Erroneous designation of file names: dates of file names are shifted backwards by one day.Latitude/Longitude extracted from DSHIP.Data acquisition was performed using a multibeam sonar system Simrad EM-122 from Kongsberg. Raw data are delivered within Simrad current multibeam vendor format. SIMRAD raw data can be processed i.e. with the software packages CARIS HIPS/SIPS, Caraibes, QPS Qimera or with the open source software package MB-System (http://www.ldeo.columbia.edu/res/pi/MB-System/).These data should not be used for navigational purposes.