875

By W. J. Feuerstein

STRUCTURAL imperfections in crystals, in recent years, have received the attention of metallurgists concerned with single-crystal properties. Certain etching solutions cause local variations in the rate of etching at dislocations.' Dislocations are expected to be preferred segregation sites for impurities' and Dash" has shown that precipitation of copper occurs preferentially at edge-type dislocations in silicon. Diffusion rates along dislocations are probably higher than rates through more perfect crystalline regions.' These and other phenomena which may be influenced by dislocations may be studied by revealing dislocations as etch pits. This study was undertaken to develop an etch solution for silicon crystals to reveal low-angle grain boundaries associated with dislocation arrays and also etch pits with good contour definition. Additional etches have been reported by Dash," Vogel and Lovell.T rystals were sectioned on crystal lographic planes at various angles from the growth direction for microscopic examination of the etch pits. Experimental Crystals of 75-100 g mass and 3 cm diam were oriented and cut on crystallographic planes. Crystals were grown by Czochralski technique from a quartz crucible. Lapped wafers were chemically polished in a modified CP-4 etch for 1 min (bromine was deleted from the etch solution). The polished wafer was then etched* at room temperature for 5 min. The use of larger amounts of H2O and/or CH2COOH slows the reaction. The Cu(NO3),.3H2O was added to increase the reaction rate and give more definition to the etch pits developed. Some pertinent features concerning the attack of this etch on silicon can be summarized as follows:

Jan 1, 1959

By Raymond B. Ladoo, C. A. Stokes

T is unfortunate that the word "economics" has -¦¦ come to mean, in the minds of many people, a sort of half-baked mixture of New Deal philosophy and bookkeeping. It may mean anything from mine cost keeping to the theory of gold as a monetary standard. As applied to the industrial mineral industries as a whole it means to us an integrated study of all of the technical, geographical, market, financial, and other factors which determine whether or not a given enterprise has a sound chance of making a business success. Of course it is impossible to generalize too freely in this large group of industries which go to make up the nonmetallic minerals. This group includes such dissimilar products as crushed stone and ca- pacitor mica, phosphate rock and spinning fiber asbestos, roofing granules and potash salts, borate minerals and monumental granite. Yet in many respects their economic problems are similar and, at the same time, far different from those of the metals and of petroleum and coal. These basic differences are almost never recognized by people outside the industries and are rarely appreciated even by metal mining engineers. But in many instances these economic factors are fully as important as, if not more important than, technologic problems. It has been a long fight to get an intelligent and wide-spread appreciation of sound technology in the nonmetallic mineral industries. The importance of the economic side of the problem has yet to be widely understood and appreciated. The problem was outlined in considerable detail by one of the authors some 18 years ago in a long series of articles* and he has since prepared numerous talks

Jan 1, 1951

By Oliver C. Ralston, James Norman

DIATOMACEOUS earth occurs in deposits widely distributed throughout the nation. The chief producing areas are in the Western States, where many high-grade deposits are known. Eastern deposits of diatomite are unsatisfactory for many purposes either because of impurity or because of the extremely fine particle size. Eastern users of diatomite, on the whole, must pay for transportation of the material from the west coast. The freight rate is necessarily high because of the great bulk of the diatomite. A satisfactory process of purifying the diatomaceous earths of Maryland and Virginia, which are unsuited for wide use only because of impurities, should be of value to eastern users. In the past, benefication of diatomite by wet processes has been limited to classification or sedimentation for the removal of sand from diatoms. Calcination with salt is used to produce a white diatomite when iron is present in the impurities, and small amounts of clay are rendered inactive in the process. No treatment has been developed whereby a large proportion of clay can be removed from a low-grade diatomaceous earth to give a diatomite of very high purity. In August 1937 the Federal Bureau of Mines, in cooperation with Dr. R. C. Williams, of Baltimore, undertook the problem of purifying low-grade Maryland diatomite by Froth flotation. Work was done at the Eastern Experiment Station, College Park. Unless otherwise stated, the crude diatomite used was from the Patuxent River deposits near Dunkirk. This material, consisting of roughly one-third each or clay, quartz sand and diatoms, was representative of the usual low-grade marine diatomite found in the Coastal Plain Miocene beds of Maryland and Virginia and sporadically in other Atlantic coast states. As received, it contained 50 to 60 per cent moisture and probably had been wet since its formation.

Jan 1, 1942

PHILIP D. WILSON,* Warren, Ariz. (written discussiont).-Mr. Tovote's idea of attempting to classify according to their broad geologic relations the ore deposits and prospects of the Southwest is an admirable one. Attempts have been made to evolve some comprehensive scheme of classification that would be of practical assistance in determining the possible value of prospects, but the ore deposits are too varied in type, form, genesis, and distribution to lend themselves readily to any definite, scientific pigeon-holing. The classification Mr. Tovote recommends, combining the age of the mineralization with the type of the rock supposed to be its source, is open to criticism even on the evidence he presents. The age of many deposits is not nor can be definitely determined because of the absence of sedimentary rocks in their vicinity. Furthermore, the character of the mineralizing solutions has, in a large majority of cases, no relation to the composition of the associated igneous rock. While the solutions may have originated in the same magma, they were usually a much later manifestation of it, often appearing after the intrusive rock had completely solidified and been subsequently crushed and fractured, and in many cases the chemical difference is very marked. It is true that igneous activity in the Southwest is definitely related to-certain geologic periods. The statement, however, that no ore deposits can unmistakably be referred to periods earlier than late Cretaceous is not supported by fact. The bonanza copper orebodies of the Jerome District are definitely pre-Cambrian. As suggested by J. R. Finlay,1 they are probably post-Beltian or late Algonkian in age, perhaps related to the same great mountain-making period as the copper deposits in the Keweenawan series of Lake Superior and the Sudbury, Porcupine, and Cobalt deposits of Ontario. The proof that they are pre-Paleozoic may be summarized as follows: 1. The pre-Cambrian complex in which they occur is overlaid by a great thickness of Paleozoic sediments with the Tonto or Tapeats sandstone at their base. The only primary mineralization in these sediments is an economically unimportant one connected with very recent basalt. 2. In the United Verde Extension mine, the gossan over the great orebody extends to the old pre-Cambrian surface where it is directly

