Near-surface Characterization Via Seismic Surface-wave Inversion

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (868 download)

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Book Synopsis Near-surface Characterization Via Seismic Surface-wave Inversion by : Soumya Roy

Download or read book Near-surface Characterization Via Seismic Surface-wave Inversion written by Soumya Roy and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Characterization of the near-surface is important in identifying shallow properties and structures. In this dissertation, special emphasis is placed on estimating near-surface shear (S)-wave velocities (V_S) which can be used for exploration seismology as well as geotechnical purposes; and even for planetary studies. A frequency-based surface-wave (Rayleigh-wave or ground-roll) inversion method (MASW: Multichannel Analysis of Surface Waves) has been used to estimate 1D and 2D S-wave velocities. The method has been applied on varied seismic datasets related to numerical modeling, physical modeling, and field surveys. The field seismic datasets are from different geological settings and geographical locations: 1) La Marque, Texas, 2) Barringer (Meteor) Crater, Arizona, 3) YBRA field camp, Montana, 4) Hockley fault survey, Texas, and 5) Bradford, Pennsylvania. Estimated S-wave velocities range from as low as 100-300 m/s (La Marque, Hockley) to as high as 3400-3500 m/s (physical model: blank glass block). For the Meteor Crater survey, an unconsolidated near-surface structure (ejecta-blanket) and its thinning thickness trend (thickness decreasing from 20 m to 5 m) has been successfully identified using 2D V_S structure (400-1200 m/s). The depths of investigation for S-wave velocities vary from only 10 m (Hockley survey) to 180 m (Bradford survey) depending on acquisition geometries and source types. Apart from the identification of geological structures; S-wave velocities have been used to calculate S-wave statics and predict densities. The long-wavelength S-wave statics have been calculated for Bradford and Meteor Crater surveys. The densities have been successfully predicted from V_S for modeling experiments and field data (Bradford and YBRA surveys). All predicted densities are consistent with known values with a maximum error of 6%. The effect of lateral heterogeneity on MASW has also been evaluated using different numerical and physical models (dipping layers varying from 10℗ð to 90℗ð). MASW works well for gentle heterogeneity but provides smeared velocity structures for sharp heterogeneities (physical model experiment and Hockley fault survey). A basic full-waveform inversion scheme has been applied on a numerical model with a vertical interface (i.e. 90℗ð dip) showing its potential to handle lateral heterogeneity problems.

Surface Wave Analysis for Near Surface Applications

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Publisher : Elsevier
ISBN 13 : 0128011408
Total Pages : 253 pages
Book Rating : 4.1/5 (28 download)

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Book Synopsis Surface Wave Analysis for Near Surface Applications by : Giancarlo Dal Moro

Download or read book Surface Wave Analysis for Near Surface Applications written by Giancarlo Dal Moro and published by Elsevier. This book was released on 2014-11-04 with total page 253 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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

Surface Wave Methods for Near-Surface Site Characterization

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Publisher : CRC Press
ISBN 13 : 0415678765
Total Pages : 492 pages
Book Rating : 4.4/5 (156 download)

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Book Synopsis Surface Wave Methods for Near-Surface Site Characterization by : Sebastiano Foti

Download or read book Surface Wave Methods for Near-Surface Site Characterization written by Sebastiano Foti and published by CRC Press. This book was released on 2014-08-21 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Advancements in 1D and 2D Near-surface Seismic Site Characterization Using Surface Waves and Full Waveform Inversion

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (137 download)

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Book Synopsis Advancements in 1D and 2D Near-surface Seismic Site Characterization Using Surface Waves and Full Waveform Inversion by : Michael Benjamin Schutt Yust

