Sediment echosounder data was recorded during R/V SONNE cruise SO219A (Yokohama-Yokohama) between 08.03.2012 and 06.04.2012 in the Northwestern Pacific (Japan Trench) and was divided into two Legs. The main research goal of the cruise was to investigate the sedimentary fingerprint left by the 2011 Tohoku-Oki earthquake. Therefore, the Remotely Operated Vehicle (ROV) QUEST (MARUM) was used to explore the fault zones and normal fault systems. Additionally, slumps and seeps, which might be related to the fault systems and therefore to the earth quake, were further explored using the ship-mounded hydroacoustic equipment (Multibeam and ParaSound) (https://media.suub.uni-bremen.de/handle/elib/3017). During the R/V SONNE cruise SO219A/1 the hull-mounted ATLAS PARASOUND P70 system was used during the entire hydroacoustic surveying. It is utilizing the parametric effect of the non-linear relation of pressure and density during sonar propagation. Data acquisition was performed using real-time values of surface sound velocity and a static sound velocity profile of 1500 m/s. Using the software ATLAS PARASTORE, data was displayed and stored as raw .asd files (and its zipped versions .asd.acf with aux-file .asd.acf.idx) and can further be processed and converted into .ps3 / *.sgy file format.

Responsible person during this cruise / PI: Christian dos Santos Ferreira (cferreira@marum.de)A special thanks goes to the following watchkeepers during SO219A: Sato, Takeshi, Kanamatsu, Toshiya