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By A. M. Bryukhanov, A. G. Mnukhin

The report states accident rates for gassy/dusty coal mines represented as an ergatic system "man – machine - environment" with further analysis by the method of conditional probabilities. A coal mine has been analyzed with allowance for the attending personnel, equipment and environment as a sequence of events and states. Probabilities of operational states have been determined and prediction of mine behavior has been made on the basis of investigation findings for equipment and the personnel states, and analysis of the environment (i.e. mine and mining conditions). Utilization of expert estimation methods has been considered for determining major operational parameters of gassy/dusty mines. The importance of standardized values of permissible occupational risks (permissible probability of accident, PA) is demonstrated. It is also stated that a procedure is essential to determine these values, involving regular check-ups of the integral safety criterion at all mines and further development of customized recommendations for individual mines on efficient improvement of accident situations. Methodology to determine the assessment criteria has been developed and scientifically substantiated for permissible accident rates in hazardous industries.

Jan 1, 2003

The Bureau of Mines evaluated short-delay coal mine detonators manu-factured by three domestic companies for electrostatic sensitivity, strength, and no-fire current level. Electrostatic sensitivity was studied in pin-to-pin and pin-to-case modes employing lO-kV potential. Strength of detonation was measured in the Bureau's underwater test fa-cility. No-fire current was measured using a constant-current power supply unit. Test procedures and experimental data are included.

Jan 1, 1985

By Hugh McMillan

To protect the water supply for the Metropolitan Chicago area, the Illinois legislature, in 1889, created the Metropolitan Sanitary District of Greater Chicago. To insure the quality of the water supply, the Sanitary District collected and diverted the wastes of 750,000 people away from Lake Michigan. Today, the Sanitary District collects and treats the wastes from a domestic population of 5 ¼ million people and an industrial waste load equivalent to 4 ¼ million people. The District serves Chicago and 120 other cities and suburbs in an 858 square mile area. An average of 1300 million gallons of wastewater is treated each day, producing as a by- product about 700 dry tons of solids which contains more than $10,000 worth of plant nutrients when equated to the value of commercial fertilizer purchased in the retail market. The Sanitary District considered several alternatives to past methods for disposing of these solids, and chose land application as a technique to utilize the solids produced by the wastewater treatment process in a beneficial manner.

Jan 1, 1973

The mining industry is the largest source of foreign income for South Africa. It is also the main source of employment in the country and, as an industry; it is also one of the largest. Due to the labour-intensive nature of the industry, labour costs in South African mines make up nearly 50 per cent of the total mine cost. It is thus imperative to have optimum labour planning and labour management systems in place.The focus of this study was to investigate current underground labour-planning models. It is shown that there are serious limitations. The range between an oversupply and undersupply of labour can be as high as ten per cent. A new system was therefore developed to ensure a constant labour demand and supply on a daily basis. One of the main objectives was to determine the existing labour supply range and thus the requirements to fill the undersupply. For this purpose, a specific methodology was designed to capture and process all the relevant information. Mine personnel was involved throughout the entire process to ensure ownership of the new model. This buy-in was achieved through planning workshops, interactive presentations and discussions. The improved frequency of daily blasts validated the new system by providing the correct amount and mix of the labour force. The new labour-planning model was then extended to optimise revenue. Implementation on a mine resulted in increased income of R95 million.

