Significant M5.6 Earthquake hit in the North Pacific Ocean near Iwaki (Japan) on Friday Night.

Written by Earthquakelist.org on March 14th, 2024. Last updated April 28th, 2024.

In the North Pacific Ocean 22 kilometer from Iwaki, Japan, a significant Magnitude 5.6 earthquake occurred just after midnight of Friday March 15th, 2024. Roughly 47 million people may have felt this earthquake.

Earthquake Summary

This earthquake hit under water in the North Pacific Ocean, right off the coast of Japan (9 mi offshore), 22 kilometer east-northeast of Iwaki in Fukushima. The center of this earthquake had a quite shallow depth of 44 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	Mar 15, 2024 00:14 (Tokyo Time) - Mar 14, 2024 15:14 Universal Time.
Location:	22 km ENE of Iwaki, Fukushima, Japan. Coordinates 37°5'46"N 141°7'46"E.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 5.6 Detected by 22 stations. Maximum Error Range ±0.066 .
Depth:	44 km (27 mi) A quite 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 47 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 47 million have been exposed to shaking at an MMI level of II or higher.

Light shaking and likely no damage may have been experienced by an estimated 1,250,000 people. At IV, it is the highest MMI level this earthquake has caused. Intensity level III was experienced by the majority of people (around 46 million). In their region, weak shaking and probably no damage can be expected. All exposure to shaking was within the borders of Japan .

People	MMI Level	Shaking	Damage
0	I	Not noticable	None
14,290	II	Very weak	None
46,130,000	III	Weak	Probably none
1,250,000	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 Japan . Iwaki in Fukushima, Japan is the nearest significant place from the epicenter. The earthquake occurred 22 kilometer (14 mi) east-northeast of Iwaki. The intensity of shaking and damage in Iwaki is estimated to be around level IV on the Modified Mercalli Intensity scale (light shaking, likely no damage).

Multiple large cities are in proximity of today's earthquake. Tokyo is located 203 km to the southwest and experienced an intensity of III (weak shaking, probably no damage). Iwaki is located 22 km to the west-southwest and experienced an intensity of IV (light shaking, likely no damage). Yokohama is located 228 km to the southwest and experienced an intensity of III (weak shaking, probably 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)
22 km (14 mi) WSW from epicenter	Iwaki Fukushima, Japan.	IV Light
45 km (28 mi) NNW from epicenter	Namie Fukushima, Japan.	IV Light
48 km (30 mi) SW from epicenter	Kitaibaraki Ibaraki, Japan.	IV Light
56 km (35 mi) SW from epicenter	Takahagi Ibaraki, Japan.	IV Light
61 km (38 mi) W from epicenter	Ishikawa Fukushima, Japan.	IV Light
63 km (39 mi) NW from epicenter	Funehikimachi-funehiki Fukushima, Japan.	IV Light
68 km (42 mi) WNW from epicenter	Miharu Fukushima, Japan.	III Weak
69 km (43 mi) WNW from epicenter	Sukagawa Fukushima, Japan.	IV Light
70 km (43 mi) SW from epicenter	Hitachi Ibaraki, Japan.	IV Light
73 km (45 mi) W from epicenter	Yabuki Fukushima, Japan.	IV Light
74 km (46 mi) WNW from epicenter	Kōriyama Fukushima, Japan.	IV Light
78 km (48 mi) WSW from epicenter	Daigo Ibaraki, Japan.	IV Light
79 km (49 mi) NW from epicenter	Motomiya Fukushima, Japan.	IV Light
82 km (51 mi) NW from epicenter	Nihommatsu Fukushima, Japan.	IV Light
86 km (53 mi) SW from epicenter	Funaishikawa Ibaraki, Japan.	III Weak
88 km (55 mi) SW from epicenter	Ōmiya Ibaraki, Japan.	IV Light
93 km (58 mi) NW from epicenter	Fukushima Fukushima, Japan.	III Weak
94 km (58 mi) SW from epicenter	Hitachi-Naka Ibaraki, Japan.	III Weak
95 km (59 mi) NNW from epicenter	Hobaramachi Fukushima, Japan.	IV Light
95 km (59 mi) W from epicenter	Nasushiobara Tochigi, Japan.	III Weak
95 km (59 mi) SSW from epicenter	Katsuta Ibaraki, Japan.	III Weak
96 km (60 mi) NNW from epicenter	Yanagawamachi-saiwaichō Fukushima, Japan.	III Weak
97 km (60 mi) W from epicenter	Kuroiso Tochigi, Japan.	III Weak
100 km (62 mi) SSW from epicenter	Ōarai Ibaraki, Japan.	III Weak
100 km (62 mi) WSW from epicenter	Karasuyama Tochigi, Japan.	III Weak
101 km (63 mi) WSW from epicenter	Ōtawara Tochigi, Japan.	III Weak
103 km (64 mi) SW from epicenter	Mito Ibaraki, Japan.	III Weak
126 km (78 mi) WSW from epicenter	Utsunomiya Tochigi, Japan.	III Weak
127 km (79 mi) NW from epicenter	Yonezawa Yamagata, Japan.	III Weak
132 km (82 mi) N from epicenter	Sendai Miyagi, Japan.	III Weak
135 km (84 mi) SW from epicenter	Tsukuba Ibaraki, Japan.	III Weak
143 km (89 mi) NNW from epicenter	Yamagata Yamagata, Japan.	III Weak
148 km (92 mi) SW from epicenter	Oyama Tochigi, Japan.	III Weak
172 km (107 mi) SW from epicenter	Kashiwa Chiba, Japan.	III Weak
173 km (107 mi) SSW from epicenter	Sakura Chiba, Japan.	III Weak
175 km (109 mi) SW from epicenter	Kasukabe Saitama, Japan.	III Weak
180 km (112 mi) SW from epicenter	Koshigaya Saitama, Japan.	III Weak
183 km (114 mi) SW from epicenter	Matsudo Chiba, Japan.	III Weak
184 km (114 mi) SW from epicenter	Sōka Saitama, Japan.	III Weak
184 km (114 mi) SW from epicenter	Ageoshimo Saitama, Japan.	III Weak
186 km (116 mi) SSW from epicenter	Honchō Chiba, Japan.	III Weak
186 km (116 mi) SW from epicenter	Saitama Saitama, Japan.	III Weak
189 km (117 mi) SSW from epicenter	Chiba Chiba, Japan.	III Weak
192 km (119 mi) SW from epicenter	Kawaguchi Saitama, Japan.	III Weak
198 km (123 mi) SW from epicenter	Kawagoe Saitama, Japan.	III Weak
198 km (123 mi) WSW from epicenter	Maebashi Gunma, Japan.	III Weak
199 km (124 mi) SSW from epicenter	Ichihara Chiba, Japan.	III Weak
203 km (126 mi) SW from epicenter	Tokyo Tokyo, Japan.	III Weak
207 km (129 mi) WNW from epicenter	Niigata Niigata, Japan.	III Weak
216 km (134 mi) SW from epicenter	Kawasaki Kanagawa, Japan.	III Weak
228 km (142 mi) SW from epicenter	Yokohama Kanagawa, Japan.	III Weak
252 km (157 mi) NNW from epicenter	Yokote Akita, Japan.
267 km (166 mi) W from epicenter	Nagano Nagano, Japan.
279 km (173 mi) SW from epicenter	Kōfu Yamanashi, Japan.
290 km (180 mi) N from epicenter	Morioka Iwate, Japan.
297 km (185 mi) SW from epicenter	Mishima Shizuoka, Japan.

