March 2021 Miyagi earthquake

This article is about the earthquake that happened in March 2021. For the February 2021 earthquake that happened in Fukushima Prefecture, see 2021 Fukushima earthquake.

For other uses, see Miyagi earthquake.

Earthquakes in Japan

March 2021 Miyagi earthquake
(宮城県沖地震)

UTC time| 2021-03-20 09:09:45
ISC event| 620172298
USGS-ANSS| ComCat
Local date| 20 March 2021
Local time| 18:09:45
Magnitude| 7.0 Mw (USGS)
6.9 MJMA (JMA)
Depth| 43.0 km (USGS)
60.0 km (JMA)
Epicenter| 38°28′30″N 141°36′25″E﻿ / ﻿38.475°N 141.607°E﻿ / 38.475; 141.607
Fault| Japan Trench
Total damage| ¥63.4 billion ($550 million USD)[1]
Max. intensity| VII (Very strong)

JMA 5+
Casualties| 11 injured[2]

On March 20, 2021 at 18:09 JST (09:09 UTC). The magnitude 6.9 or 7.0 earthquake struck offshore east of Tōhoku, Japan at a depth of 54.0 kilometers (33.6 mi) to 60 kilometers (37 mi).[3][4] It had a maximum JMA intensity of Shindo 5+ while on the Mercalli intensity scale, it earned a rating of VII (Very strong).[5] Power outages and some slight damage in Miyagi was reported.[6]

A press release by the Japan Meteorological Agency stated that the earthquake was an aftershock of the 2011 Tōhoku earthquake and tsunami from ten years prior.[7][8]

## Earthquake[edit]

The earthquake occurred as the result of thrust faulting near the subduction zone interface plate boundary between the Pacific and North America plates. Moment tensor solutions indicate that slip occurred either on a moderately dipping fault striking to the south, or a moderately dipping fault striking to the north-northeast, consistent with the east-west oriented compression expected in this region. At the location of this earthquake, the Pacific plate moves approximately westward relative to the North American plate at a velocity of 70 mm (2.8 in) per year, subducting beneath Japan at the Japan Trench and dipping to the west beneath Japan. The earthquake epicenter is located 70 km (43 mi) west of the epicenter of the March 2011 earthquake. It came just nine days after the tenth anniversary of the March 11, 2011 disaster, and just over a month since a MJMA 7.3 earthquake struck south of the March 20 event.[9]

### Intensity[edit]

Japan Meteorological Agency seismic intensity by selected location (only locations with Shindo 5 Lower and higher are shown)[4][5] Intensity | Prefecture  | Location

|
|

5+  | Miyagi | Higashi-matsushima, Ishinomaki, Iwanuma, Matsushima, Misato, Osaki, Sendai, Tome, Wakuya, Zaō
5−  | Miyagi  | Kakuda, Kawasaki, Kesennuma, Kurihara, Marumori, Minami, Natori, Ogawara, Ohira, Osata, Rifu, Sendai, Shibata, Watari, Yamomoto
Iwate | Ichinoseki, Ofunato, Sumita
Fukushima | Futaba, Iitate, Kunimi, Minami, Namie, Okuma, Shinchi, Soma, Tamura

## Aftershocks[edit]

2021 Miyagi earthquake aftershocks  Time (UTC)  | Location  | Magnitude  | Depth (km)  | MMI  | Ref.

|
|
|
|
|

2021-03-20 09:09:44  | 29 km east northeast of Ishinomaki  | 7.0  | 43.0  | VII  | [3]
2021-03-20 09:34:58  | 47 km east southeast of Ishinomaki  | 4.6  | 61.1  | \-  | [10]
2021-03-20 16:41:17  | 49 km east southeast of Ishinomaki  | 4.3  | 61.4  | \-  | [11]
2021-04-03 12:58:27  | 30 km east southeast of Ōfunato  | 4.6  | 41.2  | \-  | [12]
2021-04-06 20:10:36  | 79 km east southeast of Ishinomaki  | 4.2  | 45.1  | \-  | [13]
2021-04-14 10:02:52  | 112 km east southeast of Ishinomaki  | 4.3  | 39.6  | \-  | [14]
2021-04-16 11:51:36  | 77 km east of Ishinomaki  | 4.5  | 35.0  | \-  | [15]
2021-04-18 00:29:12  | Near the east coast of Honshu  | 5.6  | 51.7  | IV  | [16]
2021-04-18 00:29:25  | 49 km east southeast of Ishinomaki  | 5.6  | 31.3  | IV  | [17]
2021-04-19 04:06:21  | 42 km south southeast of Ishinomaki  | 4.9  | 55.1  | \-  | [18]

