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By Simon C. Dominy, Ian M. Platten

"Abstract - Gold-bearing quartz reefs commonly show extremely erratic and unpredictable grade variation, although gross geological continuity may be good. This type of variation is often described as being nuggety or having a high nugget effect and can be measured quantitatively using the semivariogram. Understanding of geological features such as reef texture and structure will provide improved models for the interpretation of assay data, drill core descriptions, etc. In this paper, a case study from the quartz-hosted gold occurrences in the Gwynfynydd mine, United Kingdom, is described. The work provides a starting point for models of lateral variation and demonstrates the types of structural and textural features that may be sought to give clues to the prediction of gold distribution in similar deposits. Gold deposition at Gwynfynydd is primarily associated with the reef footwall. The host veins form a discrete group of structures that may have been emplaced early in the sequence of quartz veins forming the reef. This potentially exposes them to a maximum number of dissection events during repeat dilations of the lode. Gold was deposited in the local porosity at extreme concentrations, equivalent to kg/t grades, when the host fissure had become filled with a porous framework of crystalline quartz and sulfides. Distribution of porosity varied laterally along the vein as the result of the formation of clump-like growths of minerals from the vein walls. The growth style is relevant to the distribution of gold although it may not be relevant to the occurrence of gold in a particular vein. The preservation of pores with some connectivity late in the vein fill sequence may be important in permitting continued but slow fluid flows. This facilitates effective fluid reaction with wall rock-derived methane, thus changing the relative rates of gold and quartz deposition in favor of gold. The textural studies explain the first-order control of nugget distribution at Gwynfynydd but do not allow for prediction and optimization of the resource estimation process. This is principally because of the very low geological continuity and poor predictability of the high-grade pockets. Nonetheless, the work does provide a clear geological explanation for the erratic nature of the gold. It indicates textures and structures that can be used to determine geological continuity of the goldbearing elements within the gross reef envelope."

Jan 1, 2001

By N. A. Beier, N. Slingerland

"Oil sands tailings impoundments rank among the largest (spatially) in the world, covering a total of approximately 220 km2 of northern Alberta, Canada. A preliminary geomorphic design for an oil sands tailings storage facility (TSF) landform was completed with the goal of eventual closure and delicensing in mind. This paper outlines methods identified during the design process that streamline closure when implemented early in the mine planning and TSF design stages. With most oil sands TSFs currently in active operation (and some still in the planning stages), geotechnical engineers and mine planners have the opportunity to make operational and design decisions, such as those outlined herein, that are likely to improve the geotechnical and environmental performance of the landform post closure. ¦ KEYWORDS Alberta, Athabasca oil sands (AOS), Landform design, Reclamation, Sand dam, Tailings storage facility (TSF) RÉSUMÉ Les bassins d’accumulation des résidus issus des sables bitumineux font partie des plus grands (en termes d’espace) au monde, et couvrent au total environ 220 km2 dans le nord de l’Alberta, au Canada. Une conception géomorphologique préliminaire a été réalisée pour le modelé d’une installa¬tion de stockage des résidus (ISR) issus des sables bitumineux en gardant à l’esprit la fermeture et le retrait de permis à terme. Cet article présente les méthodes identifiées pendant le processus de conception qui simplifient la fermeture lorsqu’elles sont mises en oeuvre dès les premières étapes de planification de la mine et de conception de l’ISR. La plupart des ISR issus des sables bitumineux se trouvent dans des exploitations actives (dont certaines en sont encore aux étapes de planification), aussi les ingénieurs géo¬techniques et les planificateurs miniers ont la possibilité de prendre des décisions en termes d’exploita¬tion et de conception, telles que celles présentées ici, qui pourraient améliorer la performance géotechnique et environnementale de la phase suivant la fermeture du modelé. ¦ MOTS CLÉS Alberta, assainissement, barrage de sable, conception du modelé, installation de stockage des résidus (ISR), sables bitumineux de l’Athabasca (SBA)INTRODUCTION The Athabasca oil sands (AOS) underlie 140,200 km2 of land in northeastern Alberta, Canada. Oil sands located within 100 m of the original surface account for 4,800 km2 of the total area and are considered to be economically mineable (Figure 1; ERCB, 2009). Bitumen, the thick, tar-like substance contained in the AOS, is extracted through open-pit mining and in-situ methods. During mining, the overburden is first removed as waste and the sandy, bitumi¬nous ore (“oil sand”) is transported to processing facilities via conveyor belts and 400 t trucks. Warm and hot water, as well as process aides such as caustic soda, are mixed with the oil sand, creating a slurry from which bitumen is mobilized and extracted. The resulting slurry waste product is called “tailings” and contains mineral solids, process water, and small proportions of unrecovered bitumen (Masliyah, Zhou, Xu, Czarnecki, & Hamza, 2004; Sobkowicz & Morgenstern, 2009)."

