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By Matthew Kowalczyk, Steve Bloomer, Peter Kowalczyk

"Mineral deposits found near seafloor hydrothermal venting are of great economic interest. Valuable metals such as gold, copper, zinc, and other polymetallic sulfides are found in appreciable grades in seafloor massive sulfide (SMS) deposits associated with these vents. For mapping these deposits, electromagnetic prospecting is one geophysical method that is very useful because copper/gold rich deposits are highly conductive.Ocean Floor Geophysics (OFG) in 2008 developed the first EM system to successfully map the limits of conductive mineralization in a survey at the Solwara 1 deposit (Kowalczyk, 2008). Since then, towed coincident loop time domain systems have been developed by Waseda University (Nakayama and Saito, 2016) and have successfully detected known mineralization buried at 30m depth. Using a deep tow controlled source electromagnetic (CSEM) array, very clear anomalies have been measured (Murton, 2017) over known mineralization at the TAG field on the mid-Atlantic ridge.In 2014 and 2015, OFG partnered with Fukada Salvage and Marine Co. Ltd. and the Scripps Institution of Oceanography to map methane hydrate deposits off the coast of Japan using a towed controlled source electromagnetic (CSEM) system developed by Scripps. These hydrate deposits are resistive targets, and the Scripps system successfully mapped subsurface electrical resistivity distributions to depths of several 100 metres below the seafloor. OFG is attempting to extend the Scripps CSEM technology to map subsurface conductive SMS deposits to a similar range of depths below the seafloor."

Jan 1, 2017

By Alf Thidemann, Per Marius Nilsen

Tunnelling with hydraulic drills has been a success in Norway. In the fall of 1976 excavation of tunnels for the development of the Aabjoera scheme was started. Two and a half years later a total of 25 kilometers of tunnels are completed. During the most busy period 5 rigs with hydraulic drills were in operation. GENERAL INFORMATION. Aabjoera Hydro Electric Plant is located in the central part of Norway (Fig. 1). The scheme covers a mountaineous area between the Tosen Fiord and the valley of Namdalen. Water from the area of precipitation is transferred through 5 tunnels to the main reservoir. From here the water is conducted via a 10 km long, unlined supply tunnel down to the Kolsvik power station. The power station is situated underground with a short tailrace tunnel out in the fiord. Average head of water is 507 m. The Aabjoera plant is jointly owned by Helgeland Kraftlag A/S, 8650 Mosjøen and Nord-Trøndelag Elektrisitetsverk, 7700 Steinkjer. The Civil Engineering Division of the latter company has acted as Consulting Engineers for the scheme. General contractors for the whole scheme has been Ing. F. Selmer A/S, Box 6035, Etterstad, Oslo 6.

Jan 1, 1979

By Sydney H. Ball

A QUARTER of a century ago, a pessimistic Belgian financier in conversation with the founder of the Belgian Congo, that great ruler, Leopold II, emphasized the danger to the colony should the synthesis of rubber be discovered. The king replied, "I do not worry. The Congo has had its ivory period; it now has its rubber period. Tomorrow it will have that of its mineral wealth; eventually that of agricultural products." That "tomorrow" arrived some twenty years ago. Through her mines the Belgian Congo has survived the present depression, and her mines for the next decade will safeguard her. The Congo, in turn. is the surest foundation industrially and financially of Belgium itself. In few, if any, political units is mining as dominant as in the Belgian Congo. In 1930, 1931 and 1932 mineral products represented respectively 67.9 per cent. 70.5 per cent and 59.3 per cent, of the total exports. In 1933 for each white person in the colony, there was produced about $1,675 worth of gold, diamonds, copper, tin ore and minor mineral products and in 1930 the per capita production, notwithstanding the larger population, was almost $2,000.

