Seismic waves can be generated by a sudden release of energy such as an earthquake, volcanic eruption, or chemical explosion. Numerical simulation of seismic wave propagation produced by earthquake by using a particle method. Cleaned and raw waveforms are presented in figure 3c. However in engineering seismology, early all work is based upon the pwave. Bean seismology and computational rock physics laboratory, department of geology, university college dublin, dublin, ireland. The finitedifference timedomain method for modeling of. An earthquake is excited at the source x after which the signal spreads out like ripples in a pond when a stone has been dropped into it. Study of theoretical wave propagation in the earth as well as constraints on earth structure and earthquake rupture. The object of modern seismic analysis is to extract. Elastic wave propagation and generation in seismology article in eos transactions american geophysical union 8450 january 2003 with 48 reads how we measure reads. Elastic wave propagation using fully vectorized high order finitedifference algorithms. Numerical modeling of seismic wave propagation in selected.
Theoretical wave propagation berkeley global seismology group. Elastic wave propagation and generation in seismology jose pujol. The first of them, called pwaves, consists of the transmission of compressions and rarefacciones of rock, similar to the propagation of the sound figure a. Simulating seismic wave propagation in 3d elastic media using staggeredgrid finite differences. A compressional wave causes rock particles to oscillate in the direction that the wavefront is propagating. Among the many types of seismic waves, one can make a broad distinction between body waves, which travel through the earth, and surface waves, which travel at the earths surface 4850. Pwaves are a type of elastic wave, also called seismic waves, that can travel through gases as sound waves, solids and liquids, including the earth. Velickovic 2 1 faculty of electronic engineering nis,yugoslavia 2 eiprofessional electronic factory, nis yugoslavia abstract.
Elastic wave propagation and generation in seismology by j. Propagation of elastic waves in layered media by finite difference methods. Unstructured hexahedral mesh generation is a critical part of the modeling process in the spectralelement method sem. I sh waves by rushan wu, shengwen jin, and xiaobi xie abstract the great advantages of oneway propagation methods, such as the generalized screen propagators gsp method, are the fast speed of computation, often. It focuses on the specific case of cartesian geometry as related to local and regional wave propagation on earth and particularly for situations relevant to. Oct 18, 20 elastic wave propagation and generation in seismology by j. Fundamentals of seismic wave propagation by chris chapman covers the mathematical development of asymptotic ray theory for seismic waves. The propagation velocity of seismic waves depends on density and elasticity of the medium as well as the type of wave. A 3d discrete numerical elastic lattice method for seismic.
A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. All seismic motions occurring within a spherically symmetric body which the earth nearly is can fully be described by a superposition of the natural modes of oscillation of that body namely, the. This is an important theory in its own right because explorationists often assume that wave propagation in rocks can be approximated by acoustic theory so that they can simplify their data processing algorithms. The book will therefore be useful to postgraduate students and research workers specialising in seismic wave theory, theoretical seismology, electromagnetic wave theory and other fields of wave propagation theory. To this plethora of choices we now have a new addition by jose pujol, titledelastic wave propagation and generation in seismology. Published by the press syndicate of the university of cambridge the pitt building, trumpington street, cambridge, united kingdom cambridge university press. The aim of this study has been to provide a clear understanding of the micropolar theory and its applications in seismology. Seismic wave propagation and scattering in heterogeneous crustal waveguides using screen propagators. All the previous studies mention above neglected the details of wave generation in fluid during the source time. Buy elastic wave propagation and generation in seismology on. Numerical simulation of seismic wave propagation produced by. The equation of wave propagation in elastic solids are derived by using hookes law and newtons second law of motion. Fundamentals of seismic wave propagation is intended as a text for graduate courses in theoretical seismology, and a reference for all seismologists using numerical modelling methods. Exercises and suggestions for further reading are included in each chapter.