## Impact[edit]

The earthquake caused 11 minor injuries in the prefectures of Iwate, Miyagi and Fukushima[19] Many of the injured were from Miyagi Prefecture. Four individuals from Sendai, Miyagi endured slight injuries. In Morioka, Iwate, a woman fell and suffered cuts.[20] Two elderly women aged 90 and 70 sustained minor head and shoulder injuries respectively when they were struck by furniture in Iwanuma, Miyagi.[21] There was one injury each reported in Date, Ishinomaki, Kesennuma and Tōno.[2]

Power outages were reported in some parts of Tohoku, forcing the suspension of bullet train services by the East Japan Railway Company.[22] In Shiogama, a six-meter (20 ft) wall supporting an inclined surface breached and collapsed during the earthquake.[20]

As a precaution, authorities from the Tohoku Electric Power utility shut down the Onagawa Nuclear Power Plant whilst the Tokyo Electric Power Company checked the conditions at the Fukushima Daiichi Nuclear Power Plant.[23] No radiation anomalies or changes in cooling water levels were detected at the power plant.[24]

A New Japan Pro Wrestling event in Sendai was temporarily halted mid-match due to the earthquake, which was captured by cameras recording the show. The event resumed approximately half an hour later after safety checks were carried out.[25]

### Tsunami warning[edit]

Following the earthquake, a tsunami advisory was issued at 18:11 JST for Miyagi Prefecture for waves of up to 1 meter (3 ft 3 in).[26] Despite the warnings, no tsunamis were observed; this is because the earthquake had ruptured a deeper portion of the subduction zone.[21][27] The tsunami advisory was then withdrawn at around 19:30 JST.[28]

## Other events[edit]

On May 1, at 10:27 local time, a Mw 6.9 or MJMA 6.6 earthquake struck the southern tip of the Oshika Peninsula.[29] The earthquake had a depth of 47.3 km or 66 km and a maximum intensity of VI (Strong) or Shindo 5 upper.[30] According to the Japan Meteorological Survey, the earthquake would not be considered an aftershock of the 2011 Great East Japan earthquake as such announcements had ceased as of April 1 of 2021.[31] This is due to the decreasing rate of earthquakes which made it harder to determine if events like those of May 1 were actual aftershocks.[32] The agency also could not determine if this event was related to the earthquake of March 20.[33]

Minor damage including broken windows and a water pipe rupture was reported. The earthquake resulted in the suspension of Shinkansen services in the Tohoku region. In addition, three people sustained minor injuries. Two of the victims were using a hot spring at Onagawa Station when the quake struck and shattered window panels.[33] A third individual from Soma City in Fukushima Prefecture fell while shopping at a supermarket and was taken to a hospital for treatment.[33]

## See also[edit]

* Earth sciences portal
* Japan portal

* List of earthquakes in 2021
* List of earthquakes in Japan
* 2021 Fukushima earthquake
* April 2011 Miyagi earthquake
* 2012 Kamaishi earthquake

