Efficient elastic reverse time migration for the decomposed P wavefield using stress tensor in the time domain
Summary To obtain accurately migrated image in elastic media, wavefield decomposition is needed. In particular, conventional decomposed P wavefield is obtained by using divergence operator. Because stress tensor can be formulated by space differentiated displacement, in this paper, it was used to decompose P wavefield. And absolute value function was applied to decomposed P wavefield with stress tensor for acquisition of identical polarity of upand down going wavefield. Using these approaches, we developed two types of migration algorithms. To examine feasibility of our migration algorithms, we carried out the numerical tests. Through these results, we can obtain reasonable migrated images by using our imaging conditions.