Authors: Beaman, R.J., Picard, K., Miller, A.
Publication: RV Falkor surveys in Australia 2020-2021. In: Maschke, J. (Editor), Hydrospatial 2021 Conference, 16-18 Feb 2022. Australasian Hydrographic Society, Cairns, Australia.
The Schmidt Ocean Institute (SOI) operates the R/V Falkor, an 82 m long state-of-the-art oceanographic research vessel that operates year round throughout the world’s oceans. Marine scientists, students, teachers, technicians and artists from many nations conduct research onboard R/V Falkor through dedicated science expeditions. In 2020, SOI committed to operating the Falkor for a year-long series of expeditions within Australian waters involving multibeam mapping and using the ROV SuBastian for deep-water exploration and sampling. This talk will focus on the significant mapping efforts conducted by SOI and the Falkor during 2020 and early 2021, which also involved overcoming challenges due to the COVID pandemic to allow continued operations during this crisis.
The Falkor operates the Kongsberg EM302 and EM710 multibeam systems mounted on its gondola. A team of between 2-3 experienced multibeam technicians typically staff the Falkor on every expedition. At the beginning of 2020, SOI began to work directly with the AusSeabed group to allow continuous multibeam mapping during the entire circumnavigation of Australia and share the data directly with AusSeabed, linking the various planned expeditions together. Therefore from January 2020, once the Falkor entered Australian waters, the ship continuously mapped (24/7) and pausing only when ROV operations were in progress or for crew changeovers in port.
However, due to the restrictions posed by border closures and the impact on crew changeovers, SOI recruited staff from the Marine National Facility and the Australian Antarctic Division to assist their mapping team. Additionally, many of the onboard scientists and students embedded into the multibeam team to learn acoustic mapping theory, to conduct data acquisition, and apply post-processing techniques and data visualisation. This sustained mapping effort, despite the year’s significant challenges, resulted in around 200 thousand square km of new seafloor mapped within Australia’s waters – equivalent to an area nearly three times the size of Tasmania.
The Falkor safely conducted both continuous passage mapping as well as systematic mapping within diverse environments ranging from the temperate colder waters along southern Australia to warmer tropical waters in northern Australia. Mapping occurred across depths ranging from ~40 m at the shelf edge to depths over 4000 m in basins. Seafloor features, including submarine canyons, drowned reefs, underwater landslides and debris fields, and the edges of shallow coral reefs, were mapped and discovered, and in places were investigated further using the ROV SuBastian.
For example, the ‘Visioning of the Coral Sea Marine Park’ expedition mapped the steep flanks of all 30 of the remote coral reefs on the Queensland Plateau revealing numerous large collapse blocks scattered around the perimeter of these reefs, which include some of the largest atolls in the world. These discoveries by the Falkor have turned the Coral Sea Marine Park from one of the poorest-mapped offshore marine parks to one of the best mapped, together with the high-resolution ROV imagery and sample data available to understand the mesophotic and deep-water environments.
Similarly, the ‘Northern depths of the Great Barrier Reef’ expedition was the first to map systematically the continental slope offshore of Cape York, considered a frontier area and rarely visited by any vessels with mapping capabilities. The Falkor mapped and discovered a 500 m-tall detached reef, generating significant international and national media interest of the discovery within the Great Barrier Reef Marine Park, and of the Falkor’s year-long mapping efforts in Australia’s remote offshore waters.
With the objective to follow open and FAIR data principles, the Falkor aimed to conform, wherever possible to the Australian Multibeam Guidelines, while blending with SOI’s internal procedures to create metadata records, event logging, processing workflow and data archiving. This workflow continued even when the COVID pandemic started in April 2020 and no science team were allowed to be physically onboard the next expedition. Therefore, the Falkor continued mapping offshore and provided the satellite capability for the science team ashore to monitor in real time the multibeam acquisition systems and ROV vision during dives.
This high level of satellite connectivity led to the start of daily multibeam data uploads of both raw and Qimera-processed .gsf files to the AusSeabed team at Geoscience Australia. Data were processed in the cloud using CARIS HIPS&SIPS and the resulting bathymetry grids published on the AusSeabed Marine Data Portal soon after each expedition finished. The combination of experienced operators, a well-designed sonar fit out, constant feedback on the data collection, and edge mapping of previous data, resulted in large survey areas completed with few data gaps.
The Schmidt Ocean Institute’s R/V Falkor surveys in Australia are a testament to the resilience of the extended SOI crew and science crew in overcoming the significant challenges brought on by the pandemic. This allowed sustained mapping expeditions in remote areas involving use of advanced technologies, innovative crewing practices and data sharing, together with excellent outreach communications of the surveys.