Dec 6, 2010

By W. J. Asselstine

Introduction This paper is prepared from data gathered for a similar paper to be submitted to the United States Bureau of Mines, for publication as one of their information circulars. It covers the history and development of the present milling practice at Premier. The authors wish to acknowledge the assistance and suggestions given during the preparation of this paper by D. L. Pitt, Manager of the Premier Gold Mining Company, Limited; also their indebtedness to various members of the Engineering Staff and of the Accounting Department who have assisted materially in gathering the data used. Location The Premier mine and mill are situated in northern British Columbia, approximately fifteen miles north of the head of Portland canal, in the Salmon River section, about half a mile east of the Alaska-British Columbia boundary line where it crosses die Salmon river. The mill is located on a rather steep hillside on the horizon of the main haulage level of the mine, and is within a hundred feet of the mouth of the tunnel. Both the mine and mill are connected with tidewater at Stewart, B.C., by an aerial tramway (1) eleven and one-half miles in length, which delivers both ore and concentrate to the bunkers at the dock for shipment to the smelters. All mine and mill supplies are transported from Stewart dock to Premier over this tramway, except heavy machinery. Heavy pieces have to be hauled either by truck in summer or sleighs in winter over a good road which runs from Stewart dock to Premier.

Jan 1, 1933

By P. S. Jacobsen

In 1960 over 93 percent of the coal cleaned mechanically in the United States was cleaned in processes that utilized water or dense-medium suspensions of fine solids in water. Thus, in the process of removing deleterious ash-forming and sulfur-bearing minerals, another deleterious substance--water-- is added to the coal. The subsequent removal of the water from the coal, and the concomitant recovery of the coal from the water, is not troublesome in the sizes coarser than 1/4-inch. In the finer sizes, however, it is a difficult procedure that often costs more than the original washing operation. Because of the importance of liquid-solids separation in coal preparation, the Bureau of Mines has a continuing program of research in this field. The objective is to make available information on the performance characteristics of various types of equipment available for liquid-solids separations, thus promoting the wise selection of equipment for specific applications, and, thereby, more effective processing of coal. Results of work on flocculation as an aid to filtration5 and the sieve bend screen6 have been published. The present investigation of the screw-type classifier operating in combination with the cyclone was undertaken primarily because such classifiers are comparatively new to coal preparation and information on their performance is not available. The cyclone has become well-known since its introduction in this country by the Bureau of Mines in 1948.7 Use of the cyclone in conjunction with the screw-type classifier represents an attempt to provide the maximum recovery of solids at minimum moisture content.

Jan 1, 1962

By H. R. Shell, John L. Miller, M. V. Denny

In the mica research program conducted by the Bureau of Mines at Norris , Tenn . , many micas other than silicon fluorphlogopite have been synthesized . It has been well established since the initiation of the program that synthetic micas are important materials useful for their superior or unique properties as well as substitutes for natural micas . The possibility of controlling the physical properties of synthetic mica by isomorphic substitution of other ions in the fluorphlogopite lattice further emphasizes the importance of these materials . Accurate measurement and reporting of their properties constitute an essential part of the research program . The study of germanium fluorphlogopite is in keeping with the requirements of a comprehensive study on isomorphic substitution , specifically to identify precisely the material -- chemically , structurally , and optically . The X- ray measurements , including indexed powder and single crystal data , with a description of the methods used to obtain these data , are provided . 5 Earlier work on germanium mica by R. A. Hatch et al . (5) gave an estimate of the cell parameters from X - ray powder data , but no attempt was made to index the diffraction pattern or to determine the space group symmetry . Later work by E. A. Schatz and J. C. Withers (9) listed X- ray and optical measurements , but no attempt was made to index the mica or determine its symmetry . Roth (7) found that germanium dioxide having the a - quartz structure , when heated with equimolar percentages of MgO , CaO , Sr0 , or Ba0 at 1,235 ° C , formed ABO3 -type compounds , e.g. MgGe03 isostructural with enstatite (MgSiO3 ) . Geo₂ also has a rutile - type polymorph with Ge ++ ions in octahedral coordination . Germanium was substituted for silicon in the serpentine structure by Roy and Roy (8 ) using hydrothermal techniques . These authors wrote as follows : "The substitution of Ge + for Si + yielded a magnesia - germania serpentine , formed easily in euhedral hexagonal plates which in some instances were visible in the light microscope . Electron micrographs and the sharp X - ray diffraction patterns confirm a plate - like rather than tubular habit . " It has been shown in this investigation that substitution of germanium for silicon in the mica structure is readily accomplished without radically changing the characteristics of the mica . Substitutions in the mica structure take place in three locations : Tetrahedral , octahedral , and interlayer positions . The tetrahedral positions are normally occupied by Sit or by a combination of Sit with Al +3 the most common combination being 2A1 +3 and 6Si +4 · , The octahedral position , which has six - fold coordination in phlogopite , contains a larger cation such as magnesium . In muscovite it contains only 2A1 ions ; therefore , this mica is considered a dioctahedral mica , whereas phlogopite is considered trioctahedral . +3 The interlayer position has twelve - fold coordination with six oxygen ions from each of two adjacent tetrahedral silica layers . This is the cleavage plane of the mica and commonly contains the largest cation in the mica structure (e.g. potassium) .

