Off with a rumble, not a bang: Tiwi Islands struck by two ‘shallow, interesting’ seismic events

In the past 20 years, the Tiwi Islands have had a total of 14 earthquakes, but on New Year’s Eve in 2024 there were two in one day. Find out more.

The Tiwi Islands have rounded out 2024 with a rather shaky finish after being struck by two earthquakes on the last day of the year.

Fortunately, both of the quakes were below a three magnitude, meaning they were recorded by seismographs, but hardly noticed by anyone on the ground.

Geoscience Australia senior seismologist Hadi Ghasemi said having two earthquakes on the Tiwi Islands in just one day was very interesting considering the area’s seismic history.

“It’s not surprising to see earthquakes anywhere in Australia, but for that particular region over the past 20 years in the radius of 200km from the epicentre of the Tiwi events, we have recorded 14 events,” he said.

A 2.8 earthquake struck Melville Island in the Tiwi Islands on December 31, 2024. Picture: Geoscience Australia

“That would translate to less than one event every year, which is not a lot so I wouldn’t call it a very seismic region of Australia.

“But to have two in one day is very interesting.”

The first earthquake of the day originated at 11.02am, had a magnitude of only 2.5, and an epicentre near to central Bathurst Island.

The second earthquake originated much closer to the turn of the year at 11.43pm, had a slightly higher magnitude of 2.8, and an epicentre close by to Dongau Creek on Melville Island.

Mr Ghasemi said these two events were pretty uniform for the region.

A 2.5 earthquake struck Bathurst Island in the Tiwi Islands on December 31, 2024. Picture: Geoscience Australia

“They are fairly small, the largest one has been magnitude 3.2 so they’re very small, shallow events which is typical for the Australian continent,” he said.

“There are many factors that would contribute to the impact of an earthquake, so if it is very close to urban environments, it would be very different to if it was in the middle of nowhere.

“Given the size of the earthquakes, even if it was very close to a built environment, I wouldn’t expect much damage because the level of shaking would be low to moderate ground shaking, which wouldn’t cause any significant damage to buildings of good design.”

Originally published as Off with a rumble, not a bang: Tiwi Islands struck by two ‘shallow, interesting’ seismic events