Download or read book Multi component VSP Analysis for Applied Seismic Anisotropy written by Colin MacBeth and published by Elsevier. This book was released on 2002 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: The vertical seismic profile, acquired with an array of 3C receivers and either a single source or several arranged in a multi-component configuration, provides an ideal high fidelity calibration tool for seismic projects involved in the application of seismic anisotropy. This book catalogues the majority of specialized tools necessary to work with P-P, P-S and S-S data from such VSP surveys at the acquisition design, processing and interpretation stages. In particular, it discusses 3C, 4C, 6C and 9C VSP, marine and land surveys with near and multiple offsets (walkways), azimuths (walkarounds) or a combination of both. These are considered for TIH or TIV flavours of seismic anisotropy arising from cracks, fractures, sedimentary layering, and shales. The anisotropic adaptation of familiar seismic methods for velocity analysis and inversion, reflected amplitude interpretation, are given together with more multi-component specific algorithms based upon the principles dictated by the vector convolutional model. Thus, multi-component methods are described that provide tests and compensation for source or receiver vector fidelity, tool rotation correction, layer stripping, near-surface correction, wavefield separation, and the Alford rotation with its variants. The work will be of interest to geophysicists involved in research or the application of seismic anisotropy using multi-component seismic.
Download or read book Analysis of Seismic Anisotropy in 3D Multi component Seismic Data written by Zhongping Qian and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Seismic Anisotropy in 3D Multi component Seismic Data written by Zhongping Qian and published by . This book was released on 2010 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of seismic anisotropy has been recognized by the oil industry since its first observation in hydrocarbon reservoirs in 1986, and the application of seismic anisotropy to solve geophysical problems has been keenly pursued since then. However, a lot of problems remain, which have limited the applications of the technology. Nowadays, more and more 3D multi-component seismic data with wide-azimuth are becoming available. These have provided more opportunities for the study of seismic anisotropy. My thesis has focused on the study of using seismic anisotropy in 3D multi-component seismic data to characterize subsurface fractures, improve converted wave imaging and detect fluid content in fractured reservoirs, all of which are important for fractured reservoir exploration and monitoring. For the use of seismic anisotropy to characterize subsurface fracture systems, equivalent medium theories have established the link between seismic anisotropy and fracture properties. The numerical modelling in the thesis reveals that the amplitudes and interval travel-time of the radial component of PS converted waves can be used to derive fracture properties through elliptical fitting similar to P-waves. However, sufficient offset coverage is required for either the P- or PS-wave to reveal the features of elliptical variation with azimuth. Compared with numerical modelling, seismic physical modelling provides additional insights into the azimuthal variation of P and PS-wave attributes and their links with fracture properties. Analysis of the seismic physical model data in the thesis shows that the ratio of the offset to the depth of a target layer (offset-depth ratio), is a key parameter controlling the choice of suitable attributes and methods for fracture analysis. Data with a small offset-depth ratio from 0.7 to 1.0 may be more suitable for amplitude analysis; whilst the use of travel time or velocity analysis requires a large offset-depth ratio above 1.0, which can help in reducing the effect of the acquisition footprint and structural imprint on the results. Multi-component seismic data is often heavily contaminated with noise, which will limit its application potential in seismic anisotropy analysis. A new method to reduce noise in 3D multi-component seismic data has been developed and has proved to be very helpful in improving data quality. The method can automatically recognize and eliminate strong noise in 3D converted wave seismic data with little interference to useful reflection signals. Component rotation is normally a routine procedure in 3D multi-component seismic analysis. However, this study shows that incorrect rotations may occur for certain acquisition geometry and can lead to errors in shear-wave splitting analysis. A quality control method has been developed to ensure this procedure is correctly carried out. The presence of seismic anisotropy can affect the quality of seismic imaging, but the study has shown that the magnitude of the effects depends on the data type and target depth. The effects of VTI anisotropy (transverse isotropy with a vertical symmetry axis) on P-wave images are much weaker than those on PS-wave images. Anisotropic effects decrease with depth for the P- and PS-waves. The real data example shows that the overall image quality of PS-waves processed by pre-stack time migration has been improved when VTI anisotropy has been taken into account. The improvements are mainly in the upper part of the section. Monitoring fluid distribution is an important task in producing reservoirs. A synthetic study based on a multi-scale rock-physics model shows that it is possible to use seismic anisotropy to derive viscosity information in a HTI medium (transverse isotropy with a horizontal symmetry axis). The numerical modelling demonstrates the effects of fluid viscosity on medium elastic properties and seismic reflectivity, as well as the possibility of using them to discriminate between oil and water saturation. Analysis of real data reveals that it is hard to use the P-wave to discriminate oil-water saturation. However, characteristic shear-wave splitting behaviour due to pore pressure changes demonstrates the potential for discriminating between oil and water saturation in fractured reservoirs.
