Study on the one-step datuming method based on the straight-rays assumption

Based on the straight-rays approximation and the Snell law, a new datuming operator-Topographic Datuming Operator (TDO) is derived. The new redatuming operator derived here is based on straight-rays approximation above and below a chosen datum. It is directly applied to common-source gathers to downward continue the source and the receivers, simultaneously, from the rugged surface to the given datum level without resorting to common receiver gathers. As a result, the method is more efficient. In this paper, the theoretical foundation of the TDO is discussed in detail and the numerical tests are applied on the synthetic and real data.