Jan 1, 1964

By Junhong Noh, Kug Sun Hong, Jung-Kun Lee, Bo Ding

"The photocatalytic splitting of water into H2 and O2 by oxide nanoparticles has received much attention. However, the full potential of photo-catalysts for efficient hydrogen generation out of water has not been fully realized yet due to unresolved limitations including the low electrical conductivity and ineffective carrier extraction. Here, we report composite oxide materials consisting of 1-dimensional (1-D) transparent conducting oxide (TCO) core and TiO2 shell. Highly conductive ITO nanowires were grown on a flexible SUS mesh as a core component. The photoelectrodes consisting of these 1-D nanocomposites have increased carrier mobility due to the TCO core, while the TiO2 shell provides the photocatalytic functionalities. In addition, the built-in-potential at the interface between TCO core and the TiO2 shell improves the collection of charge carriers from TiO2 to TCO. These factors altogether contribute to increasing the photocurrent of the device under light.I. IntroductionPhotocatalytic behavior of semicondcutors has been extensively explored since it was discovered in TiO2 in 197Os. When TiO2 is exposed to UV light, the light is absorbed and electron/hole pairs are generated in the conduction and valeence bands. Holes in valence band will oxide/mineralize pollutant target directly or indirectly (via mediator hydroxyl radical). If the adsorbed A is O 2, O 2 will react with electron from conduction band to generate hydroxyl radical as described in the second set ofreactions. The photocatalytic reaction is schematically explained in Figure 1.Photoelectrochemical (PEC) cells using the photocatalytic reaction have attracted emerging interest as a potential route to convert solar radiation into useful forms of energy by reaction such as water splitting to generate hydrogen1 or the reduction of carbon dioxide.2 Another application ofphotocatalysis is water splitting and CO2 reduction, both of which utilize the electrons that are optically excited to the conduction band. 3•4 For this purpose, the conduction level of the semiconductor should be higher than hydrogen production level (EHZ1HZO) while the valence band should be lower than water oxidation level (Eo21112O). Electrons and holes will be generated on the semiconductor site, and holes generate O 2 at semiconductor site, while electrons will migrate to counter electrode to execute reduction forming H2. In addition to that, materials should be chemically stable to resist photocorrosion and have long lifetime of electron/hole pairs. TiO2 is a suitable material from the viewpoint of band arrangement and chemical stability requirement"

Jan 1, 2012

By C. L. Kosmoski

In recent years, coal mining safety has attained national attention due to several highly publicized disasters. Despite these threats to worker safety and health, the U.S. relies on the mining of coal to meet its need for electrical power, with 42% of electricity in the U.S. generated through the burning of coal (U.S. Energy Information Administration, 2012b; United Mine Workers of America, n.d.). Furthermore, the production of coal continues to increase and reach record levels every year (National Mining Association, 2012; U.S. Energy Information Administration, 2012a). For this reason, the coal mining industry must continue to find ways to protect its workers while maintaining productivity. One potential approach to protecting workers while maintaining productivity is through improving the safety culture at coal mines. In order to achieve this culture, operators, employees, the inspectorate, etc. must share a fundamental commitment to safety as a value. This type of culture is known in other industries as a ?safety culture,? and can be defined as the characteristics of the work environment (such as the norms, rules, and common understandings) that influence facility personnel?s perceptions of the importance that the organization places on safety. Fundamental to improving safety culture within an organization is understanding the existing safety culture; improvements cannot be made without first elucidating areas that require improvement. This manuscript details the process undertaken by researchers at the National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) to assess the safety culture at five underground coal mines across the United States. The purpose of this manuscript is to present the aggregated results from those five safety culture assessments conducted at underground coal mines. Additionally, some general recommendations for areas where coal mines might focus their attention as part of their attempts to improve safety culture are offered.

