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By E. S. Moore

"The Centre of the silver-producing section of the Gowganda area lies about 55 miles northwest of Cobalt, and the village of Gowganda is 71 miles by road from New Liskeard. The geological similarities of the Gowganda and Cobalt areas led prospectors westward from the rich Cobalt field, first to Elk Lake and then on to Gowganda, where mineralization was found in 1907. A year later many showings were found, and rich hand-picked ore was shipped. Most of the ore has come, however, from two mines, both of which are still operating; the Miller Lake-O'Brien, which was purchased by Siscoe Metals of Ontario Ltd. in 1945, and the Castle-Trethewey. The annual production of these two mines runs over one and one-half million ounces of silver and considerable cobalt. The total production of the camp has reached about 32,000,000 ounces of silver and a large amount of cobalt, the total not recorded.General GeologyThe general geology of Gowganda is in many respects much like that of Cobalt. There are areas of Keewatin basic and acid Javas mixed with tuffs and basic intrusions. These rocks are deformed and partly altered to schists, and have been intruded by some Haileyburian basic and ultra-basic rocks and by Algoman granite. These were followed by a large number of porphyritic Matachewan quartz diabase dykes. After a period of extensive erosion the Huronian sediments were deposited on a pene-planed surface over all the older rocks; these sediments include large quantities of conglomerate (partly tillite), quartzite, and greywacke. The Keweenawan rocks include the Nipissing quartz diabase sill, later quartz diabase dykes, and one long olivine diabase dyke, the latest Precambrian rock. The area has been extensively glaciated.Structural FeaturesThere has been little folding in the area since the Algoman batholiths were intruded, and the Huronian sediments lie nearly flat, with dips of 10, 15, or rarely 25 degrees. The Matachewan dykes show a remarkably uniform, nearly north strike, indicative of east-west tension when they were intruded. On the other hand, the dykes later than the sill strike nearly east, tangentially to the northeasterly and northwesterly strikes of the Miller Lake basin."

Jan 1, 1949

By P. Ashtari

Influence of Sr and Mn single and combined additions on the modification of the Fe-containing intermetallic compounds and mechanical properties of Fe-rich AA319 aluminum alloys have been investigated, The microstructural features e,g, morphology of the Fe compounds and eutectic Si has been correlated to the mechanical properties, It was demonstrated that modification of the Fe compounds from the platelet ß-Al5FeSi to the Chinese script a-Al8Fe2Si compound improves the UTS and elongation of the alloys by 10.3% and 83.9%, respectively. Moreover, the simultaneous modification of the Fe compounds and eutectic Si increases the UTS and elongation of the alloys by 15,3% and 116,1%, respectively.

Jan 1, 2005

By Alan E. Renshaw

"This paper is a practical overview of ways to reduce cost in the design and operation of an Arctic mine. The economically important issues of the Arctic mine that will be addressed include: permafrost and the active zone in general terms; road building in and over permafrost; Arctic geotechnical mine design considerations; pit dewatering techniques in sub-zero temperatures; and blasting frozen materials with techniques to obtain optimal results. A final section on a few special topics conclude this paper.Although this paper primarily refers to near surface conditions more closely associated to an Arctic surface mine, many of the ideas and techniques contained in the paper also apply to the surface construction of an Arctic underground mine."

Jan 1, 1996

By F. W. Guernsey

Of all the elements, sulphur occupies a place by itself. It is mined in situ, in such quantities and of such purity that, as regards the tonnage produced, it is the first of any element on the list. Iron and coal the great tonnage producers, are combinations of elements, while sulphur is mined and marketed almost chemically pure. It is sold, in large quantities, commercially, calling for a purity of 99.5 per cent while for medicinal purposes, the Pharmacopoeia requires only 99 per cent. purity. It is a very common commodity, and like many common things is of extreme importance, in the progress of our civilization. The substance has been known from the earliest times, the word sulphur being derived from the Sanskrit Culvari", hence the Latin Sulphur. Commercially it is also called brimstone, this word being a derivative of the Anglo-Saxon Bryne Stane or burning stone. From our younger days, we have been more or less familiar with the mineral. On the spiritual side being threatened, if we did not behave ourselves, with an ultimate consumption in a lake of fire and brimstone, (which in moments of reflexion was not pleasant to contemplate) while our bodily ills were taken care of by inward applications as a spring medicine. In both instances, the effect required, was generally attained. Sulphur occurs in nature, both free and in the combined state, it being estimated that it forms, over one tenth of one per cent of the first ten miles of the earths surface. (I do not know who did the estimating and it is not guaranteed).