Download or read book Seismology of Azimuthally Anisotropic Media and Seismic Fracture Characterization written by I. D. T︠S︡vankin and published by SEG Books. This book was released on 2011 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents an analysis of seismic signatures for azimuthally anisotropic media and shows anisotropic inversion/processing methods for wide-azimuth reflection data and VSP surveys. The focus is kinematic parameter-estimation techniques; the prestack amplitudes section includes AVO and attenuation coefficients; field examples are included.
Download or read book Seismic Signatures and Analysis of Reflection Data in Anisotropic Media written by Ilya Tsvankin and published by SEG Books. This book was released on 2012 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides essential background on anisotropic wave propagation, introduces efficient notation for transversely isotropic (TI) and orthorhombic media, and identifies the key anisotropy parameters for imaging and amplitude analysis. Particular attention is given to moveout analysis and P-wave time-domain processing for VTI and TTI.
Download or read book Seismic Signatures and Analysis of Reflection Data in Anisotropic Media written by I. Tsvankin and published by Elsevier. This book was released on 2001-03-02 with total page 455 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following the breakthrough in the last decade in identifying the key parameters for time and depth imaging in anisotropic media and developing practical methodologies for estimating them from seismic data, this title primarily focuses on the far reaching exploration benefits of anisotropic processing.This volume provides the first comprehensive description of reflection seismic signatures and processing methods in anisotropic media. It identifies the key parameters for time and depth imaging in transversely isotropic media and describes practical methodologies for estimating them from seismic data. Also, it contains a thorough discussion of the important issues of uniqueness and stability of seismic velocity analysis in the presence of anisotropy. The book contains a complete description of anisotropic imaging methods, from the theoretical background to algorithms to implementation issues. Numerous applications to synthetic and field data illustrate the improvements achieved by the anisotropic processing and the possibility of using the estimated anisotropic parameters in lithology discrimination.
Download or read book Anisotropy and Microseismics Theory and Practice written by Vladimir Grechka and published by SEG Books. This book was released on 2020-08-01 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: Takes readers on a path of discovery of rarely examined wave phenomena and their possible usage. Chapters begin by formulating a question, followed by explanations of what is exciting about it, where the mystery might lie, and what could be the potential value of answering the question.
Download or read book The Relationship Between Damage and Localization written by Helen Lewis and published by Geological Society of London. This book was released on 2007 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: The many kinds of porous geomaterials (rocks, soils, concrete, etc.) exhibit a range of responses when undergoing inelastic deformation. In doing so they commonly develop well-ordered fabric elements, forming fractures, shear bands and compaction bands, so creating the planar fabrics that are regarded as localization. Because these induced localization fabrics alter the bulk material properties (such as permeability, acoustic characteristics and strength), it is important to understand how and why localization occurs, and how it relates to its setting. The concept of damage (in several uses) describes both the precursor to localization and the context within which it occurs. A key theme is that geomaterials display a strong material evolution during deformation, revealing a close linkage between the damage and localization processes. This volume assembles perspectives from a number of disciplines, including soil mechanics, rock mechanics, structural geology, seismic anisotropy and reservoir engineering. The papers range from theoretical to observational, and include contributions showing how the deformed geomaterial's emergent bulk characteristics, like permeability and seismic anisotropy, can be predicted.
