Significant M5.5 Earthquake struck on Thursday Evening in the Bismarck Sea 138km from Lae (Papua New Guinea).

Written by Earthquakelist.org on September 19th, 2024. Last updated October 15th, 2024.

A significant M5.5 earthquake struck in the Bismarck Sea 138 kilometer from Lae, Papua New Guinea in the evening of Thursday September 19th, 2024. Shaking may have been felt by a total of 1.2 million people.

Earthquake Summary

This earthquake hit under water in the Bismarck Sea, 30 kilometers (19 mi) off the coast of Papua New Guinea, 138 kilometer north-northeast of Lae in Morobe. The center of this earthquake had an intermediate depth of 193 km.

Date and Time:	Sep 19, 2024 18:41 (Port Moresby Time) - Sep 19, 2024 08:41 Universal Time.
Location:	138 km NNE of Lae, Morobe, Papua New Guinea. Coordinates 5°34'15"S 147°27'22"E.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 5.5 Detected by 38 stations. Maximum Error Range ±0.05 .
Depth:	193 km (120 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 1.2 million people exposed to shaking

This earthquake may have been felt by around 1.2 million people. That is the expected population size of the area exposed to a level of shaking of II or higher on the Modified Mercalli scale according to the USGS.

Weak shaking and probably no damage may have been experienced by an estimated 908,300 people. At III, it is the highest MMI level this earthquake has caused. All exposure to shaking was within the borders of Papua New Guinea .

People	MMI Level	Shaking	Damage
0	I	Not noticable	None
281,000	II	Very weak	None
908,300	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 Papua New Guinea . Lae in Morobe, Papua New Guinea is the nearest significant place from the epicenter. The earthquake occurred 138 kilometer (86 mi) north-northeast of Lae. The intensity of shaking and damage in Lae is estimated to be around level III on the Modified Mercalli Intensity scale (weak shaking, probably 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)
138 km (86 mi) SSW from epicenter	Lae Morobe, Papua New Guinea.	III Weak
189 km (117 mi) W from epicenter	Madang Madang, Papua New Guinea.	III Weak
203 km (126 mi) SSW from epicenter	Bulolo Morobe, Papua New Guinea.	III Weak
236 km (147 mi) WSW from epicenter	Goroka Eastern Highlands, Papua New Guinea.
297 km (185 mi) E from epicenter	Kimbe West New Britain, Papua New Guinea.

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 III.

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 2 people

People that feel an earthquake may report their experience to the US Geographic Survey. Currently, 2 people have reported shaking in 2 places in 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:

Kainantu, Eastern Highlands, Papua New Guinea: 1 person.
Mount Hagen, Western Highlands, Papua New Guinea: 1 person.

3 Aftershocks detected

This main shock was followed by 3 smaller aftershocks. At a distance of 68 km (42 mi) east of this earthquake, an aftershock struck 3 days later. It measured a magnitude of 4.1

In the days before this main shock, 1 smaller foreshock was detected. A 4.3 magnitude earthquake hit 1 day earlier nearby.

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 4.3	1 day earlier Sep 18, 2024 11:41 (Port Moresby Time)	37 km (23 mi) SW from Main Shock.
Main Shock This Earthquake	M 5.5	Sep 19, 2024 18:41 (Port Moresby Time)	-
Aftershock	M 4.1	1 day later Sep 21, 2024 00:37 (Port Moresby Time)	13 km (8 mi) W from Main Shock.
Aftershock	M 4.1	1 day later Sep 21, 2024 00:37 (Port Moresby Time)	13 km (8 mi) W from Main Shock.
Aftershock	M 4.1	3 days later Sep 22, 2024 12:49 (Port Moresby Time)	68 km (42 mi) E from Main Shock.

More earthquakes coming?

The risk of aftershocks decreases rapidly over time. Usually, aftershocks are at least one order of magnitude lower than a main shock.

In only six percent of cases, significant earthquakes are followed by a larger main shock, making the current earthquake a foreshock. While the chance of this happening is not so large, it is adviced to maintain cautiousness in the hours and days following a major earthquake.

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 September 11th, 2024, when a 6.3 magnitude earthquake hit 279 km (173 mi) further north-northwest. An even stronger magnitude 7.6 earthquake struck on September 10th, 2022.

In total, 82 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 2 months.

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 193 km (120 mi). Earthquakes this deep in the earth are unlikely to trigger a tsunami.

Sources

Last updated 15/10/24 12:28 (). 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.