Shallow M5.9 earthquake hits Pacific-Antarctic Ridge
A shallow M5.9 earthquake occurred on the Pacific-Antarctic Ridge at 11:18 UTC on April 6, 2026. The quake originated at a depth of 10.0 km (6.2 miles) at coordinates 55.0°S, 129.1°W, based on USGS data.
The Pacific-Antarctic Ridge is a remote underwater tectonic boundary between the Pacific and Antarctic plates, far from any populated land masses. The closest significant land is thousands of kilometers away, and the region is devoid of towns or infrastructure.
There is no populated coastline or major infrastructure in the immediate vicinity of the epicenter. The surrounding area is characterized entirely by open ocean, with only scientific research vessels or deep-sea monitoring stations occasionally present.
There is no tsunami threat associated with this earthquake, based on its offshore location and available data.
USGS issued a green alert for this event, indicating a low likelihood of casualties or damage. The maximum estimated intensity was 0, and the significance index is 536 (on a scale that runs through 1 000), based on magnitude, felt reports, and estimated impact.
The Pacific-Antarctic Ridge is an active spreading center marking the boundary between the Pacific and Antarctic tectonic plates. It is known for frequent moderate to strong seismicity, primarily involving shallow undersea earthquakes due to tectonic divergence.
This information was last updated at 12:02 UTC on April 6, 2026.