Fig. 9

Horizontal array displacements for the actual data at site G19. Horizontal array displacements estimated by the conventional array positioning method with fixed vertical array displacements are shown as black inverse triangles in Fig. 7a, b and are re-shown as colored dots in a and b for the east–west and the north–south components, respectively. Horizontal array displacements estimated by the EKF-based array positioning method assuming a laterally stratified SSS, shown as blue squares in Fig. 7a, b, and re-shown as colored dots in c and d for the east–west and the north–south components, respectively. The colors represent the number of the responsive seafloor transponders at the corresponding acoustic ping