Download or read book Advancements in 1D and 2D Near-surface Seismic Site Characterization Using Surface Waves and Full Waveform Inversion written by Michael Benjamin Schutt Yust and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic site characterization is a critical part of understanding earthquake hazards in geotechnical engineering. This is often accomplished through various invasive and non-invasive methods for measuring shear-wave velocity (Vs) in-situ, as it is directly related to small-strain shear modulus. For civil engineering applications, the seismic conditions of the near surface (top 30 m) are of particular interest. Surface wave testing has become the tool of choice for many engineers due to its flexibility, efficiency, and ability to characterize a wide variety of subsurface conditions. Surface wave testing is also particularly well suited to near-surface imaging due to the prevalence of surface waves within the elastic wavefield at shallow depths. Surface wave testing, however, is not without limitations. Inversion of surface wave dispersion data is ill-posed and non-unique, meaning that when it is performed rigorously with full consideration of epistemic uncertainty, a potentially large number of reasonable and different 1D Vs profiles are produced. This presents a challenge of evaluating which profiles should be used for further analysis or design. Additionally, engineers often desire information about the lateral variability of seismic parameters in the subsurface, but the inherently 1D nature of the processing and inversion techniques used in surface wave testing make acquiring this information challenging. Evaluation of lateral variability is generally accomplished through multiple individual 1D surface wave analyses across the site, providing only pseudo-2D information. This also introduces a new challenge: how to collect the large amount of experimental data required for multiple analyses as the efficiency of traditional surface wave acquisition is limited by the need to physically move geophone arrays with limited numbers of sensors. This dissertation discusses these challenges and presents potential solutions through the application of the DeltaVs method, distributed acoustic sensing, and full waveform inversion

Geophysical Characterization of Sites

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Publisher : Science Publishers
ISBN 13 :
Total Pages : 160 pages
Book Rating : 4.F/5 ( download)

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Book Synopsis Geophysical Characterization of Sites by : Richard D. Woods

Download or read book Geophysical Characterization of Sites written by Richard D. Woods and published by Science Publishers. This book was released on 1994 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Land Seismic Case Studies for Near-Surface Modeling and Subsurface Imaging

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Publisher : SEG Books
ISBN 13 : 1560803800
Total Pages : 1056 pages
Book Rating : 4.5/5 (68 download)

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Book Synopsis Land Seismic Case Studies for Near-Surface Modeling and Subsurface Imaging by : Öz Yilmaz

Download or read book Land Seismic Case Studies for Near-Surface Modeling and Subsurface Imaging written by Öz Yilmaz and published by SEG Books. This book was released on 2021-06-30 with total page 1056 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written for practicing geophysicists, “Land Seismic Case Studies for Near-Surface Modeling and Subsurface Imaging” is a comprehensive guide to understanding and interpreting seismic data. The culmination of land seismic data acquisition and processing projects conducted by the author over the last two decades, this book contains more than nearly 800 figures from worldwide case studies—conducted in both 2D and 3D. Beginning with Chapter 1 on seismic characterization of the near-surface, Chapter 2 presents near-surface modeling by traveltime and full-wave inversion, Chapter 3 presents near-surface modeling by imaging, and then Chapter 4 includes detailed case studies for near-surface modeling. Chapter 5 reviews single- and multichannel signal processing of land seismic data with the key objective of removing surface waves and guided waves that are characterized as coherent linear noise. Uncommon seismic data acquisition methods, including large-offset acquisition in thrust belts to capture the large-amplitude supercritical reflections, swath-line acquisition, and joint PP and SH- SH seismic imaging are highlighted in Chapter 6, and Chapter 7 presents image-based rms velocity estimation and discusses the problem of velocity uncertainty. The final two chapters focus exclusively on case studies: 2D in Chapter 8 and 3D in Chapter 9. An outstanding teaching tool, this book includes analysis workflows containing processing steps designed to solve specific problems. Essential for anyone involved in acquisition, processing, and inversion of seismic data, this volume will become the definitive reference for understanding how the variables in seismic acquisition are directly reflected in the data.

