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18th International Petroleum and Natural Gas Congress and Exhibition of Turkey
- Conference date: 11 May 2011 - 13 May 2011
- Location: Ankara, Turkey
- Published: 11 May 2011
101 - 120 of 163 results
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Stratigraphy, Sedimentology and Geochemistry of Dadaş Formation as an “Unconventional Reservoir”
Authors A. Güzel, H. Çorbacıoğlu, N. Bozdoğan, Y.H. İztan, A. Aydemir and P. BeşerShales bearing abundant amount of organic materials can generate oil and gas by the thermogenic variations of the contained kerogen under the conditions of increasing burial pressure and heat. Some of the generated fossil fuels are expelled from these source rocks but majority of them are still confined. Those unexpelled hydrocarbons are considered as a new energy source and being produced by the application of unconventional techniques recently developed in North America. The shales being source rock may be a new energy resource for natural gas if overheated (Ro>1.2) or for oil in existence of under-normal heat influence (Ro=1.2). Shales have been considered as seal or source rocks up to date. However, they recently need to be analysed and investigated with different techniques and new point of view, because they are accepted another type of reservoirs as well, and they need to be studied for lithology, faciess distribution, petrographic, minerological and geochemical composition, porosity & permeability parameters, clay silica and carbonate contens and compositions and fraccability of them. In addition, new rock mechanics analyses and extra lab-works are also demanded because plastic, elastic and fraccability characteristics of shales directly involve to the operational success. Moreover, distinguishing organic and litho-faciesses of the production intervals are also crucial for the unconventional operations and horizontal drilling that becomes a standart for the unconventional industry. Silurian Dadas Formation which has very vast extension (12.000 km2) in the SE Anatolia, has been accepted as the main source rock for the “palaeozoic oil system” and the oil fields around Diyarbakir, similar to the Middle East and North Africa. This study aims to investigate the convenience for being an unconventional resource and evaluation of the Silurian deposits (Dadas Formation) having thicknesses up to 400 m in the SE Anatolia. While investigating whole Dadas section, potential intervals and their characteristics, their extension and propagation with potential faciesses, palaeogeographic properties in the study area have also been described by the help of lab results. In addition, prospective zones for shale gas and shale oil are aimed to determine together with the descriptions given above.
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Shale Gas and Possible Effects on World Energy Market
Authors V. Dedeoğlu and A. ŞengelIn recent years, increasing oil prices cause an increase in natural gas prices. Therefore, this results directs countries and companies to unconventional resources. New technologies are supporting the removal of shale gas. As a result, the shale gas reserves which are spread over different parts of the world, will affect energy policies and trends of countries.
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Reitbrook, a Successful Conversıon of a Former Complex Oil Field into Underground Gas Storage
Authors C. Bontemps, P. Egermann, R. Foerster and G. GerkenReitbrook is a former oil field located in the North of Germany in the periphery of the Hamburg city. The field was discovered in 1937 and developed directly the years afterwards. Depth is 700 m/sl and oil was reputed to be closed initially close to the saturations conditions. The initial reservoir pressure was 84 bars and the oil has a specific gravity of 22 API. The field belongs to the Cretaceous period and the reservoir consists in a massive tight and fractured chalky limestone formation. The structure is a moderately faulted dome overcoming a salt dyapir of Zeichstein. The reservoir thickness varies from 65 to 80 metres. Despite a porosity of 25%, the matrix porosities range low values of 0.1 to 1 md due to the small thresholds of the porous media. At the opposite, dynamics data resulting from the well performances shows presence of permeabilities of 1 to 2 Darcy as a result of natural fractures distribution. Oil production reached a peak of 360 000 tons per year in 1940 after the drill of more 200 wells. In the period 1940-53, an injection of gas was implemented followed by a water injection in 1956. In 1964 until the abandonment exploitation achieved in 1973, the gas and the oil were exploited conjointly during a blow-down phase. In 1973, the decision to convert this oil field into underground gas storage (UGS) was taken and an intensive recompletion campaign of oil wells in gas wells and observation was made. In 1979, a first phase of the conversion was achieved with a capacity of 150 Mcum3 of working gas volume associated to a withdrawing rate of ca 200 000 m3 per hour. After the success of this first step, the gas capacity was extended by optimizing the strategy of the injection and withdrawing campaigns. Currently the capacity is 350 Mcum3 of working gas and 350 000 m3 per hour of the nominal withdrawal rate. Reservoir pressure varies between a maximum of 80 bar (beginning of the winter) and a minimum of 40 bar (end of the winter).Currently 78 wells are used as gas producers, water and oil producers and observation wells. To achieve such performance, vertical and horizontal liquid producing wells were drilled in the down-dip parts of the field. Such wells allow to limit the injection gas compression capacities by decreasing the reservoir pressure, by reducing the liquid breakthroughs in the up-dip gas wells. Thus, the partial invasion of matrix by the injected gas through the natural factures is acting as an enhanced oil recovery process. The oil expulsed from matrix and segregated by gravity in the fractures network is produced by these down-dip liquid wells. So far, oil is produced at an attractive and sustained rate. Experience of the increase of the gas storage capacities showed that more oil could be mobilized. In conclusion, despite a long past exploitation, Reitbrook has found a second life by combining in parallel oil production and the gas storage activities. Experience and the skills of the GDFSUEZ group in both domains of the Exploration/Production and the UGS has allowed to implement a win-win system permitting to delay the Reitbrook oil field abandonment, to develop business in gas transportation and domestic marketing and to continue to produce oil from a very mature field.
