March 2021 Miyagi earthquake

{{About|the earthquake that happened in March 2021| the February 2021 earthquake that happened in Fukushima Prefecture|2021 Fukushima earthquake}}

{{Other uses|Miyagi earthquake (disambiguation){{!}}Miyagi earthquake}}

{{Infobox earthquake

| local-time = 18:09:45

| magnitude = 7.0 {{M|w|link=yes}} (USGS)
6.9 {{M|j|link=yes}} (JMA)

| timestamp = 2021-03-20 09:09:45

| anss-url = us7000dl6y

| isc-event = 620172298

| depth = 43.0 km (USGS)
60.0 km (JMA)

| intensity = {{MMI|VII}}

{{JMA|5+}}

| fault = Japan Trench

| image = 2021-03-20 Ishinomaki, Japan M7 earthquake shakemap (USGS).jpg

| location = {{Coord|38.475|141.607}}

| map2 = {{Location map|Japan

| lat_deg = 38

| lat_min = 28.0

| lat_sec =

| lat_dir = N

| lon_deg = 141

| lon_min = 37.6

| lon_sec =

| lon_dir = E

| label =

| label_size =

| position =

| background =

| mark = Bullseye1.svg

| marksize = 40

| width = 260

| float = center

| border =

| caption =

| relief = 1

| alt =}}

| name = March 2021 Miyagi earthquake
({{lang|ja|宮城県沖地震}})

| local-date = 20 March 2021

| tsunami =

| damage = ¥63.4 billion ($550 million USD){{Cite web|title=Significant Earthquake Database|url=https://www.ngdc.noaa.gov/hazel/view/hazards/earthquake/event-data?maxYear=2021&minYear=2021&minDamageMillionsDollars=1|author=National Geophysical Data Center / World Data Service (NGDC/WDS)|publisher=National Geophysical Data Center, NOAA|doi=10.7289/V5TD9V7K|year=2021|type=Data Set}}

| casualties = 11 injured{{cite web |title=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 |url=https://www.fdma.go.jp/disaster/info/items/20210320miyagikenokijisin6.pdf |website=Fire and Disaster Management Agency Disaster Countermeasures Headquarters |access-date=22 March 2021 |language=Japanese |date=22 March 2021}}

}}

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 {{convert|54.0|km|mi|sp=us}} to {{convert|60|km|mi|sp=us}}.{{cite web |title=M 7.0 – 27 km ENE of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us7000dl6y/executive |publisher=USGS-ANSS |access-date=20 March 2021}}{{cite web|title=Earthquake Information|url=https://www.jma.go.jp/bosai/map.html#6/39.007/140.85/&elem=int&contents=earthquake_map&lang=en|publisher=Japan Meteorological Agency|access-date=20 March 2021}} It had a maximum JMA intensity of Shindo 5+ while on the Mercalli intensity scale, it earned a rating of VII (Very strong).{{cite web |title=地震情報 |url=https://earthquake.tenki.jp/bousai/earthquake/detail/2021/03/20/2021-03-20-18-09-54.html |website=tenki.jp |access-date=22 March 2021 |language=Japanese |date=20 March 2021}} Power outages and some slight damage in Miyagi was reported.{{cite news |title=Power outages hit part of Japan's Miyagi prefecture following quake, utility says |url=https://www.reuters.com/article/japan-quake-power/power-outages-hit-part-of-japans-miyagi-prefecture-following-quake-utility-says-idUKL4N2LI05Z |access-date=20 March 2021 |agency=Reuters|date=20 March 2021}}

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.{{cite web |title=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）－ |url=https://www.jma.go.jp/jma/press/2103/20a/202103202020.html |publisher=Japan Meteorological Agency |access-date=21 March 2021}}{{cite news |title=Seismic intensity 5+ in Miyagi, M6.9 Shinkansen temporarily suspended |url=https://www.nikkei.com/article/DGXZQODG2028Q0Q1A320C2000000/ |access-date=21 March 2021 |publisher=Nikkei |date=21 March 2021 |language=Japanese}}

Earthquake

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 {{Convert|70|mm|in|abbr=on}} per year, subducting beneath Japan at the Japan Trench and dipping to the west beneath Japan. The earthquake epicenter is located {{Convert|70|km|abbr=on}} 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 {{M|j}} 7.3 earthquake struck south of the March 20 event.{{cite news |title=M7.3 Fukushima quake is aftershock of 2011 killer quake: expert |url=https://english.kyodonews.net/news/2021/02/9cee2ebaf4ad-m73-fukushima-quake-likely-aftershock-of-2011-killer-quake-expert.html |access-date=20 March 2021 |agency=Kyodo News |publisher=Kyodo News}}

=Intensity=

class="wikitable mw-collapsible" \|+Japan Meteorological Agency seismic intensity by selected location (only locations with Shindo 5 Lower and higher are shown) !Intensity !Prefecture !Location
style="background:#FF8C00" \|5+ \|Miyagi \|Higashi-matsushima, Ishinomaki, Iwanuma, Matsushima, Misato, Osaki, Sendai, Tome, Wakuya, Zaō
rowspan="3" style="background:#FFD700; color:#000000" \|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

class="wikitable mw-collapsible"

|+Japan Meteorological Agency seismic intensity by selected location (only locations with Shindo 5 Lower and higher are shown)

