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Dynamic ray tracing and traveltime corrections for global seismic tomography

Yue Tian, S.-H. Hung, Guust Nolet, Raffaella Montelli, F.A. Dahlen
2007 Journal of Computational Physics  
The numerical precisions of kinematic and dynamic ray tracing are optimized to produce traveltime errors under 0.1 s, which is well below the data uncertainty in global seismology.  ...  We present a dynamic ray tracing program for a spherically symmetric Earth that may be used to compute Fréchet kernels for traveltime and amplitude anomalies at finite frequency.  ...  Acknowledgments We thank Ignace Loris for discussion. Yue Tian was supported by the National Science Foundation under grant number EAR0309298.  ... 
doi:10.1016/j.jcp.2007.04.025 fatcat:5kwil5jtffay5aqo632rt4cqnm

Seismic tomography: A window into deep Earth

N. Rawlinson, S. Pozgay, S. Fishwick
2010 Physics of the Earth and Planetary Interiors  
The relative merits of local versus global parameterization, ray tracing versus wavefront tracking, backprojection versus gradient based inversion and synthetic testing versus model covariance are explored  ...  Several practical applications of seismic tomography, including body wave traveltime, attenuation and surface waveform, are presented in order to reinforce prior discussion of theory.  ...  Acknowledgements Guust Nolet, George Helffrich and an anonymous reviewer are thanked for their constructive comments which substantially improved the paper.  ... 
doi:10.1016/j.pepi.2009.10.002 fatcat:kqzlgj2qhvbxheewjydllf5fei

Integrated seismic tomography and ground-penetrating radar (GPR) for the high-resolution study of burial mounds (tumuli)

E. Forte, M. Pipan
2008 Journal of Archaeological Science  
We implemented an integrated seismic tomography and georadar (STG) technique to perform high-resolution imaging and characterization of tumuli (burial mounds).  ...  We completed two transmission seismic tomography measurements, at present ground level and at 1.5 m elevation, with a 24channel seismograph and 15 angular separation between geophones.  ...  Marco Carnelli for the help during data acquisition and processing and to Dr. Elena Barinova for assistance with archaeological literature.  ... 
doi:10.1016/j.jas.2008.04.024 fatcat:3kxjcklhrvahffwu5y7oeskjgy

Seismic traveltime inversion of 3D velocity model with triangulated interfaces

Fei Li, Tao Xu, Minghui Zhang, Zhenbo Wu, Chenglong Wu, Zhongjie Zhang, Jiwen Teng
2013 Earthquake Science  
The damped least squares method is employed in seismic traveltime inversion, which includes the partial derivatives of traveltime with respect to the depths of nodes in the triangulated interfaces and  ...  We implement a segmentally iterative ray tracer to calculate traveltimes in the 3D heterogeneous block models.  ...  Xi Zhang, Haiqiang Lan and Minling Wang for their constructive comments and suggestions to improve the quality of this work.  ... 
doi:10.1007/s11589-013-0025-0 fatcat:4k2allb67vagbkt26pwxynnoxe

Multiarrival wavefront tracking and its applications

J. Hauser, M. Sambridge, N. Rawlinson
2008 Geochemistry Geophysics Geosystems  
For studies at local and regional scales (e.g., local earthquake/teleseismic tomography), the focus has largely been on first arrivals, with numerous ray-and grid-based schemes developed for their calculation  ...  The idea is to represent the wavefront as a set of points in reduced phase space and use local ray tracing and interpolation to advance the wavefront in a series of time steps.  ...  Kendall and an anonymous reviewer are thanked for their insightful comments, which substantially improved the paper.  ... 
doi:10.1029/2008gc002069 fatcat:a5m4bdgjprhaloo2s5kam3ln74

SEISMIC TRAVELTIME TOMOGRAPHY OF THE CRUST AND LITHOSPHERE [chapter]

N. Rawlinson, M. Sambridge
2003 Advances in Geophysics  
ACKNOWLEDGMENTS We thank Fiona Darbyshire for kindly supplying Fig. 29 and Fig. 30 , and Frank Graeber for kindly supplying Fig. 35, Fig. 36, Fig. 37 and Fig. 38 .  ...  Greg Houseman is thanked for useful discussions on an early version of this work, and an anonymous referee is thanked for constructive comments on the original manuscript.  ...  Source-receiver ray paths and traveltimes are found with a shooting method of ray tracing that uses elements of paraxial ray theory to iteratively correct the ray take-off angle.  ... 
doi:10.1016/s0065-2687(03)46002-0 fatcat:3xrswjxcrrgfzo7b2mkrviilbq

An analysis of SS precursors using spectral-element method seismograms

L. Bai, Y. Zhang, J. Ritsema
2011 Geophysical Journal International  
We find that ray-theoretical corrections account for only 50 per cent of the traveltime variation due to large-scale velocity heterogeneity.  ...  We analyse stacks of spectral-element method waveforms computed for 34 shallow earthquakes and 16 020 globally distributed virtual seismometers.  ...  for seismic tomography.  ... 
doi:10.1111/j.1365-246x.2011.05256.x fatcat:mgl3ai7wkffkbibf47y76us5vy

Joint geodynamical and seismic modelling of the Eifel plume

U. Wüllner, U. R. Christensen, M. Jordan
2006 Geophysical Journal International  
We use ray tracing to calculate synthetic travel times and vary the plume location, radius, temperature and the rate and direction of plate motion in order to fit the observed travel times.  ...  Our results show a fair correlation between synthetic and observed traveltime residuals.  ...  Therefore, calculating the ray paths for the 1-D seismic reference model (1-D ray tracing) may be sufficient.  ... 
doi:10.1111/j.1365-246x.2006.02906.x fatcat:eqiudasrevcx5j5bmmcrk7g4au

