M5.0 Earthquake in the Samoa Islands region — December 4, 2022
2022-12-04 23:38:18 UTC (2022-12-04) · approx. 12:38 PM UTC-11 local
On December 4, 2022 at 23:38 UTC, a magnitude 5.0 shallow crustal earthquake struck in the Samoa Islands region, at a depth of 17.4 km and coordinates -15.5201°, -171.6683°. The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 59 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 385, placing it among routine seismic activity. The nearest populated place is Leone (population 4,050).
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.
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
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 | 71,576 |
Earthquake Details
-171.6683°E
Technical Information
Common Questions
How strong was the magnitude 5.0 earthquake in the Samoa Islands region?
The magnitude 5.0 earthquake that struck in the Samoa Islands region on December 4, 2022 at 23:38 UTC had a depth of 17.4 km. For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at -15.5201°, -171.6683°, which is in the Samoa Islands region. The nearest populated place is Leone (population 4,050).
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.0 earthquakes can continue for days to weeks and gradually diminish over time.
Actions
Location
Authoritative source: USGS event page (event ID: us6000j6xw). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2022, December 4, 2022). M5.0 Earthquake in the Samoa Islands region — December 4, 2022. Retrieved February 11, 2023 from https://www.earthquaketracker.org/earthquakes/event/us6000j6xw/