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67th EAGE Conference & Exhibition
- Conference date: 13 Jun 2005 - 16 Jun 2005
- Location: Madrid, Spain
- Published: 13 June 2005
1 - 100 of 683 results
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A Filter Bank Solution to Absorption Simulation and Compensation
By R. FerberIn this paper I present a digital filter bank solution to the problem of simulating or compensating the effect of absorption on seismic traces. I stay in the context of frequency-independent Q models for attenuation and dispersion. The key benefit of the outlined technique is that it can deal with arbitrarily time-variant Q i.e. is not limited to the case of mild variation of Q with time. Introduction Absorption simulation or compensation filtering in the context of this paper refers to the application of digital filters with the
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Reserves Determinations – An Independent Consultant's Observations
More LessEXECUTIVE SESSION NO PAPER AVAILABLE
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An Operator's Classification of Reserves and How to Determine Them
More LessEXECUTIVE SESSION NO PAPER AVAILABLE
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Measuring/Modelling Ultimate Production Systematically
More LessEXECUTIVE SESSION NO PAPER AVAILABLE
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How Oil Price Affects Reserves Disclosure
By Sergio PalmaEXECUTIVE SESSION NO PAPER AVAILABLE
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Simulation Study of Co2 Retention During Tertiary Eor Flood in Ivanic Oilfield
Authors B. Goricnik, D. Domitrovic, S. Šunjerga and D. VulinA017 SIMULATION STUDY OF CO2 RETENTION DURING TERTIARY EOR FLOOD IN IVANIĆ OILFIELD D. DOMITROVIĆ 1 S. ŠUNJERGA 1 B. GORIČNIK 2 D. VULIN 2 1 1 INA-Naftaplin Šubićeva 29 Zagreb Croatia 2 University of Zagreb – Faculty of Mining Geology and Petroleum Engineering Pierottijeva 6 Zagreb Croatia The outset of industrial age has been accompanied with a steady increase of atmospheric concentration of carbon dioxide (CO2) from anthropogenic sources mainly from fossil fuel combustion within energy sector as well as from other industrial activities. Ever since the adverse effect of the process on climate change (i.e. global warming) has
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Monitoring Techniques Applied for CO2 Injection in Coal
Authors P. Winthaegen, F. van Bergen, H. Pagnier, B. Jura, Z. Kobiela and J. SkibaA018 Monitoring techniques applied for CO2 injection in coal Abstract 1 To demonstrate that CO2 injection in coal under European conditions is feasible and that CO2 storage is a safe and permanent solution and that coal bed methane can be produced in the same process the EC funded RECOPOL project is being carried out. In order to improve the understanding of storage in coal to verify that safety and environment are not jeopardised and to determine that the CO2 is injected into the intended coal layers an extensive monitoring programme is applied. This monitoring programme is based on FEP analyses
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The Mechanical Impact of CO2 Injection
Authors B. Orlic and B. SchrootA019 Abstract The mechanical impact of CO2 injection 1 B. ORLIC B. SCHROOT Netherlands Institute of Applied Geoscience TNO – National Geological Survey PO Box 80015 3508 TA Utrecht The Netherlands. The mechanical impact of CO2 injection into a depleted hydrocarbon field or aquifer is caused by changes in the stress field resulting from changes in the pore pressure and volume of the rock. Mechanical processes can lead to the loss of reservoir and caprock integrity and the reactivation of existing faults. A geomechanical numerical modelling approach to determining the mechanical impact of CO2 injection is presented and demonstrated on
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Modeling Halite Precipitation around CO2 Injection Wells in Depleted Gas Reservoirs
Authors A. Battistelli, T. Giorgis and D. MarzoratiA020 Modeling halite precipitation around CO2 injection wells in depleted gas reservoirs Abstract 1 Precipitation of solid NaCl (halite) is known to occur both at producing wells during exploitation of gas reservoirs and at gas injection wells in aquifer storage fields where high salinity brines are present. Water vaporization into the gas phase is the recognized mechanism responsible for salt concentration in the residual brine which can be followed by solid salt precipitation with rapid loss of formation permeability. Halite precipitation has also been anticipated by numerical modeling of CO2 injection in saline aquifers for greenhouse gas sequestration in geological
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Capillary Alteration of Shaly Caprocks by Carbon Dioxide (SPE94183)
Authors P. Chiquet, D. Broseta and S. ThibeauSPE 94183 Capillary Alteration of Shaly Caprocks by Carbon Dioxide P. Chiquet and D. Broseta SPE Laboratoire des Fluides Complexes U. of Pau and S. Thibeau SPE Total Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s).
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K12-B a Test Site for CO2 Storage and Enhanced Gas Recovery (SPE94128)
Authors L.G.H. van der Meer, E. Kreft, C. Geel and J. HartmanSPE 94128 K12-B A Test Site for Co2 Storage and Enhanced Gas Recovery L.G.H. van der Meer SPE E. Kreft SPE and C. Geel TNO Environment and Geosciences J. Hartman GDF Production Nederland Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject
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Detailed in Situ Stress Measurements for Qualifying the Safety of Underground Gas Storage Overburden (SPE94253)
Authors D.M. Fourmaintraux, A.-P. Bois, C. Le Goff and S. CantiniSPE 94253 Detailed in Situ Stress Measurements for Qualifying the Safety of Underground Gas Storage Overburden D.M. Fourmaintraux SPE Total E&P; A.-P. Bois SPE APB Consulting; C. Le Goff Total IGF; and S. Cantini SPE Schlumberger Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers
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Efficient Wellbore Cement Sheath Design Using the SRC (System Response Curve) Method (SPE94176)
Authors D. Fourmaintraux, A.-P. Bois, C. Franco, B. Fraboulet and P. BrossolletSPE 94176 Efficient Wellbore Cement Sheath Design Using the SRC (System Response Curve) Method D. Fourmaintraux SPE Total E&P; A.-P. Bois SPE and C. Franco APB Consulting; B. Fraboulet SPE and P. Brossollet Total E&P Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and
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Sparse Radon Transforms with Bound-Constrained Optimization
By A. GuittonA025 1 INTRODUCTION SPARSE RADON TRANSFORMS WITH BOUND-CONSTRAINED OPTIMIZATION ANTOINE GUITTON Department of Geophysics Stanford University Stanford CA 94305 USA Radon transforms are popular operators for velocity analysis (Taner and Koehler 1969; Guitton and Symes 2003) noise attenuation (Foster and Mosher 1992) and data interpolation (Hindriks and Duijndam 1998; Trad et al. 2002). One property that is often sought in radon domains is sparseness where the energy in the model space is focused without transformation artifacts. Sparseness is especially useful for multiple attenuation and interpolation. In practice depending on the radon transform sparseness can be achieved either in the Fourier
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2D Deconvolution for OBC Data and for Internal Multiple Attenuation – Part 1 – Theory
Authors P. Hugonnet and C. TichatschkeA026 2D deconvolution for OBC data and for internal multiple attenuation – Part 1: Theory Abstract 1 We present herein the extension to the OBC case of a 2D pre-stack predictive deconvolution originally designed for surface-related multiple attenuation of streamer data. The formulation of this extension can also be applied for internal multiple attenuation. However while it is strictly exact for the OBC case it is probably rather an approximation for the internal multiples. Part 1 of this paper sets out the theory while the illustrations and application cases on synthetic and real data are brought together in Part 2
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3D Surface-Related Multiple Modeling
Authors A. Pica, G. Poulain, B. David, M. Magesan, S. Baldock, T. Weisser, P. Hugonnet and P. HerrmannA028 3D Surface-Related Multiple Modeling Abstract 1 A. PICA G. POULAIN B. DAVID M. MAGESAN S. BALDOCK T. WEISSER P. HUGONNET AND Data-driven SRME techniques do not require any a priori knowledge of the subsurface (reflectivity structures and velocities). However these methods require a shot location at each receiver location wherein lies the main difficulty for their 3D implementation. Today solutions involve reconstruction of the missing data or reconstruction of the missing multiple contributions. In the following we present a model-based surface-related multiple modeling technique (SRMM) free from any constraint relating to the shot position (including OBC) and distribution. Introduction:
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Fast 3D Wave-Equation Prediction of Multiples
More LessA029 Fast 3D wave-equation prediction of multiples 1 Summary. We present a new efficient wave-equation scheme for prediction and subtraction of water-layer multiples and peg-legs from locally 1D sea-floor with an arbitrary 3D structure below it. The method is suitable for the majority of data from the North Sea. For current quasi-3D marine acquisition with poor sampling between shots in the crossline direction the method is accurate for receiver-side prediction but approximate for source-side prediction. The prediction and adaptive subtraction of multiples are performed in the same domain therefore no additional sorting or additional transformations are required. All source-side and
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3D SRME Practice for Better Imaging
Authors D. Lin, J. Young, W.-J. Lin, M. Griffiths and M. HartmannA030 Z-99 3D SRME Practice for Better Imaging Summary 1 DECHUN LIN JERRY YOUNG WEN-JACK LIN MALCOLM GRIFFITHS MONICA HARTMANN Veritas DGC 10300 Town Park Houston TX 77072 USA Proper parameter selection is key to the success of 3D SRME. The major parameters include surface grid size and crossline aperture. We show that SRME crossline gathers can be used to determine both parameters. We also use a data example from Gulf of Mexico (GOM) to demonstrate the benefits of 3D SRME. Introduction In a marine environment strong contamination from surface multiples is one of the major problems in imaging sub-surface
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A Comparison of Sparse Inversion Techniques for 3D SRME
Authors M. Schonewille Inc., R. Hegge and R. van BorselenA031 A comparison of sparse inversion techniques for 3D SRME Abstract 1 MICHEL SCHONEWILLE ROB HEGGE AND ROALD VAN BORSELEN PGS Court Halfway Green Walton-on-Thames Surrey KT12 1RS UK In 3D surface related multiple elimination shot-gathers are convolved with receiver gathers to obtain multiple contribution traces which in principle can be summed over the inline and cross-line direction to obtain a predicted multiple trace. With current acquisition geometries the sampling in the cross-line direction is sparse which leads to aliasing artifacts when this summation is carried out. It has been proposed to use a sparse inversion over hyperbolic or parabolic
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Multiple Diffractions and Coherent Noise in Marine Seismic Data
Authors N. Hargreaves and R. WombellA032 Multiple diffractions and coherent noise in marine seismic data Abstract 1 The kinematics of both the primaries and the multiples (multiple diffractions) from sea-floor scatterers have similar characteristics when the sea floor is reasonably smooth and has only isolated irregularities. The multiple diffractions like the primary scattering are organised in mid-point gathers in such a way that mid-point stacking can enhance portions of the multiple. Also like the primary scattering the multiples can be distinguished from primary reflection events in the data by their dip in pre-stack shot and receiver gathers. Pre-stack dip-filtering in those domains can be used
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Multichannel Near-Surface Corrections
Authors X. Campman and G.C. HermanA033 0-000 MULTICHANNEL NEAR-SURFACE CORRECTIONS XANDER CAMPMAN 1 and GÉRARD HERMAN 2 1 1 Department of Applied Mathematics Delft University of Technology P.O. Box 5031 2600 GA Delft The Netherlands 2 Shell International E&P Summary The near subsurface can give rise to variations in travel times and amplitudes of upcoming reflections and strong scattered surface waves obscuring reflections. Near-receiver scattered noise can be considered a combination of these problems. On an intra-array scale near-receiver scattered noise can be tracked along a few traces. This implies that it can be suppressed using a deterministic method. We have developed such a method;
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Forward and Inverse Scattering of Surface Waves
Authors A. Kaslilar, C.D. Riyanti, X. Campman and G.C. HermanA034 0-000 FORWARD AND INVERSE SCATTERING OF SURFACE WAVES Summary A. KASLILAR 1 C.D.RIYANTI 1 X.CAMPMAN 1 and G.C. HERMAN 2 1 Institute of Applied Mathematics Delft University of Technology P.O. Box 5031 2600 GA Delft The Netherlands. 2 Shell E&P The Netherlands. Surface waves can be used for imaging near surface layers since they are sensitive to near surface heterogeneities. We developed a method for imaging shallow subsurface heterogeneities and estimating their density contrast using scattered surface waves. We consider 3D elastodynamic scattering by heterogeneities in a laterally invariant layered embedding. We represent the scattered wavefield as a domain
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Estimation of Complex Near Surface Focusing Operators by Global Optimization
Authors D.J. Verschuur and B. El MarhfoulA035 Z-99 Estimation of complex near surface focusing operators by global optimization Abstract 1 Near surface anomalies can severely degrade the data quality and conventional single trace statics do not always correct for these effects sufficiently. Through a model-independent focusing operator estimation procedure based on the CFP technology the data can be redatumed to a level underneath the near surface. However the current procedure is still laborintensive as travel time errors need be picked or tracked in the involved DTS-panels. Therefore under the assumption of a low-order surface-consistent parameterization of the near surface focusing operators the method of finding the
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Sparse 3D Data Kirchhoff Redatuming
Authors S. Tegtmeier, D.J. Verschuur and A. GisolfA036 Abstract SPARSE 3D DATA KIRCHHOFF REDATUMING S. TEGTMEIER D.J. VERSCHUUR and A. GISOLF Delft University of Technology Lab. of Acoustic Imaging and Sound Control PO Box 5046 2600 GA Delft The Netherlands By including a redatuming step in the seismic processing stream the results of the processing can be improved considerably. Due to an increasing amount of 3D data it becomes more and more important to develop a feasible method for the redatuming of 3D prestack data. Common 3D acquisition designs produce relatively sparse data sets which cannot be redatumed successfully by applying conventional wave-equation redatuming. We present a
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Multidimensional Filtering of Irregularly Sampled Seismic Data
More LessA037 Z-99 MULTIDIMENSIONAL FILTERING OF IRREGULARLY SAMPLED SEISMIC DATA Abstract 1 In this paper we introduce a new technique for multidimensional filtering of irregularly sampled seismic data. In this context filtering may be used for coherent noise and interference attenuation as well as the generation of seismic images. The filtering operation consists of the convolution of the filter operator with the seismic data. The filter operator is usually computed on a regular grid (rectangular or hexagonal) that corresponds to the nominal sampling of the seismic data. Unfortunately in the physical world the seismic data are often sampled at irregular spatial
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Recovering Dense and Regularly Sampled 5-D Seismic Data from Current Land Acquisition
Authors S. Xu, Y. Zhang and G. LambaréA038 Z-99 Recovering dense and regularly sampled 5-D seismic data from current land acquisition Abstract 1 SHENG XU 1 * YU ZHANG 1 GILLES LAMBARÉ 2 1 Veritas DGC 10300 town park Drive Houston Texas 77072 USA 2 Ecole des Mines de Paris 35 Rue St. Honoré Fontainbleau 77305 France Ideal 3-D land seismic data processing requires a dense five-dimensional dataset though the current land acquisitions only involve sparse line spacing for both shot lines and receiver lines. Limited by the field conditions even the sparsely sampled seismic data cannot be acquired on a regular grid. Therefore an effective regularization
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Seismic Data Reconstruction Using the Pyramid Transform
Authors B. Hung, C. Notfors and S. RonenZ-99 SEISMIC DATA RECONSTRUCTION USING THE A039 Abstract 1 We present a new method for seismic data regularization using the pyramid transform. By exploiting the property that prediction error filters are frequency-independent in the pyramid domain we can use them as numerical regularization operators to constrain the forward modeling operator that maps the model space to the data space within the context of an inversion. The data can then be reconstructed by transforming the model in the pyramid domain back to the original (f-x) domain. Using synthetic and field data examples we show that data reconstruction using the pyramid transform