Jan 1, 1934

By M. Govinda Raj, S. Sridhar, M. Aruna

Hand-transmitted vibration (HTV) exposure is associated with various health risks for operators of mobile mining equipment (MME). The case–control research was conducted to determine the musculoskeletal disorder (MSD) risks associated with exposure to HTVs in the exposed (case) and non-exposed (control) groups. HTV readings were measured at the interface between the hand and the steering device using the SV 105B triaxial hand accelerometer connected to the SV106 human vibration analyzer involving 40 MME operators in accordance with ISO 5349:2001 guidelines. A questionnaire survey was also carried out among both the study groups using Cornell Musculoskeletal Discomfort Questionnaire. The European Union's 2002/44/E.C. was used to assess the health risks posed to the MME operators. Twenty-eight out of the 40 MMEs were generating HTVs exceeding the stipulated daily limits of vibration, putting 70% of the operators at increased risk for developing MSDs. The case group was found to have an elevated risk of exposure with odds ratio (OR) 7.56 (95% confidence interval (CI), 1.159, 49.39) and OR 12.80 (95% CI, 2.436, 67.285) times more likely than the control group to suffer discomfort in the left shoulder and left wrist, respectively, indicating increased risk of exposure to HTV. Additionally, cases had elevated risk associated with exposure to tobacco, OR 9.35(95% CI, 1.856, 47.129) compared to those who did not use tobacco. MSDs were more prevalent in the case group compared to the control group. This observation was validated by the field investigations and the responses of MME operators to the questionnaires.

Aug 2, 2022

Exploration by AS&R of the Nuestra Senora lead-zinc-silver property, located in Cosala District, Sinaloa, Mexico, has proved sufficient ore to warrant placing the mine on an operating basis. Installation of mine plant, concentrator, and townsite, is expected to commence late in 1951. Opening of a lead-zinc property in Nigeria is also being contemplated by AS&R. Private enterprise is being urged by Secretary of Interior Chapman to start a synthetic fuels industry, it is reported. Based on tests at the Louisiana, Mo., plant which produces quality gasoline at costs up to 144 per gal, he predicts that a commercial plant would pay for itself in 10 years.

Jan 4, 1951

By Anthony Iannacchionc, Jessica Benner, Harold Miller, Megan Witkowski

"Longwall bituminous coal mining has been practiced in Pennsylvania since the 1970""s. Hundreds of longwall panels have been mined during the last 40 years but only 24 have actually undermined Pennsylvania's Interstate Highway System. The impact to interstate highways are summarized in this paper and the factors that influence the magnitude of these impacts are examined.INTRODUCTIONOver the last 30 years, interstate highways in Pennsylvania have been undermined by portions of 21 bituminous coal mine longwall panels. From 2003 to 2008, three of the panel were extracted by the Emerald Mine and six by the Cumberland Mine both in Greene County and both owned by Alpha Resources. Previous assessments of longwall mining under Pennsylvania’s interstates have identified impacts to the highways but no danger to public safety. In general the magnitude and extent of impacts during the recent undermining of Interstate 79 or 179 appears to be similar as those identified in previous studies. The nine longwall panels are among some of the widest in the U.S. They are supercritical in character with overburdens ranging from greater than 152 m (500 ft) to less than 305 m (1,000 ft).The Pennsylvania Department of Environmental Protection (PA DEP) requested that the University of Pittsburgh summarize observations collected by their staff during the recent undermining of 179. Observations and photographs of impacts to the highway were made by PA DEP staff and entered into reports prepared by California District Mining Office (COMO) staff and statements written into the Bituminous Underground Mining Information System (BUMIS) database. In addition to the observations by the PA DEP, the Pennsylvania Department of Transportation (PennDOT) conducted a series of detailed land surveys along portions of the highway undermined from 2003 to 2008. To characterize the subsidence basin fanned by longwall mining. PennDOT information has been analyzed by another research group within the university (Guticrre7, et al., 20 I 0)."

