August 15, 1868 :
High tide had been at 5am that day, and by 8am sea levels in Sydney Harbour were dropping. Suddenly, "the waters, as if impelled by some extraordinary influence, returned up the harbour with great force", The Sydney Morning Herald reported.
Further down the coast, at Jervis Bay, the ocean was surging into Currambene Creek. "It raced back in a similar manner, sweeping away a large portion of sand that impeded navigation," the paper noted.
The tsunami that struck the New South Wales coast that day was caused by a massive earthquake strike in Chile.In total, some 37 tsunamis have been reported along the NSW coastline over the past 150 years.
From the Sydney Morning Herald :
A Macquarie University researcher, Dale Dominey-Howes, said Australia had a reputation as a region where few tsunami hit, but there have been at least 57 reported. "Relatively speaking, this is a much higher rate of occurrence than many other regions of the globe," he said.
He was surprised to find the Australian tsunami record went back 3.5 billion years, to when an asteroid hit waters in what is now central Australian desert. Rocks and debris it ripped up from the shallow sea have been identified by Australian geologists.
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