Type
ArticleKAUST Department
Earth Science and Engineering ProgramPhysical Science and Engineering (PSE) Division
Seismic Wave Analysis Group
Date
2015-08-19Online Publication Date
2015-08-19Print Publication Date
2015-08-19Permanent link to this record
http://hdl.handle.net/10754/593185
Metadata
Show full item recordAbstract
Extended images obtained from reverse-time migration (RTM) contain information about the accuracy of the velocity field and subsurface illumination at different incidence angles. Here, we evaluate the influence of errors in the anisotropy parameters on the shape of the residual moveout (RMO) in P-wave RTM extended images for VTI (transversely isotropic with a vertical symmetry axis) media. Considering the actual spatial distribution of the zero-dip NMO velocity (Vnmo), which could be approximately estimated by conventional techniques, we analyze the extended images obtained with distorted fields of the parameters η and δ. Differential semblance optimization (DSO) and stack-power estimates are employed to study the sensitivity of focusing to the anisotropy parameters. The results show that the signature of η is dip-dependent, whereas errors in δ cause defocusing only if that parameter is laterally varying. Hence, earlier results regarding the influence of η and δ on reflection moveout and migration velocity analysis remain generally valid in the extended image space for complex media. The dependence of RMO on errors in the anisotropy parameters provides essential insights for anisotropic wavefield tomography using extended images.Citation
Vladimir Li, Ilya Tsvankin, and Tariq Alkhalifah (2015) Analysis of RTM extended images for VTI media. SEG Technical Program Expanded Abstracts 2015: pp. 519-524. doi: 10.1190/segam2015-5930996.1Publisher
Society of Exploration GeophysicistsAdditional Links
http://library.seg.org/doi/10.1190/segam2015-5930996.1ae974a485f413a2113503eed53cd6c53
10.1190/segam2015-5930996.1