Shallow M6.1 Earthquake struck on Thursday Afternoon 45mi from Japan.

Written by Earthquakelist.org on April 4th, 2024. Last updated May 1st, 2024.

A shallow and strong Magnitude 6.1 earthquake struck 45 miles from Japan around noon of Thursday April 4th, 2024. Roughly 12 million people may have felt this earthquake.

Earthquake Summary

This earthquake struck 45 miles (72 km) from Japan The center of this earthquake had a quite shallow depth of 29 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	Apr 4, 2024 12:16 (Tokyo Time) - Apr 4, 2024 03:16 Universal Time.
Location:	107 km SE of Sendai, Miyagi, Japan. Coordinates 37°42'37"N 141°51'22"E.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 6.1 Detected by 45 stations. Maximum Error Range ±0.046 .
Depth:	29 km (18 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 12 million people exposed to shaking

An estimated 12 million have been exposed to shaking (An MMI or Modified Mercalli Intensity level II or higher) as a result of this earthquake according scientific estimates published by the USGS.

An estimated 4,229,000 people were exposed to level IV. At this level, light shaking and likely no damage can be expected. Intensity level III was experienced by the majority of people (around 8 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
0	II	Very weak	None
8,214,000	III	Weak	Probably none
4,229,000	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 . Located 80 kilometer (50 mi) east-northeast of the epicenter of this earthquake, Namie (Fukushima, Japan) is the nearest significant population center. Namie experienced an earthquake intensity (MMI Scale) of roughly IV. That level implies light shaking and likely no damage.

Multiple major population centers exist within 300km of the earthquake that struck today. Tokyo is located 296 km to the southwest (intensity unknown, possibly low). Yokohama is located 321 km to the southwest (intensity unknown, possibly low). Sendai is located 107 km to the northwest and experienced an intensity of IV (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)
80 km (50 mi) WSW from epicenter	Namie Fukushima, Japan.	IV Light
92 km (57 mi) NNW from epicenter	Ishinomaki Miyagi, Japan.	IV Light
95 km (59 mi) WNW from epicenter	Watari Miyagi, Japan.	IV Light
97 km (60 mi) NW from epicenter	Yamoto Miyagi, Japan.	IV Light
98 km (61 mi) WNW from epicenter	Iwanuma Miyagi, Japan.	IV Light
99 km (62 mi) NW from epicenter	Shiogama Miyagi, Japan.	IV Light
100 km (62 mi) WNW from epicenter	Kakuda Miyagi, Japan.	IV Light
103 km (64 mi) NW from epicenter	Rifu Miyagi, Japan.	IV Light
105 km (65 mi) WNW from epicenter	Ōkawara Miyagi, Japan.	IV Light
107 km (66 mi) NW from epicenter	Sendai Miyagi, Japan.	IV Light
113 km (70 mi) WNW from epicenter	Shiroishi Miyagi, Japan.	IV Light
113 km (70 mi) SW from epicenter	Iwaki Fukushima, Japan.	IV Light
114 km (71 mi) NW from epicenter	Tomiya Miyagi, Japan.	IV Light
115 km (71 mi) W from epicenter	Hobaramachi Fukushima, Japan.	IV Light
116 km (72 mi) WSW from epicenter	Funehikimachi-funehiki Fukushima, Japan.	IV Light
122 km (76 mi) W from epicenter	Fukushima Fukushima, Japan.	IV Light
124 km (77 mi) NW from epicenter	Furukawa Miyagi, Japan.	IV Light
126 km (78 mi) W from epicenter	Nihommatsu Fukushima, Japan.	IV Light
134 km (83 mi) WSW from epicenter	Kōriyama Fukushima, Japan.	IV Light
138 km (86 mi) WSW from epicenter	Sukagawa Fukushima, Japan.	IV Light
142 km (88 mi) SW from epicenter	Kitaibaraki Ibaraki, Japan.	IV Light
143 km (89 mi) WNW from epicenter	Yamagata Yamagata, Japan.	IV Light
148 km (92 mi) NNW from epicenter	Ichinoseki Iwate, Japan.	IV Light
149 km (93 mi) WNW from epicenter	Tendō Yamagata, Japan.	IV Light
151 km (94 mi) WNW from epicenter	Higashine Yamagata, Japan.	IV Light
154 km (96 mi) W from epicenter	Yonezawa Yamagata, Japan.	IV Light
157 km (98 mi) WNW from epicenter	Sagae Yamagata, Japan.	III Weak
163 km (101 mi) SW from epicenter	Hitachi Ibaraki, Japan.	III Weak
170 km (106 mi) NNW from epicenter	Mizusawa Iwate, Japan.	III Weak
178 km (111 mi) WSW from epicenter	Nasushiobara Tochigi, Japan.	III Weak
180 km (112 mi) WSW from epicenter	Kuroiso Tochigi, Japan.	III Weak
186 km (116 mi) NNW from epicenter	Kitakami Iwate, Japan.	III Weak
187 km (116 mi) SW from epicenter	Hitachi-Naka Ibaraki, Japan.	III Weak
189 km (117 mi) SW from epicenter	Katsuta Ibaraki, Japan.	III Weak
196 km (122 mi) SW from epicenter	Mito Ibaraki, Japan.	III Weak
197 km (122 mi) NNW from epicenter	Hanamaki Iwate, Japan.	III Weak
216 km (134 mi) SW from epicenter	Utsunomiya Tochigi, Japan.	III Weak
230 km (143 mi) NNW from epicenter	Morioka Iwate, Japan.
251 km (156 mi) W from epicenter	Niigata Niigata, Japan.
265 km (165 mi) SW from epicenter	Kashiwa Chiba, Japan.
269 km (167 mi) NW from epicenter	Akita Akita, Japan.
274 km (170 mi) SW from epicenter	Koshigaya Saitama, Japan.	III Weak
276 km (171 mi) SW from epicenter	Matsudo Chiba, Japan.
279 km (173 mi) SW from epicenter	Honchō Chiba, Japan.
280 km (174 mi) SW from epicenter	Saitama Saitama, Japan.	III Weak
281 km (175 mi) SSW from epicenter	Chiba Chiba, Japan.
285 km (177 mi) SW from epicenter	Kawaguchi Saitama, Japan.
286 km (178 mi) WSW from epicenter	Maebashi Gunma, Japan.
291 km (181 mi) SW from epicenter	Kawagoe Saitama, Japan.
296 km (184 mi) SW from epicenter	Tokyo Tokyo, Japan.
309 km (192 mi) SW from epicenter	Kawasaki Kanagawa, Japan.
312 km (194 mi) N from epicenter	Hachinohe Aomori, Japan.
321 km (199 mi) SW from epicenter	Yokohama Kanagawa, Japan.
346 km (215 mi) WSW from epicenter	Nagano Nagano, Japan.
371 km (231 mi) SW from epicenter	Kōfu Yamanashi, Japan.
395 km (245 mi) SW from epicenter	Numazu Shizuoka, Japan.
400 km (249 mi) WSW from epicenter	Kurobe-shi Toyama, 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 31 people

