(a) Mono-channel seismic profile L1 (navigation track in Fig. 1b) showing the spatial arrangement of columnar shapes (pagodas). Pagodas are made up of chaotic sediments constituted by pumices and sands. The presence of a gas-saturated layer below the pagodas obliterates the continuity of the deeper stratigraphic layers. (b) Mono-channel seismic profile L2 (navigation track in Fig. 1b) with highlighted seafloor mounds, cut and deformations of the marine (MS) and pumice-sand sediments (PS). (c) Detail of the deformations in MS and PS are reported in (c,d). Assuming a velocity of 1580 m/s for the uppermost sediments, 100 ms represent about 80 m in the vertical scale.