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65th EAGE Conference & Exhibition
- Conference date: 02 Jun 2003 - 05 Jun 2003
- Location: Stavanger, Norway
- Published: 02 June 2003
41 - 60 of 487 results
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University Curricula and Industry Needs
More LessB-02 UNIVERSITY CURRICULA AND INDUSTRIAL NEEDS 1 The talk with consider the issues that must be addressed by university staff when designing geoscience and engineering course curricula. First and foremost we ignore at our peril the simple fact that our customer is the student. Plausible arguments are sometimes presented for a return to basics; more on classical mechanics for example. However the danger of customers voting negatively with their feet is a very real constraint on the balance and content of course curricula. The customer also expects and assumes that her/his employability will have been increased by studying the course
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E-Learning in Geosciences
More LessB-03 MAKING E-LEARNING WORK – EXAMPLES OF PRODUCTS DEVELOPED BY STATOIL AND NORWEGIAN ACADEMIA Abstract 1 Learning used to be synonymous with attending a formal course or a conference. Nowadays we would also include learning-on-demand and informal learning anytime and anywhere hence the popular term “life-long learning”. Among other things this has been made possible by computers the Internet and the emergence of “e-learning” believed by many to be the great new market of the Internet age. In academia e-learning is usually taken to refer to courses available online with content provided in digital format. However a company employee may
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Technical Skill Assessment – Measuring Staff Capabilities and Optimizing Training Investments
Authors J.D. Johnsen and M. LaPrea-BigottB-06 TECHNICAL SKILL ASSESSMENT – MEASURING STAFF CAPABILITIES AND OPTIMIZING TRAINING INVESTMENTS 1 The value of E&P technology applications can only be realized when technical staff has the skills and knowledge to apply the technology. Significant challenges for E&P companies and vendors today are to deliver focused training for staff in relevant technology applications and to understand the breadth depth and location of technical expertise within their companies. An important yet simple tool to help meet these challenges is rigorous skill or competency assessment. Many companies today (e.g. Shell BP) have implemented skill assessment and are using results to add
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Experience with Generalized-Screen Methods in Wave Equation Migration
Authors C. Notfors, Y. Zhang, Y. Xie and G. ZhangB-09 EXPERIENCE WITH GENERALIZED-SCREEN METHODS IN WAVE EQUATION MIGRATION Summary We present a stable least squares optimized generalized-screen (GS) formula for migration. Theoretical analysis and numerical examples show that our GS method has potential to provide high quality wave equation migration results. It removes splitting errors suppresses numerical dispersion and images steeply dipping reflectors. However when large lateral velocity variations are present the required normalization operator appears to degenerate image quality. Hence improving the normalization method or seeking a more stable algorithm is required for its practical use. Introduction Finite-difference migration based on one-way wave extrapolation (Claerbout 1985) automatically handles
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Angle Gathers for Shot-Record Migration by Local Harmonic Decomposition
By R. SoubarasB-10 ANGLE GATHERS FOR SHOT-RECORD MIGRATION BY LOCAL HARMONIC DECOMPOSITION 1 Summary EAGE 65th Conference & Exhibition — Stavanger Norway 2 - 5 June 2003 ROBERT SOUBARAS CGG 1 rue Léon Migaux 91341 Massy France It is now recognized that shot-record wave-equation migration is the best method for imaging in complex media. However it is also recognized that producing one output image is not enough. Velocity analysis can only be done when a gather is produced as well as AVO analysis or multiple attenuation. This paper starts by describing the local harmonic decomposition: it is an efficient algorithm which can
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One Way vs Two Way Wave Equation Imaging – Is Two-Way Worth It?