People that feel an earthquake may report their experience to the US Geographic Survey. Currently, 31 people have reported shaking in 18 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: 13 people.
Sendai, Miyagi, Japan: 2 people.
Sagamihara, Kanagawa, Japan: 1 person.
Komae, Tokio, Japan: 1 person.
Inagi, Tokio, Japan: 1 person.
Higashimurayama, Tokio, Japan: 1 person.
Sōka, Saitama, Japan: 1 person.
Yokosuka, Kanagawa, Japan: 1 person.
Aomori, Aomori, Japan: 1 person.
Hirosaki, Aomori, Japan: 1 person.

2 Aftershocks detected

This main shock was followed by 2 smaller aftershocks. At a distance of 62 km (38 mi) north-northwest of this earthquake, an aftershock struck 2 days later. It measured a magnitude of 4.4

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 6.1	Apr 4, 2024 12:16 (Tokyo Time)	-
Aftershock	M 3.9	2 days later Apr 6, 2024 00:40 (Tokyo Time)	95 km (59 mi) SW from Main Shock.
Aftershock	M 4.4	2 days later Apr 6, 2024 15:13 (Tokyo Time)	62 km (38 mi) NNW 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.

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 March 16th, 2022, when a 7.3 magnitude earthquake hit 24 km (15 mi) further west. That was also the heaviest earthquake to hit the region in the past 10 years.

In total, 13 earthquakes with a magnitude of 6.1 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 9 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 6.1. Earthquakes of this strength are unlikely to trigger a tsunami.	This earthquake occurred at a depth of of 29 km (18 mi). Earthquakes this shallow could trigger a tsunami.

Sources

Last updated 01/05/24 01:38 (). 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.