Jan 1, 1923

By J. F. Wright

During the last three years prospecting has been active in southeastern Manitoba and a number of interesting gold, nickel and copper deposits have been discovered within an area 90 miles north of the international boundary, and extending about 40 miles westerly from between mileage 60 and 110 on the Manitoba-Ontario boundary. As known at present, two-thirds of this area of 2,000 square miles is underlain by pre Cambrian granite and granite gneiss and is not likely to contain mineral deposits of economic importance. The remaining one-third is underlain by metamorphosed sediments and lavas (greenstones), penetrated by the granite and granite gneiss and, at various localities, cut by bosses, sills, or dykes of gabbro, diorite, granodiorite, and other types of intrusives. The nickel, copper, and gold mineralization accompanied or followed the intrusion of these different rock types. The gold deposits are limited in distribution, so far as known, to the northern part of this prospecting area and occur along Manigotagan and Wanipigow rivers. These deposits have recently been described in some detail, (3) and therefore only the copper and copper-nickel deposits of the southern part of this area, along Oiseau and Maskwa rivers, will be described in this paper.

Jan 1, 1925

By Lopatka. M. J.

This paper presents the results of 3 tons skid steer 6x6 wheel robot drive system field tests. The aim of the investigation was verification of assumed data for drivetrain diesain and forces identification in the drivetrain system during maneuvering and crossing obstacles. Robot has hydraulics drive system with motors in the wheels and hydraulic suspension system. The neded drive torque on wheels was determined by pressure measurnig on motors.

Aug 1, 2013

By P. Bramwell, R. Tremblay

"The Port Radium leaching plant of Eldorado Mining and Refining, Limited, produces 450 t./d. of sulphuric acid leach liquor containing l. 73 g. /I. U 308. After solvent extraction, the waste solution is discarded at 0.002 g./l. U30s for a recovery of 99.8 to 99.9 per cent. The solvent is acidified with weak sulphuric acid, loaded to 4.5 g./l. U80:1 in three-stage extraction, scrubbed with water, and stripped with soda-ash solution in single-stage stripping. Caustic removes the UaOs from the pregnant strip solution as a precipitate. The slurry is filtered, re-pulped with water, and re-filtered. The pressed precipitate at 81 to 82 per cent equivalent U30s is dried and packaged. The carbon-ate filtrate is cooled to remove sodium sulphate build-up and carbonated to convert excess caustic. Reagent consumptions are 4.1, 0.22, and 0.39 pounds per 1,000 gallons of pregnant solution for Diesel oil, amine, and alcohol, respectively. Caustic consumption averages 1.3 to 1.4 pounds per pound U3O8.Extraction and stripping is accomplished in sheet-iron mixer-settlers lined with Phenoline. Piping on both circuits is Schedule 80 polyvinyl chloride. Valves are straightway Buna N lined with American Hycar diaphagms. Extensive instrumentation ensures good metallurgy with a minimum of variations and labour. Mixing in a continuous organic medium and careful acidity control are required to minimize third-phase formations. Heating the precipitate slurry is conducive to good filtering in Perrin presses with neoprene-coated, rolled-steel sectors. Sodium sulphate is crystallized from carbonate filtrate solution by batchwise cooling to 54°F. with lake water."

Jan 1, 1959

By F W. Irwin

In recent years, a number of significant developments have occurred in the steel industry which are no-table and of general interest. This paper is confined to the steel-melting phase of the business. The development of high production rates on Stelco's Basic Open Hearth furnaces is chronologically summarized. Al-though various aspects of this subject have been presented previously, this paper summarizes the developments in high fuel rates, the usage of basic refractories, low and high oxygen rates and hearth maintenance. Background T HE interest which has been shown in steelmaking techniques in the past few years has been due, primarily, to the extremely high production rates obtained. Upon further study of the facilities and techniques employed to generate this steel at record rates, tonnage oxygen appears as the common factor. It can be stated that tonnage oxy-gen has revolutionized steelmaking techniques to a degree never before encountered. It was only about ten years ago that the use of large amounts of pure oxygen in a steelmaking

