This record describes deeper multibeam data collected on RV Tangaroa voyage TAN2021_V01 (NIWA TAN2113), which was carried out on a contract to the CSIRO MNF from 9th November to 4th December 2021. The voyage had two objectives, which were to recover 27 Ocean Bottom Seismometers which had been deployed around Macquarie Island on IN2020_v06, and complete multibeam and sub bottom profiler mapping along the crest of the Macquarie Ridge and collect new multibeam data during transits. The Kongsberg Maritime EM302 was used to obtain swath bathymetry, backscatter, and water column data in deeper water (down to 7000 m), using Kongsberg Seafloor Information System (SIS) version 4.3.2 acquisition system. The EM302 is a 1 TX by 2 RX system, with 288 beams (or 576 beams in dual swath mode), yielding 432 soundings (or 864 soundings in Dual Swath mode ). Water column data, which show the received amplitude of the entire water column for each beam, were recorded simultaneoulsy with the multibeam echosounder data. Data are stored in *.all raw format for bathymetry and backscatter and *.wcd format for watercolumn backscatter at CSIRO. There are 201 files totalling 25.2 GB of raw data in this dataset. There are 200 files totalling 43.8 GB of water colomn data. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. Raw data (*.all files) were processed using QPS Qimera v2.4.2 for bathymetry and QPS Geocoder Toolbox (FMGT) v7.10.0 for acoustic seafloor backscatter. *.gpd files were generated by Qimera for each *.all file after editing. The quality of the bathymetry data was examined, and surfaces of varying resolution generated for each survey area. The data were cleaned in both 2D and 3D manually. Where appropriate a medium spline filter was used. Gridded bathymetric surfaces were projected in WGS84 / UTM zone 57S (EPSG:32757) coordinate reference system at varying resolutions. Bathymetry datasets were collated, and maps produced in ArcGIS Pro v2.8.3. Water column data files (.wcd) consisting of 165 files, 31.1 GB, were not processed onboard. Additional information regarding this dataset is contained in the "NIWA Voyage Report 2022007WN.pdf". The report is available from Geophysical Survey and Mapping (GSM) group at CSIRO upon request.

This record describes shallow multibeam data collected on RV Tangaroa voyage TAN2021_V01 (NIWA TAN2113), which was carried out on a contract to the CSIRO MNF from 9th November to 4th December 2021. The voyage had two objectives, which were to recover 27 Ocean Bottom Seismometers which had been deployed around Macquarie Island on IN2020_v06, and complete multibeam and sub bottom profiler mapping along the crest of the Macquarie Ridge and collect new multibeam data during transits. The Kongsberg Maritime EM2040 was used to obtain swath bathymetry, backscatter, and water column data in shallower water (20 - 300 m), using Kongsberg Seafloor Information System (SIS) version 4.3.2 acquisition system. The EM2040 is a single RX system, with 256 beams (or 576 beams in dual swath mode), yielding 400 soundings (or 800 soundings in High Density mode). Water column data, which show the received amplitude of the entire water column for each beam, were recorded simultaneoulsy with the multibeam echosounder data. Data are stored in *.all raw format for bathymetry and backscatter and *.wcd format for watercolumn backscatter at CSIRO. There are 129 files totalling 11.6 GB of raw data in this dataset. There are 129 files totalling 152 GB of water column data. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. Raw data (*.all files) were processed using QPS Qimera v2.4.2 for bathymetry and QPS Geocoder Toolbox (FMGT) v7.10.0 for acoustic seafloor backscatter. *.gpd files were generated by Qimera for each *.all file after editing. The quality of the bathymetry data was examined, and surfaces of varying resolution generated for each survey area. The data were cleaned in both 2D and 3D manually. Where appropriate a medium spline filter was used. Gridded bathymetric surfaces were projected in WGS84 / UTM zone 57S (EPSG:32757) coordinate reference system at varying resolutions. Bathymetry datasets were collated, and maps produced in ArcGIS Pro v2.8.3. Water column data files (.wcd) were not processed onboard. Additional information regarding this dataset is contained in the "NIWA Voyage Report 2022007WN.pdf". The report is available from Geophysical Survey and Mapping (GSM) group at CSIRO upon request.

This record describes multibeam echosounder data collected on RV Investigator voyage IN2022_V07, HALO - Halimeda bioherm Origins, function and fate in the northern Great Barrier Reef." The voyage took place between August 15, 2022 and September 7, 2022 (AEST), departing from Brisbane and returning to Cairns. Piggyback project: Dinoflagellates & broader planktonic assemblage observation. The Dual-Head Kongsberg EM2040c multibeam echosounder was used to acquire seafloor bathymetry, backscatter information and watercolumn backscatter at 3 focused site north of Cairns. An additional site, Lowry passage, was also systematically surveyed with the system. The EM2040c provides a 1.3 degree by 1.3 degree angular resolution. The echosounder's nominal frequency is 300 kHz and it operated in dual-head single swath mode. Data are stored in *.all raw format for bathymetry and backscatter and *.wcd format for watercolumn backscatter at CSIRO. There are 701 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. Predicted tides calculated in AusTides 2022 were applied to the processed data relative to MSL. 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.