There are huge variations in the offshore area around Australia, with offshore plateaus the size of Victoria off the west and east coasts. When we look in detail there are rocky outcrops, deep canyons, and smooth slopes. These form habitats for a great range of bottom-dwelling organisms and fish, and could be the source of unusual organic material for new medicines. The technology is now available to map the sea bed quickly and in great detail, and this mapping has started off Australia. Swath mapping involves bouncing a fan of many narrow sonar beams off the sea bed, and interpreting the reflections to give contour maps and reflectivity maps.
Reflectivity is a rough measure of the hardness or roughness of the sea bed.
The detail is far greater in the areas swath-mapped than elsewhere. Multibeam sonar swath-mapping system on R.V. L'Atalante can map a large area of seabed very quickly. Bathymetric map of the Tasmanian offshore area, with swath-mapped areas showing much more detail. They form the habitat for blue grenadier, a commercial fish. Area west of Tasmania, showing shelf, canyons, abyssal plain and cliff 2km high.