Australasian Science: Australia's authority on science since 1938

Australia’s Tsunami History Revised

One-hundred-and-forty-five modern and prehistoric tsunami events have struck Australia, according to a database that has been updated by Prof James Goff and Dr Catherine Chagué-Goff of the University of NSW.

“Our research has led to an almost threefold increase in the number of events identified – up from 55 in 2007. NSW has the highest number of tsunamis in the database, with 57, followed by Tasmania with 40, Queensland with 26 and Western Australia with 23,” Goff says.

“Historical documents indicate that up to 11 possible tsunami-related deaths have occurred in Australia since 1883. This is remarkable, because our tsunami-prone neighbour, New Zealand, has only one recorded death.”

Goff and Chagué-Goff scoured scientific papers, newspaper reports, historical records and other tsunami databases to update the 2007 Australian database, with the results now published in Progress in Physical Geography. “And it is still incomplete. Much more work needs to be done, especially to identify prehistoric events and those on the east coast… The geographical spread of events and deaths suggests the east coast faces the most significant risk,” says Goff.

While the 2007 database identified the country’s largest tsunami as one that hit Western Australia following an earthquake off Sumba Island in Indonesia on 19 August 1977, this rating was based on wrong information about its wave height. Giant wave heights of about 13 metres have also been attributed to a possible tsunami on 8 April 1911 in Warrnambool, Victoria, but no hard evidence is available to back this up.

The study identified three prehistoric events that had an impact across the whole of the south-west Pacific Ocean: an asteroid impact 2.5 million years ago, and large earthquakes about 2900 years ago and in the mid-15th century.

The largest recorded inundation event in Australia was caused by an earthquake off Java in Indonesia on 17 July 2006, which led to a tsunami that reached up to 7.9 metres above sea level on land at Steep Point in Western Australia.

Australia was also the site of the oldest known tsunami in the world – an asteroid impact that occurred 3.47 billion years ago in what is now the Pilbara district of Western Australia.