Eastern Victoria Hit by Earthquake Aftershock

A 3.0-magnitude earthquake aftershock has been recorded in south-eastern Victoria, three weeks after an initial late-night quake woke thousands. Geoscience Australia said the quake hit at a shallow depth of 5 kilometres just after 2pm, and the epicentre was at Kardella South, near Korrumburra.

The federal agency's website cited more than 200 felt reports in the area — far fewer than the October 3 initial quake. There have been no reports of injuries or damage.

Respondents to Geoscience Australia registered felt reports close to the epicentre between 2pm and 3.30pm Saturday, as well as the Latrobe Valley and suburban Melbourne.

What is an aftershock?

Monash University's School of Earth, Atmosphere and Environment earthquake geologist Dee Ninis said aftershocks were often registered some time after an earthquake. "Aftershocks are felt hours, days, even weeks after an initial earthquake. Because it occurred in the same area as the earthquake earlier this month and was of a lower magnitude than the initial earthquake, it is an aftershock," Dr Ninis said.

"Often there's hundreds of aftershocks after an earthquake and the majority are usually too small to be felt."

Region of heightened seismic activity

The Gippsland Basin is a region of heightened seismic activity relative to some other regions. Back in 2009, there was a magnitude 4.7 which was followed by a similar magnitude earthquake about two weeks later. There was also a magnitude 4.4 quake in the Gippsland basin in 2011.

Dr Ninis said the October 3 and 17 Gippsland tremors were "unrelated seismic events" to the 2021 Woods Point earthquake, which rattled greater Melbourne five years ago. The magnitude 5.9 earthquake, which struck in September 2021, was centred near the tiny town near Mansfield, about 130 kilometres north-east of Melbourne.

Local community still feeling the effects

South Gippsland Shire mayor Nathan Hersey said he hadn't personally noticed the latest aftershock but added that seismic activity remained a hot topic of conversation locally. "People are still talking about the initial earthquake and there's been several aftershocks since," Cr Hersey said.

"I was at a community breakfast in Arawata, which is the town at the epicentre of the initial earthquake, and people are still talking about it weeks down the track. Earthquakes are a fascinating topic."