Parametric seismic profiles were obtained with a hull-mounted TOPAS PS 018 high-resolution parametric sounder designed for sub-bottom profiling with very high spatial resolution in water depths from less than 20 meters to full ocean depth. The +80% relative bandwidth, low frequency signal is generated in the water column by non-linear interaction between two high frequency signals (centered symmetrically around 18 kHz). The seismic profiles obtained were recorded working in high-penetration mode, by transmission of a Chirp wave (LFM), trying at all times not to interfere with the EM122 multibeam echosounder signal. Normal transmission frequencies vary from 2.0 kHz for the initial and 5 kHz for the final, with a pulse length of 10 ms, and transmitted at a 1,500 ms internal mode trigger interval. The record length was 400 ms at a sampling rate of 16.0 Hz. The deconvolution and initial 2 kHz filtering (HP filter) of the signal have always been applied in this Chirp mode. The TVG ramps normally used during the acquisition have been 0.78 d/ms between the bottom and 5.4 ms depth, 0.77 d/ms between 5.4 and 25.9 ms, and 0.14 d/ms after 35.6 ms.