M4.7 Earthquake 131 km NNE of Hihifo, Tonga — May 25, 2026

On May 25, 2026 at 23:36 UTC, a magnitude 4.7 shallow crustal earthquake struck 131 km NNE of Hihifo, Tonga, at a depth of 10.0 km and coordinates -14.9019°, -173.2315°. This earthquake was detected by 17 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 340, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.7 releases seismic energy equivalent to roughly 169 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.1 km — a useful intuition for the size of the slip patch on the fault.

This earthquake is part of an ongoing aftershock sequence following the magnitude 5.0 mainshock that occurred 1 day ago 141 km SSW of Gataivai, Samoa. Since the mainshock, the USGS has recorded 0 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.

The epicenter is located in Tonga, a region characterized by the Tonga-Kermadec subduction zone, where the Pacific Plate descends at up to 240 mm per year — the fastest plate convergence on Earth. The nearest mapped fault system is the Tonga Trench. View all earthquakes in Tonga.

Learn more: Magnitude scale · Aftershock sequences