Modeling of tsunami generation and propagation by a. We will show that two types of solutions are possible, corresponding to compressional p and shear s waves, and we will derive the. Elastic wave propagation and generation in seismology seismology has complementary observational and theoretical components, and a thorough understanding of the observations requires a sound theoretical background. This book focuses on recent developments in the area of seismic wave propagation and scattering through the randomly heterogeneous structure of the earth, with emphasis on the lithosphere. Modeling of tsunami generation and propagation by a spreading. Seismic waves can be generated by a sudden release of energy such as an earthquake. It is not the task of the new manual of seismological observatory practice nmsop, to. The transient wave generation due to the coupling between the seafloor motion and the free surface has been considered by a few authors only. Mathematical foundation of elastic wave propagation. The seismic wave equation using the stress and strain theory developed in the previous chapter, we now construct and solve the seismic wave equation for elastic wave propagation in a uniform whole space. Numerical simulation of seismic wave propagation produced. The particle spacing is set to 10 m, and time spacing is 1 ms.
Modeling of seismic wave propagation at the scale of the. Seismic wave propagation and scattering in the heterogeneous. Simulating seismic wave propagation in 3d elastic media using staggeredgrid finite differences robert w. For the numerical simulation of 2d earthquake dynamics, the spectral boundary integral equation code bimat is well suited for planar faults in homogeneous and bimaterial media, and the spectral element code sem2dpack is well suited for nonplanar faults in heterogeneous or nonlinear media. Chapman, ch fundamentals of seismic wave propagation, cambridge univer sity press. Surface waves which propagate along boundaries between materials such as the airearth interface. The target readers of the new texts range from beginner through intermediate to more advanced, although all have been attempts to improve upon what is now considered standard convention in quantitative seismology. Propagation of elastic waves in layered media by finite.
Advances in modelling and inversion of seismic wave propagation. The development of numerical schemes is of great importance in seismology to provide quantitative information for earthquake disaster prevention and mitigation, such as the simulation of earthquake generation, the estimation of ground shaking. Seismic wave propagation and modelling in poroelastic. Advances in modelling and inversion of seismic wave. Jose pujol is the author of elastic wave propagation and generation in seismology 3. Surface wave seismic wave seismic tomography eikonal equation international seismologieal centre these keywords were added by machine and not by the authors. This propagation of energy is a type of wave motion. Advances in modelling and inversion of seismic wave propagation v. An interesting application of surface wave seismology is related to the offshore seismic prospecting for oil and gas. Wave propagation methods become popular techniques in the evaluation of stiffness of geomaterials and process monitoring both in the laboratory and in the field richart et al. We test hpm using the classic lamb problem as shown in fig. It will also be valuable to researchers in academic and industrial seismology. Codes for wave propagation and earthquake dynamics.
The second type, or waves s, consists of wave propagation of shear, where the particles move in a direction perpendicular to the direction of propagation of the disturbance figure b. Gen erally, this holds for the displacement of waves from a point source. Let us first consider the computational costs of accounting for coupling between each pair of modes, for each sourcereceiver path, as described above. This first video shows the concept of a travelling seismic wave in its very simplest form. Seismology and the earths deep interior elasticity and seismic waves linearlinear and nonlinear stress and strainand nonlinear stress and strain stress vs. In this representation, the displacement is the sum of the. Comparison of numerical methods for seismic wave propagation and source dynamics the spice code validation peter moczo 1,2. Correlation of seismic pwave velocities with engineering. Numerical modeling of seismic wave propagation in selected anisotropic media by. For wave propagation problems assuming linear elasticity is usually sufficient. Simulating seismic wave propagation in 3d elastic media using. Wave propagation methods for determining stiffness of.
