This record describes magnetometer 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 instrument is a Marine Magnetics SeaSPY2 magnetometer and was deployed continuosly for the voyage except during 2D Multi-channel Seismic acquisition and Rock Dredging operations. Data are stored in .CSV and .MMS data files at CSIRO. 40.7 GB of raw data was acquired in this dataset. No processing has been conducted on this data. The magnetometer was towed 300m astern of the ship and a layback value of 361m was applied to the magnetometer data. This was the total distance behind the ship's positioning reference point. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes magnetometer data collected on RV Investigator voyage IN2020_V06, titled "Probing the Australian-Pacific Plate Boundary: Macquarie Ridge in 3-D." The voyage took place between October 8 and November 3, 2020 departing from Hobart (TAS) and arriving in Hobart (TAS). The SeaSPY2 magnetometer uses an omnidirectional Overhauser sensor that requires no realignment or recalibration and has no heading error. The instrument has an absolute accuracy of 0.1 nT, sensor sensitivity of 0.01 nT and resolution of 0.001 nT. Data are stored in .CSV and .MMS data files at CSIRO. 219 MB of raw data was acquired in this dataset. No processing has been conducted on this data. The magnetometer was towed 300 m astern of the ship and a layback value of 361 m was applied to the magnetometer data. This was the total distance behind the ship's positioning reference point. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes magnetometer data collected on RV Investigator voyage IN2023_V01, titled "Antarctic Bottom Water Production in the past: Records from marine sediments, Cape Darnley, East Antarctica". The voyage took place between 25th January, 2023 and 2nd March, 2023 departing from Henderson's (WA) and arriving in Hobart (TAS). The SeaSPY2 magnetometer uses an omnidirectional Overhauser sensor that requires no realignment or recalibration and has no heading error. The instrument has an absolute accuracy of 0.1 nT, sensor sensitivity of 0.01 nT and resolution of 0.001 nT. Data are stored in .CSV and .MMS data files at CSIRO. 15 final files for 150 MB were exported as .csv files in this dataset. No processing has been conducted on this data. A total of 3,909 track kilometre's of magnetometer data was collected. The magnetometer was towed ~300 m astern of the ship and a layback value of 361 was applied to the magnetometer data. This was the total distance behind the ship's positioning reference point. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes magnetometer 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 instrument is a Marine Magnetics SeaSPY2 magnetometer and was deployed while transiting during the voyage in the Coral Sea, within the EEZ of Australia, Papua New Guinea, Solomon Islands and New Caledonia. Data are stored in .CSV and .MMS data files at CSIRO. 872 MB of raw data was acquired in this dataset. No processing has been conducted on this data. The SeaSPY2 magnetometer uses an omnidirectional Overhauser sensor that requires no realignment or recalibration and has no heading error. The instrument has an absolute accuracy of 0.1 nT, sensor sensitivity of 0.01 nT and resolution of 0.001 nT.” The magnetometer was towed 300m astern of the ship and a layback value of 361m was applied to the magnetometer data. This was the total distance behind the ship's positioning reference point. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes magnetometer data collected on 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 May 25, 2023. The SeaSPY2 magnetometer uses an omnidirectional Overhauser sensor that requires no realignment or recalibration and has no heading error. The instrument has an absolute accuracy of 0.1 nT, sensor sensitivity of 0.01 nT and resolution of 0.001 nT. Data are stored in .CSV and .MMS data files at CSIRO. 34.0MB of raw data was acquired in this dataset. No processing has been conducted on this data. The magnetometer was towed 300 m astern of the ship and a layback value of 361 m was applied to the magnetometer data. This was the total distance behind the ship's positioning reference point. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes magnetometer data collected on RV Investigator voyage IN2022_V08, titled "Biodiversity Assessment of Australia’s Indian Ocean Territories", which departed Darwin on September 30 and returned to Fremantle on November 3, 2022. This was a continuation of voyage IN2021_v04. The SeaSPY2 magnetometer uses an omnidirectional Overhauser sensor that requires no realignment or recalibration and has no heading error. The instrument has an absolute accuracy of 0.1 nT, sensor sensitivity of 0.01 nT and resolution of 0.001 nT. Data are stored in .CSV and .MMS data files at CSIRO. 92 MB of raw data was acquired in this dataset. No processing has been conducted on this data. The magnetometer was towed ~300 m astern of the ship and a layback value of 361 was applied to the magnetometer data. This was the total distance behind the ship's positioning reference point. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes magnetometer data collected on RV Investigator voyage IN2024_T01, 'Transit Voyage: Fremantle to Hobart.' The primary objective of the voyage was the safe and timely transit of RV Investigator from Fremantle to Hobart in preparation for the following research voyage. During the transit various research projects were conducted, along with outreach, familiarisation and training activities. The voyage departed Fremantle on the 09 March and returned to Hobart on the 20 March. The SeaSPY2 magnetometer uses an omnidirectional Overhauser sensor that requires no realignment or recalibration and has no heading error. The instrument has an absolute accuracy of 0.1 nT, sensor sensitivity of 0.01 nT and resolution of 0.001 nT. Data are stored in .CSV and .MMS data files at CSIRO. 132 MB of raw data was acquired in this dataset. No processing has been conducted on this data. The magnetometer was towed 300 m astern of the ship and a layback value of 376 m was applied to the magnetometer data. This was the total distance behind the ship's positioning reference point. Additional information regarding this dataset is contained in the GSM data acquisition and processing report.

