This record describes multibeam echosounder data collected from the Marine National Facility (MNF) RV Investigator Voyage IN2020_V01, titled: “Development of William’s Ridge, Kerguelen Plateau: tectonics, hotspot magmatism, microcontinents, and Australia’s Extended Continental Shelf” between January 08 and March 06, 2020 departing from Henderson (WA) and returning back to Fremantle (WA). The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter at Rig Seismic Seamount, Williams Ridge, Broken Ridge and on associated transits. 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 2164 files totalling 174 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 from the Marine National Facility (MNF) RV Investigator Voyage IN2020_V01, titled: “Development of William’s Ridge, Kerguelen Plateau: tectonics, hotspot magmatism, microcontinents, and Australia’s Extended Continental Shelf” between January 08 and March 06, 2020 departing from Henderson (WA) and returning back to Fremantle (WA). The Kongsberg EM710 MKII multibeam echosounder was used to acquire seafloor bathymetry and backscatter information at Rig Seismic Seamount, Williams Ridge, Broken Ridge and on associated transits. 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 66 files totalling 5.6 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. 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_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 XBT data collected from the Marine National Facility (MNF) RV Investigator Voyage IN2020_V01, titled: “Development of William’s Ridge, Kerguelen Plateau: tectonics, hotspot magmatism, microcontinents, and Australia’s Extended Continental Shelf” between January 08 and March 06, 2020 departing from Henderson (WA) and returning back to Fremantle (WA). A total of 43 XBT casts were conducted over the duration of this voyage. Data are stored in netCDF files at CSIRO. 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_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 main area of survey was the Kermadec arc off of New Zealand. The Simrad EK60 split beam GPT for 18kHz and Simrad EK80 split beam WBTs for 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 1500 m during transits and to full ocean depth while at the New Zealand/Kermadec survey area. All frequencies were logged continuously for the extent of the voyage, except for a period of time between 26/03/2022 05:00 and 29/03/2022 11:05 UTC when all data recording was mandated to be suspended. The 70kHz was occasionally set to passive while in shallow water to limit interference with the EM710 multibeam. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 1773 files totalling 110 GB of raw data in this dataset. Transit data between Hobart and the New Zealand EEZ were post-processed for the Integrated Marine Observing System (IMOS) and posted to the Australian Ocean Data Network (AODN) Portal. 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 sub bottom profiler data collected from the Marine National Facility (MNF) RV Investigator Voyage IN2020_V01, titled: “Development of William’s Ridge, Kerguelen Plateau: tectonics, hotspot magmatism, microcontinents, and Australia’s Extended Continental Shelf” between January 08 and March 06, 2020 departing from Henderson (WA) and returning back to Fremantle (WA). The Kongsberg SBP120 (sub bottom profiler) was used to acquire data containing the specular reflections at different sediment interfaces below the seafloor. The SBP120 provides a 3° by 3° angular resolution. The echosounder's frequency sweep range is from 2.5 to 7 kHz. The SBP120 was logged continuously for the extent of the voyage. Data are stored in .raw (972 files 17.7 GB) raw and .seg (996 files 18.2 GB) segy formats at CSIRO. The segy format data had a real time processing stream applied, which applies gain, a gain correction, matched filter with replica shaping, an attribute calculation for instantaneous amplitude and time variable gain. 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 the Acoustic Doppler Current Profiler (ADCP) data collected from the Marine National Facility RV Investigator voyage IN2020_V01, titled: "Development of William’s Ridge, Kerguelen Plateau: tectonics,hotspot magmatism, microcontinents, and Australia’s Extended Continental Shelf." The voyage took place between January 10 and March 6, 2020, departing from Freemantle and returning to Freemantle. The primary scientific operations of the voyage were multibeam survey, seismic lines and dredging of the William’s and Broken Ridge features. ADCPs were turned off intermittently to avoid interference with multibeam during surveys. On Jan the 15th the OS75 was reporting excessively high temperatures. According to Uni of Hawaii, this is most likely due to water ingress into the transducer indicating potential failure. Temperatures eventually settled at full-scale (~97 deg C), which had a significant effect on calculated water velocities. Soundspeed was manually set to 1500 m/s (this is a setting sent to the deck box via UHDAS) for real-time processing, however special processing will be required for the period with bad temperatures and therefore bad soundspeed. Despite this, the OS75 worked well for the remainder of the voyage. Data was collected in two parts during the voyage at the following dates: First Part: 10 Jan. 2020 – 18 Jan. 2020 (8 days) Second Part: 12 Feb. 2020 – 06 Mar. 2020 (24 days) Note that there is no data from 19th Jan. to 11 Feb. Subsequently, two datasets have been created and processed separately for each part of the voyage. This dataset was processed (quality-controlled), and then archived by the CSIRO National Collections and Marine Infrastructure (NCMI) Information and Data Centre (IDC).

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 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 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 in the Coral Sea, within the EEZ of Australia, Papua New Guinea, Solomon Islands and New Caledonia. All frequencies were logged continuously for the extent of the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 766 files totalling 73.9 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 IN2018_V02, "SOTS: Southern Ocean Time Series automated moorings for climate and carbon cycle studies southwest of Tasmania" and "Subantarctic Biogeochemistry of Carbon and Iron, Southern Ocean Time Series site" which departed Hobart on the 03 March 2018 and returned to Hobart briefly on 12 March and finally concluded on the 21 March 2018. The Simrad EK60 split beam echosounders, 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data. The settings and monitoring were undertaken as part of a piggy back project, by Rudy Kloser, "Acoustic zooplankton and fish" . Data are stored in .raw, .bot and *.idx format at CSIRO. There are 3460 files totalling 65.6 GB of data in this dataset. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.