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3D Geostatistical Model of the Soğucak Reservoir in the Değirmenköy Gas Field
Authors S.T.T. Kamanlı, Y.Ş. Karakeçe, S. Mağara and M. AkpınarIn Turkey natural gas reserves and productions are very small, so, the majority of natural gas is imported from abroad. Due to natural gas crisis in the world and seasonal consumption differences, the construct of underground natural gas storage tanks has become mandatory. In order to increase the energy security of the country, K.Marmara and Degirmenkoy mature natural gas field were evaluated by TPAO and Turkey’s first underground gas storage tanks were built and started to be used for storage in April of 2007 In this study, borders of Değirmenköy (Soğucak) Field was determined by using new 3D seismic studies and the creation of 3D geological model which form the basis of simulation work which will guide the capacity increase study was explained.
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Reservoir Engineering and Simulation Study for Natural Gas Storage in Değirmenköy Field, Soğucak Carbonates
Authors V.V. Üstün and M. YılmazTo support Turkey’s energy sustainability, two gas storage facilities, K. Marmara and Değirmenköy, have been constructed and is being operated by TPAO. After many years effort and studies these underground storage fields put on operation 4 years ago. Still, the present daily flow capacities of these fields needs to be increased and new wells have to be added to the system. In the study, the production and injection flow rate contribution of new wells were evaluated. This paper contains flow test results for the wells drilled through Soğucak carbonates, and reserve data for this formation which was achieved with material balance method. The natural gas withdrawal and injection rates of prospect wells were found using reservoir simulation. For this method, dynamic model was created by adding fluid properties and production-pressure data to the geological model. History matching was performed by using daily gas flow rates, well head pressures and also some bottom hole pressures. Then, various storage scenarios were considered with new wells and annual working volumes with daily injection-production rates were calculated for each scenario.
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Integrated Geostatistical Reservoir Characterization And 3D Geological Modelling Study of Yulaflı Field
Authors C. Çetinkaya, M. Akpınar, F.S. Mağara and Y.Ş. KarakeçeGas demand in the years of our country, consistently shows an increasing trend, hence there is an urgent need for new storage fields. Yulaflı Field is studied as thought to be a part of the Thrace Region Underground Gas Storage Project. This study has been conducted in order to calculate volume of gas in place by 3D geological modelling of Yulaflı Field and to provide a basis to underground gas storage simulation studies with an integrated reservoir characterization study, taking into account the sequence stratigraphy studies previously done, including seismic interpretations, structural properties, well log data, well correlations and production data. In the fields, which have limited number of wells such as Yulaflı, a geological model has not been sufficient to demonstrate the character of the reservoir by using only well data, thus, a secondary data set has to be used. In this study, the interpretated well log data and seismic data have been properly integrated and used in a combination. Thus, a more accurate and detailed 3D geological model was created representing the reservoir characterization of the field.
