South Tasman Rise

The South Tasman Rise is an area of seafloor that lies 550 km south of Hobart, Tasmania in the Southern Ocean where water depths are about 1,500 metres. The South Tasman Rise is also known as the Tasmania Ridge or South Tasmania Ridge.

The South Tasman Rise is a sunken land bridge that used to connect Tasmania (and by extension, the rest of Australia) to Antarctica. It served as one end of the wider Antarctic land bridge, and existed as a terrestrial connection from the Late Cretaceous (about 96 million years ago, when rifting started to significantly narrow connections between Antarctica and Australia) to the early-mid Eocene (about 50 million years ago). It started to rapidly submerge over the next few million years.

Exploration of this oceanic region has taken place via sonar, gravity field, magnetic field, a few drill holes and deliberate or accidental dredging of rocks up to the surface.