Jan 1, 2010

By Anders Sellgren, K. Hansson, A. Jedborn

In the mining industry, conversion of fine particles into a slurry is often part of the normal processing of the ore. Therefore. from a system's point of view, slurry transportation would be considered as a natural alternative, all the way from the working face to the final processing. In underground mines, there is sometimes a considerable inflow of ground water that has to be pumped out. When the mine dewatering installations are integrated with a hydraulic hoisting system, the cost of power needed to pump out the ground water can be excluded from the cost of hoisting, compared with other modes of transporting the solids to the surface. The chief advantage of hydraulic hoisting is that the hoisting capacity can be increased at comparatively low total cost without necessitating the sinking of new shafts. Alternative examples include deepening of the existing mechanical hoisting system, truck, or conveyor belts transport in ramps to the present level. These often become very expensive. The economic effectiveness of hydraulic hoisting and hydraulic design considerations have been discussed by Kostuik (1965) and Sellgren (1985, 1986) for both small shallow mines and large deep underground mines. Objective and scope The objective of this study was to demonstrate the feasibiliy of hydraulic hoisting in hypothetical examples of mine deepening. Underground grinding to a maximum particle size of about 700 um (about 25 mesh) is considered. The pumping of ground ore products with positive displacement plunger or membrane type of pumps at working pressures of up to 15 MPa (2200 psi) is a thoroughly tested technique (Venton, 1986). Hydraulic hoisting system A hydraulic hoisting system is described schematically in Fig. 1. The ore is mined, handled, and crushed conventionally. It is then ground wet underground. The slurry is then temporarily stored in an agitated tank and pumped to an agitated receiving tank on the surface. The ore is then further processed in the concentrator. The capacity of a pipeline is very high. For example, an annual production of 500 Kt (550,000 st) of ore can be handled in a 100-mm-diam (4-in.-diam) pipeline. Systems layout - economic effectiveness Schematic mine layouts are presented that represent situations where hydraulic hoisting often is the most economical alternative. A situation where the ore is trucked to the level of the existing hoisting system is shown in Fig. 2 (following page). With hydraulic hoisting, only a shaft for ventilation, pipe- line, and personnel are needed. In a first phase (Fig. 2). a hydraulic hoisting installation with crushing and grinding units, storage facilities, and pumps has been located at a level of about 400 to 600 m (1310 to 1970 ft) below the surface. With further development of the mine, the hydraulic hoisting

Jan 1, 1990

By M. C. Fuerstenau, J. D. Miller

The response of calcite to flotation with saturated fatty acids and alkyl sulfonates of various chain lengths is presented. The amount of collector re-quired for flotation is shown to decrease systemati-cally with increasing carbon content from 8 to 12-carbon atoms per molecule. This systematic flotation response is correlated with the solubilities of the calcium-collector salts, which were established with a nephelometer. The 14-carbon collectors deviate from this systematic behavior, and no flotation is possible with the 16-carbon homologs. As determined by infrared analysis, the mechanism of collector adsorption involves a specific chemical reaction be-tween the collector and the surface. A reaction of the form CaCO3(s)+ 2 RCOO"=*=Ca(RCOO)2(s) + C03= is suggested. The pH of the system is also shown to be a most important parameter as it controls the carbonate, calcium, and collector ion concentrations in solution and thus controls flotation response. The importance of hydrocarbon chain length of collectors was recognized early, and various studies have been made on this aspect of flotation. Wilkinson, ' for example, noted that as the chain length of alkyl xanthates is increased, the amount of collector required for flotation of sphalerite is decreased. The same effect has been shown in the flotation of galena.2 Similar results were obtained when malachite3 and calcite4 were floated with various fatty acids. DeBruyn5 has shown that a similar phenomenon occurs when quartz is floated with amines at constant pH. Recently, Fuerstenau, Healy, and Somasundaran6 correlated this phenomenon with the van der Waals cohesive free energy of association of the hydrocarbon chains. It seems unlikely, however, that chain association could be involved in the sulfide and carbonate systems with the collector additions employed, especially with the short-chain xanthates. Rather, it would seem that the decrease in collector concentration with increase in chain length noted for flotation is related to the solubility of the metal-collector salt. The purpose of this investigation is to verify this premise and also quantify this phenomenon if possible. Calcite was selected for study with both alkyl sulfonates and saturated fatty acids as collectors. EXPERIMENTAL MATERIALS AND METHODS The collectors used in this investigation ranged from 8 through 14 carbon atoms per molecule. The fatty acids had a reported purity of greater than 99%. The sodium alkyl sulfonates were provided by the Marathon Oil Cot, Littleton, Colorado, and had the

