Shallow M5.5 Earthquake struck on Saturday Evening in the Philippine Sea near Dededo Village (Guam).

Written by Earthquakelist.org on September 14th, 2024. Last updated September 23rd, 2024.

In the Philippine Sea 89 kilometer from Dededo Village, Guam, a shallow and significant MAG-5.5 earthquake occurred in the evening of Saturday September 14th, 2024. Around 180 thousand people have been exposed to shaking. Northern Mariana Islands is also near its epicenter.

Earthquake Summary

This earthquake hit under water in the Philippine Sea, 58 kilometers (36 mi) off the coast of Guam, 89 kilometer southwest of Dededo Village in Dededo. The center of this earthquake had a very shallow depth of 10 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	Sep 14, 2024 21:41 (Guam Time) - Sep 14, 2024 11:41 Universal Time.
Location:	89 km SW of Dededo Village, Dededo, Guam. Coordinates 13°1'56"N 144°11'27"E.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 5.5 Detected by 31 stations. Maximum Error Range ±0.056 .
Depth:	10 km (6 mi) A very shallow depth.
Max. Intensity:	V Moderate On the Modified Mercalli Scale.
Tsunami Risk:	Low tsunami risk Earthquakes under MAG-6.5 do not usually 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 180 thousand people exposed to shaking

This earthquake may have been felt by around 180 thousand 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.

An estimated 123,500 people were exposed to level IV. At this level, light shaking and likely no damage can be expected.

People in 2 countries have been exposed to shaking. In Guam , around 180 thousand people, with impact levels up to IV (light shaking, likely no damage). People were exposed to shaking in Northern Mariana Islands as well.

People	MMI Level	Shaking	Damage
0	I	Not noticable	None
0	II	Very weak	None
60,210	III	Weak	Probably none
123,500	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

2 countries can be found within 300km of the epicenter of this earthquake: Guam and Northern Mariana Islands .

The closest significant population center near the earthquake is Guam Government House in Hagatna, Guam. Guam Government House is located 78 kilometer (48 mi) southwest of the epicenter. The intensity of shaking and damage in Guam Government House is estimated to be around level IV on the Modified Mercalli Intensity scale (light shaking, likely no damage).

An overview of nearby towns and cities is available in the overview below. If places don't have intensity data available, it likely means the experienced impact in those places was fairly small.

Overview of nearby places

Cities and Towns around the epicenter of this earthquake.
Distance	Place	Intensity (MMI)
78 km (48 mi) NE from epicenter	Hagåtña Hagatna, Guam.	IV Light
78 km (48 mi) NE from epicenter	Guam Government House Hagatna, Guam.	IV Light
81 km (50 mi) NE from epicenter	Mangilao Village Mangilao, Guam.	IV Light
82 km (51 mi) NE from epicenter	Tamuning Tamuning, Guam.	IV Light
82 km (51 mi) NE from epicenter	Tamuning-Tumon-Harmon Village Tamuning, Guam.	IV Light
89 km (55 mi) NE from epicenter	Dededo Village Dededo, Guam.	IV Light
94 km (58 mi) NE from epicenter	Yigo Village Yigo, Guam.	IV Light
295 km (183 mi) NE from epicenter	Saipan Saipan, Northern Mariana Islands.

Earthquake Intensity Map

The maximum intensity (MMI Scale) caused by this earthquake is IV. The map below shows in which areas this earthquake was the most and least impactful. It is based on data from the US Geographic Survey.

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.

Aftershocks detected

This main shock was followed by 1 smaller aftershock. At a distance of 10 km (6 mi) south of this earthquake, an aftershock struck 2 days later. It measured a magnitude of 5

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 5.5	Sep 14, 2024 21:41 (Guam Time)	-
Aftershock	M 5.0	2 days later Sep 17, 2024 04:12 (Guam Time)	10 km (6 mi) S from Main Shock.

More earthquakes coming?

Earthquakes can create aftershocks. These are generally at least 1 magnitude lower than any main shock, and as time passes the chance and strength of aftershocks decreases.

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 October 20th, 2023, when a 5.7 magnitude earthquake hit 115 km (71 mi) further southwest. An even stronger magnitude 6 earthquake struck on February 13th, 2022.

In total, 22 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 6 months.

Low 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.

Based on early data it appears this earthquake was not strong enough (lower than MAG-6.5) to be likely to cause destructive tsunami's. However this earthquake appeared to have hit at a shallow depth under sea, so 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.	This earthquake occurred at a depth of of 10 km (6 mi). Earthquakes this shallow could trigger a tsunami.

Sources

Last updated 23/09/24 00:18 (). 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.