Jan 1, 2019

By P Kovacs, D. L. Flock

For the purpose of reservoir-performance calculations a balance can be made between the materials with-in the reservoir and the production from the reservoir. The material balance equation, a relationship which holds under or near equilibrium conditions, has been used in many forms by the Petroleum Engineer for the determination of initial oil-in-place in the reservoir and the calculation of performance into the future. One of the more recent methods developed by Tracy, utilizes a modified form of the Schilthuis material balance. In the latter case, values of incremental production are assumed for a particular pressure drop, a value of the gas-oil ratio found and a check of this estimate made by calculation"' the initial oil-in-place. Tracy's method utilizes an estimation of the instantaneous gas-oil ratio and by trial and error a value of the gas-oil ratio is

Jan 1, 1961

By R. Stauber, B. Friedrich, S. Hilgendorf, G. Homm, C. Gellermann

Due to recent regulations limiting tolerated lead concentrations in copper alloys, new recycling strategies have to be considered. This study investigates the suitability of technical approaches in order to recycle leaded copper alloys exemplified by CuZn39Pb2 and produce an alloy in compliance with future lead regulations in the European Union. Three pyrometallurgical methods are considered to achieve this goal, namely vacuum distillation, intermetallic precipitation and fractional crystallisation. The impact of essential process parameters i.e. pressure, temperature, time, atmosphere and quantity of additives are identified using thermochemical and kinetic modelling. An experimental implementation reveals a general suitability of all three refining processes. However, the individual efficiency of the different methods strongly differs. Thus, a detailed assessment is carried out in order to provide an evaluation on the efficiencies of these methods from a technological, economical and environmental point of view. Taking a possible industrial realisation into account, the authors recommend the approach of vacuum distillation, although the energy demanded is comparatively high due to the enthalpy of evaporation for zinc, or rather, lead. However, required lead concentrations can be reached quickly without introducing an external element to the material. The prediction of selectivity and evaporation speed, which are immanent variables for a successful implementation, can be validated experimentally. INTRODUCTION In 2016 approximately 1 million tonnes of leaded copper alloy semi-finished goods with an average lead content of 2.1 Ma% have been produced in the European Union (EU). The global production in the same period exceeded 5.5 million tonnes, while the lead concentration has stayed constant at around 2.4 Ma% for the last 50 years. Up to 80 % of the current production volume is covered with end-of-life scraps, which are used for direct re-melting, depending on the alloy composition. Lead has been a popular alloying element in copper alloys in general, and in particular in brass due to its positive impact on various mechanical, physical and chemical properties, especially machinability. Health and environmental concerns were drivers for many governments to implement limitations on lead. In order to further utilise the resource potential of leaded copper scrap, it is inevitable to develop methods to efficiently eliminate lead from circulation as far as possible. (Glöser, Soulier, & Tercero Espinoza, 2013; Soulier, Glöser-Chahoud, Goldmann & Tercero Espinoza, 2018)

Jan 1, 2019

By Marc R. Laflèche, Suzanne Paradis, A. Shirley Péloquin, Harold L. Glbson, Robin Potvin, Pierre Verpaelst

