This record describes multibeam echosounder data collected on RV Investigator voyage IN2023_V02, titled "Gigantic submarine landslide offshore western Tasmania: risk mitigation for shelf derived tsunami in Australia", which departed Hobart on March 24 and returned to Hobart on April 30, 2023. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter during the voyage to the SW of Tasmania (Hobart to 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 and .wcd format for watercolumn backscatter at CSIRO. There are 458 files totalling 70.5 GB of raw bathymetry/backscatter data and 458 (*.wcd) files totaling 528 GB of 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. GPS tide was computed using the EGM2008 model and applied to the processed data for most lines. In some cases of bad navigation due to runoff issues with the POSMV, data were reduced using tides instead of GPS heighting and complemented by the application of delayed heave. These lines are noted in the multibeam processing log (in2023_v02_MBES_processing_log.xlsx). 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 IN2023_V02, titled "Gigantic submarine landslide offshore western Tasmania: risk mitigation for shelf derived tsunami in Australia", which departed Hobart on March 24 and returned to Hobart on April 30, 2023. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter during the voyage to the SW of Tasmania (Hobart to 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 and .wcd format for watercolumn backscatter at CSIRO. There are 938 files totalling 39.5 GB of raw bathymetry/backscatter data and 937 (.wcd) files totaling 56.7 GB of 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. GPS tide was computed using the EGM2008 model and applied to the processed data. In some cases of bad navigation due to runoff issues with the POSMV, the Seapath navigation (Nav source 3) was applied instead. These lines are noted in the multibeam processing log (in2023_v02_MBES_processing_log.xlsx). 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 IN2024_V04, 'Linking East Australian Current dynamics and submarine canyon geomorphology to marine ecosystem hotspots' which departed Sydney on the Friday 7th and returned to Brisbane on the on the Wednesday 3rd July. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter between Sydney and Brisbane, with primary mapping focused on Richmond and Solitary Canyons. 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 250 files totalling 37.8 GB of raw data and 250 files totalling 284 GB of 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. GPS tide was computed using the EGM2008 model and applied to the processed data. Processed data has had outliers removed. Processed line data are available in .gsf and ascii format, and processed bathymetry 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 IN2024_V04, 'Linking East Australian Current dynamics and submarine canyon geomorphology to marine ecosystem hotspots' which departed Sydney on the Friday 7th June and returned to Brisbane on the Wednesday 3rd July. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter between Sydney and Brisbane, with primary mapping focused on Richmond and Solitary Canyons. 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 633 files totalling 32 GB of raw data and 633 files totalling 40.3 GB of 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. GPS tide was computed using the EGM2008 model and applied to the processed data. Processed data has had outliers removed. Processed line data are available in .gsf and ascii format, and processed bathymetry 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 IN2015_V03, which departed Brisbane on the 3rd June 2015 and arrived Sydney on 18th June 2015. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information in the Tasman Sea. Ping rate varied according to depth. Data are stored in *.all raw format at CSIRO Oceans and Atmosphere. There are 368 files totalling 18.2 GB of raw data in this dataset. 31 sound velocity profiles were applied to this data during data acquisition. Tide corrections were not applied to the processed data. Processed data are available in XYZ and GSF format. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2022_V05 "The Tsunamigenic Submarine Landslides and Deep-Marine Canyons of Australia’s Tasman Sea Margin: Causes and Consequences" which departed Hobart on the 28th Mat 2022 and returned to Brisbane on the 3rd of July 2022. The Simrad EK60 split beam echosounders for18kHz and Simrad EK80 split beam echosounders for 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 250m and 1500m along the East coast of TAS, NSW and QLD. All frequencies were logged for the extent of the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 1378 files totalling 134 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_V03, which departed Brisbane on the 3rd June 2015 and arrived Sydney on 18th June 2015. The Kongsberg EM710 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information in Tasman Sea. Ping rate varied according to depth. Data are stored in *.all raw format at CSIRO Oceans and Atmosphere. There are 168 files totaling 18.4 GB of raw data in this dataset. 31 sound velocity profiles were applied to this data during data acquisition. Tide corrections were not applied to the processed data. Processed data are available in XYZ and GSF format. 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 IN2015_V02, which departed Sydney on 15 May 2015 and arrived in Brisbane on 26 May 2015. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information off Fraser Island out to the abyssal plain, surveying for suitable mooring locations. Ping rate varied according to depth. Data are stored in *.all raw format at CSIRO Oceans and Atmosphere. There are 167 files totalling 4.66 GB of raw data in this dataset. Processed data are available in XYZ and GSF format. 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 scientific split-beam echosounder data collected on the RV Investigator voyage IN2023_V02, titled "Gigantic submarine landslide offshore western Tasmania: risk mitigation for shelf derived tsunami in Australia", which departed Hobart on March 24 and returned to Hobart on April 30, 2023. The Simrad EK60 split beam echosounders for 18kHz and Simrad EK80 split beam echosounders for 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 250 m (shallow water) or 1500 m (deep water) during the voyage to the SW of Tasmania (Hobart to Hobart). All frequencies were logged continuously for the extent of the voyage, except on occasions when undertaking bathymetry mapping in shallow water on the shelf when the 38, 70 and 120 kHz frequencies (together or separately) were set to passive for to avoid interference with the EM710 echo sounder. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 1500 files totalling 138 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 IN2022_V02, titled "Sedimentation at its extreme: how powerful are submarine caldera-forming eruptions (Kermadec arc)?" The voyage took place between March 15, 2022 and April 19, 2022 (AEST), departing from Hobart and returning to Hobart. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter in shallow water (<500m) on the shelf of Tasmania and a small portion of the New Zealand continental shelf. 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. During IN2022_V02 the frequency range was set from 70 to 100kHz. Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. There are 37 .all files totaling 8.15 GB of raw bathymetry/backscatter data and 31 .wcd files totaling 48.7GB of 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. GPS tide was computed using the EGM2008 model and 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.