This record describes multibeam echosounder data collected on RV Investigator voyage IN2018_V06, which departed Hobart on the 22-Nov-2018 and returned to Hobart on the 19-Dec-2018. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information between/around Huon, Tasman Fracture Marine Parks and the St Helens seamount, Tasmania. The EM122 provides a 1 degree by 1 degree angular resolution. The echosounder's nominal frequency is 12 kHz. Data are stored in *.all raw format for bathymetry and backscatter at CSIRO. There are 421 files totaling 27.0 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. Tide corrections [were/were not] applied to the processed data. Processed data had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter grids in geotiff format. Additional information regarding this dataset, including information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2019_V07, 'RAN Hydrographic and Maritime Heritage Surveys' which departed Hobart on the 11 April 2019 and returned to Hobart on the 23 April 2019. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information [and watercolumn backscatter] along the Tasmanian East Coast/Tasman Sea. The EM122 provides a 1 degree by 1 degree angular resolution. The echosounder's nominal frequency is 12 kHz. Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. There are 102 files totalling 3.37 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. Tide corrections were not applied to the processed data. Processed data had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter grids in geotiff format. Additional information regarding this dataset, including information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2019_V07, 'RAN Hydrographic and Maritime Heritage Surveys' which departed Hobart on the 11 April 2019 and returned to Hobart on the 23 April 2019. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information [and watercolumn backscatter] along the Tasmanian East coast and in the central to eastern region of Bass Strait. The EM710 MKII provides a 0.5° by 1° transmit and receive angular resolution respectively. The echosounder's nominal frequency range is from 40 to 100 kHz. Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. There are 337 files totalling 67 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. Tide corrections were applied to some of the processed data (i.e. AHO mapping area - files 0037 to 0112, and to other mapping sites - files 0188 to 0256). GPS tides (and reduction to AHD using AusGeoid 09) was applied to the BMR mapping areas (files 0257 to 0281, 0290 to 0293 & 0295 to 0300). Processed data has had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter grids in geotiff format. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2016_V02, which departed Hobart on the 14 March 2016 and returned to Hobart on the 16 April 2016. The Kongsberg EM710 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information around the shelf and slope south directly south of Tasmania. Ping rate varied according to depth. Data are stored in *.all raw format at CSIRO Oceans and Atmosphere. There are 41 files totaling 5.4 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Tide corrections were not applied to the processed data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2018_E01, Triaxus Sea Acceptance Testing & Calibrations Voyage, which departed Hobart on the 9th June 2018 and returned to Hobart on the 11th June 2018. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information for a small area off the southeast coast of Tasmania. The EM710 MKII provides a 0.5° by 1° transmit and receive angular resolution respectively. The echosounder's nominal frequency range is from 40 to 100 kHz. Data are stored in *.all raw format for bathymetry and backscatter at CSIRO. There are 7 files totalling 2.19 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. Tide corrections were not applied to the processed data. Processed data has had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter grids in geotiff format. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2019_T01 CAPSTAN which departed Hobart on the 29th April 2019 and returned to Fremantle on the 9th May 2019. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter around the south west coast of Western Australia and south coast of Tasmania. The EM710 MKII provides a 0.5° by 1° transmit and receive angular resolution respectively. The echosounder's nominal frequency range is from 40 to 100 kHz. Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. There are 68 files totaling 16 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. Tide corrections were applied to the processed data. Processed data has had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter grids in geotiff format. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2018_E02, titled 'MNF Trials and Calibrations' which departed Hobart on the 3rd of September 2018 and returned to Hobart on the 9th of September 2018. The Kongsberg EM710 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information around south eastern Tasmania. The EM710 provides a 0.5° by 1° transmit and receive angular resolution respectively. The echosounder's nominal frequency range is from 70 to 100 kHz. Data are stored in *.all raw format for bathymetry and backscatter at CSIRO. There are 97 files totalling 15.4 GB of raw data in this dataset. Multibeam bathymetry calibrations were performed on this trial. Tide corrections were not applied to the processed data. Processed data had outliers removed. Processed line data is not available as they were trials for calibration. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2018_E02, titled 'MNF Trials and Calibrations' which departed Hobart on the 3rd of September 2018 and returned to Hobart on the 9th of September 2018. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information [and watercolumn backscatter] around south eastern Tasmania. The EM122 provides a 1 degree by 1 degree angular resolution. The echosounder's nominal frequency is 12 kHz. Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. There are 68 files totalling 1.7 GB of raw data in this dataset. Multibeam bathymetry calibrations were performed on this trial. Tide corrections were not applied to the processed data. Processed data had outliers removed. Processed line data is not available as this was for calibration testing. Additional information regarding this dataset, including information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2016_V02, which departed Hobart on the 14 March 2016 and returned to Hobart on the 16 April 2016. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information around the SOTS site and eddy fronts at 52 deg south directly south of Tasmania. Ping rate varied according to depth. Data are stored in *.all raw format at CSIRO Oceans and Atmosphere. There are 652 files totaling 20.1 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Tide corrections were not applied to the processed data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2021_V02 (SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania), which departed Hobart on the 14th April 2021 and returned to Hobart on the 28th April 2021. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter during the voyage. The EM122 provides a 1 degree by 1 degree angular resolution. The echosounder's nominal frequency is 12 kHz. Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. There are 191 files totalling 11.4 GB of raw bathymetry & backscatter data, and 192 files totalling 14.7 GB of raw watercolumn data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. The data have been reduced to approximate Mean Sea Level (MSL) using the Earth Gravitation Model 2008 (EGM2008) 1 arc-minute grid. Tide corrections were not applied to the processed data. Processed data had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter grids in geotiff format. Additional information regarding this dataset, including information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.