Jan 1, 1968

By Antonio de Lucas, Juan Francisco Rodríguez, Ignacio Gracia, Mª Teresa García

"The amount of waste of Polystyrene (PS) foams is increasing in last years due to their use in insulation, protecting and, storing many different food products. Conventional methods of recycling such as crushing and shrinking by heated air or frictional heat have the disadvantages of molecular degradation, resulting in a reduction of the quality of the recycled polymer. Dissolution and shrinking with suitable solvents is one of the cheapest and more efficient ways of polystyrene recycling but in the process of the solvent recovery by distillation a certain degree of molecular degradation is produced. In this way, CO2 supercritical technology appears as an interesting alternative for the elimination of solvent. This work proposes a global process to polystyrene recycling in two steps: a polystyrene dissolution with a suitable “green” solvent followed by its elimination by supercritical tecnologhy. In order to develop a “green process” the constituents of essential oils, limonene, terpinene, cymene, and phellandrene, are selected as the most appropriated solvents. Introduction In the last years, disposal of the non-biodegradable plastic wastes has been recognized as a serious environmental problem. Recycling these wastes has great interest in order to prevent the environmental pollution and to preserve natural sources (1, 2, 3). Since the Polystyrene foams (PS) is one of the most used foam in isolation, protecting and food storage most of recycling work is concerned with this polyolefin (4). The two main alternatives for treating polymer wastes are energy recycling, where wastes are incinerated, and mechanical recycling (5). Environmental argumentations such as toxic emissions are building up a public resistance against incineration process (6). Mechanical recycling is a popular recovery path for manufacturers and is carried out on single-polymer waste streams. Any way, the market for recycled products can only be found if the quality is close to that of the original. Unfortunately the process of classification and further recovery of these wastes makes them often more expensive than virgin plastic (7, 8). Solvent extraction is one of the cheapest and more efficient ways for PS recycling. If it is done in house of waste producers the separation between plastics could be easy and effective and the transport costs would be eliminated."

Jan 1, 2008

By M D. Raine, J K. Bartlett, S C. Dominy

The Bendigo Goldfield is located in the state of Victoria, Australia, and is one of a number of fields that make up the Central Victorian Goldfield. Since 1993, Bendigo Mining NL has been carrying out an extensive re-evaluation of the goldfield and is currently well advanced in developing an underground mine. The sediment-hosted auriferous quartz reefs are structurally complex and closely associated with anticlinal axes and reverse faulting. The gold within the quartz reefs is characterised by both its coarse nature (100 up to >5000 ¦m) and its erratic distribution; as a result, the Bendigo Goldfield is classed as an extreme nugget effect system. This characteristic ensures that the Bendigo mineralisation is very challenging to sample and evaluate. In this case, diamond drilling is a good measure of structure and geological continuity, but a poor measure of grade and grade distribution. Drilling, combined with on-reef development, bulk sampling and detailed geological studies are required for resource evaluation. For grade control a balance has to be sought between sample representativness, cost, turn around time and practicality. Extreme nugget effect deposits like Bendigo, require the use of bulk samples in order to be representative. However, the cost and turn around time is significant. As a result, a micro-bulk sampling system has been introduced that attempts to overcome these problems by providing a fast, practical method that can define ore from waste. Bulk sampling and on-vein development are still necessary for resource and reserve estimation.

Jan 1, 2003

By T Laurencont

The Queensland Department of Natural Resources and Mines (NR&M) accepted the environmental liability for the Mount Morgan minesite in 1991. This gold and copper mine located 38 km southwest of Rockhampton had been in operation for more than 100 years. Mining leases are still active while the feasibility of a reprocessing operation is carried out. From 1993, NR&M have operated a seepage interception pumpback system which has reduced the chronic load of acid rock drainage (ARD) to the adjacent Dee River, a tributary of the Fitzroy River system. In early-2000, it was recognised that a ten-year plan for rehabilitation of the mine, along with significant funding would be required if a long-term sustainable rehabilitation strategy was to be implemented at this minesite, ultimately making the seepage interception system redundant. A rehabilitation planning workshop coordinated by NR&M was held in May 2000. This workshop brought to the mine a range of technical expertise and key stakeholder groups. This workshop provided a technical forum for review of studies undertaken and to identify priority projects, which needed to be undertaken in the future to more clearly define contaminant sources on the mine site and to prioritise the rehabilitation program. Stakeholder consultation enabled the project team to be clear on community and other government (eg Environmental Protection Agency) expectations. It is clear that the future of the economically depressed community of Mount Morgan will be reliant on the careful management of the significant heritage values at the minesite for tourism, education and research. In the first year (2000), priority studies were initiated, which included whole of site studies on water balance, contaminant sources and a review of occupational health and safety and environment of the minesite and conservation and heritage scoping. Baseline vegetation and soil materials surveys were also initiated. The outcomes of these studies helped to shape the work program for the following year, while providing a basis for an additional funding application, which was granted. The second year of studies focused on building upon the existing baseline studies completed. In addition, studies focussed on addressing the priority issue of contingency planning for overflow from the open cut pit in accordance with best practice management of release water and river monitoring strategies were completed. Completion of these projects over the next six months will enable the optimal rehabilitation strategy to be defined in 2003. This optimal strategy may require the use of a water treatment plant for part of the ten-year program to provide space in the open cut pit for the deposition of ARD contaminant sources (eg waste dumps, tailings). It is envisaged that some sources will be rehabilitated insitu while others will be relocated to the open cut pit. Implementation of this strategy will be dependent on subsequent funding.

