Multibeam echosounder data collected on Southern Surveyor voyage SS2012_V03 using the Simrad EM300 multibeam echosounder to acquire high resolution seafloor bathymetry and backscatter information. This voyage took place in the Southern Ocean the 12th to the 25th July, 2012. Ping rate varied according to depth. Data are stored in Simrad *.all raw format at CMAR and Geoscience Australia (GA). There are 236 files totalling 2.26 Gb of raw data in this dataset. Additional information regarding this dataset is contained in the cruise report for this voyage and/or the data processing report (as available).