Our research vessel RV Polarstern is equipped with a PARASOUND DS2 sediment echosounder (ATLAS Hydrographic GmbH, Bremen). This echosounder generates two primary frequencies at ca. 18 and 22 kHz. The secondary frequency at 4 kHz that is produced through interference is used to image the upper up to 100 m of the sediment column in high lateral and vertical resolution. In addition, the 22 kHz signal can be used to image the water column.
Parasound profiles provide information about the nature and small-scale geometries of the seafloor and the uppermost sedimentary layers. We can detect if sediment was deposited in an undisturbed manner over several millennia. Wir also recognize slides and slumps, or ploughmarks that were generated by the keels of large icebergs. We also use Parasound data to identify spots suitable to take sediment cores.