Feb 23, 2014

By Brotzmann K, Turner RE, Philp DK, Rusden RC

New approaches in the last decade have led to the supplemental use of raw coal as a direct energy source in several iron and steelmaking processes. The dependence on more expensive coke and electricity is being progressively reduced. The Technology Venture of Klockner Werke and CRA has pionered several of these developments and is pushing ahead to processes for scrap melting and direct smel- ting of iron where coal is the ONLY energy source. Such complex developments depend strong- ly on the experience gained in the simpler but related processes for coal use already in operation. The longer term implications of a successful coal-based direct smelting process for the world steel industry are substantial.

Jan 1, 1986

By C. Barnett

"The mill at Noranda Mines Limited, Geco Division in Manitouwadge, Ontario went into production in 1957 treating 3,500 tons per day of copper, zinc, silver, lead ore. It was not until 1964, however, that the zinc concentrate drying plant was constructed. In 1970, milling capacity was increased from 4,000 to 5,000 tons per day. The zinc content of the ore is quite variable so that the tonnage of zinc concentrate dried varies from 200 to 650 tons per day.The drying plant was designed to dry 25 tons of zinc concentrate, dry basis, per hour from an initial moisture of 8.5% to a final moisture of 2%. Major components were selected so that capacity could be increased to 35 tons per hour with minor modifications.The rotary dryer is a Hardinge type ""XH-12"" with a diameter of 80"" and a length of 50 feet. The all welded construction shell is 1/2 inch thick mild steel plate with 3/4"" thick reinforcing bands under the tires arranged for operation at a slope of 1/2 inch to the foot. The 3/8"" x 12"" radial flights are welded to the shell. There are no flights in the last ten feet of the shell in order to reduce dusting. This unit is driven by a 50 HP motor through a Hamilton type CD250 double reduction helical gear speed reducer. The shell speed is 5.8 RPM.The standard Peabody horizontal air heater has a rated capacity of 10,000,000 B.T.U. 's/Hr. The combustion chamber is lined with high temperature refractory brick and is air cooled. The conical outlet section of the air heater is lined with insulating fire-brick. The burner is a type AT wide range mechanical atomizer fired by a type ""CR"" gas-electric ignitor.The Bunker ""C"" fuel is supplied by a Compower duplex pumping, heating and straining unit, including tank hotwell, Powertronic oil line heating system with a 550/24 volt transformer."

Jan 1, 1972

By David B. Brooks

I gratefully acknowledge the help of a number of American and Canadian geologists, in both federal surveys and in private firms, who took the time to discuss this problem with me. Hans Landsberg and Bruce Netschert also followed the study with interest and encouragement. In their 1961 monograph, THE FUTURE SUPPLY OF THE MAJOR METALS, Bruce Netschert and Hans Landsberg noted that identified potential resources (that is, known but submarginal resources) of lead and zinc were much lower relative to reserves (that is, known and supermarginal resources) than was the same ratio for other metals.1/ Put another way, it seemed that for such metals as iron, manganese, copper, and aluminum, slightly more favorable economic conditions or modest advances in technology would greatly increase reserves by permitting the exploitation of vest quantities of leaner or deeper or otherwise less valuable mineral deposits. But for lead and zinc, Netschert and Landsberg concluded that either: "(1) there is relatively little material below present cutoff grades; [or] (2) such material exists, but for some reason there are no data.? 2/ This situation, which they called "the lead-zinc anomaly" has been subsequently discussed by other authors. The purpose of this paper is to carry the discussion further by examining the evidence in favor of (1) and (2) and by advancing a third alternative.