Jan 1, 2003

By Henry D. Hibbard

THIS article aims to clarify the use of some terms often occurring in writings on iron and -steel, and also to suggest several new short abbreviated names for some of the things related to the subject which now are indicated by phrases. Crude or Crude Iron The name crude or crude iron is recommended for the iron produced from ore by the blast furnace. When necessary it can be specified as pig iron when in the form of pigs (usually cold), or as molten iron, commonly called hot metal to distinguish it from cold iron in pigs. The product of a direct process of making wrought or malleable iron from ore is not included.

Jan 1, 1924

By Scott SD

The 1986 PACLARK Expedition established that propagation of a seafloor spreading zone into continental crust has created a complex series of volcanic basins on the floor of the Western Woodlark Basin. In addition to abyssal basalts, felsic volcanic rocks were recovered - especially at the leading edge in the extreme west. A recent deposit of hydrothermal Fe-Mn oxides was discovered on an axial seamount of basaltic andesite, and seawater plume anomalies suggest current hydrothermal venting elsewhere. As a modern analogue for the settings in which ancient volcanogenic massive sulfide orebodies probably formed, the Western Woodlark Basin warrants further investigation.

Jan 1, 1987

By Reamy Joyce

Conditions in underground mining are so variable that in approaching the problem of the economies effected by the use of pressure-treated mine ties and mine timbers, it is necessary to secure specific data for each mine. Facts must first be dug out to show the service life of untreated timber and the reason for its failure. Generally speaking, decay is the usual cause of failure, but in some mines mechanical destruction is an important factor. Occasionally the two causes combine to produce fail-urrs, and it is difficult to determine positively which factor is responsible. In making comparisons, it is always necessary to start with the cost in place and for this reason there must be accurate information covering the labor cost of installation and the labor cost of renewals. When treated timber is used, it is necessary to know the specifications for the treating process, whether the timber was painted, dipped, treated open tank, or impregnated under pressure according to standard specifications. It is also necessary to know the preservative used and the amount of the preservative that was retained by the timber after treatment. It is also well to know whether the timber was thoroughly air-seasoned before treatment or was green at the time it was treated. The kind of timber available, both untreated and treated, must be known and all of the factors listed above must be taken into consideration in the study of any problem. Variable Conditions A study was made recently of the untreated mine ties used by a bituminous coal company in two of its mines, which are about 20 miles apart. The mine ties were secured from the same sources for both mines. A careful check was made over a 10-yr. period on the life of untreated main-haulage ties, and it was found that in the mine where the haulage roads were on intake air the average life was approximately 5 yr., while in the other mine, where the haulage roads were on return air, the average life was 2 yr. A similar variability in untreated timber

Jan 1, 1940

By Reamy Joyce

Conditions in underground mining are so variable that in approaching the problem of the economies effected by the use of pressure-treated mine ties and mine timbers, it is necessary to secure specific data for each mine. Facts must first be dug out to show the service life of untreated timber and the reason for its failure. Generally speaking, decay is the usual cause of failure, but in some mines mechanical destruction is an important factor. Occasionally the two causes combine to produce fail-urrs, and it is difficult to determine positively which factor is responsible. In making comparisons, it is always necessary to start with the cost in place and for this reason there must be accurate information covering the labor cost of installation and the labor cost of renewals. When treated timber is used, it is necessary to know the specifications for the treating process, whether the timber was painted, dipped, treated open tank, or impregnated under pressure according to standard specifications. It is also necessary to know the preservative used and the amount of the preservative that was retained by the timber after treatment. It is also well to know whether the timber was thoroughly air-seasoned before treatment or was green at the time it was treated. The kind of timber available, both untreated and treated, must be known and all of the factors listed above must be taken into consideration in the study of any problem. Variable Conditions A study was made recently of the untreated mine ties used by a bituminous coal company in two of its mines, which are about 20 miles apart. The mine ties were secured from the same sources for both mines. A careful check was made over a 10-yr. period on the life of untreated main-haulage ties, and it was found that in the mine where the haulage roads were on intake air the average life was approximately 5 yr., while in the other mine, where the haulage roads were on return air, the average life was 2 yr. A similar variability in untreated timber

