HR: 1340h
AN: S23B-1387    [Abstracts]
TI: Integration of deformable layer tomography and shot gather modeling for pre-stack velocity and Q analysis
AU: * Cao, H
EM: hcao5@uh.edu
AF: University of Houston, Dept of Geosciences, 4800 Calhoun Street, Houston, TX 77204, United States
AU: Zhou, H
EM: h.zhou@ttu.edu
AF: Texas Tech University, Dept of Geosciences, Box 41053, 125 Science Building, Lubbock, TX 79409, United States
AB: Deformable layer tomography is a new layer based tomography method which can be used to integrate forward modeling and inverse approaches of pre-stack analyses of seismic velocity and Q. Traditionally forward modeling generates zero offset synthetic seismic traces based on logging data because such data provide the 1D profiles of reflector depth and rock property. In our work, forward modeling method was integrated with tomographic approach to generate pre-stack synthetic seismic wavelets along certain reflectors. Since the deformable layer tomography is based on layers instead of grids, it can provide 2D geometric information of each reflector and rock property across the reflector to facilitate a comparison with pre-stack seismic traces. We integrate the shot gather modeling with deformable layer tomography at two stages, the pre-inversion stage and post-inversion stage. The pre-inversion stage is to get initial velocity and Q depth models from shot gather modeling based on priori velocity and geology information. This procedure is interactive ¡§C one can select specific layer and then edit the nodes around the layer and rock property inside the layer through graphic user interface to achieve an approximated fit between the observed seismic traces and modeling result. The post- inversion stage is to edit the inverted velocity and Q model based on the difference between the observed seismic traces and the synthetic traces from the inverted depth model. This integration method has been applied to both synthetic and field tests. Those tests show that forward modeling can provide better initial model for the tomography algorithm to stabilize the inversion and shorten the convergent time. In addition, the inverted model can be further edited to get better match between the observed pre-stack seismic traces and the synthetic traces.
DE: 0545 Modeling (4255)
DE: 0900 EXPLORATION GEOPHYSICS
DE: 0935 Seismic methods (3025, 7294)
DE: 3260 Inverse theory
DE: 7270 Tomography (6982, 8180)
SC: Seismology [S]
MN: 2007 Fall Meeting