Jan 2, 1919

By G. C. Gester

Oil has been produced in Persia and India for many years, but it was not until 1932 that Arabia entered the arena as a potential oil-producing area. In 1930 the Standard Oil Co. of California acquired a concession covering the rights of exploration and exploitation for oil in the Bahrein Islands and in June, 1932, the first commercial production was discovered by the bringing in of a well known as Jebel Dukhan No. 1 on the Island of Bahrein. Since then the Standard Oil Co. of California through its wholly owned subsidiary, The Bahrein Petroleum Co. Ltd., has been carrying on a systematic survey and development program of its concession in the Bahrein Islands. This group of islands, of which Bahrein is the largest, is in the southwestern portion of the Persian Gulf, approximately 25 miles from the mainland of Arabia. Although geographically a part of Arabia, the islands are not a part of the Kingdom of Saudi Arabia. Their government is essentially independent but certain special rights have been granted to Great Britain through a series of treaties. The Island of Bahrein is 32 miles long by 9 1/2 miles wide and covers an area of 215 square miles. Approximately three-fourths of the island is occupied by a relatively low, broad, elliptically shaped dissected hill, the central part of which is slightly depressed with inward-facing cliffs but culminating in the Jebel Dukhan (Hill of Smoke), which rises to an elevation of 443 ft. above sea level. The topography of the island is a good index of its geologic structure. Structurally the island is an elongated dome or quaquaversal fold composed of rocks of Eocene age. The major axis of the fold strikes N.5W. All of the topographic high portion of the island is a part of the structural uplift. The crest of the fold is broad and flat with the dips increasing on the flanks. How far tilted strata may continue beyond the line where the Eocene beds are covered by recent sands and detrital material is not known. Superimposed on the general structure are a few small irregularities in the form of minor folding and faulting. There is, however, no evidence of any major faults. The largest of the irregularities lies to the south of Jebel Dukhan and has the appearance of a sink

Jan 1, 1934

By E. Baker, David Donoghue

Legal and legislative matters constituted the outstanding features of proration in Texas in 1932. From East Texas emanated most of the political, legal, technical and industrial activity. Conroe and Thompson developed into fields of major importance. Proration orders were issued by the Railroad Commission on many of the producing fields of the Gulf Coast and West Texas not covered in previous years. In Yates, Penn Pool, Winkler, Van, the Panhandle, North Texas and West Central Texas there were 110 changes of importance, except in allowables. New proration schemes were introduced in East Texas, Conroe, Thompson, Saranosa, Government Wells, Tuleta and Howard-Glasscock. Little progress was made in administration or technical development. Legal and Legislative Matters Proration first began in Texas in 1927 as a voluntary attempt to divide the market outlet of a field on an equitable basis. The statutes then in existence were considered somewhat archaic and the Railroad Commission's authority was limited. Subsequent efforts to strengthen the laws were not wholly successful. The 1929 Conservation Act made no mention of market demand but declared that the term "waste" did not mean " economic waste." With the passage of the Pipc Line Act of 1930, providing for ratable purchasing, it was the opinion of many lawyere that a legal means of proration had been found. The 1931 law had ths same provision as that of 1929 with respect to economic waste but specifically prohibited limiting of production to market demand. The law passed Nov. 12, 1932, omitted reference to economic waste and specifically provided for limitation of production to reasonable market demand. Vigorous attacks were being made in State and Federal Courts on the constitutionality of the laws and the validity of the Commission's orders. In Peoples Petroleum Producers, Inc. et al. vs. Lon A. Smith et al., which had been heard before a three-judge U. S. District Court in Houston on May 28, 1932 and again on Sept. 19, the Court's decision for plaintiffs, released Oct. 2, influenced in a large measure the calling of the Legislature and the passage of the Market Demand Law on Nov. 12.

Jan 1, 1933

By H. K. Shearer

The principal events in the oil history of south Arkansas, north Louisiana and Mississippi in 1930 have been: In Arkansas, very little activity, except for discovery of deep oil production at Urbana, and completion of the first oil well in Miller County. In Louisiana, continued development of the Zwolle area, bringing production up to about 10,000 bbl. per day; practically complete development of the Carterville oil-producing area; discovery and drilling of the rather disappointing Holly area, and discovery of Trinity gas production at Sugar Creek, Claiborne Parish and Rodessa, Caddo Parish. In Mississippi, discovery of the Jackson gas field, in Hinds and Rankin counties. Proration of oil runs was not put in effect in these areas during 1930, because the natural decline of the older fields brought production below the demands of local markets. The only effect of the oversupply and low price of oil was the curtailment of some drilling which might otherwise have been done. Drilling in Arkansas reached the lowest stage since the discovery of oil, with less than 100 completions. Louisiana showed some increase in drilling over 1928 and 1929, but almost half of the wells were drilled primarily for gas rather than oil. As no review on north Louisiana production has been prepared since 1927, and there was none on south Arkansas for 1928, the developments of the three years, 1928, 1929 and 1930 are here briefly discussed.

Jan 1, 1931