Distributed Acoustic Sensing in Geophysics

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Publisher : John Wiley & Sons
ISBN 13 : 1119521793
Total Pages : 324 pages
Book Rating : 4.1/5 (195 download)

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Book Synopsis Distributed Acoustic Sensing in Geophysics by : Yingping Li

Download or read book Distributed Acoustic Sensing in Geophysics written by Yingping Li and published by John Wiley & Sons. This book was released on 2022-01-26 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive handbook on state-of-the-art DAS technology and applications Distributed Acoustic Sensing (DAS) is a technology that records sound and vibration signals along a fiber optic cable. Its advantages of high resolution, continuous, and real-time measurements mean that DAS systems have been rapidly adopted for a range of applications, including hazard mitigation, energy industries, geohydrology, environmental monitoring, and civil engineering. Distributed Acoustic Sensing in Geophysics: Methods and Applications presents experiences from both industry and academia on using DAS in a range of geophysical applications. Volume highlights include: DAS concepts, principles, and measurements Comprehensive review of the historical development of DAS and related technologies DAS applications in hydrocarbon, geothermal, and mining industries DAS applications in seismology DAS applications in environmental and shallow geophysics The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.

The Microtremor Survey Method

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Publisher : SEG Books
ISBN 13 : 1560801204
Total Pages : 150 pages
Book Rating : 4.5/5 (68 download)

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Book Synopsis The Microtremor Survey Method by : Hiroshi Okada

Download or read book The Microtremor Survey Method written by Hiroshi Okada and published by SEG Books. This book was released on 2003 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the nature of the microtremor noise field, the use of appropriate surface arrays of geophones, and the two principal classes of array-processing techniques, high-resolution beamforming and the spatial autocorrelation method (SPAC). This is the first comprehensive textbook of the microtremor survey method written in English.

Principles of Seismology

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Publisher : Cambridge University Press
ISBN 13 : 1107138698
Total Pages : 573 pages
Book Rating : 4.1/5 (71 download)

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Book Synopsis Principles of Seismology by : Agustín Udías Vallina

Download or read book Principles of Seismology written by Agustín Udías Vallina and published by Cambridge University Press. This book was released on 2018 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition features a completely new chapter on digital seismic data processing, numerous examples and 100 problems.

Inversion of Surface Waves in an Oil and Gas Exploration Context

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Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (994 download)

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Book Synopsis Inversion of Surface Waves in an Oil and Gas Exploration Context by : Isabella Masoni

Download or read book Inversion of Surface Waves in an Oil and Gas Exploration Context written by Isabella Masoni and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The characterization of the near surface is an important topic for the oil and gas industry. For land and Ocean Bottom Cable (OBC) acquisitions, weathered or unconsolidated top layers, prominent topography and complex shallow structures may make imaging at target depth very difficult. Energetic and complex surface waves often dominate such recordings, masking the signal and challenging conventional seismic processing. Static corrections and the painstaking removal of surface waves are required to obtain viable exploration information.Yet surface waves, which sample the near surface region, are considered as signal on both the engineering and geotechnical scale as well as the global seismology scale. Their dispersive property is conventionally used in surface wave analysis techniques to obtain local shear velocity depth profiles. But limitations such as the picking of dispersion curves and poor lateral resolution have lead to the proposal of Full Waveform Inversion (FWI) as an alternative high resolution technique. FWI can theoretically be used to explain the complete waveforms recoded in seismograms, but FWI with surface waves has its own set of challenges. A sufficiently accurate initial velocity model is required or otherwise cycle-skipping problems will prevent the inversion to converge.This study investigates alternative misfit functions that can overcome cycle-skipping and decrease the dependence on the initial model required. Computing the data-fitting in different domains such as the frequency-wavenumber (f-k) and frequency-slowness (f-p) domains is proposed for robust FWI, and successful results are achieved with a synthetic dataset, in retrieving lateral shear velocity variations.In the second part of this study a FWI layer stripping strategy, specifically adapted to the physics of surface waves is proposed. The penetration of surface waves is dependent on their wavelength, and therefore on their frequency. High-to-low frequency data is therefore sequentially inverted to update top-to-bottom layer depths of the shear velocity model. In addition, near-to-far offsets are considered to avoid cycle-skipping issues. Results with a synthetic dataset show that this strategy is more successful than conventional multiscale FWI in using surface waves to update the shear velocity model.Finally inversion of surface waves for near surface characterization is attempted on a real dataset at the oil and gas exploration scale. The construction of initial models and the difficulties encountered during FWI with real data are discussed.