"The Archean Blake River Group is best known from a central volcanic complex in Rouyn-Noranda. This volcano-tectonic depression, delimited by the Hunter Creek fault to the north and the Horne Creek fault to the south, is interpreted to be a cauldron approximately 20 km in diameter. Its western and eastern boundaries are the Flavrian Plutonand the D'Alembert shear zone respectively. The complex has an exposed stratigraphic thickness of 10.5 km. Two cycles, composed of andesitic units overlain by bimodal, andesite - rhyolite units, are observed in the area, and are, in turn, overlain by an andesitic unit interpreted to be the lower part of a third cycle.The southern sector of the Blake River Group, south of the central volcanic complex, is considered to be outside the limits of the cauldron, but partly contemporaneous with it. The maximum stratigraphic thickness exposed in this area is 4 .6 km. At least two cycles occur in this sector. The oldest unit, a pre-cauldron andesitic to basaltic unit, occurs only in the southern part of the sector. In the north, two partial andesite - bimodal cycles, interpreted as contemporaneous with the cauldron volcanism, are observed.The eastern sector of the Blake River Group, east of the central volcanic complex, apparently overlies the complex. Two units are observed in this sector: a lower bimodal unit and an uper andesitic unit. The bimodal unit is coupled with the uppermost andesitic unit of the central volcanic complex to form a cycle, and the andesitic unit is considered to be the uppermost unit of the Blake River Group. The total exposed stratigraphic thickness in the sector is 2.5 km.The western sector of the Blake River Group, north and west of the central volcanic complex, is interpreted as the lateral equivalent of the complex. Three andesite - bimodal cycles are exposed in this sector, giving a total stratigraphic thickness of9 .5 km. The two lower cycles correspond directly to the central volcanic complex cycles; this correlation is facilitated by two stratigraphic marker units observed on either side of the Hunter Creek fault: the Fish-roe rhyolite flow, east of the Flavrian pluton, and a spherulitic rhyolite lapilli-tuff, west of the Flavrian pluton.Many of the volcanogenic massive sulphide deposits found in the central volcanic complex are spatially and temporally associated with synvolcanic faults, and felsic domes and feeder dykes that are the sites of felsic volcanism in the bimodal units. However, these features also occur outside the central volcanic complex, and the similarities recognized in this work between the complex and the surrounding area suggest that such deposits need not be restricted to the central volcanic complex. The presence of volcanogenic massive sulphide deposits outside the complex confirms this."

Jan 1, 1990

By Ozdemir. O.

Magnesium additions to aluminum enhance strength and hardness, lowering density, and improving corrosion resistance. However, during melting and casting processes, significant amounts of magnesium are lost due to selective oxidation. Preventing these losses would reduce the production cost and improve the quality of the final product. The effects of strontium addition on the oxidation behaviour of aluminum-0.5% and 1% magnesium alloys were investigated by monitoring sample weight gains with time with a thermogravimetric balance at 750°C. Sample cross sections have been examined using Field Emission Gun Scanning Electron Microscope.

Jan 1, 2004

By Harry Piers

A RAPID glance over the history of The Mining Society of Nova Scotia shows that in its fifty years of service, which it is now rounding out, the Society has had an honourable career, rendered signal service to the mining industry of the Province, and helped to shape and improve legislation bearing on our mines and minerals, besicles publishing very many excellent papers and subsequent discussions thereon dealing with all subjects in its field of activity. THE GOLD MINERS? CLUB OF NOVA SCOTIA: The Society has the distinction of being generally regarded as the oldest mining fraternity in Canada ( 1). Iris the direct outgrowth or reorganization of The Gold Miners' Club of Nova Scotia, which was organized in March, 1887, at a period when the gold mining industry was very prominent in the Province. Mr. Geo. W. Stuart, who, in 1934, was the only living member of the parent association, informed me that the seventeen Charter Members of The Gold Miners' Club were John H. Anderson, Charles F. Andrews, A. B. Cox, Clarence H. Dimock, George E. Francklyn, L. W. Getchell, John E. Hardman, Alonzo A. Hayward, Major R. G. Leckie, W. L. Libbey, Edward M. McDonald, G. F. McNaughton, George A. Pyke, H. A. Sanders, C. E. Willis, Benjamin C. Wilson, and George W. Stuart. Others joined later in the same year.

Jan 1, 1937

By Shae K. Kim

The aim of this study is to manufacture magnesium alloys with alkaline earth metal oxides (BeO, CaO, MgO or SrO) additions with the objectives of (1) ensuring safety during processing and applications by raising the ignition temperature and reducing oxidation, (2) protecting the environment by reducing or eliminating use of protective gases, (3) maintaining or improving elevated temperature properties with lower amount of Ca or Sr or rare earth metals when compared with conventionally developed high-temperature magnesium alloys, (4) developing cleaner strip casting and continuous casting processes without hot tearing and (5) obtaining all of these objectives without sacrificing mechanical properties or increasing the cost of magnesium alloys.