Download or read book Multi component Seismic Modeling and Robust Pre stack Seismic Waveform Inversion for Elastic Anisotropic Media Parameters written by Tao Li and published by . This book was released on 2016 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Consideration of azimuthal anisotropy, at least to an orthorhombic symmetry is important in exploring the naturally fractured and unconventional hydrocarbon reservoirs. Full waveform inversion of multicomponent seismic data can, in principle, provide more robust estimates of subsurface elastic parameters and density than the inversion of single component (P wave) seismic data. In addition, azimuthally dependent anisotropy can only be resolved by carefully studying the multicomponent seismic displacement data acquired and processed along different azimuths. Such an analysis needs an inversion algorithm capable of simultaneously optimizing multiple objectives, one for each data component along each azimuth. In this dissertation, I propose a novel multiobjective methodology using a parallelized version of NSGA II for waveform inversion of multicomponent seismic data along two azimuths. The proposed methodology is also an improvement of the original NSGA II in overall computational efficiency, preservation of population diversity, and rapid sampling of the model space. Next, the proposed methodology is applied on wide azimuth and multicomponent vertical seismic profile (VSP) data to provide reliable estimation of subsurface anisotropy at and near the well location. Prestack waveform inversion was applied to the wide-azimuth multicomponent VSP data acquired at the Wattenberg Field, located in Denver Basin of northeastern Colorado, USA, to characterize the Niobrara formation for azimuthal anisotropy. By comparing the waveform inversion results with an independent study that used a joint slowness-polarization approach to invert the same data, we conclude that the waveform inversion is a reliable tool for inverting the wide-azimuth multicomponent VSP data for anisotropy estimation. Last but not least, an anisotropic elastic three-dimensional scheme for modeling the elastodynamic wavefield is developed in order to go beyond the 1D layering assumption being used in previous studies. The method uses quadratic tetrahedral elements to discretize the model in space, Newmark family of time integration scheme to discretize in time, and a perfectly matched layer as the absorbing boundary condition. Various preconditioned conjugate gradient approaches were tested and implemented in the algorithm to improve the numerical efficiency of the finite element solver and the entire methodology was optimized to run efficiently in a parallel computing architecture. By computing synthetic seismic responses for a homogeneous medium and for a layered anisotropic medium and comparing results with other analytical and numerical solutions, the validity of the methodology was also verified for numerical accuracy.
Download or read book Seismic While Drilling written by F.B Poletto and published by Elsevier. This book was released on 2022-08-13 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic While Drilling: Fundamentals of Drill-Bit Seismic for Exploration, 2nd edition, revised and extended gives a theoretical and practical introduction to seismic while drilling by using drill-bit noise. While drilling seismic methods using surface sources and downhole receivers are also analysed. The goal is to support the exploration geology with geophysical control of drilling, and to build a bridge between geophysicists involved in seismic while drilling, drillers and exploration geologists. This revised and extended edition includes new topics such as novel drilling technology, downhole communication, ground-force drill-bit measurement, SWD seismic interferometry, and fiber optic (DAS). A new section is dedicated to well placement and geosteering. Like the first edition, Seismic While Drilling, 2nd edition also includes examples of SWD analysis and application on real data. - Addresses fundamental knowledge on geophysical principles related to acoustics and seismic waves as well as basic borehole waves and drilling - Includes new technological and methodological developments since the publication of the first edition - Provides new examples for applications in geothermal and analysis of diffractions, offshore marine, and tunnel seismic while drilling (TSWD)
Download or read book Understanding Seismic Anisotropy in Exploration and Exploitation written by Leon Thomsen and published by SEG Books. This book was released on 2002 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: All rock masses are seismically anisotropic, but we generally ignore this in our seismic acquisition, processing, and interpretation. The anisotropy nonetheless does affect our data, in ways that limit the effectiveness with which we can use it, as long as we ignore it. This book, produced for use with the fifth SEG/EAGE Distinguished Instructor Short Course, helps us understand why this inconsistency between reality and practice has been so successful in the past and why it will be less successful in the future as we acquire better seismic data (especially including vector seismic data) and correspondingly higher expectations of it. This book helps us understand how we can modify our practice to more fully realize the potential inherent in our data through algorithms which recognize the fact of seismic anisotropy.
