YANG Fan, LAN Jiada, MENG Qingli, et al. Application of well-constrained travel time preserving tomography technology in Nanchuan area[J]. Petroleum Reservoir Evaluation and Development, 2021, (4): 514-520. DOI: 10.13809/j.cnki.cn32-1825/te.2021.04.006.
Application of well-constrained travel time preserving tomography technology in Nanchuan area
The southeastern Sichuan region has large elevation differences
complex surface conditions
large stratum dip
and complex conditions underground
so that the accurate imaging is difficult. In the support of shale gas exploration and development
there are problems of inconsistent well seismic wave group occurrence
false faults and well seismic prediction errors for the pre-processed data in this area. Aiming at these problems
the well-control anisotropic pre-stack depth migration method is proposed and applied to the above three-dimensional work area. By improving the accuracy of the velocity model
the seismic imaging accuracy of the complex fold area is improved
and it plays an important role in guiding the later well position
and improving the high-quality shale drilling rate. In this paper
the accuracy of the migration velocity model is finely characterized from two aspects: isotropy and anisotropy. Through the deep research and practice of high-precision grid tomography velocity modeling
travel(TPT)and TTI(transverse isotropic media with axial inclined symmetry)
the key technology series of seismic precision imaging in southeast Sichuan is gradually improved to enhance the well seismic yield consistency
reduce the well earthquake depth prediction error
eliminate the fault illusion of seismic profile
and provide important technical support for subsequent exploration and development of shale gas deployment.