M5.0 Earthquake 233 km E of Levuka, Fiji — July 28, 2023

On July 28, 2023 at 17:38 UTC, a magnitude 5.0 deep-focus earthquake struck 233 km E of Levuka, Fiji, at a depth of 598.8 km and coordinates -17.9647°, -178.4785°. This earthquake was detected by 204 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 385, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 5.0 releases seismic energy equivalent to roughly 477 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.7 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 5.4 mainshock that occurred 7 days ago 216 km E of Levuka, Fiji. Since the mainshock, the USGS has recorded 6 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 Fiji, a region characterized by the Fiji Fracture Zone at the junction of the Pacific and Australian plates, with deep-focus seismicity from the subducted slab. View all earthquakes in Fiji.

Learn more: Magnitude scale · Aftershock sequences