Download or read book Imaging and Velocity Analysis by Target oriented Wavefield Inversion written by Yaxun Tang and published by Stanford University. This book was released on 2011 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis develops a novel target-oriented inversion framework that uses wavefields as carriers of information to image both low-wavenumber component (a.k.a. background velocity) and high-wavenumber component (a.k.a. reflectivity) of the earth model in complex geological settings, such as subsalt regions. I address the problem of reflectivity imaging with target-oriented wavefield least-squares migration, and the problem of velocity estimation with target-oriented wavefield tomography. Reflectivity images of the subsurface are commonly produced by prestack depth migration. When the overburden is complex and the reflectors are unevenly or insufficiently illuminated, the migration operator alone is inadequate to provide an optimal image. I tackle the problem of distorted illumination in reflectivity imaging by wavefield least-squares migration. I formulate least-squares migration in the image domain and solve it in a target-oriented fashion. In the image-domain formulation, explicit computation of the Hessian operator (the resolution function that measures the illumination deficiency of the imaging system) is the most important and challenging step. I develop a novel method based on phase encoding to efficiently and accurately compute the target-oriented Hessian operator. The Hessian operator is then used to recover the reflectivity by iterative inverse filtering. I regularize the inversion with dip constraints, which naturally incorporate interpreted geological information into the inversion. Accurate imaging of the reflectivity also requires an accurate background velocity model. High-quality velocity model-building in complex geology requires wavefield-based velocity analysis to properly model band-limited wave phenomena. However, the high cost and lack of flexibility of target-oriented model-building prevent this method from being widely used in practice. I overcome the cost and flexibility issues of wavefield-based migration velocity analysis by developing target-oriented wavefield tomography. Target-oriented wavefield tomography is achieved by synthesizing a new data set specifically for velocity analysis. The new data set is generated based on an initial unfocused target image and by a novel application of generalized Born wavefield modeling, which correctly preserves velocity kinematics by modeling both zero and non-zero subsurface-offset-domain images. The new data set can be synthesized for a chosen target region with velocity inaccuracies. The reduced data size and computation domain, therefore, greatly improve the efficiency and flexibility of wavefield tomography, allowing fast and interpretation-driven interactive wavefield-based velocity analysis, where different geological scenarios or hypotheses can be tested in quasi-real time. The proposed target-oriented inversion framework successfully estimates subsalt velocities and recovers subsalt reflectivities from distorted illumination from 2-D synthetic and 3-D field data.
Download or read book Wavefield Inversion written by Armand Wirgin and published by Springer Science & Business Media. This book was released on 2000-04-19 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an up-to-date presentation of a broad range of contemporary problems in inverse scattering involving acoustic, elastic and electromagnetic waves. Descriptions will be given of traditional (but still in use and subject to on-going improvements) and more recent methods for identifying either: a) the homogenized material parameters of (spatially) unbounded or bounded heterogeneous media, or b) the detailed composition (spatial distribution of the material parameters) of unbounded or bounded heterogeneous media, or c) the location, shape, orientation and material characteristics of an object embedded in a wellcharacterized homogeneous, homogenized or heterogeneous unbounded or bounded medium, by inversion of reflected, transmitted or scattered spatiotemporal recorded waveforms resulting from the propagation of probe radiation within the medium.
Download or read book Migration Velocity Analysis using Image Space Generalized Wavefields written by and published by Stanford University. This book was released on with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Full Seismic Waveform Modelling and Inversion written by Andreas Fichtner and published by Springer Science & Business Media. This book was released on 2010-11-16 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent progress in numerical methods and computer science allows us today to simulate the propagation of seismic waves through realistically heterogeneous Earth models with unprecedented accuracy. Full waveform tomography is a tomographic technique that takes advantage of numerical solutions of the elastic wave equation. The accuracy of the numerical solutions and the exploitation of complete waveform information result in tomographic images that are both more realistic and better resolved. This book develops and describes state of the art methodologies covering all aspects of full waveform tomography including methods for the numerical solution of the elastic wave equation, the adjoint method, the design of objective functionals and optimisation schemes. It provides a variety of case studies on all scales from local to global based on a large number of examples involving real data. It is a comprehensive reference on full waveform tomography for advanced students, researchers and professionals.