Jan 1, 1967

By W. Mueller, M. Rocheleau, E. Dimroth

The paleogeographic evolution of the Abitibi Belt is subdivided into three phases, namely: 1) a phase of the growth of a submarine volcanic chain, 2) a phase of the emergence and growth of volcanic islands and 3) a phase of uplif t and erosion of volcanic islands. Isostatic calculations suggest that the volcanic sequence in the south of the Abitibi Belt rests on oceanic basement or on the mantle; the volcanic sequence in the north of the belt rests on about 13-14 km of tonalitic basement. 10-15 km of plutonic material accreted to the volcanic islands during paleogeographic phases 1 and 2, and caused the uplif t during paleogeographic phase 3.

Jan 1, 1984

By James J. Meadows, Jason D. Pampena, Emanuele G. Cauda, Lauren G. Chubb

Exposure to respirable crystalline silica (RCS) can cause serious and irreparable negative health effects, including silicosis and lung cancer. Workers in coal mines have the potential of being exposed to RCS found in dust generated by various mining processes. The silica content of respirable dust in one single mine can vary substantially over both time and location. The current monitoring approach for RCS relies on the use of traditional air sampling followed by laboratory analysis. Results generated using this approach are generally not available for several days to several weeks after sampling, and this delay prevents timely and effective intervention if needed. An alternate analytical method is needed to reduce the time required to quantify the RCS exposure of mine workers. The National Institute for Occupational Safety and Health (NIOSH) has developed a new method using commercially available portable infrared spectrometers for measuring RCS at the end of the sampling shift. This paper will describe the application of the new field-based RCS analytical process for coal mines, including the use of the new method with the existing Coal Mine Dust Personal Sampler Unit. In a case study conducted by NIOSH with a coal mine operator in West Virginia, field-based RCS analysis was completed at a mine site to evaluate the new technique. The RCS analysis results obtained by the field-based method in this case study showed sufficiently strong correlation with results obtained by the MSHA standard laboratory analysis method to allow the mine operator to use the field-based method for evaluating process improvements.

By Daniel J. Turk, William R. Banning, John Paterson, Thomas J. Weitz, Michael L. Clark

Introduction Pegasus Gold's Montana Tunnels mine is a large surface gold, silver, lead, and zinc mine located 37 km (23 miles) south of Helena in southwestern Montana. Milling operations commenced in late March 1987. The concentrator achieved full production in May that year after undergo¬ing several modifications and improvements. Production for 1988 is projected to be 2.48 t ,80,000 oz) of gold, 34.2 t (1.1 million oz) of silver, along with 8.5 kt (9400 st) of lead, and 22.6 kt (25,000 st) of zinc from lead and zinc concentrates. Mill throughput currently averages 11.7 kt/d (12,900 stpd), compared to the origi¬nally designed capacity of 11.3 kt/d (12,500 stpd). Cash production costs, net of bypro¬duct revenues for the third quarter 1988, were below $3.20/g ($100 per oz). The introduction of ore to the concen¬trator marked the culmination of 12 years ex¬ploration, evaluation, and development. Initial milling operations encountered diffi¬culties with the circuit as designed. As a result, several modifications and improve¬ments were made to the plant. This article is intended to assist other companies developing projects of this type and complexity. It discusses the mine's de¬velopment from feasibility and construction through start-up. The operation, as it exists today, is reviewed including the modifica¬tions and improvements made since start-up. History The mine is situated in Jefferson County, MT within the historic Corbin-Wickes min¬ing district. Underground mining began in 1864 and flourished until the early 1900s. Between 1864 and 1900 the vein deposits in the district produced about $41 million dol¬lars worth of lead and silver ores containing subordinate amounts of zinc, copper, and gold. At various times, three smelters were operated in the area.

