The analysis and application of simplified two-parameter moveout equation for C-waves in VTI anisotropy media
Li Xiao-Ming1,2, Chen Shuang-Quan1,2, and Li Xiang-Yang1,2,3
1. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China.
2. CNPC Key Laboratory of Geophysical Prospecting, China University of Petroleum, Beijing 102249, China.
3. Edinburgh Anisotropy Project, British Geophysical Survey, Edinburgh EH9 3LA, U.K.
Abstract Several parameters are needed to describe the converted-wave (C-wave) moveout in processing multi-component seismic data, because of asymmetric raypaths and anisotropy. As the number of parameters increases, the converted wave data processing and analysis becomes more complex. This paper develops a new moveout equation with two parameters for C-waves in vertical transverse isotropy (VTI) media. The two parameters are the C-wave stacking velocity (VC2) and the squared velocity ratio (γvti) between the horizontal P-wave velocity and C-wave stacking velocity. The new equation has fewer parameters, but retains the same applicability as previous ones. The applicability of the new equation and the accuracy of the parameter estimation are checked using model and real data. The form of the new equation is the same as that for layered isotropic media. The new equation can simplify the procedure for C-wave processing and parameter estimation in VTI media, and can be applied to real C-wave processing and interpretation. Accurate VC2 and γvti can be deduced from C-wave data alone using the double-scanning method, and the velocity ratio model is suitable for event matching between P- and C-wave data.
The research is sponsored by the National Natural Science Foundation of China (No. 41074080), the National Science and Technology Major Project (No. 2011ZX05019-008), the Science Foundation of China University of Petroleum-Beijing (No. KYJJ2012-05-11), and the PetroChina Innovation Foundation (No. 2012D-5006-0301).
Cite this article:
LI Xiao-Ming,CHEN Shuang-Quan,LI Xiang-Yang. The analysis and application of simplified two-parameter moveout equation for C-waves in VTI anisotropy media[J]. APPLIED GEOPHYSICS, 2013, 10(4): 477-487.
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