Download or read book Seismic Amplitude written by Rob Simm and published by Cambridge University Press. This book was released on 2014-04-17 with total page 283 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic amplitudes yield key information on lithology and fluid fill, enabling interpretation of reservoir quality and likelihood of hydrocarbon presence. The modern seismic interpreter must be able to deploy a range of sophisticated geophysical techniques, such as seismic inversion, AVO (amplitude variation with offset), and rock physics modelling, as well as integrating information from other geophysical techniques and well data. This accessible, authoritative book provides a complete framework for seismic amplitude interpretation and analysis in a practical manner that allows easy application - independent of any commercial software products. Deriving from the authors' extensive industry expertise and experience of delivering practical courses on the subject, it guides the interpreter through each step, introducing techniques with practical observations and helping to evaluate interpretation confidence. Seismic Amplitude is an invaluable day-to-day tool for graduate students and industry professionals in geology, geophysics, petrophysics, reservoir engineering, and all subsurface disciplines making regular use of seismic data.
Download or read book Seismic Waves and Rays in Elastic Media written by M.A. Slawinski and published by Elsevier. This book was released on 2003-08-04 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book seeks to explore seismic phenomena in elastic media and emphasizes the interdependence of mathematical formulation and physical meaning. The purpose of this title - which is intended for senior undergraduate and graduate students as well as scientists interested in quantitative seismology - is to use aspects of continuum mechanics, wave theory and ray theory to describe phenomena resulting from the propagation of waves.The book is divided into three parts: Elastic continua, Waves and rays, and Variational formulation of rays. In Part I, continuum mechanics are used to describe the material through which seismic waves propagate, and to formulate a system of equations to study the behaviour of such material. In Part II, these equations are used to identify the types of body waves propagating in elastic continua as well as to express their velocities and displacements in terms of the properties of these continua. To solve the equations of motion in anisotropic inhomogeneous continua, the high-frequency approximation is used and establishes the concept of a ray. In Part III, it is shown that in elastic continua a ray is tantamount to a trajectory along which a seismic signal propagates in accordance with the variational principle of stationary travel time.
Download or read book Seismic Amplitude Inversion in Reflection Tomography written by Yanghua Wang and published by Elsevier. This book was released on 2003-02-25 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first book of its kind on seismic amplitude inversion in the context of reflection tomography. The aim of the monograph is to advocate the use of ray-amplitude data, separately or jointly with traveltime data, in reflection seismic tomography.The emphasis of seismic exploration is on imaging techniques, so that seismic section can be interpreted directly as a geological section. In contrast it is perhaps ironic that, in decades of industrial seismology, one major aspect of waveform data that potentially is easier to measure and analyse has generally been ignored. That is, the information content of seismic amplitudes. Perhaps the potential complexity has deterred most researchers from a more thorough investigation of the practical use of seismic amplitude data. The author of this volume presents an authoritative and detailed study of amplitude data, as used in conjunction with traveltime data, to provide better constraints on the variation of seismic wave speed in the subsurface.One of the fundamental problems in conventional reflection seismic tomography using only traveltime data is the possible ambiguity between the velocity variation and the reflector depth. The inclusion of amplitude data in the inversion may help to resolve this problem because the amplitudes and traveltimes are sensitive to different features of the subsurface model, and thereby provide more accurate information about the subsurface structure and the velocity distribution. An essential goal of this monograph is to make the amplitude inversion method work with real reflection seismic data.
