Korumburra shakes again

18 March 2009

A magnitude 4.6 earthquake occurred five km north-west of the town of Korumburra, 96 km south-east of Melbourne, at 4:28pm today.

"We have had reports from people up to 200 kilometres away who have felt the earthquake, but no reports of damage or injury at this stage," said Duty Seismologist Dr Spiro Spiliopoulos.

"An earthquake of the same size occurred in the same spot earlier this month, on 6 March. While this activity is unusual, it has been known to occur in other locations.

"On average, in Victoria there is an earthquake of this size or larger every two or three years and they can occur anywhere in Victoria. The largest earthquake in Australia is estimated at a magnitude of 7.2 in 1941 in Meeberrie, WA," he said.

"This type of event, called an intraplate earthquake, happens because of the build up of stress in the Earth's crust, which is caused by the movement of the tectonic plates. This is part of the Earth's natural dynamic processes. The Australian continent is part of the Indian-Australian plate which is being pushed slowly north-east at approximately 7cm per year, resulting in collisions with the Eurasian, Philippine and Pacific plates. The stress from these collisions is released during an earthquake," said Dr Spiliopoulos

Geoscience Australia monitors earthquakes 24/7, using information from more than 80 seismograph stations which detect movements within the Earth. All this information, or data, is transmitted from these stations scattered around Australia to the central office in Canberra where seismologists (earthquake scientists) determine the location, magnitude and depth of the earthquake.

While Geoscience Australia's monitoring system determines the exact location, magnitude and time of an earthquake, information from the community provides valuable information about what it "felt" like.

There is a simple online earthquake report form that can be filled in on the Geoscience Australia website. It includes a series of questions to obtain information about shaking windows, loud noises or any immediate building damage. This information assists seismologists in gaining a greater understanding of this naturally occurring Earth process.

Topic contact: media@ga.gov.au Last updated: October 4, 2013