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Reservoir Simulation Study for Underground Gas Storage Project of Yulaflı Field
Authors M.E. Gözel and M. YılmazIn recent years, gas demand and supply policies have become very important issues for the gas importing countries. Turkey, as one of the natural gas importers, has fields used for underground gas storage projects. Yulaflı Field, one of the possible storage fields in future, has been studied to determine the UGS capacity of field. Yulaflı Field, which is located in SE Thrace Basin, has been producing from sandstone layers of Danismen and Osmancık Formations since 2000. Seven wells have been drilled until now. Currently, the field has a production of 35000 m3/day with 3 active wells. Using previous sequence stratigraphy studies of Yulaflı Field, three dimensional (3D) geological model has been created by Petrel software in order to use in simulation studies. In geological model, well log and seismic data have been used to distribute reservoir parameters throughout the field. In order to develop Underground Gas Storage Project in Yulaflı Field, numerical simulation studies were performed using Petrel and Eclipse software. Production history has been matched with simulation model. As a result, storage capacity of field and injection-production scenarios were studied.
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Modeling of Coalification in Soma Coal Basin
Authors M.N. Yalçın, K. Tırpan, S. İnan and F. DuygunThe Soma Coal Basin, located in the northeastern part of the Aegean Horst-Graben System, is an extensional basin trending in SW-NE direction (approximately 20 kilometers by 5 kilometers). Turkish Coal Enterprises (TKİ) estimates at least one billion tons of lignite and about half of this reserve is present at depths greater than 600m. There are three distinctive coal seams within the coal-bearing Miocene sequence. But, only stratigraphically the lowermost seam, named as “Lower Coal Seam-KM2” is the target of exploration and exploitation efforts. The KM2 interval is being mined by open-cut coal mining and underground mining in the Northern and Central part of the basin, respectively. An underground mining is also planned in the Southern part of the basin. Therefore, exploratory drillings are being conducted here in order to plan the exploitation.
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From Petroleum Era to Where?
By C. ÇoruhIntensified “Peak Oil” discussions impose important economical and social questions that directly affect professions in petroleum exploration and production while increases importance of expectations from them. On the other side, continuing successes of these professions are continuously modifying the data that is the base for “Peak Oil” projections. In these contexts,since “Petroleum Era” will retain its importance for a couple of generations, under the light of past developments and recent projections, elaborations are presented on importance of professions of petroleum exploration and production and expectations from them.
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The Coalification Process and Use of Biomarker Data in the Determination of Paleoenvironmental Characteristics; Karapınar Coals (Konya, Turkey)
Authors O. Özçelik, M. Altunsoy, S. Hökerek, N.Y. Erik, M. Taka and F. AcarThe coalification process and depositional environment of the Pliocene Karapınar Coal Deposit (Konya) in Central Anatolian (Turkey) were investigated by organic geochemical methods. The coal samples are characterized by the occurrence of C29 steranes in the saturated hydrocarbon fractions, while the C27 and C28 homologues are present in low quantities (C29>C27>C28). The dominant hopane in samples are moretane and normoretane. Based on the C28/C29 sterane ratios, these coals are Tertiary in age, and this conclusion is in full agreement with the geological age. Differences in diasterane/sterane ratios exist within the coal samples, and these high ratios show both acidic and oxic-suboxic environments. Relatively high concentrations of C23 tricyclic terpane in investigated sample extracts indicates terrigenous input. The dominant sterane in all samples is C29, indicating a terrigenous contribution consistent with the predominant origin for the organic matter having been from land plants. Also, richness in C27 indicates a lagoonal environment and algal organic material in that environment; the C28 levels are quite low and typical of limnic environments. βα-Moretane / αβ-hopane ratios indicate the immature early mature stage and gammaceranes are related to organic matter deposited in high-salinity depositional environment.
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Organic Geochemical Analysis of Beydili Kayası (Nallıhan/Ankara) Bituminous Shales
More LessBituminous shales of Beydili Kayası are accumulated in disoxic and anoxic redox conditions, and have an average organic matter (TOC) contents of 6.15 wt. %. Average 0.5 wt. % TOC is considered as an economical limit for rocks producing oil, thus the values of TOC of studied shales show an excellent source rock potential with an average of 6.15 wt. %. In addition to Total Organic Carbon analysis, Pyrolysis (HI, OI, Tmax, S1, S2, S3) analysis, Gas Chromatography (GC) analysis, Thin Layer Chromatography (% Saturate Hydrocarbon, % Aromatic Hydrocarbon, % Polar, % Asphaltene) analysis, Isotope analysis and Organic Petrography analysis (in backlit microscope) were done in samples of Beydili Kayası, and organic matter types, maturities and hydrocarbon potentials of studied samples were determined. Organic matter types of studied samples are generally type I kerogen, and have oil production potential. Maturity of studied samples were determined that they have immature and early mature degree. The S1 type hydrocarbons of the studied samples show that no organic contamination is present in the area.
