PSPI depth-migration of data acquired over a channel physical model

Joe Wong

We conducted a physically-modeled marine seismic survey over a simple 2D layered earth structure with an embedded channel. The recorded acoustic data are intended for testing fast depth-migration and FWI algorithms. We investigate the exploding reflector approximation as a faster alternative to standard finite-difference modeling of forward wave propagation. We also studied PSPI depth-migration as a faster alternative to finite difference backward propagation of data residuals. All numerical methods for inverting field seismic data to velocity structure and reflectivity require an accurate velocity model. Although in a physical model, the true geometric structure and velocities are known a priori, in a real world situation neither is fully known. They need to be derived from the recorded field data using velocity analysis. We did this for the data from the physically-modeled survey. The resulting derived interval velocity field is an approximation to the true velocity structure. We compared results based on the true velocity field and the derived velocity model. We evaluated the effectiveness of using exploding reflector and PSPI depth-migration calculations to analyze physically-modeled seismic data.