Processed Sub Bottom Profiler (SBP) data around Tristan da Cunha

Sub bottom profiler (SBP) aka sediment echosounder data. Sediment echosounder measurements were conducted continuously by means of Teledyne PARASOUND DS3 (P70) parametric sediment echosounder during both R/V MARIA S. MERIAN cruises, MSM20-2 (Jegen et al., 2015) and MSM24, until the shutdown of the system due to technical reasons on cruise MSM24. The system's beam width is 4.5° along-track and 5.0° across-track. The primary high frequency signal (PHF) with a frequency of about 18 kHz was recorded for water-column investigations while the secondary low frequency signal (SLF) with a frequency of 4 kHz is used to image the shallow sub-seafloor. This selection of four PARASOUND profiles were converted into SEG-Y data by using the PS32segy tool (Hanno Keil, University of Bremen, Germany). Afterwards, the ReflexW software57 (Sandmeier, 2012) was used to low-pass filter the data and to mute the water column.