Jan 1, 1940

By M. J. Ferrante

Relative enthalpies of high-purity disodium hexatitanate (Na2Ti6013) were measured at the Bureau of Mines to provide new thermodynamic data needed to advance the technology of materials. Measurements from 298.15 to 1,478 K were made by drop calorimetry with a copper block. Tabulated values are listed for the standard relative enthalpy, heat capacity, en-tropy, and Gibbs energy function between 298.15 and 1,500 K. Enthalpy data are also given in equation form and are combined with thermodynamic data from the literature to derive values of standard enthalpies of formation, Gibbs energies of formation, and logarithms of the equilibrium constants of formation. Similar calculations were made for the reaction of Na20 with Ti02.

Jan 1, 1986

By George Steintveit

Det Norske Zinkicompani A/S was established in 1924, on the initiative of the Compagnie Royale Asturienne des Mines. Experimental electrothermic zinc production was carried out on industrial scale for a two-year period, but the problems of electrothermic smelting were not solved. A license for the electrolytic zinc production process was then obtained from the Anaconda Copper Mining Co. A plant for electrolytic zinc production was built, near the small fjord town of Odda in Hardanger, West Norway, The production was based on zinc ore from Spain, and cheap local hydro-electric power. The plant came into operation in 1929. Annual capacity, 36,000 tons. In 1964 a long-term agreement was concluded with Boliden AB by which Det Norske Zinkkompani is secured the raw materials basis for an expansion of the annual capacity to 100,000 tons of zinc, Since World War II, the company has been pursuing extensive research and development programs. As a result, various sections have been rebuilt: nev unloading and storage facilities, a 250 ton per day Fluid Bed Roaster with contact plant, new continuous leaching system, integrating the Jarosite Residue Process, new solution purification section - upgrading the solution quality for a 600 Amp/m2 current density Tank Room operation -, installation of induction furnaces for cathode melting with casting machines and automatic stacking of slabs. Simultaneously, instrumentation, and methods of automatic control have been developed and introduced, providing conditions for optimal plant operations.

Jan 1, 1970

By Jr. D. C. Williams, D. V. Carter

The four new oil-field discoveries made in the East and East Central Texas districts during 1941 were the East Long Lake field, Anderson County; Pickering field, Shelby County; Pleasant Grove field, Rusk County, and Tri-Cities field, Henderson County. The discovery of oil production in the Pettit lime of the Lower Glen Rose was made in the Groesbeck (Barron) field in Limestone County and the Willow Springs field in Gregg County. Important extensions were made to the Pittsburg field, in Camp County, the Chapel Hill field, in Smith County, and the Hawkins field, in Wood County. The Hawkins field was extended sufficiently to more than double the number of proved surface acres. As usual the East Texas field led the district in the number of completions for the year. The second most active field during the year was the Hawkins field, with 250 new wells completed. The third most active was the Long Lake field, in which 50 wells were completed. Approximately 964 wells were completed in the district during 1941. Production and Probation The district is credited with having produced 163,566,695 bbl. of oil and distillate during the year. This represents a decrease of 4 per cent from the 170,424,685 bbl. of oil and distillate produced during the preceding year. The production of 130,378,620 bbl. of oil and distillate from the East Texas field represents 79.7 per cent of the total production of the district; that is, 6.3 per cent less than the production for the year 1940, The district had an estimated basic daily allowable of 614,982 bbl. of oil on Dec. 31. Approximately 33 per cent of the state's annual production was produced in the district, compared with 34.9 per cent for 1940. Since the majority of the fields in this district are subject to proration, any change in the annual production is attributable largely to changes in proration schedules and number of shutdown days. Fields subject to shutdown days were closed in for 113 days during the year, with the exception of the East Texas field, which was shut down 111 days. An order was promulgated by the Oil and Gas Division of the Texas Railroad Commission for encouraging the disposal of salt water and reservoir-pressure maintenance in the East Texas field. Discoveries Tex Harvey Oil Company'sNo. I S. E. J. Cartmel was completed as the discovery well for the East Long Lake field, Anderson County. Production was found in the Woodbine sand, the horizon from which the Long Lake field produces. The Pickering field, Shelby County, secures its production from the Nacatoch sand, found at an approximate depth of 1510 ft., in A. E. McKiernan's No. I, Pickering Lumbering Co. This field is in an area near the state line in which a number of relatively unimportant and