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Robust Curvelet-Domain Data Continuation with Sparseness Constraints
More LessA040 4248 ROBUST CURVELET-DOMAIN DATA CONTINUATION WITH SPARSENESS CONSTRAINTS Abstract FELIX J. HERRMANN Department of Earth and Ocean Sciences University of British Columbia Vancouver BC Canada A robust data interpolation method using curvelets frames is presented. The advantage of this method is that curvelets arguably provide an optimal sparse representation for solutions of wave equations with smooth coefficients. As such curvelets frames circumvent – besides the assumption of caustic-free data – the necessity to make parametric assumptions (e.g. through linear/parabolic Radon or demigration) regarding the shape of events in seismic data. A brief sketch of the theory is provided as
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Regional Model during TAGI Desposition in Berkine Basin (Algeria)
Authors J. Salvadores, C. Rossi, O. Kalin, T. Bartrina, A. Alaminos and J.L. SolanoA042 4628 Regional Model during TAGI deposition in Berkine Basin (Algeria) Introduction 1 The Triassic fluvial reservoir sandstones of the TAGI remain a challenge for the oil industry as one of the main targets in North Africa. Although the milestones to its understanding have been placed in the last two decades (A. Boudjema 1987; Gauthier et al.1995; Scott et al.1997; Echikh 1998; Cochran et al.2000; Acheche et al.2001; C. Rossi et al.2002; Turner et al.2002; Eschard et al.2003) there is still room to debate new insights. Objective AUTHOR(S) J. SALVADORES 1 C. ROSSI 2 O. KÄLIN 2 T. BARTRINA 1
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Tectono-Stratigraphic Evolution and Controls on Volcanics in Early Cretaceous in Hameimat Area, Libya
Authors C.G. Ottesen, W. Heerde and T. WeiheA043 Tectono-Stratigraphic Evolution and Controls on Volcanics in Early Cretaceous in Hameimat Area Libya Abstract 1 CHRISTIAN G. OTTESEN WOLFGANG HEERDE & THOMAS WEIHE [email protected] (Copenhagen) [email protected] & [email protected] (Libya) The study focuses on the Nakhla Tuama and Hamid Fields and associated N- & P-Structures (Fig.1) and it reflects a systematic evaluation of all borehole image logs other openhole logs extensive core material and subsequent comparison with seismic interpretation results. The structural objective was to refine the understanding of structural influence on basin evolution volcanism depositional variability and the influence of later tectonics on reservoir quality. This would provide one
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The Thermal Regime and Petroleum Potential in the Russian Sector of the Bering and Okhotsk Seas
Authors I.A. Lipovetsky and L.E. LevineA044 The Thermal Regime and Petroleum Potential in the Russian sector of the Bering and Okhotsk Seas. Abstract 1 In the Western part of the Bering sea and in the Okhotsk sea development of two rift systems: the Late Mesozoic-Cenozoic and Late Cenozoic. The high petroleum potential of these systems was proven by discovery of many oil/gas fields in the West Pacific rift belt. The connection between thermal regime of sedimentary cover and age of rifting or spreading can be using for divided all sedimentary basins and subbasins into three categories: the oil-gas bearing; potentially oil-gas bearing and non-prospective for
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Geological Modeling of Intrusive Bodies
Authors S.A. Petersen and N. SkjeiA045 Geological modeling of intrusive bodies 1 S.A. PETERSEN N. SKJEI Norsk Hydro PO Box 7190 N-5020 Bergen Norway Summary A method for the construction of geological models is presented which includes the presence of intrusive bodies. The development was triggered by modeling studies of 4D seismic effects of sand intrusions above the Grane oil production field (North Sea). Structurally complex intrusion patterns are easily obtained and at any scale. The method is applicable to most types of intrusive bodies and in a way that allows several physical forward evaluations to be invoked (seismic induction log etc.). Introduction The Grane
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Characterization and Occurrence of Opal-Reflectors
Authors P. Pedersen, T. Throndsen, F.T. Lysell, Å.H. Drotting and T. RautakorpiA046 Characterization and Occurrence of Opal-Reflectors Summary 1 Opal-reflectors are observed worldwide in many sedimentary basins. They may be misinterpreted as direct hydrocarbon indicators or as bottom-simulating-reflectors related to gas hydrates. Currently correct interpretation of such reflectors is a challenge in seismic interpretation of petroleum prospects offshore Mid-Norway. A better understanding of opal-reflectors may improve risk assessment in areas where such reflectors occur. Furthermore an increased understanding of opal-reflectors may provide constraints on depositional environment tectonic models and temperature and maturity simulations. In this study we use well observations seismic interpretation and modelling to highlight opalreflectors to provide a better
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Reservoir Modeling of Sand Injections and Significance to Field Performance – Balder Field, Norwegian North-Sea
Authors A. Hjellbakk, D. Bergslien, N. Briedis, R.E. Hill and G.J. MoirA048 Reservoir modeling of sand injections and significance to field performance: Balder Field Norwegian North-Sea Abstract 1 A.HJELLBAKK¹ D.BERGSLIEN¹ N.BRIEDIS¹ R.E.HILL² and G.J.MOIR³ ¹ExxonMobil Exploration and Production Norway AS PO Box 60 4064 Stavanger; Norway ªExxonMobil Upstream Research Company currently Mobil Producing Nigeria Unlimited ³ExxonMobil Upstream Research Company currently retired/consultant The Balder Field started production in 1999 and is producing from seven oil accumulations in three stratigraphic intervals of Paleocene to early Eocene age. The reservoirs are deep-water gravity flow deposited sands draped and sealed by hemipelagic mud and volcanic tuff. Initial reservoir compartmentalization was modified by post-depositional sand remobilization
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Integrated Approach to Acquisition Geometry Analysis
Authors E.J. van Veldhuizen and G. BlacquièreB001 Z-99 Integrated approach to acquisition geometry Abstract 1 analysis E.J. VAN VELDHUIZEN 1 and G. BLACQUIÈRE 2 1 Delft University of Technology Acoustic Imaging and Sound Control PO Box 5046 NL-2600 GA The Netherlands EAGE 67 th Conference & Exhibition — Madrid Spain 13 - 16 June 2005 2 TNO Delft The Netherlands From a subsurface image that is obtained from seismic data after data processing it should be possible to retrieve information about the properties of the subsurface target. However the image can be biased by the acquisition geometry: it contains an acquisition footprint which can obstruct the
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Efficient Software Tools and Methodologies to Optimize Marine Survey Planning
By A. JakobsenZ-99 EFFICIENT SOFTWARE TOOLS AND METHODOLOGIES TO OPTIMIZE MARINE SURVEY PLANNING B002 Summary 1 The optimisation of survey parameters can be an overwhelming effort without having efficient software tools to explore alternative survey and vessel configurations for a given Earth model. A significant effort has been invested to develop integrated survey planning tools that allow the evaluation of seismic data quality after the processing steps. Key elements are the automation of the modelling workflow exchangeable modelling components as well as automated processing algorithms within a common framework. In this paper we describe these integrated and customized tools and present methodologies
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Acquisition Design of the First 4 Component 3D Ocean Bottom Seismic in the Caspian
Authors J. Bouska, T. Lyon, R. Johnston, D. Bddery, D. Howe, M. Mueller, L. Thomsen and D. EbromB003 Acquisition Design of the First 4 Component 3D Ocean Bottom Seismic in the Caspian Summary 1 The signal to noise problems inherent in towed streamer data associated with mud volcanoes subsurface heterogeneities and distributed gas in the Azeri and Gunashli structures of the Caspian sea prompted the use of three dimensional four component ocean bottom seismic (3D/4C OBS) to improve imaging. The introduction of several innovative enhancements to the traditional ocean bottom cable technique when applied cohesively across both acquisition and processing resulted in cost savings compared to conventional OBS acquisition and improved final data quality compared to towed
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Increasing Ray – Path Density in Land Seismic Acquisition – The Source Problem