This record describes the Heat Flow Probe data collected on the RV Investigator Charter Voyage IN2015_C01, titled "Great Australian Bight (GAB) Deep Water Geological and Benthic Ecology Program." This charter voyage took place from Hobart to Port Lincoln between the 22nd of October and the 28th of November 2015. The Heat Flow Probe is a sediment penetrating device to measure depth-dependent sediment temperatures and sediment thermal parameters as thermal conductivity to determine marine geothermal heat flow. Calibration of analog/digital channels was done in laboratory; find calibration coefficients in the document 'CTM1000_Konstantenprotokoll_30°C.pdf.' Temperature NTC sensors were calibrated in deep sea (HF06, TRPBE_056), resulting T_Offsets are in file 'TOffset_HF06-ZB100546.dat;' for calibration details contact FIELAX GmbH. The raw data was processed during the voyage and stored in a custom raw (TOB) format and processed CSV format (refer to readme-HF-fomats.txt). On this particular voyage, the heat flow probe successfully performed the deepest measurements (in the Bight Basin, Offshore South Australia) to 5,432 m water depth, reaching a new record for FIELAX and our equipment. Access to the datasets is managed by CSIRO Energy (Clayton) as an output of the GAB Marine Program, and any publication requires prior approval.

This record describes the geological sample data collected on the RV Investigator Charter Voyage IN2015_C01, titled "Great Australian Bight (GAB) Deep Water Geological and Benthic Ecology Program." This charter voyage took place from Hobart to Port Lincoln between the 22nd of October and the 28th of November, 2015. The voyage, undertaken over 34 days, was a great success with 37 researchers from seven research organisations and the vessel crew undertaking 128 operations over 17 target areas in water depths ranging from 700 m to 5,437 m. The voyage deployed a diverse and large collection of instrumentation fully utilising the Investigator capabilities. This involved the deployment of some of the equipment types significantly deeper than previous deployments either in Australia or worldwide. The data and samples collected significantly augment the sparse data and sample collections within the deep water GAB to date. Over 1.36 tons of rock and 15.2 m of sediment core were collected. This record contains data from the analysis of geological samples collected. Documents and files of geological sample analyses can be accessed and downloaded via the Distribution links below.

This record describes Hydrology (HYD) data collected from the Marine National Facility (MNF) RV Investigator voyage in2016_v02, titled "IMOS Southern Ocean Time Series Automated Moorings for Climate and Carbon Cycle Studies Southwest of Tasmania." This voyage took place between the 14th of March, 2016 and the 16th of April, 2016, departing from Hobart (TAS) and returning to Hobart. Hydrology samples were collected from Niskin bottles sampled at various depths during a Conductivity-Temperature-Depth (CTD) deployment. Parameters analysed were salinity, dissolved oxygen, phosphate, silicate, nitrate plus nitrite and ammonium. Samples were also collected every 2 hours for nutrient analysis from the underway system which collects water from 7 m depth and is not filtered. This dataset has been archived at the CSIRO O&A Information and Data Centre (IDC) in Hobart. Additional information regarding this dataset is contained in the Voyage Report and Data Processing Report.