Love and Rayleigh Waves in the Microseismic Noise Field PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Love and Rayleigh Waves in the Microseismic Noise Field PDF full book. Access full book title Love and Rayleigh Waves in the Microseismic Noise Field by Carina C. Juretzek. Download full books in PDF and EPUB format.
Author: Carina C. Juretzek
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Carina C. Juretzek
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Shipra Sethi
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
Book Description
Seismic noise is the continuous oscillation of the Earth recorded at every station in the absence of earthquakes . The interaction of atmosphere, ocean waves and earth creates them. The dominant signal, called secondary microseisms in the frequency band 0.1-0.3 Hz have known to be formed due to the non-linear interaction between two oppositely traveling ocean gravity waves. The resulting pressure fluctuations close to the ocean surface generates a seismic signal which is dominantly Rayleigh waves (R). Many authors reported the observations of Love wave content (L) in the seismic signal. However the L/R amplitude ratio is shown to vary depending on the area investigated. The generation mechanism of Rayleigh waves due to these noise sources interacting with the sea-bottom is well understood and modeled. The explanation why Love waves are generated is unclear because the source in the ocean cannot generate shear motion. We have shown the existence of Rayleigh and Love waves recorded by the Alaska and California network. We then investigate the effect of ocean-continental slope boundary on the seismic noise amplitude of secondary microsiesm and quantify the Rayleigh-to-Love wave conversion. In order to do that, we use the spectral element method to numerically simulate the seismic wave field in 3D media. The primary focus of this study is on investigating several factors that can influence the seismic noise amplitude recorded on the continent in the frequency band 0.1-1 Hz. Those factors are a) the ocean-thickness, b) the source-site effect i.e., source close to the boundary and far from the boundary, c) the sedimentary layer beneath the sea-bottom and d) the effect of ocean-continental slope angle. We observe that Love waves can be generated at the ocean-continental boundary, however the amplitude change is frequency dependent. We observe energy in the transverse direction in a model that cannot generate Love waves as a result of conversion at the ocean-continental slope boundary. The strongest Love wave amplitude is recorded in a model with 6 km deep ocean at resonant frequencies in the ocean when the source is far from the coast. However at other frequencies, shallow oceans and source close to the boundary generates highest Love wave amplitude. In the presence of sediments, the amplification of Love waves is higher at shorter periods for both sources. The reduction in slope angle diminishes the Love wave amplitude. For both source close and far from the boundary, the L/R amplitude ratio vary strongly with frequency and ocean thickness. Among all the factors, highest L/R amplitude ratios are generated due to sediments when the source is close to the boundary.
Author: Nori Nakata
Publisher: Cambridge University Press
ISBN: 1108417086
Category : Nature
Languages : en
Pages : 373
Get Book Here
Book Description
A comprehensive overview of seismic ambient noise, covering observations, physical origins, modelling, processing methods and applications in imaging and monitoring.
Author: Harsh Gupta
Publisher: Springer Science & Business Media
ISBN: 904818701X
Category : Science
Languages : en
Pages : 1579
Get Book Here
Book Description
The past few decades have witnessed the growth of the Earth Sciences in the pursuit of knowledge and understanding of the planet that we live on. This development addresses the challenging endeavor to enrich human lives with the bounties of Nature as well as to preserve the planet for the generations to come. Solid Earth Geophysics aspires to define and quantify the internal structure and processes of the Earth in terms of the principles of physics and forms the intrinsic framework, which other allied disciplines utilize for more specific investigations. The first edition of the Encyclopedia of Solid Earth Geophysics was published in 1989 by Van Nostrand Reinhold publishing company. More than two decades later, this new volume, edited by Prof. Harsh K. Gupta, represents a thoroughly revised and expanded reference work. It brings together more than 200 articles covering established and new concepts of Geophysics across the various sub-disciplines such as Gravity, Geodesy, Geomagnetism, Seismology, Seismics, Deep Earth Processes, Plate Tectonics, Thermal Domains, Computational Methods, etc. in a systematic and consistent format and standard. It is an authoritative and current reference source with extraordinary width of scope. It draws its unique strength from the expert contributions of editors and authors across the globe. It is designed to serve as a valuable and cherished source of information for current and future generations of professionals.