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Factors Controlling Element Composition Variations of Organic-Rich Rocks (Taşpınar/Nallıhan)
More LessSamples investigated in this work are composed from Paleocene-Eocene organic-rich black shales and marls of Çamalan Formation. Several geochemical (organic and inorganic) and mineralogical analysis were used for determining the factors controlling composition variations and source rock of Taşpınar organic-rich rocks. 52 samples taken from the study area suggest an average of 2,97 %wt. of organic carbon values, with a range between 0,12 and 11,32 %wt. Mineralogical analysis of 5 samples show that these rocks are mainly composed of dolomite, quartz, clay minerals, analcime, mica group with traces of feldspar and calcite. Furthermore Chemical Alteration Index (CIA) values indicate that Taşpınar samples were generated from a moderately weathered source rocks. Results of redox conditions of depositional environment obtained with several geochemical parameters such as Ni/Co, V/Cr, U/Th, and the relationship between Corg with certain elements show element compositional variations of samples. While average ΣREE values of Taşpınar samples indicate a higher ratio relatively to chondrite, these have lower ratios with average shale, PAAS, UCC.
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Rare Earth Elements Enrichments of Organic Matter Rich Rocks in the South of Dağşeyhler Village
More LessRare earth element content of samples which are collected from the study area were determined by ICP-MS method. REE distrubitions are as follows, claystone:63.94-176.41 (120.17) ppm, carbonaceous claystone 43.19-85.97 (63.68) ppm, marl:2.96-74.25 (33.80) ppm and oil shale:26.46-79.28 (50.68) ppm. REE contents show a decreasing trend from claystone to marl samples. This situation can indicate that REEs were transported with clay minerals to the depositional environment. REE contents of oil shale are higher than marl, however lower than claystone. LREE/HREE ratios relatively are high in all lithologies. These ratios are as follows, claystone: 4.14, carbonaceous claystone: 3.24 marl: 2.87 and oil shale: 2.83. This situation indicates that REEs were transported with clay minerals to depositional environment and clay minerals control the concentrations of the light rare earth elements. When REE contents of all samples normalized to UCC and PASS values, weak Ce anomalies and positive Eu anomalies were determined in all samples. Weak Ce anomaly indicates partially lower oxygen conditions, whereas positive Eu anomaly indicates presence of Ca-bearing minerals.
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Clastic-Carbonate Facies of Çaybağı Formation (Late Miocene-Early Pliocene), Eastern Elazığ, Eastern Turkey
Authors C.K. Taşgin and İ.̇ TürkmenThe Çaybağı Formation located between Çaybağı and Kovancılar (eastern Elazığ) comprises fluvial and lacustrine deposits. Fluvial deposits are represented braided and low sinuosity river facies. The braided river deposits is characterized by parallel bedded conglomerate, planar cross-bedded conglomerate, planar-trough cross-bedded sandstone, low-angle cross bedded sandstone, parallel laminated sandstone and massive red mudstone. The low-sinuosity river deposits consist of parallel bedded conglomerate, planar-trough cross-bedded conglomerate, planar-trough cross-bedded sandstone, ripple-cross laminated sandstone, parallel laminated sandstone, sitstone, carbonaceous mudstone, massive red mudstone, gray claystone, clayey limestone and turba. The gray claystone and clayey limestone contain freshwater ostracods, gastropods and pelecypods. Lacustrine deposits compose of three main facies associations. These are delta, shallow lacustrine and open lacustrine. The delta deposits were grouped into subassociations; delta top, delta front and prodelta (open lacustrine). Facies in delta top subassociation are represented by parallel bedded conglomerate, planar-trough cross-bedded sandstone as channel deposits, parallel laminated sandstone, siltstone as levee deposits, red mudstone, gray claystone as flood plain deposits, clayey limestone as ponded water and carbonaceous mudstone and peat as swamp deposits. Two type of delta front subassociation were recognised; gilbert-type delta front subassociation and mouth-bar type delta front subassociation. Facies in the gilbert-type delta front subassociation are represented by parallel bedded conglomerate, parallel laminated sandstone as topset deposits, large-scale cross-bedded conglomerate up to 5 m thick as foreset deposit and low-angle cross bedded conglomerate, planar cross-bedded sandstone, parallel laminated sandstone as bottomset deposits. The mouth-bar type delta front deposits compose of parallel bedded conglomerate, planar-trough cross-bedded conglomerate, planar-trough parallel laminated sandstone and siltstone. The shallow lacustrine environment is represented by parallel laminated sandstone, siltstone, carbonaceous mudstone, gray claystone, clayey limestone, marl and turba. Fine-grained facies such as carbonaceous mudstone, gray claystone, clayey limestone, marl in this margin environment contain abundant ostracod, gastropod, pelecypod and charophytes fossils. The peats ovelie the carbonaceous mudstone and clayey limestone. There are rhizolits in the carbonaceous mudstone, clayey limestone near their upper contact with the peat. The clayey limestone contains abundant leaves and other plant fossils. The offshore lacustrine deposits consist of carbonaceous mudstone, gray claystone, clayey limestone and marl. These lithofacies contain poorly preserved fosil remains, freshwater ostracods and rare freshwater gastropod.
