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.
