TY - JOUR

T1 - Seismic traveltime inversion based on tomographic equation without integral terms

AU - Huang, Guangnan

AU - Zhou, Bing

AU - Li, Hongxing

AU - Nobes, David C.

N1 - Funding Information:
The authors greatly appreciate Dr. Jonathan B. Ajo-Franklin in Lawrence Berkeley National Laboratory kindly provided the first-arrival data, and coordinates of shots and geophones in the real data test section. This research is jointly supported by the National Natural Science Foundation of China (41504095, 41364004), and Foundation of Department of Education in Jiangxi Province (GJJ160570).
Publisher Copyright:
© 2017 Elsevier Ltd

PY - 2017/7/1

Y1 - 2017/7/1

N2 - The Jacobian matrix in the seismic traveltime tomographic equations usually contains several integral terms. These integral expressions not only greatly increase the computational complexity of seismic traveltime tomography, but also increase difficulty for programming these expressions. Therefore, if these integral expressions of the Jacobian matrix can be eliminated, the program of seismic traveltime tomography can be greatly simplified. In order to solve the computational complexity of the traditional seismic traveltime tomography, we found an anisotropic seismic traveltime tomographic equation which does not contain integral expressions. Then, it is degenerated into an isotropic seismic traveltime tomographic equation. In order to verify the effectiveness of this seismic traveltime tomographic equation based on the node network, a program has been coded to execute seismic traveltime inversion. For a crosswell checkerboard velocity model, the same results are obtained by this proposed tomographic method and the traditional method (with integral terms). Besides, two undulating topography velocity models are used as testing models. Numerical simulation results show that this proposed tomographic method can achieve good tomograms. Finally, this proposed tomographic method is used to investigate near surface velocity distribution near a power plant. Tomogram indicates that contaminated liquid diffuses and aggregates along strata at a certain depth. And velocity is lower near pollutant source than that away from it.

AB - The Jacobian matrix in the seismic traveltime tomographic equations usually contains several integral terms. These integral expressions not only greatly increase the computational complexity of seismic traveltime tomography, but also increase difficulty for programming these expressions. Therefore, if these integral expressions of the Jacobian matrix can be eliminated, the program of seismic traveltime tomography can be greatly simplified. In order to solve the computational complexity of the traditional seismic traveltime tomography, we found an anisotropic seismic traveltime tomographic equation which does not contain integral expressions. Then, it is degenerated into an isotropic seismic traveltime tomographic equation. In order to verify the effectiveness of this seismic traveltime tomographic equation based on the node network, a program has been coded to execute seismic traveltime inversion. For a crosswell checkerboard velocity model, the same results are obtained by this proposed tomographic method and the traditional method (with integral terms). Besides, two undulating topography velocity models are used as testing models. Numerical simulation results show that this proposed tomographic method can achieve good tomograms. Finally, this proposed tomographic method is used to investigate near surface velocity distribution near a power plant. Tomogram indicates that contaminated liquid diffuses and aggregates along strata at a certain depth. And velocity is lower near pollutant source than that away from it.

KW - Checkerboard model

KW - Model parameterization

KW - Seismic traveltime tomography

KW - Velocity inversion

UR - http://www.scopus.com/inward/record.url?scp=85017295887&partnerID=8YFLogxK

U2 - 10.1016/j.cageo.2017.04.002

DO - 10.1016/j.cageo.2017.04.002

M3 - Article

AN - SCOPUS:85017295887

SN - 0098-3004

VL - 104

SP - 29

EP - 34

JO - Computers and Geosciences

JF - Computers and Geosciences

ER -