Seismic Surface Waves in a Laterally Inhomogeneous Earth

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Publisher : Springer Science & Business Media
ISBN 13 : 9400908830
Total Pages : 296 pages
Book Rating : 4.4/5 (9 download)

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Book Synopsis Seismic Surface Waves in a Laterally Inhomogeneous Earth by : V.I. Keilis-Borok

Download or read book Seismic Surface Waves in a Laterally Inhomogeneous Earth written by V.I. Keilis-Borok and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Near-surface Characterization Using Seismic Refraction and Surface-wave Methods

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Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (135 download)

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Book Synopsis Near-surface Characterization Using Seismic Refraction and Surface-wave Methods by : Khaled Al Dulaijan

Download or read book Near-surface Characterization Using Seismic Refraction and Surface-wave Methods written by Khaled Al Dulaijan and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

The Solution of the Inverse Problem in Geophysical Interpretation

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Publisher : Springer Science & Business Media
ISBN 13 : 1468439626
Total Pages : 371 pages
Book Rating : 4.4/5 (684 download)

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Book Synopsis The Solution of the Inverse Problem in Geophysical Interpretation by : R. Cassinis

Download or read book The Solution of the Inverse Problem in Geophysical Interpretation written by R. Cassinis and published by Springer Science & Business Media. This book was released on 2013-03-13 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: As is apparent from the table of contents, the lectures at the Third Course of the International School of Applied Geophysics, Erice, March 27-April 4, 1980 (the first part of this volume) dealt with several applications of inversion to different geophy sical methods. For every field, the more general lectures come first, followed by those aimed at more specialized objectives. Not all topics are covered and the coverage is not uniform. The seismological section (especially the seismic reflection methods) is the most developed, and this is only partly due to the actual state of the art. Unfortunately, only abstracts are available for two of the lectures. The second part of the volume contains some short notes and contributions presented either by the lecturers themselves or by other participants. They do not necessarily deal with the process of inversion itself but with the preparation and meaning of the data to be inverted or with some original treatments of problems that were discussed in the afternoon sessions. The discussion sessions and the round table that followed the lectures were essential to the success of the Course and to an understanding ot the difterent perspectives of the various specialists. I hope that the group of very brilliant and willing geophysi cists that made the meeting so interesting will stay ~n touch, grow closer, and meet again. Close scientific cooperation among them could contribute much to the "unification" of geophysical science.

Surface Wave Methods for Near-Surface Site Characterization

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Publisher : CRC Press
ISBN 13 : 1482266822
Total Pages : 482 pages
Book Rating : 4.4/5 (822 download)

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Book Synopsis Surface Wave Methods for Near-Surface Site Characterization by : Sebastiano Foti

Download or read book Surface Wave Methods for Near-Surface Site Characterization written by Sebastiano Foti and published by CRC Press. This book was released on 2014-08-21 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: Develop a Greater Understanding of How and Why Surface Wave Testing WorksUsing 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

Inverse Problem Theory and Methods for Model Parameter Estimation

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Publisher : SIAM
ISBN 13 : 9780898717921
Total Pages : 349 pages
Book Rating : 4.7/5 (179 download)

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Book Synopsis Inverse Problem Theory and Methods for Model Parameter Estimation by : Albert Tarantola

Download or read book Inverse Problem Theory and Methods for Model Parameter Estimation written by Albert Tarantola and published by SIAM. This book was released on 2005-01-01 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: While the prediction of observations is a forward problem, the use of actual observations to infer the properties of a model is an inverse problem. Inverse problems are difficult because they may not have a unique solution. The description of uncertainties plays a central role in the theory, which is based on probability theory. This book proposes a general approach that is valid for linear as well as for nonlinear problems. The philosophy is essentially probabilistic and allows the reader to understand the basic difficulties appearing in the resolution of inverse problems. The book attempts to explain how a method of acquisition of information can be applied to actual real-world problems, and many of the arguments are heuristic.

