This record describes multibeam echosounder data collected on Bluefin voyage BF2019_V01, 'Hydrographic Survey of the Freycinet, Huon and Tasman Fracture Australian Marine Parks' which departed Hobart, Tasmania on the 8th March 2019 and returned to Beauty Point, Tasmania on the 22nd March 2019.
CSIRO’s Geophysical Survey and Mapping, Shallow Survey Facility (SSF) was contracted by the Institute for Marine and Antarctic Studies (IMAS) of the University of Tasmania (UTAS) in collaboration with Parks Australia, to undertake a 2 week hydrographic survey of the Freycinet Australian Marine Park to complete surveying of the Park out to approximately 300 m. Depending on weather conditions further surveying of the Huon and Tasman Fracture sites could also be attempted. Two sites, Pedra and South West Cape survey areas, were undertaken for comparison data outside of Marine Park areas.
Nick Dando from Geoscience Australia (GA) mobilised their Kongsberg EM2040c Mulitbeam Echosounder (MBES) system onboard the MV Bluefin in Hobart on Thursday and Friday 7-8 March with assistance from Stuart Edwards, Craig Davey and Bernadette Heaney, CSIRO. Divers from IMAS attached the transducer to the hull of the ship.
The GA system also included a POSMV navigation system, a Valeport sound velocity profiler (and a spare profiler) Bridge display laptop and Bridge display screen.
The Kongsberg EM2040c multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter at the Freycinet, Huon and Tasman Fracture Australian Marine Parks surrounding south and south eastern Tasmania. The EM2040c provides a 1.3° by 1.3° transmit and receive angular resolution respectively. The echosounder's nominal frequency was 300 kHz and was operated in dual swath mode. Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. 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 final processed dataset. Instead the data was mapped to the ellipsoid (GPS Height) and thereafter reduced to AHD (Australian Height Datum) using the AusGeoid09 model. 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 reports. Additional data products may be available on request.
