Download or read book The Effects of Anisotropy on Regional Wave Propagation written by and published by . This book was released on 1997 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crustal rocks can be highly anisotropic, due to (1) oriented minerals (2) oriented cracks, and/or (3) thin layers of material with different elastic stiffnesses. Crustal Love and Rayleigh surface waves couple strongly for anisotropic structures that do not possess a vertical axis of symmetry, and cause explosion to generate significant shear motion on the transverse component 0 seismograms. We developed theory and 1-D layered-media synthetic seismogram codes for anisotropy with an arbitrary axis of symmetry. One code version can synthesize surface waves with periods 100 > T > 0.4 sec. Another code version can synthesize teleseismic body wave reverberations up to 5 Hz. We determined that a tilted axis of symmetry enhances Love-Rayleigh coupling and the scattering of P-waves (compressional) to S-waves (shear). Using P-S scattering, we found evidence for strong (> 10%) anisotropy in the deepest and shallowest crustal layers beneath seismic station ARU (Arti, Russia), an 'open' seismic observatory proximal to the Novaya Zemiya nuclear test site. We also developed a wavelet-base signal processing algorithm that picks out correlated 'signals' from uncorrelated 'noise' in an optimally bandpassed manner Using the Terrascope regional array in California, we applied this algorithm to reconstruct, for a single correlated signal, anomalous amplitudes and polarizations at individual stations, allowing more 'signal' to be recovered than via standard 'stacking'

Download or read book The Effects of Anisotropy on Regional Seismic Wave Propagation written by Jeffrey Park and published by . This book was released on 1995 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have examined the effect of seismic anisotropy on the scattering of surface waves in actively-deforming continental regions, many of which occur in areas of nonproliferation concern. We have approached the problem from three angles, (1) we have developed waveform inversion methods for Love-Rayleigh coupling in seismic data from the Tibetan Plateau and Tien Shan region, (2) we have developed a flat-layered surface wave code to study the effect of crust and upper-mantle anisotropy on crustal resonances, and (3) we have advanced wavelet-based signal processing methods to estimate the polarization of coherent seismic energy across a broadband seismic array. In data from the recent portable broadband PASSCAL deployment in Tibet, we found clear evidence of long-period Love-to-Rayleigh scattering that is best explained by lateral gradients of anisotropy in the upper mantle, developed in the course of the compression and uplift of the plateau. We developed a modal summation technique for waveform perturbations that allowed us to infer that both S and P wave anisotropy, with a ratio consistent with the mineral alignment of sheared peridotite, in the depth range 100-300 km are necessary to fit the observed data. Using a plane-layered geometry, we are investigating the effect of crust and upper mantle anisotropy on Love-Rayleigh coupling in the 5-30 second period range. Most previous studies have posited a horizontal or vertical axis of symmetry for seismic anisotropy, but our code can incorporate a tilted axis of symmetry, which enhances coupling and scattering effects. Such dipping geometries could develop in the crust as a result of thrust ramps in compressive tectonic regimes, either in the form of oriented crystals in shear zones or fine-layering of isotropic material.

Download or read book The Effects of Seismic Anisotropy on Regional Seismic Wave Propagation written by and published by . This book was released on 1997 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crustal rocks can be highly anisotropic, due to (1) oriented minerals, (2) oriented cracks, and/or (3) thin layers of material with different elastic stiffnesses. Crustal Love and Rayleigh surface waves couple strongly for anisotropic structures that do not possess a vertical axis of symmetry, and cause explosions to generate significant shear motion on the transverse component of seismograms. We developed theory and 1-D layered-media synthetic seismogram codes for anisotropy with an arbitrary axis of symmetry. One code version can synthesize surface waves with periods 100 > T > 0.4 sec. Another code version can synthesize teleseismic body wave reverberations up to 5 Hz. We determined that a tilted axis of symmetry enhances Love-Rayleigh coupling and the scattering of P-waves (compressional) to S-waves (shear). Using P-S scattering, we found evidence for strong (> 10%) anisotropy in the deepest and shallowest crustal layers beneath seismic station ARU (Arti, Russia), an 'open' seismic observatory proximal to the Novaya Zemlya nuclear test site. We also developed a wavelet-based signal processing algorithm that picks out correlated 'signals' from uncorrelated 'noise' in an optimally bandpassed manner. Using the Terrascope regional array in California we applied this algorithm to reconstruct, for a single correlated signal anomalous amplitudes and polarizations at individual stations, allowing more 'signal' to be recovered than via standard 'stacking.'