A Proterozoic boundary in southern Norway revealed by joint-inversion of P-receiver functions and surface waves

Marianne L. Kolstrup, Valérie Maupin
2013 Precambrian Research  
Dynamic ray tracing and traveltime corrections for 1508–1511.  ...  Long-period body wave traveltimes through the crust: implica- REFERENCES tion for crustal corrections and seismic tomography, Geophys- Aki, K.  ... 
doi:10.1016/j.precamres.2013.10.004 fatcat:cgeywo5icvhufotgzrkflnqgxq

Frequency-dependent effects on global S-wave traveltimes: wavefront-healing, scattering and attenuation

Christophe Zaroli, Eric Debayle, Malcolm Sambridge
2010 Geophysical Journal International  
After correction for physical dispersion due to intrinsic anelastic processes, we observe a residual traveltime dispersion on the order of 1-2 s in the period range of analysis.  ...  S U M M A R Y We present a globally distributed data set of ∼400 000 frequency-dependent SH-wave traveltimes.  ...  Traveltime corrections for global seismic tomography In this study, we aim to build a global data set of multiple-frequency time residuals, suitable for imaging the Earth's mantle structure using inversion  ... 
doi:10.1111/j.1365-246x.2010.04667.x fatcat:gna6dewe6zf47iequvuz6wvkum

Box tomography: localized imaging of remote targets buried in an unknown medium, a step forward for understanding key structures in the deep Earth

Yder Masson, Barbara Romanowicz
2017 Geophysical Journal International  
A C K N O W L E D G E M E N T S We thank two anonymous reviewers and Editor Andrea Morelli for their comments and suggestions.  ...  For the ray tracing, we used the algorithm proposed by Prothero et al. (1988) . A total number of 20 000 rays have been selected for the inversions presented in Fig. 4 .  ...  To construct the data sets needed for the inversions, we traced rays between random pairs of points lying on the outer circle and we selected only the ray paths that go through the imaging box.  ... 
doi:10.1093/gji/ggx141 fatcat:w6l3sx4xxjeglbzfwgfwmc7rn4

Fast and accurate global multiphase arrival tracking: the irregular shortest-path method in a 3-D spherical earth model

Guo-Jiao Huang, Chao-Ying Bai, Stewart Greenhalgh
2013 Geophysical Journal International  
or global traveltime tomography.  ...  The ray tracing results for 49 different kinds of crustal, mantle and core phases show that the maximum absolute traveltime error is less than 0.12 s and the average absolute traveltime error is within  ...  For example, Bijwaard & Spakman (2000) exploited perturbation theory to develop a fast kinematic ray tracing algorithm to trace the first and later arrivals for some global seismic phases.  ... 
doi:10.1093/gji/ggt204 fatcat:2kvpvjo67zbqlpnwnibtt2emta

A successive three-point perturbation method for fast ray tracing in complex 2D and 3D geological models

Tao Xu, Fei Li, Zhenbo Wu, Chenglong Wu, Ergen Gao, Bing Zhou, Zhongjie Zhang, Guoming Xu
2014 Tectonophysics  
This paper presents new 2D and 3D ray-tracing methods that can be applied to traveltime and ray path computations for transmitted, reflected and turning seismic waves in complex geologic models.  ...  The new ray-tracing scheme combines segmentally iterative ray tracing (SIRT) and pseudo-bending methods to address both stratified and arbitrarily shaped block models.  ...  Hrubcova from the Geophysical Institute, Academy of Sciences of the Czech Republic, for providing the Bohemian Massif velocity model for method comparison. Prof. Fuqin Zhang and Dr.  ... 
doi:10.1016/j.tecto.2014.02.012 fatcat:fezwnsd66zgvpflkhsdlkb6p2i

High resolution upper mantle discontinuity images across the Pacific Ocean from SS precursors using local slant stack filters

Zhao Zheng, Sergi Ventosa, Barbara Romanowicz
2015 Geophysical Journal International  
We show that these filters are a powerful tool for extracting the weak yet coherent SS precursor signals while removing interfering seismic phases as well as random noise, yielding robust precursor traveltime  ...  We discuss correlations observed between our discontinuity images and several fine-scale heterogeneities revealed by mantle shear wave tomography in the vicinity of Hawaii and the Pacific Superswell.  ...  These traveltime corrections are calculated cumulatively along each ray path in the 1-D Earth model.  ... 
doi:10.1093/gji/ggv118 fatcat:7ldwcnp76ran5mowzcd2lm3dua

SEISMIC TRAVELTIME TOMOGRAPHY IN THE DOM JOÃO FIELD, RECÔNCAVO BASIN, BRAZIL

Naiane Pereira de Oliveira, Amin Bassrei
2015 Revista Brasileira de Geofisica  
Acoustic ray tracing for the computation of traveltimes was used for forward modeling, and the conjugate gradient algorithm with regularization through derivative matrices was used as the inverse procedure  ...  The results showed that traveltime tomography is feasible for the characterization of reservoirs with a high rate of vertical change, similar to the Dom Jo˜ao Field.Keywords: traveltime tomography, seismic  ...  In Exploration Seismology, the tomographic technique is grouped into two classes: traveltime tomography, which takes into account only the traveltimes between the sources and the receivers, and dynamic  ... 
doi:10.22564/rbgf.v33i1.604 fatcat:fmqvvv3lrfdozg3pbnktqgj26m
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