Seismic illumination: Two-dimensional forward numerical seismic modeling and migration study to evaluate imaging complex structure

2D forward numerical seismic modeling of a complex geology structure was used to optimize the acquisition parameters, to evaluate processing techniques, and to aid in the seismic interpretation. Synthetic seismic data were acquired using a numerical model of a fault-fold structure encountered in northeastern British Columbia. These gathers are used to investigate which migration algorithms would produce the best images in such complex environments. Pre-stack depth migration from the topography with the known velocity model was found to give the optimum migrated image. Acoustic and elastic numerical modeling techniques were used to simulate waves propagating in the complex medium.;A near vertical structure that was difficult to image was chosen for a comprehensive analysis. This seismic structural imaging investigated the target locations in the Husky line, Muskwa region. The line is severely affected by the harsh topography, velocity variations and complex geometry that cause severe ray bending. Prestack time migration (PreSTM) cannot handle the lateral velocity variations and the severe ray bending introduced by such complex geometry. It caused deterioration of the image that poses problems for interpretation. To alleviate this problem, I used an isotropic Kirchhoff prestack depth migration (PreSDM) (from TESSERAL modeling and migration software) incorporating the exact velocity model was used. This was subsequently followed by imaging with phase shift and split-step migrations and another Kirchhoff PreSDM from ProMax 2D software. Comparison of the resulting images from the four migration algorithms shows a variation in the imaging quality.