Jan 1, 1942

By Jr. D. C. Williams, D. V. Carter

The four new oil-field discoveries made in the East and East Central Texas districts during 1941 were the East Long Lake field, Anderson County; Pickering field, Shelby County; Pleasant Grove field, Rusk County, and Tri-Cities field, Henderson County. The discovery of oil production in the Pettit lime of the Lower Glen Rose was made in the Groesbeck (Barron) field in Limestone County and the Willow Springs field in Gregg County. Important extensions were made to the Pittsburg field, in Camp County, the Chapel Hill field, in Smith County, and the Hawkins field, in Wood County. The Hawkins field was extended sufficiently to more than double the number of proved surface acres. As usual the East Texas field led the district in the number of completions for the year. The second most active field during the year was the Hawkins field, with 250 new wells completed. The third most active was the Long Lake field, in which 50 wells were completed. Approximately 964 wells were completed in the district during 1941. Production and Probation The district is credited with having produced 163,566,695 bbl. of oil and distillate during the year. This represents a decrease of 4 per cent from the 170,424,685 bbl. of oil and distillate produced during the preceding year. The production of 130,378,620 bbl. of oil and distillate from the East Texas field represents 79.7 per cent of the total production of the district; that is, 6.3 per cent less than the production for the year 1940, The district had an estimated basic daily allowable of 614,982 bbl. of oil on Dec. 31. Approximately 33 per cent of the state's annual production was produced in the district, compared with 34.9 per cent for 1940. Since the majority of the fields in this district are subject to proration, any change in the annual production is attributable largely to changes in proration schedules and number of shutdown days. Fields subject to shutdown days were closed in for 113 days during the year, with the exception of the East Texas field, which was shut down 111 days. An order was promulgated by the Oil and Gas Division of the Texas Railroad Commission for encouraging the disposal of salt water and reservoir-pressure maintenance in the East Texas field. Discoveries Tex Harvey Oil Company'sNo. I S. E. J. Cartmel was completed as the discovery well for the East Long Lake field, Anderson County. Production was found in the Woodbine sand, the horizon from which the Long Lake field produces. The Pickering field, Shelby County, secures its production from the Nacatoch sand, found at an approximate depth of 1510 ft., in A. E. McKiernan's No. I, Pickering Lumbering Co. This field is in an area near the state line in which a number of relatively unimportant and

Jan 1, 1942

By John E. Conley

The production of lime by the burning or calcination of limestone, including all varieties from true dolomites and magnesian limestones to high-calcium types, continues as one of the essential basic industries. In 1937, a total of 4,124,165 tons of lime valued at approximately $30,091,000 was produced in the United States.' The importance of any contribution to our knowledge on the mechanism of the lime-burning process is, therefore, obvious. The burning of limestone has been practiced since the earliest days of our civilization, and the literature on the various phases of the industry is voluminous. Calcination of the various types of limestone has been studied by many previous investigators, but some points require additional research. Each occurrence of limestone provides an opportunity for specific investigation, because the characteristics of stones in different localities vary. Knibbs13 has given an excellent discussion of available data on the theory of lime and magnesia burning. The thermal dissociation of calcium carbonate has been studied more recently by Johnstonr2 Smyth and Adams,3 Ralston et al.,4 Furnas,6 Potapenko,6 and Southard and Royster.7 As a result of these investigations the dissociation temperature at atmospheric pressure has been established as 894" to 898' C. The dissociation of dolomite and magnesite, although studied by several investigators,4,6,8 still requires clarification by additional data. The calcination of limestone was studied for a twofold purpose: (I) to extend our information on the mechanism of the lime-burning process and (2) to standardize the conditions for calcination of high-calcium and dolomitic limestones for subsequent hydration tests on the lime.

Jan 1, 1942