Author: Charles J. Ammon
Publisher: Academic Press
ISBN: 0128165170
Category : Science
Languages : en
Pages : 604
Get Book Here
Book Description
Modern Global Seismology, Second Edition, is a complete, self-contained primer on seismology, featuring extensive coverage of all related aspects—from observational data through prediction—and emphasizing the fundamental theories and physics governing seismic waves, both natural and anthropogenic. Based on thoroughly class-tested material, the text provides a unique perspective on Earth’s large-scale internal structure and dynamic processes, particularly earthquake sources, and the application of theory to the dynamic processes of the earth’s upper layer. This insightful new edition is designed for accessibility and comprehension for graduate students entering the field. Exploration seismologists will also find it an invaluable resource on topics such as elastic-wave propagation, seismic instrumentation, and seismogram analysis. Includes more than 400 illustrations, from both recent and traditional research articles, to help readers visualize mathematical relationships, as well as boxed features to explain advanced topics Offers incisive treatments of seismic waves, waveform evaluation and modeling, and seismotectonics, as well as quantitative treatments of earthquake source mechanics and numerous examples of modern broadband seismic recordings Covers current seismic instruments and networks and demonstrates modern waveform inversion methods Includes extensive, updated references for further reading new to this edition Features reorganized chapters split into two sections, beginning with introductory content such as tectonics and seismogram analysis, and moving on to more advanced topics, including seismic wave excitation and propagation, multivariable and vector calculus, and tensor approaches Completely updated references and figures to bring the text up to date Includes all-new sections on recent advancements and to enhance examples and understanding Split into shorter chapters to allow more flexibility for instructors and easier access for researchers, and includes exercises
Author: Z. S. Andrianova
Publisher: Springer Science & Business Media
ISBN: 1468486047
Category : Science
Languages : en
Pages : 99
Get Book Here
Book Description
Among seismic waves generated by widely dilferent types of sources, the waves that are the most interest ing and of the longest duration are usually surface waves (which are also called normal waves, interference and channel waves, natural vibrations of layers, etc. ). These waves are distinguished by their dispersion and reso nance, and are used in many investigations - in the determination of the structure of the medium (the existence of surface layers and waveguides), in the determination of the coordinates and properties of the source (in par ticular its energy and mechanism), in the identification of subterranean exploSions, in the mapping of micro-· seisms, in the tracing of storms, etc. Outlines of the wide literature concerning surface waves can be found in [2, 9, 40J. Surface waves can be classed as Rayleigh or Love waves, depending on their velocity and polarization: the displacements of particles in Rayleigh waves are parallel, and the displacements in Love waves perpendicular, to the vertical plane containing the direction of propagation (some variation from this polarization is possible close to the source or in the presence of horizontal inhomogeneities in the medium). The present work is devoted to the calculation and investigation of Love waves in a vertically layered medium. The method used is based on the spectral theory of linear differential operators. ' This method is much more effective than previously applied methods based on the approximation of the medium by a set of homogeneous layers.
