Wave-equation-based travel-time seismic tomography – Part 1: Method

Abstract. In this paper, we propose a wave-equation-based travel-time seismic tomography method with a detailed description of its step-by-step process. First, a linear relationship between the travel-time residual Δt = Tobs–Tsyn and the relative velocity perturbation δ c(x)/c(x) connected by a finite-frequency travel-time sensitivity kernel K(x) is theoretically derived using the adjoint method. To accurately calculate the travel-time residual Δt, two automatic arrival-time picking techniques including the envelop energy ratio method and the combined ray and cross-correlation method are then developed to compute the arrival times Tsyn for synthetic seismograms. The arrival times Tobs of observed seismograms are usually determined by manual hand picking in real applications. Travel-time sensitivity kernel K(x) is constructed by convolving a~forward wavefield u(t,x) with an adjoint wavefield q(t,x). The calculations of synthetic seismograms and sensitivity kernels rely on forward modeling. To make it computationally feasible for tomographic problems involving a large number of seismic records, the forward problem is solved in the two-dimensional (2-D) vertical plane passing through the source and the receiver by a high-order central difference method. The final model is parameterized on 3-D regular grid (inversion) nodes with variable spacings, while model values on each 2-D forward modeling node are linearly interpolated by the values at its eight surrounding 3-D inversion grid nodes. Finally, the tomographic inverse problem is formulated as a regularized optimization problem, which can be iteratively solved by either the LSQR solver or a~nonlinear conjugate-gradient method. To provide some insights into future 3-D tomographic inversions, Frechet kernels for different seismic phases are also demonstrated in this study.

[1]  Kim B. Olsen,et al.  Frechet Kernels for Imaging Regional Earth Structure Based on Three-Dimensional Reference Models , 2005 .

[2]  Carl Tape,et al.  Adjoint Tomography of the Southern California Crust , 2009, Science.

[3]  Dapeng Zhao,et al.  Multiscale seismic tomography and mantle dynamics , 2009 .

[4]  Andreas Fichtner,et al.  Resolution analysis in full waveform inversion , 2011 .

[5]  E. Engdahl,et al.  Finite-Frequency Tomography Reveals a Variety of Plumes in the Mantle , 2004, Science.

[6]  John C. Bancroft,et al.  Time Picking on Noisy Microseismograms , 2010 .

[7]  E. Engdahl,et al.  A new global model for P wave speed variations in Earth's mantle , 2008 .

[8]  L. Chiao,et al.  Imaging seismic velocity structure beneath the Iceland hot spot: A finite frequency approach , 2004 .

[9]  Bradford H. Hager,et al.  Large‐scale heterogeneities in the lower mantle , 1977 .

[10]  Qinya Liu,et al.  Tomography, Adjoint Methods, Time-Reversal, and Banana-Doughnut Kernels , 2004 .

[11]  B. Kennett,et al.  Traveltimes for global earthquake location and phase identification , 1991 .

[12]  Jeroen Tromp,et al.  Finite-frequency sensitivity kernels for global seismic wave propagation based upon adjoint methods , 2008 .

[13]  N. Umino,et al.  Imaging the subducting slabs and mantle upwelling under the Japan Islands , 2012 .

[14]  D. Komatitsch,et al.  A 3‐D spectral‐element and frequency‐wave number hybrid method for high‐resolution seismic array imaging , 2014 .

[15]  Maarten V. de Hoop,et al.  On sensitivity kernels for ‘wave-equation’ transmission tomography , 2005 .

[16]  D. Komatitsch,et al.  Spectral-element simulations of global seismic wave propagation: II. Three-dimensional models, oceans, rotation and self-gravitation , 2002 .

[17]  Jeroen Tromp,et al.  Spectral-element moment tensor inversions for earthquakes in Southern California , 2004 .

[18]  G. Nolet,et al.  Traveltimes and amplitudes of seismic waves: a re-assessment , 2013 .

[19]  A. Tarantola Inversion of seismic reflection data in the acoustic approximation , 1984 .

[20]  Manfred Baer,et al.  An automatic phase picker for local and teleseismic events , 1987 .

[21]  D. Komatitsch,et al.  Simulations of Ground Motion in the Los Angeles Basin Based upon the Spectral-Element Method , 2004 .

[22]  Qinya Liu,et al.  Seismic imaging: From classical to adjoint tomography , 2012 .

[23]  Dong-Joo Min,et al.  Frequency-domain elastic full waveform inversion for VTI media , 2010 .

