Seismic Diffraction – Modeling, Imaging and Applications
|Prof. Evgeny Landa (Tel Aviv University, Israel)
Dr Tijmen Jan Moser (Moser Geophysical Services, Netherlands)
|Geophysics – Surface Imaging|
|10 CPD points|
CARBONATES DIFFRACTION IMAGING INTERPRETATION FOCUSING DISCONTINUITIES UNCONVENTIONAL TIME-LAPSE INJECTITES FLUID-ESCAPE FEATURES FRACTURES
Diffraction phenomena have been identified as the key seismic manifestation of fractures and other small-scale reservoir heterogeneities. This two-day course will present the current state-of-the-art of diffraction technology and put this in context by a review of its past developments. The course will cover both forward diffraction modeling and diffraction imaging. Case studies of diffraction imaging will be presented covering applications in seismic exploration and other areas of geoscientific interest.
The course will be clearly structured in topics and subtopics. At the end of each topic, a number of bullet points will summarize the items meant to be memorized and taken home by the learner. Interaction between the teacher and learner will be encouraged. The course material will be enlightened by out-of-the box examples demonstrating diffraction phenomena that support the techniques.
By the end of this course, the learner will:
- Have a detailed and up-to-date understanding of the physics of diffraction, diffraction modeling and imaging;
- Be able to effectively communicate the key aspects of diffraction technology with other professionals;
- Have a good understanding of the added value that seismic diffraction brings to current exploration and production projects.
- Motivation, basic ideas and concepts
- Reflection versus diffraction
- Applications of diffraction analysis and imaging
- Interpretation value
- Discovery and founding years (1650-1820): Grimaldi, Huygens, Newton, Young, Fresnel, Poisson, Arago
- Scalar diffraction: mathematical foundation — 19th century: Green, Helmholtz, Kirchhoff, Sommerfeld
- Towards Geometrical Theory of Diffraction — early 20th century: Maggi, Rubinowicz, Keller
- Towards Modern Theory: Trorey, Klem-Musatov
- Diffraction Modeling
- Motivation, definitions, objectives
- Physical modeling
- Numerical modeling: integral methods, boundary layer methods, surface and caustic diffraction, finite differences, time-lapse, scattering methods
- Case study: Diffraction analysis on Ground Penetrating Radar Data
- Case study: Diffraction Response of Salt Diapirs
- Diffraction Imaging in the Time Domain
- Motivation, definitions, objectives
- Anatomy of diffraction
- Diffraction and standard processing
- Detection of diffracted waves
- Separation of diffracted waves
- Inversion of diffracted waves
- Common Reflection Surface/Multifocusing
- Focusing and velocity estimation
- Fracture detection
- Diffraction Imaging in the Depth Domain
- Velocity model considerations
- Illumination: edge and tip diffraction imaging
- Depth imaging: general principles
- Resolution and super-resolution
- Image processing and diffraction imaging
- Diffraction imaging by specularity suppression
- Applications: sandstone reservoirs, time-lapse, stratigraphic terminations against salt, Carbonate reservoirs, shale resource plays, unconventional reservoirs
- Case studies
The target audience of the course consists in geoscientists from industry and academia with a basic knowledge of seismic processing and an interest in innovative interpretation technologies.
Prerequisites are a basic knowledge of seismic processing and imaging and a very elementary mathematical background.
About the instructors
Evgeny Landa obtained his MSc degree in geophysics at Novosibirsk University (1972) and PhD degree in geophysics at Tel Aviv University (1986). He started his carrier in the former Soviet Union, Novosibirsk as a researcher, and senior geophysicist at the Siberian Geophysical Expedition. After immigrating to Israel, he worked at the Geophysical Institute of Israel as a researcher, Head of the R&D group and Head of the Seismic Department (1981—2002), and Director of OPERA (Applied Geophysical Research Group) in Pau (France) (2002-2014) where he was involved in different aspects of seismic data processing, velocity model building and time and depth imaging. His work on velocity model building by coherency inversion has had a strong impact on today’s seismic depth imaging workflows and forms an important part of the GeoDepth (Paradigm) software package. Recently, his research interest involves using non-reflecting energy for increasing seismic resolution and imaging without precise velocity information. He has published more than 60 papers in international journals and his book ‘Beyond Conventional Seismic Imaging’. He is a member of EAGE and SEG, from which he received the Awards of Best Paper (SEG, Honorary Mentioned, 2005) and the EAGE Eotvos Award (2007 and 2009).
Tijmen Jan Moser has a PhD from Utrecht University and has worked as a geophysical consultant for a number of companies and institutes (Amoco, Institut Français du Pétrole, Karlsruhe University, Bergen University, Statoil/Hydro, Geophysical Institute of Israel, Fugro-Jason, Horizon Energy Partners). For the last few years he has been working independently with associations with ZTerra, SGS-Horizon and others. He is based in The Hague, The Netherlands. His main interests include seismic imaging, asymptotic methods, seismic reservoir characterization, diffraction and geothermal exploration. He has authored many influential papers on ray theory and ray methods, Born inversion and modeling, macro-model independent imaging, and diffraction imaging, several of which have received Best Paper awards (SEG, 2005 Honorary mention, EAGE 2007 and 2009, Eotvos Award). He is Editor-in-Chief of Geophysical Prospecting and is serving on SEG's Publication Committee and EAGE's Oil Gas & Geoscience Division Committee. He is a member of SEG and MAA and honorary member of EAGE.
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