Authors J. Meunier and T. BianchiB004 Z-99 Increasing Ray-path Density in Land Seismic Acquisition – The Source Problem. Abstract 1 JULIEN MEUNIER* AND THOMAS BIANCHI Compagnie Générale de Géophysique 1 rue Léon Migaux 91341 Massy France For a wide range of reasons such as illumination surface multiple and surface noise reduction increases in source and receiver density are required in land seismic operations. From an economic point of view an increase in receiver density requires extra investment extra labor and a high shooting rate while an increase in source density mainly requires only high shooting rate. From a technical point of view a significant increase
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Cascaded Sweeps – A Method to Improve Vibroseis Acquisition Efficiency – A Field Test
Authors N. Moldoveanu, F. Ortigosa, M. Benabentos, P. Munoz and B. SlopeyB005 Cascaded sweeps- a method to improve vibroseis acquisition efficiency: A field test Summary 1 One of the techniques introduced in the last decade to address the improvement in productivity for vibroseis land acquisition was the cascaded sweep method (Andersen 1995 Moerig and all 2001). In the summer of 2004 Repsol-YPF and WesternGeco performed a field experiment in the Reynosa- Monterrey block Mexico to determine if the use of cascaded sweep method could be beneficial for the seismic exploration program planned for this block. The purpose of this paper is to present the results of this field experiment. Introduction FRANCISCO
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Detection of Inconsistent Coupling in Point-Receiver Land Seismic Data
Authors C. Bagaini and C. Barajas-OlaldeB006 Z-99 Detection of inconsistent coupling in pointreceiver land seismic data Abstract 1 The digitization of the signals recorded by individual geophones in onshore seismic acquisition gives rise to the opportunity to address a phenomenon well known but impossible to effectively tackle using geophone arrays: inconsistent coupling conditions. We present a method for addressing this long-standing problem and apply it to the data acquired during a field experiment with controlled coupling conditions. Introduction It has been recognized for some time that the motion of a geophone case resting on the earth’s surface is not the same as the motion of
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Towards the Low Frequencies– Equipments and Applications
By D. MougenotB007 TOWARDS THE LOW FREQUENCIES: EQUIPMENTS AND APPLICATIONS 1 Summary New acquisition equipment is described that makes it possible to emit and receive low frequencies (below 10 Hz). This includes: for land heavy vibrators and digital accelerometers; for marine high pressure air gun clusters. The primary interest of recording low frequencies is to improve vertical resolution of surface seismic by widening the frequency spectrum. Enrichment of the reflected signal by lower frequencies is also critical for exploration of deep targets for converted wave recording and for post-stack amplitude inversion. Introduction A large improvement in the vertical resolution of surface seismic
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The SOS Source – A Method and Arrangement for a 4D Seismic Source
By O.E. NaessB008 The SOS Source: A Method and Arrangement for a 4D Seismic Source Summary 1 A novel marine seismic source has been developed. This has the ability to remain laterally closer to the pre-plotted line than currently existing sources. It is therefore ideal for 4D surveys. Application of the method and arrangement for a 4D source was first simulated on a full reservoir monitoring seismic survey. Field tests were performed during the 2004 Norne 4D survey in the Norwegian Sea. Results have been analyzed. It appears that the new source is a viable and practical solution. There is a Statoil
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Shear-Wave Anisotropy from Far Offset VSP
Authors R. Zhou, X. Zhao and D.J. DushmanB017 Z-99 SHEAR-WAVE ANISOTROPY FROM FAR Abstract 1 Two types of shear waves have been recorded from a land VSP survey at zero and far offset locations with a vertical Vibroseis source. The two shear waves polarized normal to the compressional waves traveled at different velocities indicative of possible shear-wave splitting. Shear-wave anisotropic parameter γ was estimated from the traveltime data which ranges mostly from 6 to 15%. These results show that zero and offset VSP data can be used to detect and evaluate formation anisotropy. Introduction OFFSET VSP RAN ZHOU XIAOMIN ZHAO AND DAVID J. DUSHMAN VSFusion 16430 Park
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Birefringence Analysis Using Simulated Annealing
Authors H. Dariu, P.Y. Granger and R.J. GarottaB018 Z-99 Birefringence analysis using simulated Abstract 1 By using PS-wave multi-component seismic data it is possible to obtain robust estimates of several subsurface parameters. A global optimization algorithm is proposed to automatically estimate highresolution birefringence (splitting) attributes versus depth. Estimated quantities such as the natural direction of the fast S-wave and the time lag between the fast and slow S-waves can be directly related to fracture orientation and their density. Birefringence effects of the overburden must be determined and removed prior to estimation of the fracture properties at target horizons. Tests of this global optimization method on synthetic and
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A Complex SVD-Polarization Filter for Ground Roll Attenuation on Multi-Component Data
Authors K. de Meersman and R. KendallB019 A complex SVD-polarization filter for ground roll attenuation on multi-component data Summary 1 By their very nature multi-component (3C/9C) datasets provide information on the full wavefield and therefore offer new full wave-field solutions for the ground roll problem. Here we introduce a time-domain 3C complex SVD (Singular Value Decomposition) polarization filter that is optimized to remove most ground roll energy whilst preserving the reflected energy. A 3C Eastern European dataset is used to test filter performance on shot gathers. Finally vertical-component stacks from two polarization filters with different design length are compared to a control stack with no ground
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Ground Roll Detection and Attenuation by 3C Polarization Analysis
More LessB020 Ground roll detection and attenuation by 3C polarization analysis Abstract 1 Ground roll is one of the most troublesome noises of land data and its elimination is often a challenge. Three-component (3C) seismic recording offers techniques to suppress it by exploiting its elliptical polarization nature. We present a flexible method that detects and subsequently removes the ground roll using polarization analysis. The polarization analysis is carried out by doing singular value decomposition (SVD) of the matrix formed by a sliding time window (data-adaptive) of every singlestation 3C recording. We derive a new attribute from the singular values of the
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Comparison of Multi-Component Data from Different MEMS Sensors
Authors S. Ronen, J. Gibson, R. Burnett, J. Roy, B. Montgomery, R. Kendall, L. Comeaux and H. WattB021 Comparison of multi-component data from different MEMS sensors Abstract 1 At least two types of three component (3C) sensors based on Micro-Electro Mechanical Systems (MEMS) technology have become available. We acquired and processed multicomponent data with the two different systems over the same area. Although the two MEMS sensors employ different designs differences between the processed datasets are small. In this paper we present the results. Introduction Land multicomponent seismology is a growing business since the introduction of single sensor 3C receivers deployed in shallow drilled holes. Such single sensor receivers have improved the data quality and have also
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Multi-Component Ocean Bottom Seismic Data Acquired with an Autonomous Node System
Authors P. Docherty, D. Hays, R. Shurtleff and J. PaffenholzB022 Multi-component Ocean Bottom Seismic Data Acquired with an Autonomous Node System Abstract 1 Multi-component ocean bottom seismic (OBS) data for oil and gas exploration have traditionally been acquired with systems in which many seismometers are physically linked with a cable. An alternative approach is to record data utilizing a set of distributed nodes each operating autonomously. In such a system each node marks time and records the sensor outputs continuously for the duration of its deployment on the seafloor which may be days or weeks. The high degree of flexibility in the receiver geometry permitted by a node based
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Imaging Sihil with Full Azimuth Ocean Bottom 4C Node Data