Download or read book Seismic Imaging and Inversion Volume 1 written by Robert H. Stolt and published by Cambridge University Press. This book was released on 2012-02-09 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extracting information from seismic data requires knowledge of seismic wave propagation and reflection. The commonly used method involves solving linearly for a reflectivity at every point within the Earth, but this book follows an alternative approach which invokes inverse scattering theory. By developing the theory of seismic imaging from basic principles, the authors relate the different models of seismic propagation, reflection and imaging - thus providing links to reflectivity-based imaging on the one hand and to nonlinear seismic inversion on the other. The comprehensive and physically complete linear imaging foundation developed presents new results at the leading edge of seismic processing for target location and identification. This book serves as a fundamental guide to seismic imaging principles and algorithms and their foundation in inverse scattering theory, and is a valuable resource for working geoscientists, scientific programmers and theoretical physicists.
Download or read book Seismic Inversion written by Gerard T. Schuster and published by SEG Books. This book was released on 2017-07-01 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the theory and practice of inverting seismic data for the subsurface rock properties of the earth. The primary application is for inverting reflection and/or transmission data from engineering or exploration surveys, but the methods described also can be used for earthquake studies. Seismic Inversion will be of benefit to scientists and advanced students in engineering, earth sciences, and physics. It is desirable that the reader has some familiarity with certain aspects of numerical computation, such as finite-difference solutions to partial differential equations, numerical linear algebra, and the basic physics of wave propagation. For those not familiar with the terminology and methods of seismic exploration, a brief introduction is provided. To truly understand the nuances of seismic inversion, we have to actively practice what we preach (or teach). Therefore, computational labs are provided for most of the chapters, and some field data labs are given as well.
Download or read book Seismic Diffraction written by Tijmen Jan Moser and published by SEG Books. This book was released on 2016-06-30 with total page 823 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of diffraction imaging to complement the seismic reflection method is rapidly gaining momentum in the oil and gas industry. As the industry moves toward exploiting smaller and more complex conventional reservoirs and extensive new unconventional resource plays, the application of the seismic diffraction method to image sub-wavelength features such as small-scale faults, fractures and stratigraphic pinchouts is expected to increase dramatically over the next few years. “Seismic Diffraction” covers seismic diffraction theory, modeling, observation, and imaging. Papers and discussion include an overview of seismic diffractions, including classic papers which introduced the potential of diffraction phenomena in seismic processing; papers on the forward modeling of seismic diffractions, with an emphasis on the theoretical principles; papers which describe techniques for diffraction mathematical modeling as well as laboratory experiments for the physical modeling of diffractions; key papers dealing with the observation of seismic diffractions, in near-surface-, reservoir-, as well as crustal studies; and key papers on diffraction imaging.
Download or read book Petroleum Abstracts written by and published by . This book was released on 1997 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coalbed Methane in China written by Yan Song and published by Springer Nature. This book was released on 2021-02-09 with total page 463 pages. Available in PDF, EPUB and Kindle. Book excerpt: The coalbed methane (CBM) reserve in China ranks third in the world with a total resource of 36.8×1012 m3. Exploitation of CBM has an important practical significance to ensure the long-term rapid development of China natural gas industry. Therefore, in 2002, the Ministry of Science and Technology of China set up a national 973 program to study CBM system and resolve problems of CBM exploration and exploitation in China. All the main research results and new insights from the program are presented in this book. The book is divided into 11 chapters. The first chapter mainly introduces the present situation of CBM exploration and development in China and abroad. Chapters 2 through 9 illustrate the geological theory and prospect evaluation methods. Then chapters 10 and 11 discuss CBM recovery mechanisms and technology. The book systematically describes the origin, storage, accumulation and emission of CBM in China, and also proposes new methods and technologies on resource evaluation, prospect prediction, seismic interpretation and enhanced recovery. The book will appeal to geologists, lecturers and students who are involved in the CBM industry and connected with coal and conventional hydrocarbon resources research.
Download or read book 3D Seismic Imaging written by Biondo Biondi and published by SEG Books. This book was released on 2006 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accompanying CD-ROM includes PDF slides for teaching the material in the book and the C3-narrow-azimuth classic data set.
Download or read book Geophysics Today written by Sergey Fomel and published by SEG Books. This book was released on 2010 with total page 543 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents a collection of papers which appear in the September-October 2010 Geophysics special section, written by recognised experts in various areas of exploration geophysics, plus an additional group of papers drawn from Geophysics which address areas beyond those invited articles. The result is a snapshot of the state-of-the-art in the field.