Author: Giancarlo Dal Moro
Publisher: Elsevier
ISBN: 0128011408
Category : Science
Languages : en
Pages : 253
Get Book Here
Book Description
Seismic Wave Analysis for Near Surface Applications presents the foundational tools necessary to properly analyze surface waves acquired according to both active and passive techniques. Applications range from seismic hazard studies, geotechnical surveys and the exploration of extra-terrestrial bodies. Surface waves have become critical to near-surface geophysics both for geotechnical goals and seismic-hazard studies. Included in this book are the related theories, approaches and applications which the lead editor has assembled from a range of authored contributions carefully selected from the latest developments in research. A unique blend of theory and practice, the book's concepts are based on exhaustive field research conducted over the past decade from the world's leading seismologists and geophysicists. - Edited by a geophysicist with nearly 20 years of experience in research, consulting, and geoscience software development - Nearly 100 figures, photographs, and examples aid in the understanding of fundamental concepts and techniques - Presents the latest research in seismic wave characteristics and analysis, the fundamentals of signal processing, wave data acquisition and inversion, and the latest developments in horizontal-to-vertical spectral ratio (HVSR) - Each chapter features a real-world case study—13 in all—to bring the book's key principles to life
Author: V.I. Keilis-Borok
Publisher: Springer Science & Business Media
ISBN: 9400908830
Category : Science
Languages : en
Pages : 296
Get Book Here
Book Description
Surface waves form the longest and strongest portion of a seismic record excited by explosions and shallow earthquakes. Traversing areas with diverse geologic structures, they 'absorb' information on the properties of these areas which is best retlected in dispersion, the dependence of velocity on frequency. The other prop erties of these waves - polarization, frequency content, attenuation, azimuthal variation of the amplitude and phase - arc also controlled by the medium between the source and the recording station; some of these are affected by the properties of the source itself and by the conditions around it. In recent years surface wave seismology has become an indispensable part of seismological practice. The maximum amplitude in the surface wave train of virtually every earthquake or major explosion is being measured and used by all national and international seismological surveys in the determination of the most important energy parameter of a seismic source, namely, the magnitude M,. The relationship between M, and the body wave magnitude fI1t, is routinely employed in identification of underground nuclear explosions. Surface waves of hundreds of earthquakes recorded every year are being analysed to estimate the seismic moment tensor of earthquake sources, to determine the periods of free oscillations of the Earth, to construct regional dispersion curves from which in turn the crustal and upper mantle structure in various areas is derived, and to evaluate the dissipative parameters of the mantle material.
Author: United States. Department of State. Panel on Seismic Improvement
Publisher:
ISBN:
Category : Explosions
Languages : en
Pages : 236
Get Book Here
Book Description
Author: Sebastiano Foti
Publisher: CRC Press
ISBN: 0415678765
Category : Technology & Engineering
Languages : en
Pages : 492
Get Book Here
Book Description
Develop a Greater Understanding of How and Why Surface Wave Testing Works Using examples and case studies directly drawn from the authors’ experience, Surface Wave Methods for Near-Surface Site Characterization addresses both the experimental and theoretical aspects of surface wave propagation in both forward and inverse modeling. This book accents the key facets associated with surface wave testing for near-surface site characterization. It clearly outlines the basic principles, the theoretical framework and the practical implementation of surface wave analysis. In addition, it also describes in detail the equipment and measuring devices, acquisition techniques, signal processing, forward and inverse modeling theories, and testing protocols that form the basis of modern surface wave techniques. Review Examples of Typical Applications for This Geophysical Technique Divided into eight chapters, the book explains surface wave testing principles from data measurement to interpretation. It effectively integrates several examples and case studies illustrating how different ground conditions and geological settings may influence the interpretation of data measurements. The authors accurately describe each phase of testing in addition to the guidelines for correctly performing and interpreting results. They present variants of the test within a consistent framework to facilitate comparisons, and include an in-depth discussion of the uncertainties arising at each stage of surface wave testing. Provides a comprehensive and in-depth treatment of all the steps involved in surface wave testing Discusses surface wave methods and their applications in various geotechnical conditions and geological settings Explains how surface wave measurements can be used to estimate both stiffness and dissipative properties of the ground Addresses the issue of uncertainty, which is often an overlooked problem in surface wave testing Includes examples with comparative analysis using different processing techniques and inversion algorithms Outlines advanced applications of surface wave testing such as joint inversion, underwater investigation, and Love wave analysis Written for geotechnical engineers, engineering seismologists, geophysicists, and researchers, Surface Wave Methods for Near-Surface Site Characterization offers practical guidance, and presents a thorough understanding of the basic concepts.
