In the current rip region, the sound propagation from the TuWE side toward the OyCWm side are compared for FlatB, IncB, and ActB, and is examined. When SD in FlatB is shallow, sound field is formed with CZ and BB propagation. When the source depth becomes deep, SC propagation is generated in addition to CZ and BB propagation. The formation of CZ propagation is obstructed by the bottoms, and BB propagation is controlled by the inclination of bottoms. When SD becomes deep, SC propagation is formed, and TL becomes small. The bottom obstructs the formation of CZ propagation, and the inclination of the bottom contributes to the change in the reflection direction.