[24]  Dinghui Yang,et al.  A central difference method with low numerical dispersion for solving the scalar wave equation , 2012 .

[25]  B. Romanowicz,et al.  Finite frequency effects on global S diffracted traveltimes , 2009 .

[26]  Paul G. Richards,et al.  Quantitative Seismology: Theory and Methods , 1980 .

[27]  Thomas H. Jordan,et al.  Full 3D Tomography for the Crustal Structure of the Los Angeles Region , 2007 .

[28]  S. Operto,et al.  3D finite-difference frequency-domain modeling of visco-acoustic wave propagation using a massively parallel direct solver: A feasibility study , 2007 .

[29]  D. Komatitsch,et al.  Spectral-element simulations of global seismic wave propagation—I. Validation , 2002 .

[30]  Dinghui Yang,et al.  Tomography of the 1995 Kobe earthquake area: comparison of finite‐frequency and ray approaches , 2011 .

[31]  Jouni Saari Automated phase picker and source location algorithm for local distances using a single three-component seismic station , 1991 .

[32]  Yang Luo Seismic imaging and inversion based on spectral-element and adjoint methods , 2012 .

[33]  Guust Nolet,et al.  Computing traveltime and amplitude sensitivity kernels in finite-frequency tomography , 2007, J. Comput. Phys..

[34]  Jeroen Tromp,et al.  Supplementary information for Structure of the European Upper Mantle revealed by adjoint tomography , 2012 .

[35]  Barbara Romanowicz Seismic Tomography of the Earth's Mantle , 1991 .

[36]  B. Borchers,et al.  Nonlinear Inverse Problems , 2019, Parameter Estimation and Inverse Problems.

[37]  J. Hornung,et al.  Assessing accuracy of gas-driven permeability measurements: a comparative study of diverse Hassler-cell and probe permeameter devices , 2013 .

[38]  R. Shipp,et al.  Seismic waveform inversion in the frequency domain, Part 2: Fault delineation in sediments using crosshole data , 1999 .

[39]  Carl Tape,et al.  Finite‐frequency tomography using adjoint methods—Methodology and examples using membrane surface waves , 2007 .

[40]  Nicholas Rawlinson,et al.  Seismic tomography: a window into deep Earth , 2010 .

[41]  T. Jordan,et al.  Structural sensitivities of finite-frequency seismic waves: a full-wave approach , 2006 .

[42]  A. Fichtner,et al.  The Iceland-Jan Mayen plume system and its impact on mantle dynamics in the North Atlantic region: Evidence from full-waveform inversion , 2013 .

[43]  Carl Tape,et al.  Seismic tomography of the southern California crust based on spectral‐element and adjoint methods , 2010 .

[44]  J. Virieux,et al.  Finite‐frequency tomography in a crustal environment: Application to the western part of the Gulf of Corinth , 2008 .

[45]  Guust Nolet,et al.  Comment on ‘On sensitivity kernels for ‘wave-equation’ transmission tomography’ by de Hoop and van der Hilst , 2005 .

[46]  Akira Hasegawa,et al.  Tomographic imaging of P and S wave velocity structure beneath northeastern Japan , 1992 .

[47]  Jeroen Tromp,et al.  A perfectly matched layer absorbing boundary condition for the second-order seismic wave equation , 2003 .

[48]  Clifford H. Thurber,et al.  Parameter estimation and inverse problems (paperback) , 2012 .

[49]  Gerard T. Schuster,et al.  Wave equation inversion of skeletalized geophysical data , 1991 .

[50]  J. Lei,et al.  Local earthquake reflection tomography of the Landers aftershock area , 2005 .

[51]  Guust Nolet,et al.  Fréchet kernels for finite-frequency traveltimes—I. Theory , 2000 .

[52]  Dimitri Komatitsch,et al.  Accelerating a three-dimensional finite-difference wave propagation code using GPU graphics cards , 2010 .

[53]  Dinghui Yang,et al.  Tomography of the 2011 Iwaki earthquake (M 7.0) and Fukushima nuclear power plant area , 2011 .

[54]  Dapeng Zhao,et al.  Tomography and Dynamics of Western-Pacific Subduction Zones , 2012 .

[55]  D. Komatitsch,et al.  Introduction to the spectral element method for three-dimensional seismic wave propagation , 1999 .

[56]  Robert W. Graves,et al.  Simulating seismic wave propagation in 3D elastic media using staggered-grid finite differences , 1996, Bulletin of the Seismological Society of America.

