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

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

This earthquake was ten times as powerful as the geologicalmovements which caused the devastating tsunami in Papua-New Guinea lastyear according to Dr Dietmar Müller, of the School of Geosciencesat the University of Sydney.

Dr Müller Muller said that the 1998 earthquake wascaused by a massive movement of two tectonic plates as they grated againsteach other.

"This sort of movement can be very damaging, but it doesnot 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 northtowards Hobart and other south-facing cities of Australia.

"These waves travel at the speed of a jet plane, up to950 kph.  As they reach the shallower water near land, the waves cangrow taller.

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

Fortunately, the recently announced federal government'sbudget includes $15.54 million in the 2000/01 financial year for the AustralianGeological Survey Organization for its share of work in mapping the AustralianAntarctic Territory extended continental shelf.

"What will be important to maximise this programme's benefitfor Australia is to fund a project that assesses the tectonic risks associatedwith 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. Hewill undertake a study tour of the UK later this year as his award, courtesyof the British Council.