On Thursday Evening a Significant M5.5 Earthquake struck in the South Pacific Ocean 288km from Apia (Samoa).

Written by Earthquakelist.org on February 20th, 2025. Last updated March 14th, 2025.

A significant Magnitude 5.5 earthquake struck in the South Pacific Ocean 288 kilometer from Apia, Samoa just before midnight of Thursday February 20th, 2025. Shaking may have been felt by a total of 40 thousand people.

Earthquake Summary

This earthquake hit under water in the South Pacific Ocean, 233 kilometers (145 mi) off the coast of Samoa, 288 kilometer southwest of Apia in Tuamasaga. The center of this earthquake had an intermediate depth of 107 km.

Date and Time:	Feb 20, 2025 23:31 (Apia Time) - Feb 20, 2025 10:31 Universal Time.
Location:	288 km SW of Apia, Tuamasaga, Samoa. Coordinates 15°21'5"S 173°56'23"W.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 5.5 Detected by 4 stations. Maximum Error Range ±0.08 .
Depth:	107 km (66 mi) An intermediate depth.
Max. Intensity:	IV Light On the Modified Mercalli Scale.
Tsunami Risk:	Tsunami very unlikely Earthquakes under MAG-6.5 at depths deeper than 100km are very unlikely to cause tsunami's. Always stay cautious - More info here.

Minimal impact predicted

Based on scientific estimates by the US Geographic Survey (USGS), the risk of high fatalities for this earthquake is classified at level GREEN (low). They expect an 65% likelyhood of between 0 and 1 fatalities, and a 96% chance that the number of fatalities falls no higher than 10.

The USGS classifies the economic impact of this earthquake at level GREEN (low). They expect an 65% likelyhood of between 0 and 1 million US Dollars in economic damage and impact, and a 96% chance that the economic impact of this earthquake falls no higher than 10 million USD.

Roughly 40 thousand people exposed to shaking

The USGS has published a report estimating the number of people exposed to this earthquake. Acoording to their analysis, roughly 40 thousand have been exposed to shaking at an MMI level of II or higher.

The highest earthquake impact level for this earthquake is III, which corresponds with weak shaking and probably no damage. Roughly 14,420 people are expected to be exposed to this level. Intensity level II was experienced by the majority of people (around 20 thousand). In their region, very weak shaking and no damage can be expected.

People in 3 countries have been exposed to shaking. In Samoa , around 40 thousand people, with impact levels up to III (weak shaking, probably no damage). Shaking was experienced by inhabitants of Tonga too.

People	MMI Level	Shaking	Damage
0	I	Not noticable	None
22,210	II	Very weak	None
14,420	III	Weak	Probably none
0	IV	Light	Likely none
0	V	Moderate	Very light
0	VI	Strong	Light
0	VII	Very Strong	Moderate
0	VIII	Severe	Moderate to heavy
0	IX	Violent	Heavy
0	X	Extreme	Very heavy

Nearby towns and cities

This earthquake may have been felt in Samoa . Apia in Tuamasaga, Samoa is the nearest significant place from the epicenter. The earthquake occurred 288 kilometer (179 mi) southwest of Apia.

Overview of nearby places

Cities and Towns around the epicenter of this earthquake.
Distance	Place
288 km (179 mi) NE from epicenter	Apia Tuamasaga, Samoa.

Earthquake Intensity Map

The graph below overlays a map of the region around the epicenter with earthquake intensity data provided by the US Geographic Survey. The highest intensity level detected for this earthquake is IV.

I Not felt

II Weak

III Weak

IV Light

V Moderate

VI Strong

VII Very Strong

VIII Severe

IX Violent

X Extreme

Earthquake Intensity Map based on Shakemap Data provided by USGS.

Shaking reported by 4 people in 2 countries

People that feel an earthquake may report their experience to the US Geographic Survey. Currently, 4 people have reported shaking in 4 places in 2 countries (Samoa, Tonga).We keep updating this article as more ground reports become available. You may report that you felt this earthquake here.

