Tasman Seamounts, Australia | John Seach

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Tasman Sea, South East Australia

This Tasman line of fire is created by a mantle plume which gives rise to hotspot volcanoes underwater. The Tasman line of fire extends from Mt Erebus in Antarctica along the South East coast of Australia into the Tasman sea. The line is 4000 km long and fused about 55 million years ago, joining Lord Howe Island to the Australian plate. Mt Erebus now sits over the Tasman mantle plume.

The Tasmanian Seamounts Reserve covers about 370 square kilometres, and 15 of the 70 seamounts in the zone. Bottom trawling and petroleum and mineral exploration are banned. It is a protected area, declared in 1999, with 70 extinct volcanoes 170 kilometres south of Hobart.

Major seamounts are Queensland, Britannia, Derwent-Hunter, Lord Howe Island, Barcoo, Taupo, Gascoyne. Heemskirk, Zeehan, Soela.

Further reading
Richards et al. Geochemistry, Geophysics, Geosystems19(10), pp.3870-3891.

Eruptions of Tasman Seamounts

56 million years ago (northern seamounts)
7 million years (southern seamounts)