Authors M. Vázquez Garcia, G. Garcia, F. Maya, C.F. Ruiz Torres, E.W. Berg, C. Vuillermoz and A. Fyhn1 B023 IMAGING SIHIL WITH FULL AZIMUTH OCEAN BOTTOM 4C NODE DATA Marco Vázquez Garcia¹ Francisco Maya² Carlos Federico Ruiz Torres² Eivind W. Berg³ Claude Vuillermoz³ Atle Fyhn³ ¹Pemex CNPS Villahermosa ²Pemex Exploración y Producción Región Marina Noreste Ciudad del Carmen Mexico ³SeaBed Geophysical Trondheim Norway. Summary A large 4C OBS seismic program was acquired for Pemex over the Cantarell field offshore Mexico to improve the structural definition of the deeper Sihil field underlying the giant Akal field. The acquisition was made using autonomous receivers planted with accurate positioning on a regular grid in the seabed. The data is acquired
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Vp/Vs Ratios through Multicomponent Velocity Analysis
Authors E. Stucchi, A. Grandi and A. MazzottiB024 Z-99 Vp/Vs Ratios through Multicomponent Velocity Abstract 1 A key step in the multicomponent data processing is the computation of the Vp/Vs ratios. In this paper we show that a multicomponent velocity analysis can combine information from horizontal and vertical components into a single panel and can therefore improve the accuracy of the velocity estimate. In addition a multicomponent velocity analysis followed by Common Conversion Points binning can indicate the Vp/Vs ratios that produce the optimum focusing of the coherence panel in the case of dipping reflectors. The multicomponent panel in which the velocity analysis is performed is obtained
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A Southern North Sea Multi-Survey PreSDM
Authors I.F. Jones, A.G. Campbell, E. Evans, D. Judd and S. ElamB025 A Southern North Sea Multi-Survey preSDM 1 A. G. CAMPBELL 1 E.EVANS 2 .D.JUDD 2 I. F.JONES 2 S.ELAM 1 Abstract Exploration in the Southern North Sea using conventional imaging techniques is hampered by complexities in the Mesozoic overburden and the Zechstein evaporites with dolomitic rafting overlying potential targets. 3D preSDM imaging has come into widespread use in recent years in an attempt to resolve such problems. Here we present case history from the ConocoPhillips acreage over block 49/14a where a four survey merge covering some 430sq.km (figure 1) was reprocessed to yield a coherent single input volume for
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Application of Pre-Stack Wave Equation Depth Migration in North West Europe
Authors S. Pharez, N. Jones, S. Zimine, H. Prigent, K. Ibbotson and J.-P. GruffeilleB026 Application of Pre-stack Wave Equation Depth Migration in North West Europe Introduction 1 Travel-time based PreSDM methods are known to only image only part of the wavefront in the presence of high velocity layers or complex/rugose structure. For such environments in the Gulf of Mexico and more recently offshore Angola wave equation PreSDM has proven to be beneficial yielding significantly improved imaging. The technique has also been applied in the North Sea and North West Europe. We present and discuss case studies from the latter comparing and contrasting our observations with results from standard 3D Kirchhoff PreSDM. Method The
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Wave Equation Migration and Illumination on a 3-D GOM Deep Water Dataset
Authors B. Fontechha, W. Cai, F. Ortigosa, Q. Liao and S. JinB027 Wave equation migration and illumination on a 3-D GOM deep water dataset 1 BRIGIDA FONTECHHA WENYING CAI FRANCISCO ORTIGOSA QINGBO LIAO 1 AND SHENGWEN JIN 2 1 Repsol YPF The Woodlands Texas USA 2 Screen Imaging Technology Inc. Houston Texas USA Summary The generalized screen propagator (GSP) is a one-way wave equation based wide-angle propagator. The dual domain implementation of GSP migration provides a fast and accurate 3-D wavefield extrapolation and produces high-resolution and high-fidelity subsalt images. This migration technology was applied to a 3-D GOM deep water dataset and was compared with Kirchhoff PSDM. A wave equation illumination
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Comprehension and Evaluation of PSDM Algorithms for Subsalt Imaging
Authors Q. Liao, B. Fontecha, W. Cai and F. OrtigosaB028 Comprehension and Evaluation of PSDM Algorithms for Subsalt Imaging Abstract 1 As pre-stack depth migration becomes a routine process in hydrocarbon exploration of subsalt areas of the Gulf of Mexico poor subsalt images obtained by conventional Kirchhoff migration become industry’s major concern and various wave equation migration implementations are introduced to improve subsalt images. We present a simple and effective method to examine Kirchhoff and wave equation operators through study of migration impulse responses and analysis of forward wavefield propagation using the Sigsbee2A model. The single value wavefront approximation of Kirchhoff migration fails in subsalt areas of complex geology
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Deepwater Imaging beneath Gas Anomalies – A Case Study
Authors O. Khan, U. Klein-Helmkamp and T. ChapmanB029 Deepwater imaging beneath gas anomalies – a case study. Abstract 1 Seismic structural imaging for the target reservoir at the ‘Kikeh’ Oil Field offshore Malaysia is severely affected by the presence of shallow gas anomalies. Conventional pre-stack time migration (PreSTM) cannot handle the lateral velocity variations introduced by these anomalies; the gas introduces sufficient velocity contrast to cause deterioration of the image and pronounced ‘sags’ in the depth-converted seismic data. This poses problems for interpretation as well as reserve estimation. We used a processing flow incorporating detailed velocity modeling and isotropic pre-stack depth migration (PreSDM) to alleviate this problem.
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Prestack Depth Migration of Dual-Azimuth Surveys Incorporating Azimuthal P-Wave Anisotropy
Authors P. Whitfield, F. Dewey and M. KingB030 Prestack Depth Migration of Dual-Azimuth Surveys incorporating Azimuthal P-wave Anisotropy Abstract 1 It is standard practice now to build velocity models for prestack depth migration that include polar anisotropy (vertical or tilted transverse isotropy “VTI” or “TTI”). In this paper we discuss a dualazimuth North Sea dataset that exhibits significant azimuthal anisotropy as well as polar anisotropy. We present a practical production workflow using innovative analysis techniques (“butterfly gathers”) and solve for the azimuthal anisotropy using two sets of anisotropic parameters with a single velocity field taking advantage of the fact that we are dealing with only two dominant
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Hild, Multi Azimuth Seismic Experiment
Authors A. Riou, K. Kravik, P. Sexton, L. Lemaistre, V. Aubin and F. BertiniZ-99 HILD MULTI AZIMUTH SEISMIC EXPERIMENT B031 Abstract 1 K. KRAVIK 1 P. SEXTON 2 L. LEMAISTRE 2 V. AUBIN 2 A. RIOU 2 and F. BERTINI 1 1 TOTAL E&P NORGE AS Geosciences Division PO Box 168 4001 Stavanger Norway 2 TOTAL E&P France Seismic imaging is a major challenge over the Hild discoveries in blocks 29/6 9 30/4 and 7 offshore Norway due to the compartmentalisation of the reservoir section and presence of a gas dis-migration in the overlaying Cretaceous series. The original 3D survey covering Hild has been reprocessed to try to improve the quality of the
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Improving Seismic Imaging Using Global Offset, Geo-Electric and Electromagnetic Methods
More LessB032 Improving seismic imaging using global offset geo-electric and electromagnetic methods 1 Introduction In many complex geological settings imaging accurately the shallow sedimentary sequences is a key step in order to interpret properly also the deeper part of the seismic sections. In fact processing work-flows that are not focused in solving imaging problems in the shallow part of the data (first 300-500ms) can prevent a satisfactory imaging also at target depth. That is the case when the presence of shallow high-velocity layers and near surface geological complexity can cause sharp lateral and vertical velocity variations. Due to the low signal
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Integrated Pore-Pressure Prediction Using High-Resolution Seismic Velocity and Rock Physics
Authors J. Khazanehdari, N. Dutta, M. Portet and R. BachrachB033 Integrated pore-pressure prediction using highresolution seismic velocity and rock physics Abstract 1 The present seismic-based geopressure techniques use calibrated seismic velocity to pressure as a means of estimating background shale pressure. These methods lack the necessary highresolution velocity and pressure information required for drilling proposes. A fully integrated seismic pore-pressure prediction (iPPP) that can be used for drilling requires important elements such as high-resolution velocity a rock-physics-based pressurevelocity model and a sound understanding of lithology structure and fluid types. This paper describes a practical workflow that uses both seismic inversion and velocity analysis to obtain a high-resolution seismic velocity.
