Borehole-driven 3D surface seismic data processing using DAS-VSP data

Abstract

Two walkaway DAS-VSP lines, zero offset VSP, offset VSP and two 2D 3C surface seismic lines data were acquired simultaneously using the borehole TF-02 in Southwest Oilfield of CNPC at Southwest China in order to perform the enhanced borehole-driven 3D surface seismic data processing and map the volcanic gas reservoir distribution. An armored optical cable with high temperature single mode fiber, dynamite and vibrator mixed sources were used to acquire the Walkaway DAS-VSP data. The walkaway DAS-VSP data were used to extract formation velocity, deconvolution operator, absorption, attenuation (Q value), anisotropy parameters (η, δ, ε) as well as enhanced the surface seismic data processing including velocity model calibration and modification, static correction, deconvolution, demultiple processing, high frequency restoration, anisotropic migration, and Q-compensation or Q-migration. In this project, anisotropic Q-PSDM was conducted with the anisotropy parameters (η, δ, ε) data volume and enhanced Q-field data volume obtained from the joint inversion of both the near surface 3D Q-field data volume from uphole data and the mid-deep layer Q-field data volume from all available VSP data in the 3D surface seismic survey area. The anisotropic Q-PSDM results show much sharper and focused faults and clearer subsurface structure.