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.

Shaking reported by 35 people

People that feel an earthquake may report their experience to the US Geographic Survey. Currently, 35 people have reported shaking in 24 places, all within Japan.We keep updating this article as more ground reports become available. You may report that you felt this earthquake here.

Places with most reports:

Tokyo, Tokio, Japan: 8 people.
Sendai, Miyagi, Japan: 3 people.
Narita, Chiba, Japan: 2 people.
Iwaki, Fukushima, Japan: 2 people.
Zushi, Kanagawa, Japan: 1 person.
Higashimurayama, Tokio, Japan: 1 person.
Ōigawa, Shizuoka, Japan: 1 person.
Shimoda, Shizuoka, Japan: 1 person.
Yashio, Saitama, Japan: 1 person.
Sōka, Saitama, Japan: 1 person.

Aftershocks detected

Since this main shock, 1 smaller aftershock was detected. At a distance of 30 km (19 mi) east of this earthquake, an aftershock struck 2 days later. It measured a magnitude of 5.3

In the days before this main shock, 2 smaller foreshocks were detected. A 4.6 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 4.4	2 days earlier Mar 13, 2024 10:10 (Tokyo Time)	44 km (27 mi) ESE from Main Shock.
Foreshock	M 4.6	1 day earlier Mar 13, 2024 20:24 (Tokyo Time)	16 km (10 mi) ESE from Main Shock.
Main Shock This Earthquake	M 5.6	Mar 15, 2024 00:14 (Tokyo Time)	-
Aftershock	M 5.3	2 days later Mar 17, 2024 06:17 (Tokyo Time)	30 km (19 mi) E 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.

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 happen often in the region

Earthquakes of this strength are very common in the region. This is the strongest earthquake to hit since May 26th, 2023, when a 6.1 magnitude earthquake hit 182 km (113 mi) further south-southwest. An even stronger magnitude 7.3 earthquake struck on March 16th, 2022.

In total, 35 earthquakes with a magnitude of 5.6 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 3 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 5.6. Earthquakes of this strength are unlikely to trigger a tsunami.	This earthquake occurred at a depth of of 44 km (27 mi). Earthquakes this shallow could trigger a tsunami.

Sources

Last updated 28/04/24 04:08 (). This article contains currently available information about the earthquake and is automatically composed. We continue to update this article up to a few days after the earthquake occurred.