Authors J.B. Bednar, K. Yoon, C. Shin and L. LinesB-11 ONE WAY VS TWO WAY WAVE EQUATION IMAGING – IS TWO-WAY WORTH IT? 1 KWANGJIN YOON 1 CHANGSOO SHIN 1 J. BEE BEDNAR 2 and LARRY LINES 3 Abstract 1 Seoul National University Seoul Korea 2 Core Laboratories Houston Texas U.S.A. 3 University of Calgary Calgary Alberta Ca Current production-grade-wave-equation migration technology is almost totally based on one-way methods. These methods are typically derived through an asymptotic approximation of the square root of a one-way propagator derived by factoriaztion of some form of wave equation. Primary reasons for the dominance of one-way approaches are most certainly the relative ease
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Beam-Wave Migration
Authors S. Brandsberg-Dahl and J.T. EtgenB-12 BEAM-WAVE MIGRATION Summary 1 We present a hybrid beam/wavefield migration scheme that overcomes the dip limitation in conventional downward continuation schemes. The resulting migration operators are not limited to downward propagating waves only and in contrast to ray tracing methods they contain the full waveform in areas with large/sharp velocity contrasts. Introduction S. BRANDSBERG-DAHL and J. T. ETGEN BP America Inc. 200 Westlake Park Blvd Houston TX 77079 USA Downward continuation wavefield migration has gained in popularity in recent years and has proven to be an accurate and reasonably stable method for imaging seismic data in complex geology. There
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Delayed-Shot 3-D Prestack Depth Migration
Authors J. Sun, Y. Zhang, C. Notfors, S. Gray, L. Chernis and J. YoungB-13 DELAYED-SHOT 3-D PRESTACK DEPTH MIGRATION YU ZHANG 1 JAMES SUN 1 CARL NOTFORS 2 SAM GRAY 3 LEON CHERNIS 1 and JERRY YOUNG 1 1 Veritas DGC Inc. 10300 Town Park Drive Houston TX 77072 USA Summary We present a formulation for delayed-shot migration of marine data in 2-D (plane-wave sources) and in 3-D (linear sources and planar sources). We present speedup factors for these delayedshot migrations over common-shot migration and we discuss some sampling theory issues associated with the formation of delayed-shot records. On both synthetic and real data examples delayed-shot migration has produced images comparable to those
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VSP Salt Flank Imaging through Wavefield Continuation
Authors S. Brandsberg-Dahl, J.P. Van Gestel, J.T. Etgen and B. HornbyB-14 VSP SALT FLANK IMAGING THROUGH WAVEFIELD CONTINUATION Summary We present a method for imaging steeply dipping features such as salt flank by wavefield migration with horizontal propagation. By literally turning a standard shot record migration scheme on its side we ensure that the horizontally propagating waves are properly treated enabling us to image steeply dipping salt flanks. Introduction 1 Sedimentary layers terminating against salt are a common reservoir structure in many hydrocarbon regions around the world. When mapping the closure of such reservoirs both in the prospect evaluation phase and during development and production knowing the location of the
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Limited Frequency Migration with Interpolation
By J.B. BednarB-15 LIMITED FREQUENCY MIGRATION WITH INTERPOLATION 1 Abstract EAGE 65th Conference & Exhibition — Stavanger Norway 2 - 5 June 2003 J. BEE BEDNAR Core Laboratories 2316 Windfern Houston TX 77040 USA Zero-offset migration/inversion of single-frequency data produces asubsurface image with spatialwavenumbersconfinedtoanEwaldspheredefinedbythedouble-square-rootdispersion relation. Fornon-zero-offsetdata theEwaldspherebecomesanEwalddoughnut. Asaresult a single frequency images avolume of wave-numbers. This fact can be exploited to substantially reduce the number of frequencies needed to accurately map subsurface reflectors. This paper investigates a simple recipe for calculating a sparse set of frequencies for use in frequency-slice migration algorithms. While the migration process is unaltered the smaller set of
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A Roadmap for the Maze of 3-D Depth Imaging Choices
More LessB-16 A ROADMAP FOR THE MAZE OF 3-D DEPTH IMAGING CHOICES 1 Summary Today’s explorationist is confronted with a large array of three dimensional depth imaging options ranging from a variety of Kirchhoff implementations to a variety of wave-equation implementations. Historically the choice of a depth migration algorithm was simple: Kirchhoff was the only practical choice. This is no longer the case. Advances in computing and clever algorithms have made waveequation migration an economically feasible alternative. With so many choices making the right choice of imaging method for a given objective can be a daunting task. We briefly examine the
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The International Year of Geosciences, 2004-2007
By H. SchalkeB-17 THE INTERNATIONAL YEAR OF PLANET EARTH GEOSCIENCES FOR SOCIETY 2004-2007 The International Union of Geological Sciences (IUGS) is the international organisation which is representing on behalf of more than 100 national committees the earth scientific community in the International Council for Science (ICSU) where all disciplines meet. The Executive Committee of IUGS has taken the initiative to proclaim an International Year by the UN System and IUGS jointly. The very successful International Geophysical Year in 1957 served as a stimulus and a model. The foremost objective for this initiative is “to demonstrate the substantial and wide-ranging contribution the Earth
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Geoscience and Sustainable Resources in a Global Framework