Download or read book 3C Seismic and VSP Converted waves and vector wavefield applications written by James Gaiser and published by SEG Books. This book was released on 2016-06-30 with total page 637 pages. Available in PDF, EPUB and Kindle. Book excerpt: 3C seismic applications provide enhanced rock property characterization of the reservoir that can complement P-wave methods. Continued interest in converted P- to S-waves (PS-waves) and vertical seismic profiles (VSPs) has resulted in the steady development of advanced vector wavefield techniques. PS-wave images along with VSP data can be used to help P-wave interpretation of structure in gas obscured zones, of elastic and fluid properties for lithology discrimination from S-wave impedance and density inversion in unconventional reservoirs, and of fracture characterization and stress monitoring from S-wave birefringence (splitting) analysis. The book, which accompanies the 2016 SEG Distinguished Instructor Short Course, presents an overview of 3C seismic theory and practical application: from fundamentals of PS-waves and VSPs, through to acquisition and processing including interpretation techniques. The emphasis is on unique aspects of vector wavefields, anisotropy, and the important relationships that unify S-waves and P-waves. Various applications and case studies demonstrate image benefits from PS-waves, elastic properties and fluid discrimination from joint inversion of amplitude variations with offset/angle (AVO/A), and VSP methods for anisotropic velocity model building and improved reservoir imaging. The book will be of interest to geophysicists, geologists, and engineers, especially those involved with or considering the use of AVO/A inversion, fracture/stress characterization analyses, or interpretation in gas-obscured reservoirs.
Download or read book Seismic Inversion written by Yanghua Wang and published by John Wiley & Sons. This book was released on 2016-09-15 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic inversion aims to reconstruct a quantitative model of the Earth subsurface, by solving an inverse problem based on seismic measurements. There are at least three fundamental issues to be solved simultaneously: non-linearity, non-uniqueness, and instability. This book covers the basic theory and techniques used in seismic inversion, corresponding to these three issues, emphasising the physical interpretation of theoretical concepts and practical solutions. This book is written for master and doctoral students who need to understand the mathematical tools and the engineering aspects of the inverse problem needed to obtain geophysically meaningful solutions. Building on the basic theory of linear inverse problems, the methodologies of seismic inversion are explained in detail, including ray-impedance inversion and waveform tomography etc. The application methodologies are categorised into convolutional and wave-equation based groups. This systematic presentation simplifies the subject and enables an in-depth understanding of seismic inversion. This book also provides a practical guide to reservoir geophysicists who are attempting quantitative reservoir characterisation based on seismic data. Philosophically, the seismic inverse problem allows for a range of possible solutions, but the techniques described herein enable geophysicists to exclude models that cannot satisfy the available data. This book summarises the author’s extensive experience in both industry and academia and includes innovative techniques not previously published.
Download or read book Reverse Time Imaging in Solid Earth and Exploration Geophysics written by Hua-Wei Zhou and published by Frontiers Media SA. This book was released on 2022-06-28 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Seismic Interferometry written by Deyan Draganov and published by SEG Books. This book was released on 2008 with total page 641 pages. Available in PDF, EPUB and Kindle. Book excerpt: Including more than 70 papers, this invaluable source for researchers and students contains an editors' introduction with extensive references and chapters on seismic interferometry without equations, highlights of the history of seismic interferometry from 1968 until 2003, and offers a detailed overview of the rapid developments since 2004.
Download or read book Sequential Seismic Inversion Using Plane wave Synthesis written by Jun Ji and published by . This book was released on 1995 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Seismic Imaging a Practical Approach written by Jean-Luc Mari and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the geophysics of oil exploration and reservoir studies, the surface seismic method is the most commonly used method to obtain a subsurface model in 2 or 3 dimensions. This method plays an increasingly important role in soil investigations for geotechnical, hydrogeological and site characterization studies regarding seismic hazard issues. The goal of this book is to provide a practical guide, using examples from the field, to the application of seismic methods to surface imaging. After reviewing the current state of knowledge in seismic wave propagation, refraction and reflection seismic methods, the book aims to describe how seismic tomography and fullwave form inversion methods can be used to obtain seismic images of the subsurface. Through various synthetic and field examples, the book highlights the benefit of combining different sets of data: refracted waves with reflected waves, and body waves with surface waves. With field data targeting shallow structures, it shows how more accurate geophysical models can be obtained by using the proposed hybrid methods. Finally, it shows how the integration of seismic data (3D survey and VSP), logging data (acoustic logging) and core measurements, combined with a succession of specific and advanced processing techniques, enables the development of a 3D high resolution geological model in depth. In addition to these examples, the authors provide readers with guidelines to carry out these operations, in terms of acquisition, as well as processing and interpretation. In each chapter, the reader will find theoretical concepts, practical rules and, above all, actual application examples. For this reason, the book can be used as a text to accompany course lectures or continuing education seminars. This book aims to promote the exchange of information among geologists, geophysicists, and engineers in geotechnical fields.
