We present a phase shift datuming and migration algorithm for the data acquired on a nonflat surface. First of all, we formulate the exploding reflector modeling scheme for a nonflat recording surface. Then, the migration scheme is found as the conjugate operator of the modeling operator. In order to get the correct migration and datuming operators, the forward modeling must be physically reasonable because the conjugate operators are strongly dependent on the forward modeling operator. The artifacts caused by the non-unitary property of the operators can be reduced by a least-squares optimization technique.