## References[edit]

1. ^ National Geophysical Data Center / World Data Service (NGDC/WDS) (2021). "Significant Earthquake Database" (Data Set). National Geophysical Data Center, NOAA. doi:10.7289/V5TD9V7K.
2. ^ a b "宮城県沖を震源とする地震による被害及び 消防機関等の対応状況（第６報" (PDF). Fire and Disaster Management Agency Disaster Countermeasures Headquarters (in Japanese). 22 March 2021. Retrieved 22 March 2021.
3. ^ a b "M 7.0 - 27 km ENE of Ishinomaki, Japan". USGS-ANSS. USGS. Retrieved 20 March 2021.
4. ^ a b "Earthquake Information". Japan Meteorological Agency. JMA. Retrieved 20 March 2021.
5. ^ a b "地震情報". tenki.jp (in Japanese). 20 March 2021. Retrieved 22 March 2021.
6. ^ "Power outages hit part of Japan's Miyagi prefecture following quake, utility says". Reuters. 20 March 2021. Retrieved 20 March 2021.
7. ^ "令和３年３月20日18時09分頃の宮城県沖の地震について －「平成23年（2011年）東北地方太平洋沖地震」について（第91報）－". Japan Meteorological Agency. Retrieved 21 March 2021.
8. ^ "Seismic intensity 5+ in Miyagi, M6.9 Shinkansen temporarily suspended" (in Japanese). Nikkei. 21 March 2021. Retrieved 21 March 2021.
9. ^ "M7.3 Fukushima quake is aftershock of 2011 killer quake: expert". Kyodo News. Kyodo News. Retrieved 20 March 2021.
10. ^ "M 4.6 - 47 km ESE of Ishinomaki, Japan". earthquake.usgs.gov. USGS. Retrieved 18 April 2021.
11. ^ "M 4.3 - 49 km ESE of Ishinomaki, Japan". earthquake.usgs.gov. USGS. Retrieved 18 April 2021.
12. ^ "M 4.6 - 30 km ESE of Ōfunato, Japan". earthquake.usgs.gov. USGS. Retrieved 18 April 2021.
13. ^ "M 4.2 - 79 km ESE of Ishinomaki, Japan". earthquake.usgs.gov. USGS. Retrieved 18 April 2021.
14. ^ "M 4.3 - 112 km ESE of Ishinomaki, Japan". earthquake.usgs.gov. USGS. Retrieved 18 April 2021.
15. ^ "M 4.5 - 77 km E of Ishinomaki, Japan". earthquake.usgs.gov. USGS. Retrieved 18 April 2021.
16. ^ "M 5.6 - near the east coast of Honshu, Japan". earthquake.usgs.gov. USGS. Retrieved 18 April 2021.
17. ^ "M 5.6 - 49 km ESE of Ishinomaki, Japan". earthquake.usgs.gov. USGS. Retrieved 18 April 2021.
18. ^ "M 4.9 - 42 km SSE of Ishinomaki, Japan". earthquake.usgs.gov. USGS. Retrieved 19 April 2021.
19. ^ Mari Yamaguchi (20 March 2021). "Strong quake shakes Japan; minor injuries, no major damage". ABC News. Retrieved 20 March 2021.
20. ^ a b "宮城で震度5強で計8人けが 1週間程度地震注意". All Nippon News. All Nippon News. 21 March 2021. Archived from the original on 21 March 2021. Retrieved 21 March 2021.
21. ^ a b "宮城で震度５強 一時津波注意報、複数けが人―東日本大震災の余震・気象庁". Jiji. Jiji. 20 March 2021. Retrieved 22 March 2021.
22. ^ Adela Suliman, Arata Yamamoto (20 March 2021). "Tsunami advisory issued after earthquake strikes off Japan's coast". NBC News. Retrieved 20 March 2021.
23. ^ "Magnitude 7.2 earthquake strikes off northeast Japan, tsunami advisory issued: JMA". Al Arabiya. Reuters. 20 March 2021. Retrieved 21 March 2021.
24. ^ Tokyo Electric Power Company Holdings, Inc (20 March 2021). "2021年3月20日地震情報（福島第一原子力発電所・福島第二原子力発電所関連）". TEPCO (in Japanese). Retrieved 22 March 2021.
25. ^ https://www.f4wonline.com/news/new-japan/earthquake-temporarily-halts-njpw-cup-event-sendai-336421
26. ^ "気象庁｜統合地図ページ". www.jma.go.jp. Retrieved 20 March 2021.
27. ^ "Magnitude 7.2 quake rocks northeastern Japan". The Japan Times. 20 March 2021. Archived from the original on 20 March 2021. Retrieved 20 March 2021.
28. ^ "宮城県で震度5強 今後1週間程度は最大震度5強程度の地震に注意". NHK. NHK. 20 March 2021. Retrieved 21 March 2021.
29. ^ "M 6.9 - 38 km ESE of Ishinomaki, Japan". earthquake.usgs.gov. USGS. 1 May 2021. Retrieved 2 May 2021.
30. ^ "Issued at 10:35 JST 01 May 2021 Earthquake and Seismic Intensity Information part 2". Japan Meteorological Agency. 1 May 2021. Retrieved 2 May 2021.
31. ^ Rei Yamagishi (1 May 2021). "｢1週間程度、強い地震警戒」 気象庁、宮城の地震受け". Asahi Shimbun Digital. Retrieved 2 May 2021.
32. ^ Ryo Yamagishi (1 April 2021). "JMA will stop calling temblors an aftershock of 3/11 quake". The Asahi Shimbun. Retrieved 2 May 2021.
33. ^ a b c "地震でけが 計3人に 宮城や福島で" (in Japanese). NHK. 1 May 2021. Retrieved 2 May 2021.

