Deabsorption prestack time migration from rugged topography

We developed a modified topography prestack time migration (PSTM) scheme that can improve the imaging resolution by applying effective Q to topography migration. The computation of the traveltime at each imaging location in the migration is based on the floating datum smoothed by rugged topography. Unlike the common quality factor Q the effective Q only determines the frequency-dependent amplitude and the traveltime at a single imaging location, which enables us to establish a Q model in an inhomogeneous medium. Hence, we can acquire the effective Q using a scanning technology according to the width of the frequency band and signal-to-noise ratio of the imaging gathers. The proposed migration method can be integrated into the conventional topography migration workflow. Synthetic and three-dimensional (3D) field datasets indicate that the proposed deabsorption PSTM from rugged topography is effective.