M6.1 Earthquake 157 km ESE of Alo, Wallis and Futuna — February 18, 2021
2021-02-18 15:30:47 UTC (2021-02-18) · approx. 3:30 AM UTC-12 local
Felt by 2 people across nearby locations.
On February 18, 2021 at 15:30 UTC, a magnitude 6.1 shallow crustal earthquake struck 157 km ESE of Alo, Wallis and Futuna, at a depth of 3.7 km and coordinates -14.8373°, -176.7574°. The earthquake was reported felt by 2 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.8 (light). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. The nearest populated place is Alo (population 239).
Physical scale: An earthquake of magnitude 6.1 releases seismic energy equivalent to roughly 21 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 9.7 km — a useful intuition for the size of the slip patch on the fault.
Nearest Populated Places
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
Population exposure (USGS PAGER)
Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.
| Shaking intensity (MMI) | Description | Population exposed |
|---|---|---|
| MMI 3 | weak | 15,919 |
| MMI 4 | light | 89 |
Earthquake Details
-176.7574°E
Technical Information
Common Questions
How strong was the magnitude 6.1 earthquake near Alo, Wallis and Futuna?
The magnitude 6.1 earthquake that struck 157 km ESE of Alo, Wallis and Futuna on February 18, 2021 at 15:30 UTC had a depth of 3.7 km. It was felt by 2 people with maximum shaking intensity of MMI 3.8 (light). For context, this was a strong earthquake capable of causing significant damage.
Where did the earthquake occur?
The earthquake epicenter was located at -14.8373°, -176.7574°, which is 157 km ESE of Alo, Wallis and Futuna. The nearest populated place is Alo (population 239).
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 6.1 earthquakes can continue for weeks to months and gradually diminish over time.
Actions
Authoritative source: USGS event page (event ID: us6000dip3). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, February 18, 2021). M6.1 Earthquake 157 km ESE of Alo, Wallis and Futuna — February 18, 2021. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000dip3/