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An Example of Siliciclastic, Carbonate and Evaporite Transitions: Sivas Eocene Basin, Central Anatolia
Authors Ö. Kangal, B. Varol, H. Temiz, A. Poisson and L. KaradenizliSivas Tertiary Basin is one of the most important basins in Central Anatolia. The closure of the northern branch of Neo-Tethys Ocean during the Early Tertiary is determinant phenomenon in the evolution of this area like other Tertiary basins in the Central Anatolia, such as Çankırı-Çorum, Haymana-Polatlı, Tuz Gölü and Ulukışla Basins. The basin is extended to the northeast-southwest direction, and, narrowed and closed in the east. The Sivas basin is bordered by the Pontide belt in the north, Tauride belt in the south and Kırşehir Massif in the west. The Eocene deposits of Sivas basin show important environmental and lithological diversities reflecting evolution of a basin developed on suture zone. Deposition systems are possessed environmental characteristics that are defined by the assemblages of siliciclastic, carbonate and evaporate facies. Especially within the coastal belt, these transitional environments that are formed by siliciclastic and carbonate assemblages are progressed towards offshore depending on the changing of the sea level. The aim of this study is examination of vertical and horizontal relationships in such different environments, and evolution of the basin during Eocene.
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High Frequency Paleoclımate Change: Impact on Exploratıon Strategy
More LessOrbital cycles alter insolation, which produces climate, sediment yield, lake & sea level cycles. The greatest insolation changes occur at the scale of precession (~20 kyrs) during periods of high eccentricity. Within a hemisphere, the climatic response of a specific region is a function of the phase of the insolation cycle & the paleogeography of the region. Some areas can become wetter while others become drier at the same point in an insolation cycle. Climate cycles affect the type & rate of sediment weathering & transport, the sediment produced, grain sizes, & yield. Analysis of yield as a function of climate indicates that volume can vary by more than an order of magnitude depending on the conditions. Therefore, a climate cycle can produce a distinct sediment supply cycle, whose nature is dependent on the regional climate succession. An added complexity, similar in some respects to the systematics of annual seasonality, is that precession-scale insolation cycles cause the warmest (or coolest) conditions in the Northern & Southern Hemispheres to be about 10 kyrs out of phase. This is significant because the affects of glacioeustasy, also a function of insolation & climate, are global. Prior to the Plio-Pleistocene, the common glacial state was a unipolar icecap. Under this condition, eustasy tended to track the precession-scale insolation cycle of the glaciated hemisphere. The results were that similar climatic successions in opposite hemispheres had yield cycles with distinctly different phase relationships to glacioeustasy. Such differences would not exist in an ice-free world. Understanding the inherent paleoclimatic & stratigraphic variability of a system helps improve depositional models & interpretation, & reduces the uncertainty associated with exploration analyses. For example, by taking into account the interaction of sediment yield & sea level, exploration areas that are prone to the development of sand-rich submarine fans or deltas can be forecast & high graded. The same approaches can be used for lacustrine regimes. Additionally, evaluating the stratigraphic record & recognizing that these types of variability occur & mapping them in an accurate chronologic framework will greatly assist paleoclimate modelers by ensuring that simulations are run with the appropriate input parameters and by validating their simulations at the appropriate timescales.
