Shallow M5.6 earthquake hits Balleny Islands region

An earthquake measuring M5.6 was recorded in the Balleny Islands region at 06:57 UTC on December 20, 2025. The event originated at a depth of 10.0 km (6.2 miles), based on coordinates 172.7°E, 63.9°S.

The Balleny Islands are situated in the Southern Ocean, well south of New Zealand and Australia, remote from any major population centers or settlements.

Critical infrastructure in this region is sparse due to its remote, uninhabited nature. No significant ports, airports, or energy facilities are located nearby.

There is no tsunami threat associated with this earthquake, based on its location and available data.

USGS issued a green alert for this event, indicating a low likelihood of casualties or damage.

The maximum estimated intensity is 0, with no felt reports received. The significance index is 482 (on a scale that runs through 1 000), based on magnitude, felt reports, and estimated impact.

The Balleny Islands region lies along the boundary between the Antarctic Plate and the Australian Plate, an area known for moderate seismic activity primarily driven by plate interactions in the Southern Ocean basin.

This information was last updated at 07:19 UTC on December 20, 2025.