This record describes multibeam echosounder data collected on RV Investigator research charter, IN2015_C01, 'GAB deep water geological and benthic ecology program' which departed Hobart on the 25 October and returned to Port Lincoln on the 28 November. A short sea trial voyage (October 22 - 25, Hobart - Hobart) was undertaken prior to the charter. Data for those days is also included in this data set. The Kongsberg EM710 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter. 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 and .wcd format for watercolumn backscatter at CSIRO. There are 65 files totalling 4.93 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format is 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 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 scientific split-beam echosounder data collected on RV Investigator research charter, IN2015_C01, 'GAB deep water geological and benthic ecology program' which departed Hobart on the 25 October and returned to Port Lincoln on the 28 November. A short sea trial voyage (October 22 - 25, Hobart - Hobart) was undertaken prior to the charter. Data for those days is also included in this data set. The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data during the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 6795 files totalling 102 GB of raw data in this dataset. No processing has been conducted on this 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 IN2015_c02, Great Australian Bight Research Program: GAB deep-water pelagic and benthic ecosystem study which departed Port Lincoln on the 30 November 2015 and returned to Fremantle on the 22 December 2015. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter and watercolumn backscatter information around the Great Australian Bight. 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 287 .all files and 13 .wcd files totalling 11.6 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 IN2017_C01, 'GAB deep water geological and benthic ecology program' which departed Hobart on the 11 April 2017 and returned to Hobart on the 28 April 2017. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter around the GAB. 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 645 files totalling 20.5 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 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 IN2017_C02, ['Hogan Group Hydrographic Survey – Bass Strait'] which departed Hobart on the 4th May 2017 and came alongside Bell Bay following completion of the survey on the 14th May 2017. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information [and watercolumn backscatter] around 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 465 files totalling 156 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 using AusTides 2017. Processed data has had outliers removed. Processed line data are not available in *.gsf and ascii format, but can be requested. 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 IN2017_C02, ['Hogan Group Hydrographic Survey – Bass Strait'] which departed Hobart on the 4th May 2017 and came alongside Bell Bay following completion of the survey on the 14th May 2017. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information [and watercolumn backscatter] around Bass Strait. 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 236 files totalling 9.5 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 had outliers removed. Processed line data are not available in *.gsf and ascii format, however can be requested if required. 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 IN2018_T01, titled: "Physical and biogeochemical gradients in the East Australian Current." The voyage took place from Hobart (TAS) to Brisbane (QLD) between April 5 and April 14, 2018. The Kongsberg EM710 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information between Brisbane coastline towards Hobart. 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 36 files totalling 5.76 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. Please note that data quality may be affected as the unit was left unattended while testing took place on the underway SVP. There are small refraction errors present in some of the shallow water data as a result. 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 the Marine National Facility RV Investigator voyage IN2015_V01. This is the first research voyage for the RV Investigator departing Hobart on the 21 March and returning to Hobart on the 30 March, 2015. The Kongsberg EM710 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information when in water less than 1000 m. Ping rate varied according to depth. Data are stored in *.all raw format at CSIRO Oceans and Atmosphere. There are 19 files totaling 3.48 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 available on request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2018_T01, titled: "Physical and biogeochemical gradients in the East Australian Current." The voyage took place from Hobart (TAS) to Brisbane (QLD) between April 5 and April 14, 2018. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information between Brisbane coastline towards Hobart. 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 184 files totalling 6.08 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 the RV Investigator voyage IN2023_V04, International nutrient inter-comparison Voyage (INIV) which departed Hobart on the 05/06/23 and returned to Hobart on the 18/06/23. The Kongsberg EM710 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter in the Southern Ocean Southwest of Hobart. 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 and .wcd format for watercolumn backscatter at CSIRO. There are 110 files totalling 90.3 GB of raw data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format is 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 further information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.