Jan 1, 2006

By Z. Gostynski

The paper is a historical cross-section through a 28-year period of operation of the direct-to-blister Flash Smelting Furnace in the KGHM Glogów Copper Plant. It presents the origin of the furnace as well as the path of numerous changes and modifications both in technology and process introduced in the furnace in response to the production and cost-reduction challenges. The authors provide justification of the statement that continuous improvement of the "Polish" Flash Smelting Furnace has ranked it among the most modem smelting units in the world.

Jan 1, 2007

By Vincent Jourdain

Located in the James Bay Territory of Quebec (figure 1), the Clearwater property is jointly owned by SOQUEM Inc. and Eastmain Resources Inc. Exploration on the property since the early 70's has resulted in the discovery of several gold showings. Exploration work by the joint venture since 1995 has led to the definition of the Eau Claire Zone containing an indicated resource of 540 000 tonnes grading 11.1 g/t Au (8.7 g/t Au cut at 34.28 g/t Au). Hosted by the archean Eastmain Greenstone Belt, the property geology is dominated by mafic volcanics containing thin horizons of felsic volcanics and/or sedimentary rocks (figure 2). The sequence is metamorphosed to the amphibolite facies and contains two small toalitic intrusions. Regionally, the structural trend is oriented E-W but in the area of the Eau Claire Zone a second trend oriented NE-SW is also present. The first exploration work on the property was conducted by SEREM and SDBJ from 1973 to 1976. It consisted of an airborne electromagnetic survey and a ground follow-up program on several grids. This program, comprising geological mapping, geophysics and drilling, led to the discovery of the Natel showing where a drill intersection returned 8.89 g/t Au over 2.65 m. From 1978 to 1985 the area was withdrawn from staking because of the hydroelectric projects of the James Bay. In 1985, Westmin Resources Limited and Eastmain Resources began an exploration program based on a helicopterborne electromagnetic survey. Once again, a ground follow-up program was conducted on several grids. This program included a soil geochemical survey that identified a strong (up to 10 g/t) gold anomaly. Drilling of the anomaly led to the discovery of the Eau Claire Zone where resources were estimated at 270 000 tonnes grading 6.1 g/t Au at the end of 1990. In 1995, SOQUEM Inc. took an option to gain a 50% interest on the property and obtained its interest in 1998. Since 1995, two principal mineralization zones were identified on the property. The "Rosemary Zone" consists of veinlets and disseminations of pyrite and chalcopyrite within a magnetite-rich amphibolite. The mineralized zone was identified by stripping within an area of 1000 by 500 metres. Drilling indicates copper grades up to 0.32 % Cu over 49.2 m. with locally grades of 0.75 % Cu over 5.9 m. The mineralised zone is associated with QFP dykes and corresponds to a strong magnetic anomaly and a strong copper and molybdenum soil anomaly. The "Eau Claire Zone" consists principally of a set of gold bearing quartz-tourmaline veins oriented E-W and dipping at 45-50??to the south (figure 3). More than ten different veins are recognised in the zone and up to eight veins were observed in a single trench (figure 4). The host rock between the veins shows a degree of deformation similar to the regional volcanosedimentary rocks. Each vein is hosted by a unit of actinolite-tourmaline-biotite schist up to one meter thick. The veins and their hosting schist clearly cross-cut the schistosity of the hosting lithologies and the contacts between amphibolites and felsic to intermediate rocks. Usually, the veins are less than a meter thick and are composed of quartz, tourmaline and calcite. The proportion of quartz and tourmaline varies from 0 to 80% within a single vein. The veins commonly show massive, banded or brecciated texture. Sulphides, mainly pyrite, pyrrhotite and chalcopyrite, generally form less than 5% of the vein material.

May 1, 2001

By K Komori

Naoshima Smelter and Refinery has treated shredder residue and incinerator fly ash in Japan since 2003. As a highlight, a new incinerating and melting furnace, as well as fly ash washing treatment plant were newly constructed for pre-treatment of shredder residue and fly ash respectively, and the pre-treated materials are ultimately treated in the existing Mitsubishi continuous copper smelting and converting process line. Since wastes such as shredder residue tend to vary in size and in shape, and contain some chlorine, the installation of a new pre-treatment line was required. The combination of the new pre-treatment line with the existing Mitsubishi Continuous Copper Process line has created a highly efficient and environmentally friendly system for recovering and recycling of valuable metals that previously used to be sent to a landfill. This paper reviews the approach that Naoshima took to establish its current recycling business strategy.