Download or read book Seismic Anisotropy in the Earth written by V. Babuska and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress Induced Anisotropy written by Troy A. Thompson and published by . This book was released on 1998 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Estampes Tableaux Miniatures etc written by and published by . This book was released on 1822 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Core Mantle Boundary Region written by Michael Gurnis and published by American Geophysical Union. This book was released on 1998-02-04 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: The two giant heat engines responsible for plate tectonics and the geodynamo dynamically interact at the core-mantle boundary of the Earth's interior. A multidisciplinary approach is required to determine the composition, structure, and dynamics of the interface. This volume describes original and fundamental research in seismology, geodynamics, mineral physics, and geomagnetism.

Download or read book Research in Regional Seismology written by Batakrishna Mandal and published by . This book was released on 1993 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rock Quality Seismic Velocity Attenuation and Anisotropy written by Nick Barton and published by CRC Press. This book was released on 2006-11-03 with total page 729 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic measurements take many forms, and appear to have a universal role in the Earth Sciences. They are the means for most easily and economically interpreting what lies beneath the visible surface. There are huge economic rewards and losses to be made when interpreting the shallow crust or subsurface more, or less accurately, as the case may be.

Download or read book Seismic Wave Propagation in Stratified Media written by Brian Kennett and published by ANU E Press. This book was released on 2009-05-01 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic Wave Propagation in Stratified Media presents a systematic treatment of the interaction of seismic waves with Earth structure. The theoretical development is physically based and is closely tied to the nature of the seismograms observed across a wide range of distance scales - from a few kilometres as in shallow reflection work for geophysical prospecting, to many thousands of kilometres for major earthquakes. A unified framework is presented for all classes of seismic phenomena, for both body waves and surface waves. Since its first publication in 1983 this book has been an important resource for understanding the way in which seismic waves can be understood in terms of reflection and transmission properties of Earth models, and how complete theoretical seismograms can be calculated. The methods allow the development of specific approximations that allow concentration on different seismic arrivals and hence provide a direct tie to seismic observations.

Download or read book Foundations of Anisotropy for Exploration Seismics written by Klaus Helbig and published by . This book was released on 1994 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applied Seismic Anisotropy written by Colin MacBeth and published by SEG Books. This book was released on 2000 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Subsidence Analysis and Visualization written by Eun Young Lee and published by Springer. This book was released on 2018-06-15 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive introduction to techniques for quantitative subsidence analysis and visualization with example applications. Subsidence analysis is an essential step to understand basin evolution through geologic time and space in the study of sediments and sedimentary basins. Quantifying techniques have been developed and applied in many basin research projects to evaluate total, tectonic and thermal subsidence. They are also a pre-requisite for basin evolution modelling. Recent studies have applied visualization techniques to understand regional subsidence contexts and trends, which confirmed that three-dimensional visualization of the basin subsidence is highly helpful to gain insight into basin evolution. In this book, we show how geoscience and computer science can be effectively combined in advanced basin analysis, especially in terms of basin subsidence. Each type of subsidence analysis is introduced with example applications. In particular we present a study of the Vienna basin using BasinVis, a MATLAB-based program for analyzing and visualizing basin subsidence. Given its breadth of coverage, this book will benefit students in undergraduate and postgraduate courses and provide helpful information for research projects and industry applications.

Download or read book Wave Propagation in Layered Anisotropic Media written by A.H. Nayfeh and published by Elsevier. This book was released on 1995-09-27 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in the study of the dynamic behavior of layered materials in general, and laminated fibrous composites in particular, are presented in this book. The need to understand the microstructural behavior of such classes of materials has brought a new challenge to existing analytical tools. This book explores the fundamental question of how mechanical waves propagate and interact with layered anisotropic media. The chapters are organized in a logical sequence depending upon the complexity of the physical model and its mathematical treatment.