[57]  Michael A. Saunders,et al.  LSQR: An Algorithm for Sparse Linear Equations and Sparse Least Squares , 1982, TOMS.

[58]  Shu-Huei Hung,et al.  A data‐adaptive, multiscale approach of finite‐frequency, traveltime tomography with special reference to P and S wave data from central Tibet , 2011 .

[59]  Andreas Fichtner,et al.  Simulation and Inversion of Seismic Wave Propagation on Continental Scales Based on a Spectral - Element Method , 2009 .

[60]  Thomas H. Jordan,et al.  Three‐dimensional Fréchet differential kernels for seismicdelay times , 2000 .

[61]  Keiiti Aki,et al.  Determination of three‐dimensional velocity anomalies under a seismic array using first P arrival times from local earthquakes: 1. A homogeneous initial model , 1976 .

[62]  Jean Virieux,et al.  Crustal seismic imaging from multifold ocean bottom seismometer data by frequency domain full waveform tomography: Application to the eastern Nankai trough , 2006 .

[63]  R. Hilst,et al.  Reply to comment by F.A. Dahlen and G. Nolet on , 2005 .

[64]  Gordon Erlebacher,et al.  High-order finite-element seismic wave propagation modeling with MPI on a large GPU cluster , 2010, J. Comput. Phys..

[65]  T. Jordan,et al.  FAST TRACK PAPER: Full three-dimensional tomography: a comparison between the scattering-integral and adjoint-wavefield methods , 2007 .

[66]  Guust Nolet,et al.  Three-dimensional sensitivity kernels for finite-frequency traveltimes: the banana–doughnut paradox , 1999 .

[67]  Carl Tape,et al.  An automated time-window selection algorithm for seismic tomography , 2009 .

[68]  Peter M. Shearer,et al.  Characterization of global seismograms using an automatic-picking algorithm , 1994, Bulletin of the Seismological Society of America.

[69]  Jean Virieux,et al.  SH-wave propagation in heterogeneous media: velocity-stress finite-difference method , 1984 .

[70]  J. Nocedal Updating Quasi-Newton Matrices With Limited Storage , 1980 .

[71]  Andreas Fichtner,et al.  The adjoint method in seismology: I. Theory , 2006 .

[72]  Dimitri Komatitsch,et al.  High-resolution seismic array imaging based on an SEM-FK hybrid method , 2014 .

[73]  Jeroen Tromp,et al.  Adjoint centroid-moment tensor inversions , 2011 .

[74]  R. Hilst,et al.  Constraining P-wave velocity variations in the upper mantle beneath Southeast Asia , 2006 .

[75]  C. M. Reeves,et al.  Function minimization by conjugate gradients , 1964, Comput. J..

[76]  Malcolm Sambridge,et al.  Seismic tomography with irregular meshes , 2013 .

[77]  Clifford H. Thurber,et al.  Adaptive mesh seismic tomography based on tetrahedral and Voronoi diagrams: Application to Parkfield, California , 2005 .

[78]  F. Coppens,et al.  First arrival picking on common-offset trace collections for automatic estimation of static corrections , 1985 .

[79]  Qinya Liu,et al.  Wave-equation-based travel-time seismic tomography – Part 2: Application to the 1992 Landers earthquake ( M w 7.3) area , 2014 .

[80]  3D Elastic Migration With Topography Based on Spectral-Element and Adjoint Methods , 2012 .

[81]  Clifford H. Thurber,et al.  Earthquake locations and three‐dimensional crustal structure in the Coyote Lake Area, central California , 1983 .

[82]  Walter H. F. Smith,et al.  Free software helps map and display data , 1991 .

[83]  Albert Tarantola,et al.  Inverse problem theory - and methods for model parameter estimation , 2004 .

[84]  Clifford H. Thurber,et al.  Automatic P-Wave Arrival Detection and Picking with Multiscale Wavelet Analysis for Single-Component Recordings , 2003 .

[85]  Jean Virieux,et al.  An overview of full-waveform inversion in exploration geophysics , 2009 .

[86]  J. Nakajima,et al.  Mapping the crustal structure under active volcanoes in central Tohoku, Japan using P and PmP data , 2007 .

[87]  Guust Nolet,et al.  Wavefront healing: a banana–doughnut perspective , 2001 .

[88]  Adam M. Dziewonski,et al.  Mapping the lower mantle: Determination of lateral heterogeneity in P velocity up to degree and order 6 , 1984 .

[89]  J. Tromp,et al.  Finite-Frequency Kernels Based on Adjoint Methods , 2006 .