Jan 1, 1989

By Shahriar Vahdani, Andy Herlache, Andrew Bro, Wei-Yu Chen

"The Presidio Parkway Project will reconstruct approximately 1.6 miles of highway, including seven bridges, three cut-and-cover tunnels, and an undercrossing connecting the Golden Gate Bridge to the City of San Francisco, California. The project site is approximately 5.6 miles from the San Andreas Fault, which is capable of producing magnitude 8 earthquakes. Seismic hazards include strong ground shaking, soil liquefaction, ground settlement, and lateral spreading. At the Tennessee Hollow bridge section up to 30 feet of loose sands and soft clays are present. Concerns are raised that standalone drilled piers will experience excessive lateral soil loads from liquefaction-induced lateral spreading pressure resulting in excessive pier head displacement of up to 8 inches. Ground improvement by Cement Deep Soil Mixing (CDSM) is proposed to provide additional foundation stiffness. This paper presents the methodology to: 1) assess the effectiveness of the ground improvement in resisting lateral spreading, and 2) optimize ground improvement design at individual bridge bents based on local site condition. A series of 3-D numerical analyses are conducted and the results show that drilled piers with CDSM ground improvement are capable of withstanding seismic demands from lateral spreading and the lateral pier head displacement is reduced to less than 2 inches. The adopted analytical approach is efficient at modifying design for individual bents and can be considered for future pier foundation design in seismically active areas. IntroductionThe Tennessee Hollow bridge section (Low Viaduct) is an integral component of the Presidio Parkway project which will replace the existing facility with a new multi-lane roadway between the Golden Gate Bridge and the City of San Francisco. As shown on Figure 1, the project site is located about 5.6 miles east of the San Andreas Fault and 12.5 miles west of the Hayward Fault. The Low Viaduct will span over a future wetland habitat subject to tidal fluctuations and potential scouring."

Jan 1, 2014

By T. G. Hawkins, T. M. Naciuk

"The Katie Cu-Au deposit is situated in southeastern British Columbia, 425 km east of Vancouver. The deposit is a member of the alkaline group of porphyry Cu-Au deposits associated with potassically and propylitically altered andesitic volcanic rocks.The Katie porphyry system occurs in mafic to intermediate alkaline volcanic rocks of the Lower Jurassic Elise Formation of the Ross/and Group. Host metavolcanic rocks include andesitic to basaltic flows, flow breccia, massive fine tuff and crystal tuff Gabbroic intrusions alternate with the volcanic rocks in drill core. The lack of chilled margins and shear contacts, as well as their similar composition to the volcanic rocks, suggest that the gabbro was synvolcanic.Alteration exhibits a zonal pattern spatially related to zoned porphyry-style mineralization. Propylitic alteration is common and assemblages consist of epidote, chlorite, sericite and calcite. Potassic alteration zones are accompanied by elevated copper-gold grades and are composed of K-feldspar, plagioclase, quartz, biotite and chlorite. Narrow drillhole intervals of secondary magnetite, generally less than 2 m across, occur above the potassic alteration zones. A thick oxidized cap lies above the mineralized zones, although only local supergene enrichment has been identified. The lack of supergene enrichment is perhaps due to intense near-surface fracturing and leaching from a high energy groundwater environment.Sulphide mineralization consists mainly of pyrite within the propylitic halo, and pyrite and chalcopyrite with trace pyrrhotite, sphalerite, tetrahedrite, bornite and molybdenite within the potassic alteration core. Malachite, azurite and traces of chalcocite occur within the oxidized cap.Discovery and exploration techniques have included airborne geophysics, regional stream sediment sampling, prospecting, geological mapping, ground geophysical surveys, soil sampling surveys, and diamond drilling. Two primary targets of porphyry copper-gold mineralization have been identified by exploration. The Main zone strikes northwest, has an apparent true thickness ranging from 70 m to 135 m, and is a minimum of 500 m in length. The 17 zone strikes northwest, has an apparent true thickness of 90 m, and is a minimum of 300 m in length. The two zones are defined by grades that generally exceed 0.2% Cu and 0.25 g/t Au. Both zones are open along strike and to depth."