Jan 1, 1965

By J. J. Baz-Dresch

"The Cannon Mine, a joint venture between Asamera Minerals (the operator) and Breakwater Resources, is located in the centre of Washington state at the eastern base of the Cascade Mountains. The mine complex is located three blocks south of the city limits of Wenatchee, part of an urban area with a total population of 47 000. The closest residence is 350 feet from the mine portal.The B-Neath zone is a narrow, high-grade, downward extension of the southern tail of the mine's main ore body, the B-North zone. It also underlies the northernmost portion of the B-West zone (Fig . I) . The ore is usually reasonably competent but completely surrounded by very weak rock consisting of shear zone and unsilicified sandstones and siltstones.The zone has maximum dimensions of 420 ft in thickness, 500 ft in length , and 200 ft in width . The economic reserves extend from the 70-ft elevation (elevation above sea level) to the 630-ft elevation and consist of about 1.3 million tons of geologic reserves (proven and probable) at an average grade of 0.33 ounces per ton.Acquisition and ExplorationInitial DiscoveryThe initial discovery of the B-Neath zone was made by Tenneco Minerals during July through September, 1984. Their 22-hole surface drilling program consisted of 18 200 ft of drilling. Tenneco Minerals had acquired the 91/2 acre lease from United Mining Corporation.Asamera Minerals subsequently purchased Tenneco's lease in July, 1985; Tenneco retained a royalty position which was later purchased by Echo Bay Mining.Follow-up drilling by Asamera Minerals consisted of both surface and underground drilling. Eight surface holes (7200 ft) were drilled commencing in December, 1985. Following evaluation of the geologic data, an access drift was driven on strike along the top of the ore zone on the 500 level. Diamond drilling from this platform consisted of 17 200 ft in 79 holes."

Jan 1, 1990

By Mehmet F. Tauer, Pierre Trudel

"The metamorphosed mineralized Archean Bourlamaque batholith, dated at 2710 +-54 Ma, is a homogeneous body, composed mainly of quartz diorite; it is cut by late dioritic, mafic and aplitic dykes, and contains metasomatized ultramafic xenoliths. A geochemical investigation confirms the calc-alkaline affinity of the batholith, and the REE profiles are similar (Lal Yb = 3.9 to 8.1) to those of the intermediate to felsic metavolcanic rocks at Val d'Or into which the batholith was intruded and to those of the calc-alkaline members of the Blake River Group at Rouyn.Gold distribution within the batholith is heterogeneous and anomalous. Although the background Au content of the batholith is estimated to be 3.2 ppb Au by RNAA , the estimated median gold content of the batholith is 10 pp b (with P84 =32 and PI 6=3.1 ppb), much higher than that of ""normal"" granites (I to 5 ppb A u). The gold mineralization exhibits a close relationship with shear zones (e.g. Belmoral Mine) or with diorite dykes (e.g. Sullivan, Perron and Courvan mines).The following sequence of geological events is proposed: (I) pretectonic emplacement of the batholith, which is cogenetic with its volcanic host rocks; (2) regional metam orphism and deformation with localized shearing; and (3) hydrothermal alteration and quartz veining. We conclude that: (1) the Bourlamaque batholith is a gold-enriched intrusion, and (2) the determination of average gold content may be an effective method f or distinguishing ""sterile"" intrusions from those with potentials for gold mineralization.RESUMELe batholite archéen minéralise de Bourlamaque, daté de 2710+-54 Ma, est une intrusion homogène, constituée principalement de diorite quartzique, qui a été recoupée par des dykes tardifs de diorite, d'aplite et de composition mafique. Il contient aussi des enclaves de roches ultramafiques metasomatisees. L 'étude géochimique confirme le caractère calco-alcalin du bath olite et les profits des ETR sont semblables (La/ Yb=3.9 a8.1) a ceux des volcanites intermédiaires afe tsiques de la région de Val d'Or dans lesquelles le batholite fait intrusion et à ceux des unites calco-alcalines du Groupe de Blake Ri ver a Rouyn. La distribution de Au dans le batholite est à la fois anomale et hétérogène. Bien que le bruit de fond du batholite ait été estime à 3.2 ppb A u par AANR, sa médiane a été estimée a10 ppb Au (avec P84=32 et PI6= 3.1 ppb) , ce qui est nettement plus élevé que la valeur des roches granitoides ""normales"" donnée dans la littérature (1 a 5 ppb A u). Dans la batholite, la minéralisation aurifère est intimement associée aux zones de cisaillement (e.g. mine Belmoral) au aux dykes de diorite (e.g. mines Sullivan, Perron et Courvan).La séquence des évènements géologiques suivante est proposée: (1) emplacement pre-tectonique du batholite, lequel est cogenetique avec les roches volcaniques encaissantes; (2) deformation et metamorphisme regional avec des cisaillements tectoniques locaux; et (3) altération hydrothermale et développement des veines de quartz. Nous concluons que: (1) le batho lite de Bourlamaque est une intrusion enrichie en Au; (2) la determination de la teneur en Au peu être une méthode efficace pour distinguer les intrusions stériles de celles qui possèderaient un pot entiel pour des minéralisation s aurifères."