Jan 1, 2007

By H. Utsunomiya

Most magnesium alloy sheets show low deformability in rolling. Edge cracks and transverse fractures are common difficulties. In addition, rolled sheets show well-developed basal texture <0001>//ND. The texture causes high anisotropy in mechanical properties and low formability in subsequent metal forming. Differential-speed rolling, where the upper and the lower rolls rotate at different speeds, introduces shear deformation through the thickness. Not rolling texture but shear texture evolves in the sheet so that the asymmetric rolling can be a method of texture control. However the primary slip system of the hcp alloy, is basal, the shear texture should be also basal. Differences between the two basal textures, i.e., the rolling texture and the shear texture, have not been understood completely. In this study, conventional (same-speed) rolling and differential-speed rolling have been applied to commercial AZ31B sheets at 623K. Microstructures, textures and mechanical properties of the rolled sheets before/after annealing are compared. It is found that the basal texture is more pronounced by the asymmetric rolling. On the other hand, the asymmetric rolling is effective to decrease the grain size and the planar anisotropy.

Jan 1, 2006

By D. Mu

A method is presented for evaluating the effective gas diffusion coefficient of porous media. A series of random-distributed porous solids with different porosity are generated, a solution of the gas diffusion equations inside the porous media is obtained using the finite element method (FEM), and then the effective gas diffusivities are computed. The results show that there is a percolation threshold sp, and this percolation threshold decreases with an increase in the connectivity of the pore network; the relationship between the effective diffusivity and the porosity is strongly nonlinear when the porosity £ is less than about 0.2; and is quasi linear for higher porosities. The threshold decreases with increasing the connectivity of the pore network. A formula relating the effective diffusion coefficient with porosity is proposed.

Jan 1, 2005

By Takahiko Okura, Chiharu Tokoro, Shunta Shibuya

Copper concentrates bearing arsenic as enargite (Cu3AsS4) or tennantite (Cu12As4S13) have disadvantage on copper smelting environmentally and economically, so those concentrates should be treated decently. In this paper, some experiments of arsenic removal from several kinds of copper concentrates by heat treatment in an inert atmosphere were discussed. In this study, several samples in which arsenic contents varied 0.18 to 8.3 wt % were heated to the temperature range of 400 °C to 700 °C under argon gas flow during 1 hour. The heat residues and volatilized materials (V.M.) were analyzed by XRD, XRF, ICP-AES, XAFS and MLA to analyze residual concentration of arsenic and residual mineral composition. Experimental results showed that arsenic removal from copper concentrates advanced in 2 steps; at the temperature range of 500 ° C to 550 °C and of 550 °C to 650 °C, respectively. MLA analysis showed that a few of arsenic in enargite was removed by 550 °C heating and a majority of it was still combined with copper and sulfur as tennantite. On the other hand, arsenic in tennantite was removed almost completely by 650 °C heating. Furthermore, a particular type of arsenic mineral, such as Cobaltite (CoAsS) still remained after heating at 700 °C.

Jan 1, 2014

By E. S. Moore

"The Michipicoten-Goudreau area, bordering on the northeast corner of lake Suferior, has had a tectonic history related to that of the geosyncline occupied by this lake. This basin has been a major structural feature in the Canadian Shield since at least late-Precambrian time. It has been extensively faulted and was the centre of great igneous activity in the Keweenawan feriod . Many of the faults, folds, dykes, and sills in the surrounding regions tend to head directly or indirectly into this basin. Some of the faults in the Michipicoten-Goudreau area appear to run under the eastern part of lake Superior just as the large Keweenaw fault in Michigan extends into the lake on the south side. Some of these faults may even be extensions of or counterparts of the faults on the south side of the lake. Another set of faults in the Michipicoten-Goudreau area runs nearly transverse to some of these major faults, and it is evident that in some places movement has recurred at a later time on faults formed in an early period.STRATIGRAPHYThe rocks of this area, with the exception of Pleistocene and Recent formations, are all Precambrian:"

Jan 1, 1954

By S. Minamiguchi

Grain refinement is effective to enhance strength and ductility of metallic materials. However this advantage has not been utilized fully for magnesium alloys in industry because microstructure control through thermomechanical treatment is difficult owing to their poor deformability. The authors proposed a high-speed heavy-reduction rolling for production of Mg alloy sheets. It was found that the deformability is significantly improved at high speed and that the thickness can be reduced 60% by one-pass operation even at room temperature without fracture at the rolling speed higher than 1000 m/min. In this study, commercial AZ31B sheets were rolled at 2000 m/min between room temperature and 350°C, and quenched immediately after the rolling. The sheets rolled at 200°C show the finest recrystallized microstructure with the mean grain size of 2.2 Rm. They show outstanding mechanical properties with the tensile strength of 293 MPa, and the elongation of 25%. It is concluded that high-speed rolling is very advantageous for grain refinement and improvement in mechanical properties as well as deformability and productivity.

