Shallow M6.5 Earthquake struck on Wednesday Night in the Bismarck Sea 133km from Wewak (Papua New Guinea).

Written by Earthquakelist.org on May 20th, 2025. Last updated June 14th, 2025.

In the Bismarck Sea 133 kilometer from Wewak, Papua New Guinea, a shallow and strong MAG-6.5 earthquake occurred in the night of Wednesday May 21st, 2025. The USGS has indicated there is a potential risk at tsunami's following this earthquake.

Earthquake Summary

This earthquake hit under water in the Bismarck Sea, 32 kilometers (20 mi) off the coast of Papua New Guinea, 133 kilometer east of Wewak in East Sepik. The center of this earthquake had a very shallow depth of 17 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	May 21, 2025 01:05 (Port Moresby Time) - May 20, 2025 15:05 Universal Time.
Location:	133 km east of Wewak, East Sepik, Papua New Guinea. Coordinates 3°45'27"S 144°48'42"E.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 6.5 Detected by 33 stations. Maximum Error Range ±0.043 .
Depth:	17 km (10 mi) A very shallow depth.
Max. Intensity:	VIII Severe On the Modified Mercalli Scale.
Tsunami Risk:	Potential tsunami risk The USGS has indicated there is a potential risk at tsunami's following this earthquake. Always stay cautious - More info here.

Potential tsunami risk

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.

There is a potential tsunami risk in the aftermath of this earthquake, immediately evacuate to higher grounds away from coastal areas and monitor advice from local authorities. The US Geographic Survey organization has indicated a potential risk for tsunami's following this earthquake.

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.	This earthquake had a magnitude of 6.5. Earthquakes of this strength could trigger a tsunami.	This earthquake occurred at a depth of of 17 km (10 mi). Earthquakes this shallow could trigger a tsunami.

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 86% likelyhood of between 0 and 1 million US Dollars in economic damage and impact, and a 99% chance that the economic impact of this earthquake falls no higher than 10 million USD.

Roughly 1.7 million people exposed to shaking

The USGS has published a report estimating the number of people exposed to this earthquake. Acoording to their analysis, roughly 1.7 million have been exposed to shaking at an MMI level of II or higher.

The highest earthquake impact level for this earthquake is VIII, which corresponds with severe shaking and likely moderate to heavy damage. Roughly 150 people are expected to be exposed to this level. Intensity level IV was experienced by the majority of people (around 1.2 million). In their region, light shaking and likely no damage can be expected. All exposure to shaking was within the borders of Papua New Guinea .

People	MMI Level	Shaking	Damage
0	I	Not noticable	None
0	II	Very weak	None
780	III	Weak	Probably none
1,226,000	IV	Light	Likely none
365,600	V	Moderate	Very light
106,200	VI	Strong	Light
24,140	VII	Very Strong	Moderate
150	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 Papua New Guinea . Wewak in East Sepik, Papua New Guinea is the nearest significant place from the epicenter. The earthquake occurred 133 kilometer (83 mi) east of Wewak. The intensity of shaking and damage in Wewak is estimated to be around level IV on the Modified Mercalli Intensity scale (light shaking, likely no damage).

A complete list of nearby places is included below. Estimated intensity data (MMI) sourced from a shake-map published by the US Geographic Survey is shown where available (cities without data probably experienced little impact).

Overview of nearby places

Cities and Towns around the epicenter of this earthquake.
Distance	Place	Intensity (MMI)
133 km (83 mi) W from epicenter	Wewak East Sepik, Papua New Guinea.	IV Light
195 km (121 mi) SE from epicenter	Madang Madang, Papua New Guinea.	V Moderate
242 km (150 mi) SSW from epicenter	Mount Hagen Western Highlands, Papua New Guinea.
267 km (166 mi) SSE from epicenter	Goroka Eastern Highlands, Papua New Guinea.
295 km (183 mi) SSW from epicenter	Mendi Southern Highlands, Papua New Guinea.
409 km (254 mi) SE from epicenter	Lae Morobe, Papua New Guinea.
433 km (269 mi) SSE from epicenter	Bulolo Morobe, Papua New Guinea.
474 km (295 mi) WNW from epicenter	Jayapura Papua, Indonesia.
482 km (300 mi) WNW from epicenter	Abepura Papua, Indonesia.

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 VIII.

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 12 people

People that feel an earthquake may report their experience to the US Geographic Survey. Currently, 12 people have reported shaking in 3 places, all within Papua New Guinea.We keep updating this article as more ground reports become available. You may report that you felt this earthquake here.

Places with most reports:

Angoram, East Sepik, Papua New Guinea: 10 people.
Wewak, East Sepik, Papua New Guinea: 1 person.
Kavieng, New Ireland, Papua New Guinea: 1 person.

2 Aftershocks detected

Since this main shock, 2 smaller aftershocks were detected. A 5.3 magnitude earthquake hit 5 mins later 49 km (30 mi) north-northeast of this earthquake.

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
Main Shock This Earthquake	M 6.5	May 21, 2025 01:05 (Port Moresby Time)	-
Aftershock	M 5.3	5 mins later May 21, 2025 01:10 (Port Moresby Time)	49 km (30 mi) NNE from Main Shock.
Aftershock	M 4.2	18 hrs later May 21, 2025 19:20 (Port Moresby Time)	19 km (12 mi) WSW from Main Shock.

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.

It's always adviced to be cautious of the risk of a larger shock following any significant earthquake, however this risk is fairly small. There is a roughly 94 percent change that no larger main shock will follow in the days following this earthquake.

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

Earthquakes like this are common in the region

Earthquakes of this strength occur quite regularly in the region. This is the strongest earthquake to hit since March 23rd, 2024, when a 6.9 magnitude earthquake hit 191 km (118 mi) further west-southwest. An even stronger magnitude 7 earthquake struck on April 2nd, 2023.

In total, 6 earthquakes with a magnitude of 6.5 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 2 years.

Sources

Last updated 14/06/25 00:38 (). As more information on this earthquake becomes available this article will be updated. This article is automatically composed based on data originating from multiple sources.