Jan 1, 1989

By Xiao min Zhou, Yan Xu, Hongzhen Liang, Xiaonan He

"With the increase of shaft excavation depth, the thickness of the shaft lining increases sharply. It is difficult to reduce thickness of lining effectively by improving high-strength concrete performance. The concept of the New Austrian Tunneling Method (NATM) is that surrounding rock plays a certain role in tunnel support. The solution should be to find the correct relationship between shaft lining thickness and rock strength, which is related with the interaction between the surrounding rock and concrete lining. The plane strain mechanics model is introduced to calculate lining thickness. Shaft lining design of Cixi Colliery in China is completed with the mechanics-based method proposed in this study. The lining design is verified through numerical simulation and field monitoring. The simulation results show that the maximum mises stress is located at the inner edge of the shaft lining. The increase of lining thickness cannot effectively reduce concrete grade. The monitoring results indicate that a lining design thickness of 900mm with C60 concrete, is safe and reliable in the shaft over 1000metres.This analytical design method can well be referenced in similar deep shaft projects.INTRODUCTION The New Austrian Tunneling Method (NATM), thought to have helped revolutionize the modern tunneling method, is the most extensive design philosophy and construction principle in today's tunnel engineering. It began to attract attention in the 1960s based on the work of Ladislaus von Rabcewicz, Leopold Müller, and Franz Pacher in Austria[1]. NATM was originally developed for tunneling in depth and in high situ-stress conditions in the Alps. The history of sequential excavation was reviewed, which highlights the progress of tunnel design and construction in Europe after NATM[2]. Structural conditions were introduced into the equilibrium of tunnels in NATM, and the additional force was estimated to stabilize the excavation of the tunnel[3].From the perspective of applied mechanics, there was no accuracy theory to explain the interaction between the tunnel structure and the surrounding ground. Numerical calculation is an effective means to study the basic mechanism of tunnel excavation[4].Based on two-dimensional modeling approaches in the past, such as NATM and other derivatives, a three-dimensional model was studied to"

Jan 1, 2019

By A. Y. Smith, R. J. Allan, E. H. W. Hornbrook, R. W. Boyle, W. Dyck

"HYDROGEOCHEMICAL METHODS in the Canadian Shield can be based on analyses of the following :(1) spring waters and their precipitates;(2) stream and river waters;(3) lake and muskeg waters;( 4) ground waters from drill holes, wells, faults, etc.;(5) waters issuing from diamond drill holes, faults, shear zones, etc. into mine workings and open pits; also analyses of precipitates associated With these waters.The first four can be utilized in both reconnaissance and detailed surveys. The last is suitable only for detailed work.For hydrogeochemical methods of prospecting to be effective, the following conditions must be present. 1. Natural waters must come into contact with mineral deposits and remain in contact with them long enough for the solution of detectible amounts of ore, gangue or indicator elements. 2. Dispersion patterns must be present in the hydrologic systems in order to trace the elements back to their source. These patterns may take the form of trains (e.g., increasing amounts of elements upstream toward t he source (s), Figure 1 ) or halos (e.g., increasing amounts of elements in bodies of water toward the source (s), F igures 2 and 3)."