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Real Time Update of 3D Velocity Model for Steering Wells on Seismic Data
Authors F. Pivot, F. Bertini, F. Mansanne, G. Morin and N. KeskesB034 Real time update of 3D velocity model for steering wells on seismic data Abstract 1 Quality enhancement of seismic data allows to build seismic attributes (like lithoseismic cubes) that are precious for predicting encountered geology during the drilling of the well. However these data are often poorly used because all drilling operations are conducted in depth while seismic data are in two-way time. Of course it is possible to apply time to depth conversion in order to obtain seismic information in depth. However during the drilling phase the time-depth conversion mismatches rapidly. We propose here a strategy suited for
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The 2004 BP Velocity Benchmark
Authors F.J. Billette and S. Brandsberg-DahlB035 The 2004 BP Velocity Benchmark Abstract 1 In 2004 BP conducted a 2D velocity model estimation benchmark study. The study was open to all interested parties and was constructed as a blind test of available velocity model estimation/building techniques. The test was based on a 2D synthetic (finite-difference) dataset generated by BP which was made available to the interested parties. After receiving the data the participating groups were offered to present their results at the 2004 EAGE workshop and/or provide the results to BP to partake in the overall evaluation. In this paper we will present the model used
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New Quality Metric for Validation of Velocity Models
Authors F. Ljones, M. Nickel, G.G. Borgos, L. Sonneland and R. MjeldeB036 Abstract 1 The crucial analysis step in seismic processing is to establish an optimal velocity model. The quality of the velocity model has a major influence on the quality of the final processing result. The quality of the velocity model can be measured by how well the velocities NMOcorrect the common reflection-point gathers (CRP). However after transformation of the CRP-gathers to zero offset it is impossible to validate the quality of the velocity model without invoking the prestack CRP-gathers. It is prohibitive to pass an undecimated prestack seismic data volume to the interpretation stage. As a result of this
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Automatic, Dense and Volumetric Picking for High-Resolution 3D Tomographic Model Building
Authors V. Dirks, B. Wang, D. Epili, D. Wheaton, P. Guillaume and F. AudebertZ-99 Automatic dense and volumetric picking for high-resolution 3D tomographic model building B037 Abstract 1 As survey sizes are steadily increasing 3D tomography as the key component of today’s velocity model building workflows has to be performed on large data volumes within acceptable turnaround times. To provide high-resolution velocity models dense volumetric picking is required. This leads to even larger data volumes. It is therefore paramount to automate as many processing steps as possible to free the time of the geophysicist for the necessary QC. In this paper we present a modified workflow for high-resolution 3D tomography addressing the need
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3D Grid Tomography Based on Focusing Analysis
Authors B. Wang, F. Qin, V. Dirks, P. Guillaume, F. Audebert and D. EpiliZ-99 3D grid tomography based on focusing analysis B038 Abstract 1 We have developed a new 3D grid tomography based on the analysis of focusing errors. The seismic input to this new velocity analysis is a set of migration panels that are stack images formed at various imaging conditions zero-time or non zero-time. By comparing these different common focusing error panels the best focused events and their corresponding focusing errors are picked. The picked focusing errors and associated local reflector attributes (position and dip) are then fed into the existing 3D grid tomography to update the velocity model. This new
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Tomographic Residual Moveout Inversion of PreSTM Common-Image-Gathers
More LessZ-99 Tomographic residual moveout inversion of PreSTM common-image-gathers B039 Abstract 1 We present a new tomographic inversion technique for 3D anisotropic velocity-depth model building which inverts the residual moveout in PreSTM image gathers in a horizon consistent manner using the interpretations in the corresponding time migrated image. Our experience shows that tomographic inversion of PreSTM residual moveout provides velocity-depth models that require only small final updates via PreSDM residual moveout inversion in case of moderately complex structures. Since tomography after PreSTM uses time domain data it allows full non-linear inversion which shortens considerably the PreSDM cycle on industrial projects. Another
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3-D Inversion with Kinematic Wavefield Attributes
By N.-A. MüllerB040 0-00 3-D INVERSION WITH KINEMATIC WAVEFIELD ATTRIBUTES N.-A. Müller Geophysical Institute University of Karlsruhe Hertzstr. 16 76187 Karlsruhe Germany Summary. The 3-D Common-Reflection-Surface (CRS) stack provides an entire set of kinematic wavefield attributes which may be used for Dix-type inversion algorithms. These methods iteratively evaluate velocity models of the subsurface starting from the measurement surface. In general the models obtained are characterized by blocks of constant velocities separated by smooth first-order interfaces. Due to the iterative nature of this methods implementations suffer from error accumulation with increasing number of interfaces. In order to avoid this problem the Dix-type method
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Pore- to Field-Scale Multi-Phase Upscaling for IOR (SPE94191)
Authors T.R. Lerdahl, A.B. Rustad, T.G. Theting, J.Å. Stensen, P.E. Øren, S. Bakke, T. Boassen and B. PalatnikSPE 94191 Pore- to Field-Scale Multi-Phase Upscaling for IOR T.R. Lerdahl SPE A.B. Rustad SPE T.G. Theting SPE J.Å. Stensen SPE P.E. Øren SPE S. Bakke SPE T. Boassen SPE and B. Palatnik SPE Statoil Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and
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Improved Fluid Characterization for Miscible Gas Floods (SPE94034)
Authors A.M. Egwuenu, R.T. Johns and Y. LiSPE 94034 Improved Fluid Characterization for Miscible Gas Floods A.M. Egwuenu R.T. Johns and Y. Li SPE The U. of Texas at Austin Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material as presented does
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Effect of Geologic Parameters on CO2 Storage in Deep Saline Aquifers (SPE93952)
Authors S. Mo, P. Zwiegel, E. Lindeberg and I. AkervollSPE 93952 Effect of Geologic Parameters on CO2 Storage in Deep Saline Aquifers S. Mo SPE P. Zweigel E. Lindeberg SPE and I. Akervoll SPE SINTEF Petroleum Research Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s).