By A. BjørlykkeB-19 GEOSCIENCE AND SUSTAINABLE RESOURCES IN A GLOBAL FRAMEWORK 1 ARNE BJØRLYKKE Geological Survey of Norway Today the term 'sustainable resource' is propagated widely by scientists the media and international organisations. From a global perspective certain categories of 'sustainable resource' include natural resources—whether solid liquid or gas—which when extracted can be used in the support of human societies. The term 'sustainable' implies thorough knowledge of the nature and extent of the resource as well as an implemented strategy for ensuring its environmentally sound extraction over long time periods and possibly also for securing its renewal. A sustainable use of resources
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Understanding Geohazards
By S. LacasseB-20 UNDERSTANDING GEOHAZARDS Geohazards are events due to geological features and processes that present severe threats to humans property and the natural as well as the built environment. Landslides caused by heavy rainfall floods erosion and human activities are the most common geohazards on land. Near shore and offshore various geological processes earthquakes and human activities for example in connection with petroleum exploration and production can trigger slides. 1 SUZANNE LACASSE ANDERS SOLHEIM and FARROKH NADIM Norwegian Geotechnical Institute P.O. Box 3930 Ullevål Stadion N-0806 Oslo Norway The need to improve the understanding of geohazards is easily exemplified: • In
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Geoscience and Nuclear Waste Disposal – Examples from the Baltic Region
By A.G. MilnesB-21 GEOSCIENCE AND NUCLEAR WASTE DISPOSAL WITH EXAMPLES FROM THE BALTIC REGION 1 Abstract Up to the late 1960s the importance of geoscience for society was seen almost exclusively in terms of the discovery and exploitation of natural resources. The "Limits to Growth" controversy and the growing public perception of environmental degradation started to change and complicate this simple image. In particular in the 1970s the problem of nuclear waste disposal came to dominate the political scene and in many countries thrust geoscience and geoscientists into public view. Since those turbulent years the disposal of nuclear waste in deep underground
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Seismic Arrays – and Their Role in Society
By A. DahleB-22 SEISMIC ARRAYS AND THEIR ROLE IN THE SOCIETY Abstract 1 Prime Minister Nehru of India voiced the heightened international concern over the frequent testing of nuclear arms in 1954 when he proposed the elimination of all nuclear test explosions worldwide. Already during negotiations in Geneva in 1958 it was recognized that seismic arrays could play a vital role in monitoring compliance with nuclear testing treaties. Following a stepwise approach during the next 40 years where international agreements on limited nuclear testing as well as non-proliferation of nuclear arms were achieved the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was finally opened for
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Oceans Apart? Geologists, the Oil Industry and Coping with Climate Change
By H. WilsonB-23 OCEANS APART? GEOLOGISTS THE OIL INDUSTRY AND COPING WITH CLIMATE CHANGE 1 BRYAN LOVELL and HAMISH WILSON In 1997 the year of the Kyoto Climate Summit an Atlantic Divide in the oil industry became apparent. It symbolised the distance between those who think that climate change may not be much influenced by mankind and those who believe that it is. Behind this division lies a serious scientific argument concerning the messages to be read from the story of climate change recorded in rocks and ice. On the one hand are those who suggest that contemporary changes in climate simply
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Paradigm Shift in Fault Interpretation
Authors S.I. Pedersen, A. Hetlelid, P. Fayemendy, T. Skov, T. Randen, T. Iversen and L. SonnelandB-25 PARADIGM SHIFT IN FAULT INTERPRETATION Abstract 1 A high-level fault interpretation workflow using automatically extracted surfaces is presented with special attention on the human interaction part. The first step of the workflow is to generate a fault attribute that enhances the discontinuities in the seismic data. Fault-like surfaces are then extracted using an algorithm called “Ant Tracking”. The surfaces are then loaded into a 3D analysis tool where the interpreter by interactively verifying combining and deleting surfaces decides what is to be the final interpretation. The interpreter works on two levels in the analysis tool; on the fault system
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Improved Imaging in PP and PS, 4C Reservoir Characterization at the Grane Field
Authors J.P. Fjellanger, A.-L. Skjerdingstad, P. Riste, M. Nickel and A. CarrillatB-26 IMPROVED IMAGING IN PP AND PS 4C RESERVOIR CHARACTERIZATION AT THE GRANE FIELD Summary The 3D 4C acquisition at the Grane field was completed in May 2001. Both PP and PS have good quality and high utility value separately. In addition the PP and the PS data are complementary. The data set has high a potential for combined interpretation and analysis. In the following PP is synonymous with PZ the combined hydrophone and vertical geophone data while PS is the converted wave data. Introduction 1 J.P. FJELLANGER 1 A.-L. SKJERDINGSTAD 2 P. RISTE 1 M. NICKEL 3 and A.
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Reservoir Characterization of the Grane Field with Multi-Component Seismic Data
Authors A. Carrillat, M. Nickel, T. Randen, L. Sonneland, T.S. Valen, J.P. Fjellanger and A.-L. SkjerdingstadB-27 RESERVOIR CHARACTERIZATION OF THE GRANE FIELD WITH MULTI-COMPONENT SEISMIC DATA Introduction 1 The Grane Field is located at the eastern margin of the Viking Graben on the western flank of the Utsira high. The Grane Field consists of Palaeocene turbidite sandstones (Heimdal Formation) which originate from the East Shetland Platform to the West of the field. The deposition and geometry of the turbidite sand lobes were mostly controlled by the original basin morphology which forced the sand to deposit along a main N-S axis parallel to the Utsira High. The Heimdal Fm consists of high-density turbidite sandstones that were
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