Propagation of elastic waves in layered media by finite difference methods z. Unescoioc great waves tsunamis are caused by static displacements. Subjected to a p wave, particles move in the same direction that the wave is moving in, which is the direction that the energy is traveling in, and is sometimes called the direction of wave propagation. The waves are trapped in the upper layer and the particle motion is parallel to the free surface and perpendicular to the direction of propagation. Pwaves are produced by earthquakes and re corded by seismographs. We shall derive the equations for two types of body waves that are of interest in exploration seismology the compressional wave for which the displacement is in the direction of propagation and the shear wave for which the displacement is in the direction perpendicular to the direction of propagation. Table 1 summarizes the existing wave propagation methods used by the geoengineering community in the u. Mathematical foundation of elastic wave propagation seg wiki. We shall derive the equations for two types of body waves that are of interest in exploration seismology the compressional wave for which the. Both longitudinal and transverse elastic waves can propagate in solid media. Physics of acoustic wave propagation the theory of acoustic wave propagation is now described.
Pujol, elastic wave propagation and generation in seismology. Born approximation, and applying it to global and regional tomography. Biots theory identifies the presence of three different types of waves in a fluidsaturated porous medium, namely the classic fast p wave, the second slow p wave and the shear wave. This page intentionally left blank elastic wave propagation and generation in seismology seismology has complementary observational and theoretical components, and a thorough understanding of the observations requires a sound theoretical background. In particular, the properties of plane and spherical waves at interfaces are described. Seismic wave propagation and scattering in heterogeneous.
Download citation elastic wave propagation and generation in seismology bridging the gap between introductory textbooks and advanced monographs, this. Kennett title page contents jj ii j i page 8 of 497 back full screen close quit rs s e anu preface the primary sources of data in seismology are seismic records at the earths surface of natural or manmade events. Seismic wave propagation and modelling in poroelastic media. Buy elastic wave propagation and generation in seismology on free shipping on qualified orders. Since the number of modes of frequency less than the corner frequency of the seismogram of interest is proportional to the square of the wavenumber lengthscale of the. The finitedifference method is a robust numerical method applicable to structurally complex media.
The presentation combines information from many sources to present a coherent introduction to the theory of scattering in acoustic and elastic materials and. A 3d discrete numerical elastic lattice method for seismic wave propagation in heterogeneous media with topography gareth s. Elastic wave propagation and generation in seismology. Due to the high average efficiency of surface wave propagation across continents, surface. The character of the propagation effects depends on the nature of the elastic parameter. In classical seismology, the earth is modeled as a sequence of uniform horizontal layers or spherical shells having different elastic properties and one determines these properties from travel times and dispersion of seismic waves. This process is experimental and the keywords may be updated as the learning algorithm improves.
Jose pujol author of elastic wave propagation and generation. Seismic wave propagation in stratified media oapen. Within its elastic range the behavior of the earth material can be described by. Example results of wave propagation modeling in anisotropic mediaale sniak, tdanek. The book covers strain, stress, propagation of body and surface waves in simple models halfspaces and the layer over a halfspace, ray theory for p and s waves including amplitude equations, near and far fields generated by moment tensor sources in infinite media, and attenuation and the mathematics of causality. Seismic wave propagation and scattering in the heterogeneous earth. In this section, we use uniform arrangement of particles to represent a flat surface. It focuses on the specific case of cartesian geometry as related to local and regional wave propagation on earth and particularly for situations relevant to the petroleum industry. Wave propagation based on a lecture by james mori of the earthquake hazards division. A principal difference among p, sv, and sh wavefields is the manner in which they cause rock particles to oscillate. At the scale of an alluvial basin, the analysis of seismic wave propagation is a complex problem involving as various phenomena as. A model of surface wave propagation in a transversely isotropic elastic solid layer lying between a homogeneous liquid layer and liquid saturated porous anisotropic half space has been considered.
Body waves s waves secondary waves it is slower than a p wave and can only move through solid rock, not through any liquid medium. Seismic wave propagation and earth models gfzpublic. Micropolar modelling of rotational waves in seismology. One of the reasons is that it is commonly assumed that the source details are not important. Seismic wave propagation and seismic tomography springerlink. Theoretical wave propagation berkeley global seismology. Seismic wave fields are recorded by a seismometer, hydrophone in water, or accelerometer. A seismic wave is a mechanical disturbance or energy packet that can propagate from point to point in the earth. Fullwave field modelling is a powerful tool of seismic exploration and seismology.