AusBathyTopo (Kerguelen Plateau) 100m 2022 - A regional-scale depth model (20220004C)

This dataset contains bathymetry (depth) products from the compilation of all available source bathymetry data within the Kerguelen Plateau into a 100 m-resolution Digital Elevation Model (DEM). Heard Island and McDonald Islands are situated on the Kerguelen Plateau within the south-west Indian Ocean and lie within Australia's marine jurisdiction. Heard Island and McDonald Islands (HIMI) are surrounded by an Exclusive Economic Zone extending 200 nautical miles from their coasts and much of the Kerguelen Plateau south of Heard Island has been recognised as Australian Extended Continental Shelf by the UN Commission for the Legal Continental Shelf. The area is currently targeted by fishers licensed under the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR). The purpose of the bathymetry grid is to improve the geomorphic detail of seafloor features, including submarine volcanic hills on the top of the Kerguelen Plateau and a complex of submarine channels draining the southern flank of northern plateau. Australian Hydrographic Office-supplied single beam echo sounder bathymetry data were used to develop the general depth variation across the Kerguelen Plateau and adjacent Williams Ridge extending to the south-east of the central plateau. Deep-water multibeam bathymetry data reveal the complexity of the seafloor on Kerguelen Plateau and the surrounding abyssal plains and basins. These multibeam surveys were conducted both as systematic surveys by Research Vessel (RV) Investigator and Sonne over Williams Ridge. Other multibeam data were obtained from transit voyages that crossed through the Kerguelen Plateau and Williams Ridge area. SHOM-supplied combined multibeam and single beam data were collected around the French EEZ and approaches to Kerguelen Island, which is French territory. Austral Fisheries provided extensive crowdsourced bathymetry (CSB) data from their various blue-water fishing vessels using single beam echo sounders. These fishing vessels operate within the Kerguelen Plateau and Williams Ridge region under licence from the Australian Fisheries Management Authority. Austral Fisheries CSB date were provided to the Australian Antarctic Division (AAD) for restricted use in this project. All source multibeam and single beam bathymetry data were extensively edited as 3D point clouds to remove obvious anomalous noise, and given a consistent WGS84 horizontal datum, and where possible, an approximate MSL vertical datum prior to the grid interpolation process.