Jan 1, 2006

By LeRoy A. Thorssen

The use of lightweight aggregate as a constituent of concrete is not a recent development. Pumice was used by the early Romans, in pozzolana cement concretes, in the construction of many of their works. However, the recent development of manufactured lightweight aggregates, such as the expanded shales, vermiculite and perlite, has created a possible use for a whole new group of Portland cement concretes. Concrete can now be produced with unit weights ranging from 30 to 150 pounds per cubic foot and with various insulating, fireproofing, acoustical and structural properties. The tonnage of such materials being used has increased considerably in each of the past ten years, and can be expected to increase for the next several years as availability of the aggregates becomes more widespread and the properties of such concretes become more thoroughly investigated and more generally known. LIGHTWEIGHT aggregates of many types have become avail-able to the construction industry in most localities on this continent

Jan 1, 1963

By D. L. Thompson

Foreword The complete history and early development of the Sullivan mine was fully covered in a paper entitled &apos;The Development of the Sullivan Mine and Processes for the Treatment of its Ores&apos;, prepared by the staff of the Consolidated Mining and Smelting Company of Canada, and presented at the Annual Meeting of the British Columbia Division of the Institute at Trail in October, 1924. At a subsequent meeting at Blairmore, Mr. E. G. Montgomery read a paper on the mine, and in 1926 Mr. M. M. O&apos;Brien brought the subject up to date at the joint meeting of the American and Canadian Institutes at Cranbrook. The present paper is necessarily based largely on these earlier accounts. Discovery and Early Development The outcrop was discovered in 1892 and the property was bonded and later sold to the Sullivan Group Mining Company, of Spokane. From 1896 to 1899, surface stripping and test pits (at A) around the outcrop exposed a vien of sulphides with varying amounts of lead and zinc. In some places, a 35 per cent lead ore carrying 15 ounces of silver was found. These lenses were of commercial value. With the completion of the Kimberley branch of the Canadian Pacific railway, in 1900, some systematic development was started. A shaft l00 feet in depth was sunk (at B). Shaft-house, boiler-room, and compressor-plant were erected, and a steam diamond-drill was put into operation.

Jan 1, 1929

By W. D. Robbson

DR. G. W. RAMSEY (l): A study of our non-treatment silicosis autopsy material for the years 1940-43 inclusive, in addition to the common findings of fibrosis, nodules, and emphysema, shows marked thickening of the alveolar walls. This change is due to one or more of the following factors: congestion, edema, accumulation of both small and large monocuclear cells within the interstitial tissues and large monocuclear cells attached to the lining membrane of the alveolar sacs. This alteration in the alveolar walls, we believe, is one of the most important factors in producing impaired pulmonary function. Comparison of our first autopsy material of a case receiving twenty aluminium treatments beginning June, 1943, shows a striking change in the alveolar walls. In all areas free of silocotic nodules and fibrous tissue, the alveolar walls approach normal thickness and are free of cellular deposits. No change was noted in the old processes and none was expected. We believe that these changes in the alveolar walls were brought about by the aluminium therapy and that they constitute a major factor in the improved pulmonary ventilation noted in treatment cases.

Jan 1, 1945

By David W. Smith

"This paper is devoted mainly to a discussion of the hydrocarbon potential of the offshore, with a few brief remarks concerning the inorganic mineral potential.OFFSHORE OIL AND GAS POTENTIALIN ORDER TO HAVE HYDROCARBON ACCUMULATIONS, we must satisfy three basic requirements. First, we re-quire a sufficient thickness of sedimentary rocks which contain some porous and permeable formations to act as reservoirs. Second, we require some type of trapping mechanism, such as faulting, folding or stratigraphie trapping. Finally, we require that large quantities of hydrocarbons have been generated within the sedimentary rocks and have migrated to the traps."

Jan 1, 1969