## External links[edit]

Wikimedia Commons has media related to March 2021 Miyagi earthquake.

* Japan Meteorological Agency (JMA) earthquake information

* v
* t
* e

← Earthquakes in 2021 →

January|

* Khövsgöl, Mongolia (6.7, Jan 11)
* West Sulawesi, Indonesia (6.2, Jan 14) †

February|

* Mindanao, Philippines (6.0, Feb 7)
* Loyalty Islands, France (7.7, Feb 10)
* Fukushima, Japan (7.1, Feb 13)
* Sisakht, Iran (5.4, Feb 17)

March|

* Larissa, Greece (6.3, Mar 3)
* Kermadec Islands, New Zealand (7.4 & 8.1, Mar 4)
* Miyagi, Japan (7.0, Mar 20)

April|

* East Java, Indonesia (6.0, Apr 10)
* Assam, India (6.0, Apr 28)

May|

* Yunnan, China (6.1, May 21)
* Qinghai, China (7.3, May 21)

June|

* Mala, Peru (5.8, June 23)

July|

* Rasht, Tajikistan (5.7, July 10)
* Chignik, Alaska (8.2, July 29)

August|

* Davao Oriental, Philippines (7.1, Aug 12)
* South Sandwich Islands (7.5 & 8.1, Aug 12)
* Nippes, Haiti (7.2, Aug 14) † ‡

September|

* Guerrero, Mexico (7.0, Sep 7)
* Sichuan, China (5.4, Sep 15)
* Melbourne, Australia (5.9, Sep 21)
* Arkalochori, Greece (6.0, Sep 27)

October|

* Balochistan, Pakistan (5.9, Oct 6)
* Chiba, Japan (5.9, Oct 7)
* Lasithi, Greece (6.4, Oct 12)
* Bali, Indonesia (4.7, Oct 15)

November|

* Hormozgan, Iran (6.0 & 6.3, Nov 6)
* Loreto, Peru (7.5, Nov 28)

December|

* Flores, Indonesia (7.3, Dec 14)

* † indicates earthquake resulting in at least 30 deaths
* ‡ indicates the deadliest earthquake of the year
* Dates for all earthquakes are in UTC

* v
* t
* e

Earthquakes in Japan

Historical|

* 684 Hakuho
* 869 Jōgan
* 1293 Kamakura
* 1361 Shōhei
* 1498 Meiō
* 1586 Tenshō
* 1596 Fushimi
* 1605 Keichō
* 1611 Aizu
* 1611 Sanriku
* 1662 Kanbun
* 1662 Hyūga-nada
* 1677 Bōsō
* 1703 Genroku
* 1707 Hōei
* 1741 Kampo
* 1751 Takada
* 1771 Great Yaeyama
* 1792 Unzen
* 1804 Kisakata
* 1828 Sanjō
* 1833 Shōnai
* 1847 Zenkoji
* 1854 Iga–Ueno
* 1854 Nankai
* 1854 Tōkai
* 1855 Edo
* 1858 Hietsu
* 1872 Hamada
* 1889 Kumamoto
* 1891 Mino–Owari
* 1894 Tokyo
* 1894 Shōnai
* 1896 Sanriku
* 1896 Rikuu