Download or read book Quantitative Borehole Acoustic Methods written by X.M. Tang and published by Elsevier. This book was released on 2004-01-27 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic logging is a multidisciplinary technology involving basic theory, instrumentation, and data processing/interpretation methodologies. The advancement of the technology now allows for a broad range of measurements to obtain formation properties such as elastic wave velocity and attenuation, formation permeability, and seismic anisotropy that are important for petroleum reservoir exploration. With these advances, it is easier to detect and characterize formation fractures, estimate formation stress field, and locate/estimate petroleum reserves. The technology has evolved from the monopole acoustic logging into the multipole, including dipole, cross-dipole, and even quadrupole, acoustic logging measurements. The measurement process has developed from the conventional wireline logging into the logging-while-drilling stage. For such a fast developing technology with applications that are interesting to readers of different backgrounds, it is necessary to have systematic documentation of the discipline, including the theory, methods, and applications, as well as the technology's past, present, and near future development trends. Quantitative Borehole Acoustic Methods provides such documentation, with emphasis on the development over the past decade. Although considerable effort has been made to provide a thorough basis for the theory and methodology development, emphasis is placed on the applications of the developed methods. The applications are illustrated with field data examples. Many of the acoustic waveform analysis/processing methods described in the book are now widely used in the well logging industry.
Download or read book Waves And Rays In Elastic Continua written by Michael A Slawinski and published by World Scientific Publishing Company. This book was released on 2010-09-09 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present book — which is the second, and significantly extended, edition of the textbook originally published by Elsevier Science — emphasizes the interdependence of mathematical formulation and physical meaning in the description of seismic phenomena. Herein, we use aspects of continuum mechanics, wave theory and ray theory to explain phenomena resulting from the propagation of seismic waves.The book is divided into three main sections: Elastic Continua, Waves and Rays and Variational Formulation of Rays. There is also a fourth part, which consists of appendices.In Elastic Continua, we use continuum mechanics to describe the material through which seismic waves propagate, and to formulate a system of equations to study the behaviour of such a material. In Waves and Rays, we use these equations to identify the types of body waves propagating in elastic continua as well as to express their velocities and displacements in terms of the properties of these continua. To solve the equations of motion in anisotropic inhomogeneous continua, we invoke the concept of a ray. In Variational Formulation of Rays, we show that, in elastic continua, a ray is tantamount to a trajectory along which a seismic signal propagates in accordance with the variational principle of stationary traveltime. Consequently, many seismic problems in elastic continua can be conveniently formulated and solved using the calculus of variations. In the Appendices, we describe two mathematical concepts that are used in the book; namely, homogeneity of a function and Legendre's transformation. This section also contains a list of symbols.
Download or read book Nuclear Magnetic Resonance written by K.-J. Dunn and published by Elsevier. This book was released on 2002-01-25 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: The applications of nuclear magnetic resonance (NMR) to petroleum exploration and production have become more and more important in recent years. The development of the NMR logging technology and the NMR applications to core analysis and formation evaluation have been very rapid and extensive.The scope of this book covers a wide range of NMR related petrophysical measurements on cores including brief descriptions of recent applications of Magic Angle Spinning (MAS) NMR and the basics of NMR imaging of cores. In the discussion of NMR logging applications various schemes of using NMR logs to obtain necessary information for formation evaluation are outlined, such as irreducible water saturation determination, hydrocarbon typing, oil viscosity estimation, and permeability prediction. The principles of these applications are discussed using schematic diagrams for illustration.A unique aspect of the book is that it provides a detailed account of the basic principles of spin diffusion and relaxation in porous media. Another important area that is covered is the inversion of NMR data into a distribution of amplitudes associated with relaxation time which provides the basic information needed to interpret the NMR measurements obtained from logging.