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The Impact of Pertinent Parameters on the Design of Hydraulic Fracturing in Gas Condensate Reservoirs (SPE94074)
Authors G.A. Carvajal, A. Danesh, M. Jamiolahmady and M. SohrabiSPE 94074 The Impact of Pertinent Parameters on the Design of Hydraulic Fracturing in Gas Condensate Reservoirs G.A. Carvajal A. Danesh M. Jamiolahmady and M. Sohrabi Petroleum Engineering Inst. Heriot-Watt U. Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction
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Productivity Assessment of Fractured and Non-Fractured Wells in a Lean/Intermediate Low Permeability Gas Condensate Reservoir (SPE93136)
Authors T. Baig, U. Droegemueller and A.C. GringartenSPE 93136 Productivity Assessment of Fractured and Non-Fractured Wells in a Lean/Intermediate Low Permeability Gas Condensate Reservoir T. Baig and U. Droegemueller Wintershall AG and A.C. Gringarten Imperial College London Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by
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Integrating Continuous 4D Seismic Data Into Subsurface Workflows
Authors O.I. Barkved, J.H. Kommedal, T.G. Kristiansen, K. Buer, R.M. Kjelstadli, N. Haller, M. Ackers, G. Sund and R. BakkeC001 Integrating Continuous 4D Seismic Data Into Subsurface Workflows Summary 1 In the period from October 2003 to November 2004 four seismic surveys have been acquired across the permanently installed seismic array (LoFS) at the Valhall Field Offshore Norway [1]. The installation followed the demonstration of significant production induced 4D seismic response when matching a marine streamer 4D survey acquired in 2002 to a survey acquired in 1992 [2]. Capturing the value of the continuous 4D seismic monitoring scheme implemented at Valhall is contingent on multidisciplinary integration of the 4D seismic products with other subsurface data. The potential and limitations
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Reservoir Management of the Njord Field (SPE92419)
Authors S. Talukdar and L.H. BrusdalSPE 92419 Reservoir Management of the Njord Field S. Talukdar SPE and L.H. Brusdal SPE Hydro Oil and Energy Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material as presented does not necessarily reflect any
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History Matching Using 4D Seismic and Pressure Data on the Norne Field
Authors M. Lygren, O. Husby, B. Osdal, Y. El Ouair and M. SpringerC003 HISTORY MATCHING USING 4D SEISMIC AND PRESSURE DATA ON THE NORNE FIELD Abstract 1 The Norne reservoir simulation model was history matched to time-lapse seismic data (acoustic impedance) and downhole pressure data (RFT) using the method of computerassisted history matching. The mismatch of the reservoir simulator was reduced compared to history matching of well data only. This led to an increased understanding of the flow in the reservoir and to increased confidence in the 4D interpretations which are important input to the well-planning at Norne. Introduction The Norne Field is situated in the southern part of the Nordland II
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The Geochoke Well Test Response in a Catalogue of Systematic Geotype Curves (SPE93992)
Authors P.W.M. Corbett, Y. Ellabad, J.I.K. Egbert and S. ZhengSPE 93992 The Geochoke Well Test Response in a Catalogue of Systematic Geotype Curves P.W.M. Corbett SPE Y. Ellabad 1 J.I.K. Egert 2 and S. Zheng SPE Heriot-Watt U. Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the
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Reservoir Monitoring with Pulsed Neutron Capture Logs (SPE94199)
Authors C. Morris, T. Aswad, F. Morris and T. QuinlanSPE 94199 Reservoir Monitoring with Pulsed Neutron Capture Logs C. Morris SPE Schlumberger T. Aswad SPE BP America Inc. and F. Morris and T. Quinlan SPE Schlumberger-PTC Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The
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Fracture Mapping Using Microseismic Monitoring Data Recorded from Treatment Well – Results Based on 20 Hydro-Fracturing Jobs
Authors E. Gaucher, C. Maisons, E. Fortier and P. KaiserC008 Z-99 Fracture mapping using microseismic monitoring data recorded from treatment well – Results based on 20 hydro-fracturing jobs Abstract 1 To stimulate their oil recovery oil companies carry out hydraulic fracturing jobs for which the fracture characterization as fluid path is crucial. Microseismic monitoring of such experiments is used for fracture mapping; nevertheless monitoring from treatment well is still a challenge. Over these last five years using the field experience gained over 20 jobs we managed to collect a significant database/catalogue of frac jobs results monitored from the injection well (treatment well). Various configurations of the tools in the
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Estimation of Horizontal Permeability Using Pressure Changes Derived from 4D Seismic Data
Authors M. Floricich, Y. Almaskeri and C. MacBethC009 Z-99 Estimation of horizontal permeability using pressure changes derived from 4D seismic data Abstract 1 MARIANO FLORICICH* YAHYA ALMASKERI AND COLIN MACBETH Institute of Petroleum Engineering Heriot-Watt University Edinburgh UK EH14 4AS There are now several methods available for delivering separate estimates of pressure and saturation from time-lapse seismic data. A natural step beyond these procedures is to use the pressure component to estimate horizontal permeability this then being used to constrain the reservoir model. Here tests of this particular extension are performed on synthetic data examples typical of hydrocarbon reservoirs in the North Sea. The results indicate that
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Estimation of Layer Thickness and Velocity Changes Using 4D Prestack Sesimic Data
More LessC010 Estimation of layer thickness and velocity changes using 4D prestack seismic data Abstract 1 0 0 th EAGE 67 Conference & Exhibition — Madrid Spain 13 - 16 June 2005 1 1 1 T.RØSTE A.STOVAS AND M. LANDRØ 1 Dep. Of Petroleum Engineering and Appl. Geophysics NTNU 7491 Trondheim Norway For some hydrocarbon reservoirs severe compaction of the reservoir rocks is observed. This compaction is caused by the production and is often associated with changes also for the overburden. Time-lapse seismic data can be used to monitor this compaction process. Since the compaction causes both changes in layer thickness
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Linking Geomechanics and Seismics – Stress Effects on Time-Lapse Multicomponent Seismic Data
Authors J. Herwanger and S. HorneC011 Linking geomechanics and seismics: Stress effects on time-lapse multicomponent seismic data Abstract 1 Time-lapse stress effects on seismic data can have a similar magnitude as time-lapse effects caused by changes in saturation and pore pressure. Production-induced stress changes occur not only in the reservoir interval itself but are also manifested in the overburden. Furthermore because stress fields caused by reservoir production are directionally dependent the resulting changes in the elastic properties yield an anisotropic seismic response. To study effects in seismic data we have developed a workflow that allows the prediction/estimation of changes in (anisotropic) seismic observations from stress
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Integrating 4D Seismic, Geomechanics and Reservoir Simulation in the Valhall Oil Field
Authors P.J. Hatchell, R.S. Kawar and A.A. SavitskiC012 Integrating 4D seismic geomechanics and reservoir simulation in the Valhall oil field. 1 P.J. HATCHELL R.S. KAWAR AND A.A. SAVITSKI Shell International Exploration and Production Rijswijk The Netherlands Summary Time-lapse seismic monitoring of compacting reservoirs measures changes that occur both inside and outside of the reservoir interval. Inside the reservoir changes in saturation porosity velocity and layer thickness alter the reflection coefficients and intra-reservoir travel times that result in both amplitude and travel time changes. Outside of the reservoir the compaction creates long-wavelength changes in the stress and strain fields that perturb the seismic velocity and produce additional changes
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Investigating the Overburden Effect on Time-Lapse Seismic by Geomechanical Modeling
Authors P.V. Angelov, R. Arts, J. Spetzler and K. WapenaarC013 Z-99 INVESTIGATING THE OVERBURDEN EFFECT ON TIME-LAPSE SEISMIC BY GEOMECHANICAL MODELLING. Introduction PETAR VLADOV ANGELOV 1 ROBARTS 1 2 JESPER SPETZLER 1 and KEES WAPENAAR 1 1 Delft University of Technology Department of Geothechnology Delft The Netherlands 2 TNO Uttrecht The Netherlands In time-lapse seismic experiments it is important to estimate accurately the rock physics parameters at reservoir level. To solve the inverse problem (i.e. invert the rock parameters from the seismic data) additional information is needed. This extra information is obtained by solving the forward problem (e.g. using synthetic reservoir models Angelov et al. 2004). The lack of
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Effect of Navigation Attributes on 4D Seismic Repeatability
Authors C. Lacombe and E. RenouxC014 Effect of Navigation Attributes on 4D Seismic Repeatability Abstract 1 A methodology has been implemented to study the influence of variations in navigation parameters on seismic repeatability for marine 4D surveys. Synthetic seismic traces representative of real acquisition geometry are generated for base and monitor surveys using a wavefront propagation technique. The same velocity-depth model and source characteristics are used to simulate the seismic response of the two data vintages. Consequently all differences observed on synthetics are due to changes in acquisition parameters between base and monitor surveys. We establish statistical relationships between seismic repeatability and changes in acquisition
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Repeatability Monitoring during Marine 4D Streamer Acquisition
More LessC015 Repeatability monitoring during marine 4D streamer acquisition Abstract 1 The quality of 4D seismic data depends partially on the repeatability of source and receiver positions between the baseline and monitor survey. It is therefore important that positioning repeatability requirements are determined at the survey design stage and that they are monitored during acquisition. A software tool has been developed to monitor 4D positioning repeatability during marine acquisition. For each trace of a monitor survey a matching function is used to search for the most similar trace in the baseline dataset. For each pair of matching traces a number of
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Repeatability Using a Permanently Installed Seismic Array
Authors J.H. Kommedal, O.I. Barkved and K. HennebergC016 Repeatability using a permanently installed seismic array Abstract 1 The paper presents an assessment of repeatability of 4D data from a permanently installed seismic array. We compare the geometry of this acquisition with streamer and VSP acquisition and address effects of non-repeatable noise and its impact. Introduction Over the last years 4D seismic has become an increasingly important tool for reservoir management. Consequently a lot of work has been put into trying to develop acquisition technology which will improve our ability to detect production induced seismic changes. One way to achieve a high degree of repeatability of acquisition geometry
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Effects of the Earth Model’s Low Frequency Trend in Time-Lapse Seismic – Some Practical Considerations
Authors M. Verkeyn, A. Sturniolo and F. MelchioriC017 Effects of the Earth model’s low frequency trend in time-lapse seismic: some practical considerations Abstract 1 Time-lapse seismic is becoming a more widely used tool for reservoir monitoring. Apart from qualitative information reservoir engineers are also looking for quantitative information. A classic approach to achieve this goal is to invert the seismic data into acoustic or elastic impedance data and derive properties from those indirect measurements. A problem with this approach is that absolute measurements are needed while the seismic data itself can only provide relative information: the low frequencies are missing. The low frequency component is obtained from
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4-D Stratigraphic Inversion of the Girassol Field – Towards a More Quantitative Approach
Authors Y. Lafet, P. Duboz, B. Deschizeaux, F. Lefeuvre and C. HubansC018 4-D STRATIGRAPHIC INVERSION OF THE GIRASSOL FIELD - TOWARDS A MORE QUANTITATIVE APPROACH Summary 1 As applications of 4-D seismic technology become more mature there is a growing need for quantitative 4-D inversion workflows where base and monitor surveys are jointly inverted to estimate time-lapse changes in elastic properties which are then linked to changes in reservoir pressure and fluid saturation. In practice quantitative 4-D elastic inversion is made difficult by the presence of time-variant misalignments between corresponding seismic reflections in base and monitor surveys. These time-shifts are often the result of production-related velocity changes within the reservoir interval.