Jan 1, 1971

By F. Vahdatikhaki

Simulation techniques have offered significant boosts toward a cost-and-time-optimized planning of construction projects by enabling project managers to effectively comprehend the behavior of projects. Using historic data from projects of like nature, simulation considers uncertainties involved in a project through accommodating the stochastic modeling parameters. However, the heavy reliance on the statistical data and not taking into account the context-specific features of the project cause the degradation in the realism and accuracy of the simulation models. Similarly, the extent to which a historic pattern could be retrofitted to new projects will decrease in line with the growing uniqueness of the projects and the novelty of construction methods. Furthermore, the existing real-time simulation frameworks are not capable of distinguishing the transient environmental changes, with minimal long-term impacts on the productivity, from the influential changes that will greatly impact an operation. In addition, existing simulation tools are devoid of location awareness, resulting in the inability to consider safety threats in their representation of the project. To address these issues, this research proposes a framework based on the integration of new tracking technologies used in Automated Machine Guidance (AMG) with simulation-driven 4D modeling methods. The proposed framework automates the adjustment of the simulation model based on the updated data from the site, and thus transforms simulation from a predictive tool used at the planning phase to a proactive monitoring platform usable throughout the planning and construction phases. A prototype is developed to test and demonstrate the effectiveness of the proposed approach.

Aug 1, 2013

The concept and practices of co-extraction of coal and methane have emerged in recent years to improve coal mining safety and productivity, utilise methane resources, and reduce fugitive emissions in environments that involve multiple coal seams with low gas permeability. The system of co-extraction integrates two previously separate operations of coal extraction and methane drainage. The coal mining operation reduces the coal seam gas pressure and creates strata fractures that enhance gas migration and capture from mine workings and surrounding coal seams. An effective methane drainage operation produces a consistent and quality clean energy product and, at the same time, reduces the methane concentration in underground workings and the methane content and pressure in the adjacent coal seams. This is a significant benefit in preventing gas explosions and outbursts, and promotes a safer and more productive coal mining environment. In addition, the co-extraction with enhanced utilisation of coal mine methane directly leads to a reduction in greenhouse gas emissions. Presented in this paper are key results and outcomes of a major Asia Pacific Partnership project carried out from 2008?2012 by the Commonwealth Scientific and Industrial Research Organisation in collaboration with Huainan Mining Industry (Group) Co. Ltd., to develop and demonstrate advanced technologies at Pansan mine, Huainan, that promote the concept and practices of co-extraction of coal and methane. A comprehensive approach was adopted to assess fundamental strata and coal seam methane conditions during mining, and optimise mining sequences and coal mine methane capture systems. The project has not only demonstrated a practical approach and procedures of advanced co-extraction of coal and methane systems but also delivered significant benefits and outcomes in improved mining safety and efficiency, increased methane capture and utilisation, and reduced fugitive methane emissions at the Pansan mine. The total mine gas drained increased from 25.36 Mm3 in 2007 to 47.0 Mm3 in 2011, and the mine gas utilisation increased from 4.94 Mm3 in 2007 to 21.15 Mm3 in 2011. The improved methane capture resulted in reduced coal and gas outburst risks and methane concentration levels at the mine workings, provided a safe working environment for coal production, boosted the mining efficiency, and eliminated methane related incidents over the last few years at Pansan mine.

Aug 1, 2013

By A. Motamedi

Indoor localization has gained importance as it has the potential to improve various processes related to the lifecycle management of facilities and to deliver personalized and location-based services. Radio Frequency Identification (RFID) based systems, on the other hand, have been widely used in different applications in construction and maintenance. This paper investigates the usage of RFID technology for indoor localization of RFID equipped movable assets during the operation phase of facilities. The location-related data on RFID tags attached to fixed assets are extracted from a Building Information Model (BIM) and can provide context-aware information inside the building which can improve Facilities Management (FM) processes. The paper proposes a new approach to use received signals from available reference tags in the building attached to fixed assets to locate movable assets. The approach uses signal pattern matching and clustering algorithms for localization. As a result, a user equipped with an RFID reader is able to estimate the location of target assets, without having access to any Real- Time Location System (RTLS) infrastructure. A case study is performed to demonstrate the feasibility of proposed methods.

Aug 1, 2013

By E. Onal

Mining operators are faced with complex information delivered by technology-centric rather than user-centric systems. The ability to achieve high situation awareness (SA) in the face of this data overload is a key challenge for effective decision making and information exploitation. Incidents that result in loss of revenue and even life, and compromise safety that are attributed to human error are often the result of system designs that overload human cognitive capabilities. This paper focuses on defining SA as it relates to mining operations and presents methods for improving SA through a scientific approach for electric shovel operator user interface development.