Places with most reports:

Apia, Apia Urban Area, Samoa: 1 person.
Niusuatia, Rest of Upolu, Samoa: 1 person.
Vaigalu, Rest of Upolu, Samoa: 1 person.
Neiafu, Vavaʿu, Tonga: 1 person.

Aftershocks detected

In the days before this main shock, 2 smaller foreshocks were detected. Nearby this earthquake a foreshock struck 3 hrs earlier. It measured a magnitude of 4.7

Overview of foreshocks and aftershocks

Detected MAG2.5+ earthquakes within within 100km (62 mi), that occurred in the three days before and after the main shock.
Classification	Magnitude	When	Where
Foreshock	M 4.5	2 days earlier Feb 19, 2025 04:24 (Apia Time)	97 km (60 mi) ENE from Main Shock.
Foreshock	M 4.7	3 hrs earlier Feb 20, 2025 20:20 (Apia Time)	85 km (53 mi) NW from Main Shock.
Main Shock This Earthquake	M 5.5	Feb 20, 2025 23:31 (Apia Time)	-

More earthquakes coming?

Aftershocks are usually at least 1 order of magnitude less strong than main shocks. The more time passes, the smaller the chance and likely strength of any potential aftershocks.

The chance that a significant earthquake like this one is followed by an even larger earthquake is not so large. On average, scientists estimate a 94% chance that a major earthquake will not be followed by an even larger one. It is still adviced to be aware of this risk

Read: How to Stay Safe during an Earthquake (cdc.gov).

Earthquakes like this happen often in the region

Earthquakes of this strength are very common in the region. This is the strongest earthquake to hit since July 15th, 2024, when a 5.7 magnitude earthquake hit 190 km (118 mi) further south-east. An even stronger magnitude 7.6 earthquake struck on May 10th, 2023.

In total, 92 earthquakes with a magnitude of 5.5 or higher have been registered within 300km (186 mi) of this epicenter in the past 10 years. This comes down to an average of once every month.

Tsunami very unlikely

DISCLAIMER: We strongly suggest to closely monitor advice from local authorities with regards to tsunami risks. Our analysis is based on automatically collected data from external sources, and these might contain mistakes. In addition, earthquakes can cause landslides that may lead to a tsunami, or be a followed by another, potentially stonger, earthquake.

For a serious tsunami to occur, earthquakes usually need to have a magnitude of at least 6.5 and occur at a shallow depth of maximum 100km. Neither are the case with this earthquake. However always stay cautious and monitor advice from local authorities.

Tsunami Risk Factors

Factor	Under Sea?	MAG-6.5 or stronger?	Shallow depth?
Explanation	Almost all tsunami's are caused by earthquakes with their epicenter under sea or very near the sea. However stay cautious in coastal areas as earthquakes on land may cause landslides into sea, potentially still causing a local tsunami.	Under MAG 6.5: Very unlikely to cause a tsunami. MAG 6.5 to 7.5: Destructive tsunami's do occur, but are uncommon. Likely to observe small sea level changes. MAG 7.6+: Earthquakes with these magnitudes might produce destructive tsunami's.	Most destructive tsunami's are caused by shallow earthquakes with a depth between 0 and 100km under the surface of the earth. Deeper tsunami's are unlikely to displace to ocean floor.
This Earthquake	This earthquake appears to have struck under the sea.	Not this earthquake. This earthquake had a magnitude of 5.5. Earthquakes of this strength are unlikely to trigger a tsunami.	Not this earthquake. This earthquake occurred at a depth of 107 km (66 mi). Earthquakes this deep in the earth are unlikely to trigger a tsunami.

Sources

Last updated 14/03/25 12:58 (). This article is automatically generated based on available data. We keep checking multiple sources for additional information. This article gets updated as new details on this earthquake become available.