oa Least Squares Wavepath Migration

We present the theory and some numerical examples for least squares wavepath migration (LSWM). This method migrates data by applying iterative conjugate gradients to the wavepath migration operator. Like least squares Kirchhoff migration, LSWM is designed for reducing migration artifacts, improving image resolution and energy focusing. Different from least squares Kirchhoff migration, LSWM is expected to be an inexpensive iterative algorithm because wavepath migration is computationally efficient. Numerical results with both synthetic and field data show that the LSWM image is noticeably better than the wavepath migration image resolution, artifacts attenuation, and interface continuity.