This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2018_V01, Detecting Southern Ocean change from repeat hydrography, deep Argo and trace element biogeochemistry & CAPRICORN which departed Hobart on the 11 January 2018 and returned to Hobart on the 22 February 2018. The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 1500 m, between Hobart and 66°S. All frequencies were logged continuously for the extent of the voyage but no personnel were on board to monitor the acquisition. Data are stored in .raw, .bot and .idx format at CSIRO. There are 1041 .raw files totalling 94.8 GB of raw data in this dataset. Processing has been conducted on this data for the return transit from 66S to Hobart.

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 IN2019_V04, 'Hotspot dynamics in the Coral Sea: connections between the Australian plate and deep Earth', which departed Cairns on the 7th August 2019 and returned to Brisbane on the 3rd September 2019. The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter in the Coral Sea, within the EEZ of Australia, Papua New Guinea, Solomon Islands and New Caledonia. 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 977 files totalling 49.2 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_V04, 'Hotspot dynamics in the Coral Sea: connections between the Australian plate and deep Earth', which departed Cairns on the 7th August 2019 and returned to Brisbane on the 3rd September 2019. The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter on the continental shelf and continental slope to a depth of ~1000m, off Cairns and Brisbane. 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 27 files totalling 5.12 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 scientific split-beam echosounder data collected on the RV Investigator voyage IN2019_T02, titled: "Deep seascapes of the Great Barrier Reef: Uncovering submarine canyons and landslides." The voyage took place between October 4 and October 14, 2019 departing from Brisbane (QLD) and arriving in Darwin (NT). The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 1500 m, between Brisbane to Darwin transit. All frequencies were logged sporadically for the extent of the voyage. The frequencies were set to passive for the periods of the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 728 files totalling 36 GB of raw data in this dataset. The EK60, EM122 and SBP120 were synchronised using K-Sync as often as possible to minimise cross-system interference. No p/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 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 Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data, between Brisbane and Hobart. All frequencies were logged sporadically for the extent of the voyage. The frequencies were set to passive for the periods of the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 2,175 files totalling 41.7 GB of raw data in this dataset. No processing has been conducted on this data. Data spans 5/04/2018 20:00 until 06/04/2018 06:00 UTC. 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 IN2017_V02, 'SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania' which departed Hobart on the 17 March 2017 and returned to Hobart on the 28 March 2017. The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 0-1500 m, around Southern Ocean. All frequencies were logged continuously for the extent of the voyage. The frequencies were set to passive for the periods during the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are [XXXX] files totalling [XXXX] 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 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 Simrad EK60 split beam echosounders 12, 18, 38, 70 120, 200 and 333 kHz frequencies were used to acquire acoustic backscatter data to a range of 1500 m, around the Great Australian Bight. All frequencies except for the 12 kHz were logged continuously for the extent of the voyage. The 12 kHz was logged for a portion of the voyage, but was also set to passive mode periodically. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 998 files totaling 83.7 GB of raw data in this dataset. Some processing has been conducted on this data, which will be available through IMOS. 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 IN2017_V03, 'Sampling the abyss: latitudinal biodiversity patterns along the base of Australia’s eastern continental margin' which departed Bell Bay on the 15 May 2017 and returned to Brisbane on the 16 June 2017. The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data when possible. All frequencies were logged mainly when transitting between sites as all ship acoustics were turned off when listening for beacon signals on most operations. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 45.5 GB of raw data in this dataset. Amy Nau, will be processing 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 IN2018_V06, which departed Hobart on the 22-Nov-2018 and returned to Hobart on the 19-Dec-2018. The Simrad EK60 split beam echosounders [12], 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of [range] m, Huon, Tasman Fracture Marine Parks and the St Helens seamount, Tasmania.. All frequencies were logged continuously for the extent of the voyage The frequencies were] set to passive for the periods when tracking towed bodies using USBL. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 4690 files totalling 90 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.