Download or read book Wave Fields in Real Media written by José M. Carcione and published by Elsevier. This book was released on 2014-12-08 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt: Authored by the internationally renowned José M. Carcione, Wave Fields in Real Media: Wave Propagation in Anisotropic, Anelastic, Porous and Electromagnetic Media examines the differences between an ideal and a real description of wave propagation, starting with the introduction of relevant stress-strain relations. The combination of this relation and the equations of momentum conservation lead to the equation of motion. The differential formulation is written in terms of memory variables, and Biot's theory is used to describe wave propagation in porous media. For each rheology, a plane-wave analysis is performed in order to understand the physics of wave propagation. This book contains a review of the main direct numerical methods for solving the equation of motion in the time and space domains. The emphasis is on geophysical applications for seismic exploration, but researchers in the fields of earthquake seismology, rock acoustics, and material science - including many branches of acoustics of fluids and solids - may also find this text useful. New to this edition: This new edition presents the fundamentals of wave propagation in Anisotropic, Anelastic, Porous Media while also incorporating the latest research from the past 7 years, including that of the author. The author presents all the equations and concepts necessary to understand the physics of wave propagation. These equations form the basis for modeling and inversion of seismic and electromagnetic data. Additionally, demonstrations are given, so the book can be used to teach post-graduate courses. Addition of new and revised content is approximately 30%. Examines the fundamentals of wave propagation in anisotropic, anelastic and porous media Presents all equations and concepts necessary to understand the physics of wave propagation, with examples Emphasizes geophysics, particularly, seismic exploration for hydrocarbon reservoirs, which is essential for exploration and production of oil

Download or read book Wave Fields in Real Media written by José M. Carcione and published by Elsevier. This book was released on 2001-10-15 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines the differences between an ideal and a real description of wave propagation, where ideal means an elastic (lossless), isotropic and single-phase medium, and real means an anelastic, anisotropic and multi-phase medium. The analysis starts by introducing the relevant stress-strain relation. This relation and the equations of momentum conservation are combined to give the equation of motion. The differential formulation is written in terms of memory variables, and Biot's theory is used to describe wave propagation in porous media. For each rheology, a plane-wave analysis is performed in order to understand the physics of wave propagation. The book contains a review of the main direct numerical methods for solving the equation of motion in the time and space domains. The emphasis is on geophysical applications for seismic exploration, but researchers in the fields of earthquake seismology, rock acoustics, and material science - including many branches of acoustics of fluids and solids - may also find this text useful.

Download or read book Wave Propagation and Radiation in Gyrotropic and Anisotropic Media written by Abdullah Eroglu and published by Springer Science & Business Media. This book was released on 2010-09-02 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: As technology matures, communication system operation regions shift from mic- wave and millimeter ranges to sub-millimeter ranges. However, device perf- mance at very high frequencies suffers drastically from the material de?ciencies. As a result, engineers and scientists are relentlessly in search for the new types of materials, and composites which will meet the device performance requirements and not present any de?ciencies due to material electrical and magnetic properties. Anisotropic and gyrotropic materials are the class of the materials which are very important in the development high performance microwave devices and new types composite layered structures. As a result, it is a need to understand the wave propagation and radiation characteristics of these materials to be able to realize them in practice. This book is intended to provide engineers and scientists the required skill set to design high frequency devices using anisotropic, and gyrotropic materials by providing them the theoretical background which is blended with the real world engineering application examples. It is the author’s hope that this book will help to ?ll the gap in the area of applied electromagnetics for the design of microwave and millimeter wave devices using new types of materials. Each chapter in the book is designed to give the theory ?rst on the subject and solidify it with application examples given in the last chapter. The application examples for the radiation problems are given at the end of Chap. 5 and Chap. 6 for anisotropic and gyrotropic materials, respectively, after the theory section.