M5.3 Earthquake in the Fiji region — August 31, 2021
2021-08-31 10:04:53 UTC (2021-08-31) · approx. 10:04 PM UTC-12 local
Felt by 2 people across nearby locations.
On August 31, 2021 at 10:04 UTC, a magnitude 5.3 deep-focus earthquake struck in the Fiji region, at a depth of 550.4 km and coordinates -18.0858°, -178.2538°. The earthquake was reported felt by 2 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 1.1 (weak). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected.
Physical scale: An earthquake of magnitude 5.3 releases seismic energy equivalent to roughly 1 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.7 km — a useful intuition for the size of the slip patch on the fault.
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
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 2 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-178.2538°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 5.3 earthquake in the Fiji region?
The magnitude 5.3 earthquake that struck in the Fiji region on August 31, 2021 at 10:04 UTC had a depth of 550.4 km. It was felt by 2 people with maximum shaking intensity of MMI 1.1 (weak). For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at -18.0858°, -178.2538°, which is in the Fiji region. View all earthquakes in Fiji.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.3 earthquakes can continue for days to weeks and gradually diminish over time.
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Location
Authoritative source: USGS event page (event ID: us7000f65t). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, August 31, 2021). M5.3 Earthquake in the Fiji region — August 31, 2021. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000f65t/