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Improving Drainage Interpretation Using a New Bayesian Time-Lapse Inversion
Authors Y. El Ouair, A. Buland, B. Osdal and A.-K. FurreC019 T-11 Improving drainage interpretation using a new Bayesian time-lapse inversion Abstract 1 An inversion technique for time-lapse seismic data has been developed to estimate changes of elastic properties (e.g. P-impedance S-impedance and density) of a reservoir due to production. The new aspects of this method is the direct and simultaneous inversion of prestack seismic difference data in addition to the Bayesian setting formalism applied to timelapse. This method provides posterior uncertainties by combining the a priori information of both the elastic properties changes and the seismic difference data. Until now this inversion has been successfully applied on real post-stack
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Matching of Multiple Time-Lapse Data Using Multi-Coherence Analysis
Authors H. Hoeber, D. Lecerf, H. Zaghouani and D. WhitcombeC020 Matching of multiple time-lapse data using multi-coherence analysis Abstract 1 We show how spectral coherence analysis and the multiple coherence technique can be used to extract reliable signal and noise spectra when more than two vintages of seismic time-lapse data have been recorded. We compare this method to other coherency-based approaches and we discuss matching strategies for multi-vintage seismic data. Introduction Matching is a key technique for time-lapse processing. Matching filters are applied to the seismic data in order to attenuate variations of the signal and to optimise the production related 4D signature. The operators are commonly designed to
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Imaging of Passive Seismic Sources by Reverse Modelling
Authors D. Gajewski and E. TessmerC021 Summary IMAGING OF PASSIVE SEISMIC SOURCES BY REVERSE MODELLING D. GAJEWSKI and E. TESSMER Institute of Geophysics University of Hamburg Germany The passive seismic method for reservoir monitoring and characterisation and monitoring of hydraulically induced fractures is developing into a main stream technology in the oil business. Current techniques rely on the fact that the recorded event is detectable at most of the stations of the recording array. Weak events not visible in the individual seismogram of the array are missed out. We present a new approach where no picking of events in the seismograms of the recording array
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Advanced Microearthquake Analysis Techniques for Reservoir Monitoring
Authors D. Colombo and G.R. FoulgerC022 Abstract 1 MicroEarthQuakes (MEQs) can provide information concerning reservoir structure the migration of fluids and permeability. Production-related pressure gradients generate differential stress conditions in the reservoir that can be monitored by means of MEQ moment tensor solutions which include isotropic components. MEQs can be considered to be distributed seismic sources that occur at depth generate both P and S waves and are able to provide additional information on rock physics by illuminating the reservoir directly from beneath. Robust 3D tomographic methods allow the determination of parameters such as Vp Vs and the Vp/Vs ratio in the reservoir and enable
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Passive Seismic Monitoring Using a Migration Technique
Authors S. Rentsch, S. Buske, S. Lüth and S.A. ShapiroC023 Z-99 Summary PASSIVE SEISMIC MONITORING USING A MIGRATION TECHNIQUE SUSANNE RENTSCH STEFAN BUSKE STEFAN LÜTH and SERGE A. SHAPIRO Institut für Geologische Wissenschaften Fachbereich Geophysik Freie Universität Berlin Malteser Strasse 74-100 12249 Berlin Germany In this paper we present a new approach for location of seismic sources which is based on principles of wave field back-propagation using multicomponent data. The use of migration techniques for imaging of seismic sources has the advantage that precise picking of arrival times is not required. Our approach requires only a preliminary selection of event time intervals and is much less sensitive to this
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Characterization of Induced Seismicity in Petroleum Reservoir – A Case Study
Authors E.K.M. Sze, M.N. Toksoz, D.R. Burns and G.F. MuellerC024 CHARACTERIZATION OF INDUCED SEISMICITY IN PETROLEUM RESERVOIR: A CASE STUDY Abstract 1 Fluid production and injection in hydrocarbon and geothermal reservoirs generally results in induced seismic activity. In this paper we study the microseismic activity in the Yibal Field in Oman. The microearthquake data we used are those collected by a five-station digital network in the Yibal Field between 29 October 1999 and 18 June 2001. We relocated 405 high-quality microseismic events using P and S travel-times picked from waveform data by the global grid-search location method. The results reveal a complex seismic zone with a NE-SW trend. All
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Estimation of Long Term Gas Condensate Well Productivity Using Pressure Transient Data (SPE94065)
Authors R. Osorio, G. Stewart, A. Danesh, D. Therani and M. JamiolahmadySPE 94065 Estimation of Long Term Gas Condensate Well Productivity Using Pressure Transient Data R. Osorio G. Stewart A. Danesh D. Therani and M. Jamiolahmady Inst.of Petroleum Engineering Heriot-Watt U. Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by
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A Semi-Analytic Model for Productivity Testing of Multiple Wells (SPE94153)
Authors P.A. Fokker, G.K. Brouwer, F. Verga and D. FerreroSPE 94153 A Semi-Analytical Model for Productivity Testing of Multiple Wells P.A. Fokker SPE and G.K. Brouwer TNO – NITG and F. Verga SPE and D. Ferrero SPE Politecnico di Torino Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction
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Integrated Workflow for Quantitative Use of Time-Lapse Seismic Data in History Matching – A North Sea Field Case (SPE94453)
Authors M.C. Haverl, M. Aga and E. ReisoSPE 94453 Integrated Workflow for Quantitative Use of Time-Lapse Seismic Data in History Matching: A North Sea Field Case M.C. Haverl M. Aga and E. Reiso Norsk Hydro ASA Copyright 2005 Society of Petroleum Engineers This paper was prepared for presentation at the SPE Europec/EAGE Annual Conference held in Madrid Spain 13-16 June 2005. This paper was selected for presentation by an SPE Program Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper as presented have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the
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