The Department of the Environment, Water, Heritage and the Arts (DEWHA) has identified as key ecological features (KEFs) numerous geomorphic features or regionally important species or habitats in the northwest marine region. This process supports the department's establishment of the development of Marine Bioregional Plans and a National Representative System of Marine Protected Areas (NRSMPA). A total of ten KEFs are included in this study of which seven lie in the deep-sea where information on biodiversity and ecosystems is scarce. The ten KEFs are: Wallaby Saddle, Cuvier Abyssal Plain, Cape Range Canyons, Exmouth Plateau, Argo Abyssal Plain, Bowers and Oates Canyons, Scott Plateau, Scott Reef, the Holocene Coastline, and Glomar Shoals. Geoscience Australia was engaged to investigate habitat heterogeneity of these KEFs utilising its existing expertise in habitat mapping and surrogacy.