Geological activity in Antarctica poses a potentially significant but little-understood threat to major cities in Australia.

A tsunami warning was issued in 1998, when an earthquake measuring 8.2 on the Richter scale occurred deep beneath the ice floes near the Balleny Islands about 2000 km south of Hobart.

This earthquake was ten times as powerful as the geological movements which caused the devastating tsunami in Papua-New Guinea last year according to Dr Dietmar Müller, of the School of Geosciences at the University of Sydney.

Dr Müller Muller said that the 1998 earthquake was caused by a massive movement of two tectonic plates as they grated against each other.

"This sort of movement can be very damaging, but it does not normally cause tsunamis," he said.

"But if one plate had ridden up over the top of another, as in PNG, it could have generated a seismic sea wave, travelling north towards Hobart and other south-facing cities of Australia.

"These waves travel at the speed of a jet plane, up to 950 kph.  As they reach the shallower water near land, the waves can grow taller.

Müller said some waves have reached 15 metres in height.  Waves carrying such immense volumes of water at such speeds would cause devastation in coastal, low-lying areas.

Fortunately, the recently announced federal government's budget includes $15.54 million in the 2000/01 financial year for the Australian Geological Survey Organization for its share of work in mapping the Australian Antarctic Territory extended continental shelf.

"What will be important to maximise this programme's benefit for Australia is to fund a project that assesses the tectonic risks associated with Antarctica based on these new data.

Müller recently won the Fresh Science Award at ScienceNOW! for his presentation on the formation of Antarctica and New Zealand. He will undertake a study tour of the UK later this year as his award, courtesy of the British Council.