Aug 1, 2013

By M. E. Wilson

"The property of McWatters Gold Mines, Limited, is in the east-central part of Rouyn township and about 6 miles east-southeast of the town of Rouyn. It includes 35 claims, the group of 5, staked originally, and 30 claims acquired in later years. The Rouyn-Val d'Or road and the Noranda Senneterre branch of the Canadian National railway both pass within a few hundred feet of the mine.The group of claims in which the mine occurs was first staked in 1922, but gold was not discovered until August 1932 when a schistose zone including veins of quartz carrying considerable free gold was laid bare in a stripped area in the northeastern part of claim R.11604. Diamond drilling undertaken in 1932, and continued into 1933, shouwd that the gold extended for at least 1,000 feet along the strike. A 3-compartment shaft was sunk to 418 feet in 1933. A mill having a capacity of 50 tons a day was constructed in 1934, and enlarged to 150 tons in 1935. Production began in 1934 and continued without interruption to June 1944. Except for a few diamond drill holes, there have been no operations on the property since that time. The maximum depth of the mine workings is 1,50) feet. A total of 368,013 tons of ore having a value of $3,946,752 and an average grade of $11.04 was mined during the years of operation.GEOLOGYThe ore mined from the property occurred within the south limb of an eastward plunging syncline of volcanics and sediments cut off on the north by the Cadillac-Bouzan Lake fault. Because the rock formations within the syncline have been severed from those outside with which they were originally continuous, their correlation is based almost wholly on lithological similarity. They include an irregular middle zone of conglomerate and greywacke underlain by north and south bands of andesite agglomerate and andesite tuff, in which lenticular bands of pillowed andesite are included."

Jan 1, 1954

By Gurinder Kaur

Selenium (Se) based materials find wide applications in rectifiers, solar cells, photographic exposure meters, data storage devices, xerography and anticancer agents. They are also used in the glass industry to eliminate bubbles and remove undesirable tints produced by iron. In addition, Se is highly reactive towards a wealth of chemicals that can be potentially exploited to convert Se into other functional materials such as CdSe, ZnSe, Ag2Se. Here, we report a review of structural investigations of Se based materials in glassy and nanostructured forms. Glasses having varying amounts of Se and Tellurium (Te) were doped with group IV and V elements such as antimony and tin. Structural changes accompanying the composition variation were characterized with x-ray photoelectron spectroscopy, differential scanning calorimetry and x-ray absorption near edge spectroscopy. At the same time Se-Te nanoalloys were synthesized in aqueous micellar phase using Na2SeO3/Na2TeO3 as the Se/Te source. Morphology change from nanoparticles to nanoribbons was investigated using Scanning and Transmission Electron Microscopy (SEM/TEM) techniques. Structural investigations were also done for well defined morphologies of Se based nano-biomaterials obtained in the presence of water soluble protein bovine serum albumin (BSA).

Aug 1, 2013

By Javier Linares García

At then end of this year will be 10 years of producing concentrate for Antamina. This is a summary of what occurred over the last decade to increase production and tonnage above the design tonnage of 70,000 tonnes per day, up to an average of 100,018 tonnes per day in 2010, an increase in production of 42.9%. Equipment currently in use is the originally installed equipment, signifying a meaningful increase in capacity without capital. In this paper, the different phases of improvements and the realization of their impacts in chronological order will be outlined. Figure 1 below shows the average daily tonnage processed each year (tonnage throughput each year/calendar days), as well as the percentage increase over the tonnage of design.

Jan 1, 2012

By Norman Orr, J. W. Gregg, Jack Wahl

The Pembina Cardium pool is a low permeability, stratified, solution-gas drive reservoir. Water-flooding has proven to be an effective means of pressure maintenance for all areas of the pool in which an economic rate of water injection can be maintained. The majority of water injection wells in the pool are converted oil well~ with capacities greater than 100 millidarcy-feet. If the average injection rate per unit of capacity can be in-creased the lower capacity areas of the pool can be economically flooded. Theory, laboratory work, and two . early miscible-flooding projects with-in the pool suggested that average water injection rates for converted wells could be increased two to three-fold by the initial injection of natural gas liquids and natural gas. How-ever, these two early projects received volumes of natural gas liquid!:' and high-pressure natural gas which would be economically prohibitive for routine stimulation. Area D, one of the Five-

Jan 1, 1962