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Determination of Cuttings Transport Properties of Aerated Drilling Fluids
Authors A.M. Özbayoğlu, R.E. Osgouei, M.E. Özbayoğlu and E. YükselTwo-phase (water-gas or water-cuttings) and three-phase (water-gas-cuttings) flow is studied in eccentric annular pipes. An annular pipe configuration with rotating inner pipe at different controllable speeds under different inclination angles is used. Experiments using different inclinations are implemented; flow videos, pressure drop values are collected. Liquid, gas flow rate, pipe inclination angles, cuttings penetration rate, inner pipe rotation speed are controllable parameters. Different flow patterns, liquid holdup, pressure drop, cuttings concentration and cuttings speed values are measured using different input values. Appropriate empiric and mechanistic models are developed. Also, a novel approach different than most studies in the literature is used by obtaining all mentioned flow properties except pressure drop by using flow images through implementing image processing techniques. There is a lack of research in literature for inclined annular pipe experiments for flow patterns identification, liquid holdup estimation, cuttings concentration estimation, cuttings transport characteristics using image processing models. The experimental data is tested using the models developed in this study, provided in literature, and some artificial intelligence techniques. Developed models had good overall performances.
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Stiff Foam Drilling in High Loss Formation - A Field Case Study
More LessIn our geological area it is a common fact to encounter formations while drilling; which are subnormally pressured, cavernous/vugular or extremely porous. In the lithological section of our field case study within two formations sequentially, highly vugular carbonates were foreseen. It has also been practised dramatically that curing losses in these formations with the usage of LCM pills or cement plugs are mostly ineffectual. As a result, total losses had occurred a while after reaching a hydrostatic pressure more than maximum allowable pore pressure during drilling with a conventional mud. Underbalanced drilling methods employs drilling fluids of dry air, gas, mist, foam and aerated mud. Among the existing low-density fluids in underbalanced drilling, stiff foam drilling is used in our case study due to many reasons. Foam drilling consists of a surfactant and air. But, stiff foam is constitued with an addition of a propping agent such as a polymer etc. In conjunction with a foaming agent, low polymer concentration provides the effective viscosity to maintain required cuttings transport capacity. The stiff foam results in a lower energy requirement and lower annular velocities as compared to mist or air drilling which was essential in our case due to drilling up to 3000 ft open hole well. This field case study covers the necessities of the application, the procedures and process which are followed,the hydraulics model calculations, the problems encountered while drilling and the proof of the success via the comparison of cost analysis against a former well having similar sections.
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Designing Lost Circulation Pills for Polymer Based Drill-In Fluids
Authors A. Kahvecioğlu, İ.H. Gücüyener and S. AkınSpecially designed non-damaging lost circulation pills (LCP) are being effectively applied for drilling depleted zones worldwide. Optimizing the LCP compositions stop the lost circulation effectively and protect the production zone from liquid and solids invasion significantly. Shape, particle size distribution and concentration of the lost circulation materials (LCM) are key parameters determining the effectiveness of LCP. In this study, the Permeability Plugging Apparatus (PPA) is utilized to evaluate effectiveness of various LCM’s in curing the lost circulation. Sized calcium carbonates are used as LCM in different concentrations and in different particle size distribution. Lost circulation zones are simulated using the ceramic disks and slotted disks. Ceramic disks with nominal pore sizes 20, 35, 60, 90, and 150 microns are characterized in terms of pore size distribution using the computerized image analysis technique. Filter cake quality, spurt loss and filtrate volume are basic parameters to be evaluated in this study. Tests are performed at 75 F and 300 psi of differential.
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New Data and Interpretation on the Development of the South East Anatolian Orogenic Belt
By Y. YılmazThis paper describes the orogenic evolution of the South East Anatolian orogenic belt based on new geological,geochemical and geophysical data. Southeast Anatolia underwent two major stages of nappe emplacements. The first one occurred during the late Cretaceous. During this period a giant ophiolite slab and some thrust slices dragged under the obducting ophiolite were emplaced on to the northern edge of the Arabian Platform. This ophiolite and the other constituent tectonic elements represent a supra subduction zone proto ophiolite which is dated to be about 90 m y old, and formed as a result of the northerly subducting of an older oceanic lithosphere (Southern branch of the Neo Tethyan ocean) which had been generated during the Late Triassic-Jurassic period. The total consumption of this older oceanic lithosphere led to a collision between the forearc of the newly developed SSZ ophiolite and the Arabian Plate. This emplacement event survived from the Turonian till the end of Early Maastrichtian period.
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