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 scientific split-beam echosounder data collected on the 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 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 1500 m, between Sydney and Brisbane, with primary mapping focused on Richmond and Solitary Canyons. If the bottom was deeper than 1500 m during the camera operations the logging range was extended to capture the full water column. All frequencies were logged sporadically for the extent of the voyage as to not interfere with the ADCP which took priority over the EK60/EK80 to fulfil the voyage objectives. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 312 files totalling 28.4 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 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 scientific split-beam echosounder data collected on the RV Investigator voyage IN2023_V03, SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania which departed Hobart on May 12, 2023 and returned to Hobart on the May 25, 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 1500 m, between Hobart, the SOTS location and while on site. All frequencies were logged continuously for the extent of the voyage. There was a dedicated acoustic survey over the Patience Seamount while transiting to SOTS and also some opportunistic noise data collection to compare EK60 and EK80 noise levels. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 1130 files totalling 53 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 scientific split-beam echosounder data collected on the RV Investigator voyage IN2023_V06, titled: "Understanding Eddy Interactions and Their Impacts In the East Australian Current System." The voyage took place between October 9 and November 2, 2023, departing from Sydney (NSW) and returning to Sydney. 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 1500m, around NSW/VIC coastal areas. All frequencies were logged continuously for the extent of the voyage. The 70kHz & 120kHz frequencies were set to passive for the periods of shallow mapping areas of the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 394 files totalling 35.6 GB of raw data in this dataset. No post 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 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 scientific split-beam echosounder data collected on the RV Investigator voyage IN2024_V03, titled "Untangling the causes of change over 25 years in the southeast marine ecosystem (SEA-MES Voyage 2)." The voyage took place between May 01, 2024 and May 31, 2024 (AEST), departing from Hobart and returning to Sydney. 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 1500 m, between the shelf areas of eastern Australia from Hobart, TAS to Sydney, NSW. All frequencies were logged continuously for the extent of the voyage. The frequencies 70kHz & 120kHz were set to passive for small periods of mapping during the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 688 files totalling 64.3 GB of raw data in this dataset. No post 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 scientific split-beam echosounder data collected on the RV Investigator voyage IN2022_V06, titled "Integrated Marine Observing System: monitoring of East Australian Current property transports at 27 degrees South." The voyage took place between July 14 and July 30, 2022 (AEST), departing from Brisbane and returning to Brisbane. 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 1,500 m, around Brisbane 27 degrees South. All frequencies were logged continuously for the extent of the voyage, except when asked to switch off for mooring activities. Occasionally, the 70kHz & 120kHz frequencies were set to passive for the periods of shallow mapping with EM710, and ADCP interference requests from the chief scientist, but all other frequencies wer set to active during the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 877 files totalling 40 GB of raw data in this dataset. No post 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_V05 "The Tsunamigenic Submarine Landslides and Deep-Marine Canyons of Australia’s Tasman Sea Margin: Causes and Consequences" which departed Hobart on 28th Mar 2022 and arrived at Brisbane on 3rd Jul 2022. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter along the East coast of Australia. 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 846 files totalling 524 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. EGM2008 height reduction was applied to the processed data. Processed data has had outliers removed. Processed line data are available in *.gsf and ascii 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 the RV Investigator voyage IN2025_V02, ' SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania ' which departed Hobart on the 26th March and returned to Hobart on the 14th April 2025. The Simrad EK80 split beam echosounders for 18, 38, 70 120, 200 were used to acquire acoustic backscatter data to a range of 1500 m. All of these frequencies were logged continuously for the extent of the voyage with the exception of periods of mooring triangulations. The 333 kHz was set to passive for the duration of the voyage due to a known issue with the transducer. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 807 files totalling 76 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.