Fig. 4From: High-density surveys conducted to reveal active deformations of the upper forearc slope along the Ryukyu Trench, western Pacific, JapanStacked seismic profile of the upper forearc slope off central Okinawa-jima (see Fig. 2 for the track location). Typical profiles are shown across the upper forearc slope in the central Ryukyu island arc. The upper surface of the acoustic basement is shown to be deeper compared with that of the northern area (Fig. 3) and tilted southeastward. Seismic unit B, which is thick, attains 2.0 s (TWT) and is unconformably covered by seismic unit CBack to article page