20th century|

* 1911 Kikai Island
* 1914 Senboku
* 1922 Shimabara
* 1923 Great Kantō
* 1925 North Tajima
* 1927 North Tango
* 1930 North Izu
* 1933 Sanriku
* 1936 Miyagi
* 1939 Oga
* 1940 Shakotan
* 1941 Hyūga-nada
* 1943 Tottori
* 1944 Tōnankai
* 1945 Mikawa
* 1946 Nankai
* 1948 Fukui
* 1952 Tokachi
* 1961 North Mino
* 1963 Kuril Islands
* 1964 Niigata
* 1968 Ebino
* 1968 Hyūga-nada
* 1968 Tokachi
* 1973 Nemuro Peninsula
* 1974 Izu Peninsula
* 1978 Izu Ōshima
* 1978 Miyagi
* 1982 Urakawa
* 1983 Sea of Japan
* 1984 Nagano
* 1993 Kushiro
* 1993 Okushiri
* 1994 offshore Sanriku
* 1995 Hanshin
* 2000 Tottori

21st century|

* 2001 Geiyo
* 2003 Miyagi
* 2003 Tokachi
* 2004 Chūetsu
* 2005 Fukuoka
* 2005 Miyagi
* 2006 Kuril Islands
* 2007 Chūetsu
* 2007 Kuril Islands
* 2007 Noto
* 2008 Iwate–Miyagi
* 2008 Iwate
* 2009 Shizuoka
* 2011 Tōhoku
* 2011 Nagano
* 2011 Shizuoka
* 2011 Miyagi
* 2011 Fukushima
* 2012 Chiba
* 2012 Sanriku
* 2014 Nagano
* 2015 Ogasawara
* 2016 Kumamoto
* 2016 Tottori
* 2016 Fukushima
* 2018 Osaka
* 2018 Hokkaido Eastern Iburi
* 2019 Yamagata
* 2021 Fukushima
* 2021 Miyagi
* 2021 Chiba
* 2022 Fukushima
* 2023 Noto
* 2024 Noto

Related articles|

* Tōkai earthquakes
* Nankai megathrust earthquakes
* Kantō earthquakes
* South Kantō earthquakes
* Matsushiro earthquake swarm
* Noto earthquake swarm

* v
* t
* e

2011 Tōhoku earthquake and tsunami

Nuclear
accidents|

| Power plants|

* Fukushima Daiichi nuclear disaster
* Unit 1
* Unit 2
* Unit 3
* Units 4-6
* Fukushima Daini plant
* Tōkai plant
* Onagawa plant
* Higashidori plant
* Rokkasho plant

|

Sequence of events|

* Timeline
* reactions
* International
* Japanese
* Radiation effects
* Leaks and dumping of radioactive water
* Aftermath

Topics|

* Okawa School tsunami tragedy
* Casualties
* Cleanup
* Fukushima 50
* Towns damaged
* Investigation
* National Diet
* Government
* Comparison
* Accident Rating

Movements|

* Project Sunshine for Japan
* Safecast (organization)
* Sayonara Nuclear Power Plants

Foreshocks,
Aftershocks|

* Sanriku, Japan (7.3, 9 March 2011)
* Miyagi, Japan (7.1, 7 April 2011)
* Fukushima, Japan (6.6, 11 April 2011)
* Miyagi, Japan (7.3, 7 December 2012)
* Fukushima, Japan (6.9, 22 November 2016)
* Fukushima, Japan (7.1, 13 February 2021)
* Miyagi, Japan (7.0, 20 March 2021)

Relief and
Recovery|

| Efforts|

* Humanitarian response
* Operation Pacific Assist
* Operation Tomodachi
* Reconstruction Agency
* Yuzuru Hanyu Notte Stellata

|

Fundraisers|

* Wrestling in Japan
* Hong Kong
* Taiwan

Pop culture|

* Films
* Documentaries
* Songs
* Manga
* Books
* TV drama

Other|

* Impact on video game industry
* No.18 Kyotoku-maru
* Tsunami fish
* Japan Trench Fast Drilling Project
* Ryou-Un Maru
* 869 Sanriku earthquake
* 2011 local elections
* Miracle Pine Tree
* Shinkansen Relay

* See also:  Japanese earthquakes
* Seismicity of the Sanriku coast
* List of tsunamis
* Nuclear power in Japan, section Seismicity
* Nuclear and radioactive incidents

*[Max.]: Maximum
*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template