Near-Surface Applied Geophysics

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Publisher : Cambridge University Press
ISBN 13 : 1107354978
Total Pages : 419 pages
Book Rating : 4.1/5 (73 download)

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Book Synopsis Near-Surface Applied Geophysics by : Mark E. Everett

Download or read book Near-Surface Applied Geophysics written by Mark E. Everett and published by Cambridge University Press. This book was released on 2013-04-25 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: Just a few meters below the Earth's surface lie features of great importance, from geological faults which can produce devastating earthquakes, to lost archaeological treasures. This refreshing, up-to-date book explores the foundations of interpretation theory and the latest developments in near-surface techniques, used to complement traditional geophysical methods for deep-exploration targets. Clear but rigorous, the book explains theory and practice in simple physical terms, supported by intermediate-level mathematics. Techniques covered include magnetics, resistivity, seismic reflection and refraction, surface waves, induced polarization, self-potential, electromagnetic induction, ground-penetrating radar, magnetic resonance, interferometry, seismoelectric and more. Sections on data analysis and inverse theory are provided and chapters are illustrated by case studies, giving students and professionals the tools to plan, conduct and analyze a near-surface geophysical survey. This is an important textbook for advanced-undergraduate and graduate students in geophysics and a valuable reference for practising geophysicists, geologists, hydrologists, archaeologists, and civil and geotechnical engineers.

Reducing Uncertainties in the Velocities Determined by Inversion of Phase Velocity Dispersion Curves Using Synthetic Seismograms

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (969 download)

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Book Synopsis Reducing Uncertainties in the Velocities Determined by Inversion of Phase Velocity Dispersion Curves Using Synthetic Seismograms by : Seyed Mehrdad Hosseini

Download or read book Reducing Uncertainties in the Velocities Determined by Inversion of Phase Velocity Dispersion Curves Using Synthetic Seismograms written by Seyed Mehrdad Hosseini and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Characterizing the near-surface shear-wave velocity structure using Rayleigh-wave phase velocity dispersion curves is widespread in the context of reservoir characterization, exploration seismology, earthquake engineering, and geotechnical engineering. This surface seismic approach provides a feasible and low-cost alternative to the borehole measurements. Phase velocity dispersion curves from Rayleigh surface waves are inverted to yield the vertical shear-wave velocity profile. A significant problem with the surface wave inversion is its intrinsic non-uniqueness, and although this problem is widely recognized, there have not been systematic efforts to develop approaches to reduce the pervasive uncertainty that affects the velocity profiles determined by the inversion. Non-uniqueness cannot be easily studied in a nonlinear inverse problem such as Rayleigh-wave inversion and the only way to understand its nature is by numerical investigation which can get computationally expensive and inevitably time consuming. Regarding the variety of the parameters affecting the surface wave inversion and possible non-uniqueness induced by them, a technique should be established which is not controlled by the non-uniqueness that is already affecting the surface wave inversion. An efficient and repeatable technique is proposed and tested to overcome the non-uniqueness problem; multiple inverted shear-wave velocity profiles are used in a wavenumber integration technique to generate synthetic time series resembling the geophone recordings. The similarity between synthetic and observed time series is used as an additional tool along with the similarity between the theoretical and experimental dispersion curves. The proposed method is proven to be effective through synthetic and real world examples. In these examples, the nature of the non-uniqueness is discussed and its existence is shown. Using the proposed technique, inverted velocity profiles are estimated and effectiveness of this technique is evaluated; in the synthetic example, final inverted velocity profile is compared with the initial target velocity model, and in the real world example, final inverted shear-wave velocity profile is compared with the velocity model from independent measurements in a nearby borehole. Real world example shows that it is possible to overcome the non-uniqueness and distinguish the representative velocity profile for the site that also matches well with the borehole measurements.