Jan 1, 1995

By George Watkin Evans

The United States Geological Survey has estimated 1 that the State of Washington contains 11,412,000,000 tons of bituminous coal and 52,442,000,000 tons of subbituminous coal, in beds more than 14 inches thick. As the present rate of production is about 4,000,000 tons a year, Washington apparently contains coal enough to supply Pacific coast markets for many years. The character of the coal beds of Washington renders the production of clean coal very difficult, and a considerable proportion of the output is washed before it is marketed. In 1915 Washington ranked fifth among the States in the amount of coal washed, though only twentieth in total output. In that year 37.9 per cent of the coal produced in the State was treated in surface cleaning plants.

Jan 1, 1924

By Clayton A. Landsidle

There has been little change in timbering methods in anthracite mines for 75 years, and technical information on strata control is almost wholly lacking. In order to assist the industry to establish technical data, the Bureau of Mines and a Northern field operator are cooperating in underground experiments, the first phase of which has been to investigate pneumatic packing. The four principal methods of packing in mining are hydraulic, pneumatic, mechanical, and hand. The hydraulic pa caring system is believed to have originated at Shenanodah, Pa., in 1864,4/ to prevent destruction of a church by surface subsidence after underground coal mining. This method was used again in 1884 to arrest an underground fire at Buck Ridge colliery, near Shamokin, Pa. In 1901 hydraulic packing was introduced to Europe in Upper Silesia, where it gained in popularity owing to the availability of large quantities of sand suitable for flushing .5/ Hydraulic packing has a number of disadvantages. Chief among these are the softening effect of large quantities of water on the mine floor conducive to heaving action; drainage and punning costs; and the inability to fill roof cavities completely in flat beds.

Jan 1, 1953

By Walter E. Hopper

(Wilkes-Barre Meeting, June, 1911.) I. LOCATION AND EXTENT. THE Caddo oil-field, shown in Fig. 1, is located in Caddo parish, northwestern Louisiana. The known producing territory of oil is covered by townships 19 N, 20 N, 21 N, 22 N, and ranges 15 and 16 W., shown in Fig. 2. The center of the field may be taken as Oil City, 24 miles north of Shreveport, on the Kansas City Southern railway. Shreveport is the second largest city in the State, and is the connecting point of five rail-road-lines. Drilling at the present time, however, is going on all over northern Louisiana, especially in Caddo and the neighboring parishes. II. HISTORY AND DEVELOPMENT. Natural gas escaping at the surface is found at numerous places in northwestern Louisiana. At Shreveport, the plant of the Shreveport Ice & Refrigerating Co. has been lighted by natural gas for 20 years. The well was drilled for water, but was abandoned on account of the gas. A test well, put down in 1905 near the western limits of Shreveport, was driven to 1,650 ft., and encountered indications of gas and oil at various depths, but did not succeed in finding enough to be profitable. Attention was first attracted to the Caddo field in 1895 by indications in water-wells from 40 to 60 ft. deep, in which the pressure of natural gas was noticeable. This indication of gas in a shallow well led to the drilling of the first well in the Caddo field, the old Savage Brothers & Morricell, or the Caddo Lake Oil and Pipe Line No. 1. The rig for this well was erected in May, 1904, and drilling began in June, 1904. The well was bailed Mar. 23, 1905, with a small amount of oil. It was deepened July, 1905, and converted into a "gasser " Jan. 3, 1906. It was abandoned January, 1907. In consequence of the finding of oil in the Savage well, drilling-operations were pushed with energy; and in April, 1905, four wells were drilling. Great trouble was experienced with

Apr 1, 1911