!Intensity

!Prefecture

!Location

style="background:#FF8C00" |5+

|Miyagi

|Higashi-matsushima, Ishinomaki, Iwanuma, Matsushima, Misato, Osaki, Sendai, Tome, Wakuya, Zaō

rowspan="3" style="background:#FFD700; color:#000000" |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

class="wikitable mw-collapsible"

|+2021 Miyagi earthquake aftershocks

!Time (UTC)

!Location

!Magnitude

!Depth (km)

!MMI

!Ref.

style="background:#a50021; color:#fff"

|2021-03-20 09:09:44

|29 km east northeast of Ishinomaki

|7.0

|43.0

|VII

2021-03-20 09:34:58

|47 km east southeast of Ishinomaki

|4.6

|61.1

| -

|{{cite web |title=M 4.6 – 47 km ESE of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us6000dwsl/executive |publisher=United States Geological Survey |access-date=18 April 2021}}

2021-03-20 16:41:17

|49 km east southeast of Ishinomaki

|4.3

|61.4

| -

|{{cite web |title=M 4.3 – 49 km ESE of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us7000dl9f/executive |publisher=United States Geological Survey |access-date=18 April 2021}}

2021-04-03 12:58:27

|30 km east southeast of Ōfunato

|4.6

|41.2

| -

|{{cite web |title=M 4.6 – 30 km ESE of Ōfunato, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us6000dyr6/executive |publisher=United States Geological Survey |access-date=18 April 2021}}

2021-04-06 20:10:36

|79 km east southeast of Ishinomaki

|4.2

|45.1

| -

|{{cite web |title=M 4.2 – 79 km ESE of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us6000dzhz/executive |publisher=United States Geological Survey |access-date=18 April 2021}}

2021-04-14 10:02:52

|112 km east southeast of Ishinomaki

|4.3

|39.6

| -

|{{cite web |title=M 4.3 – 112 km ESE of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us6000e1fu/executive |publisher=United States Geological Survey |access-date=18 April 2021}}

2021-04-16 11:51:36

|77 km east of Ishinomaki

|4.5

|35.0

| -

|{{cite web |title=M 4.5 – 77 km E of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us6000e21g/executive |publisher=United States Geological Survey |access-date=18 April 2021}}

style="background:#FA8072; color:#000000"

|2021-04-18 00:29:12

|Near the east coast of Honshu

|5.6

|51.7

|IV

|{{cite web |title=M 5.6 – near the east coast of Honshu, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us6000e2hf/executive |publisher=United States Geological Survey |access-date=18 April 2021}}

style="background:#FA8072; color:#000000"

|2021-04-18 00:29:25

|49 km east southeast of Ishinomaki

|5.6

|31.3

|IV

|{{cite web |title=M 5.6 – 49 km ESE of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us6000e2hq/executive |publisher=United States Geological Survey |access-date=18 April 2021}}

2021-04-19 04:06:21

|42 km south southeast of Ishinomaki

|4.9

|55.1

| -

|{{cite web |title=M 4.9 – 42 km SSE of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us6000e2sm/executive |publisher=United States Geological Survey |access-date=19 April 2021}}

Impact

The earthquake caused 11 minor injuries in the prefectures of Iwate, Miyagi and Fukushima.{{Cite web|url=https://abcnews.go.com/International/wireStory/strong-earthquake-shakes-japans-capital-usgs-72-76575287|title=Strong quake shakes Japan; minor injuries, no major damage|author=Mari Yamaguchi|publisher=ABC News|location=United States|date=March 20, 2021|access-date=March 20, 2021}} 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.{{cite news |title=宮城で震度5強で計8人けが 1週間程度地震注意 |url=https://news.tv-asahi.co.jp/news_society/articles/000210512.html |access-date=21 March 2021 |agency=All Nippon News |publisher=All Nippon News |date=21 March 2021 |archive-date=21 March 2021 |archive-url=https://web.archive.org/web/20210321070105/https://news.tv-asahi.co.jp/news_society/articles/000210512.html |url-status=dead }} Two elderly women aged 90 and 70 sustained minor head and shoulder injuries respectively when they were struck by furniture in Iwanuma, Miyagi. There was one injury each reported in Date, Ishinomaki, Kesennuma and Tōno.

Power outages were reported in some parts of Tohoku, forcing the suspension of bullet train services by the East Japan Railway Company.{{Cite web|url=https://www.nbcnews.com/news/world/tsunami-advisory-issued-after-magnitude-7-2-earthquake-strikes-japan-n1261655|title=Tsunami advisory issued after earthquake strikes off Japan's coast|author=Adela Suliman, Arata Yamamoto|publisher=NBC News|date=March 20, 2021|access-date=March 20, 2021}} In Shiogama, a {{Convert|6|m|adj=on|sp=us|spell=in}} wall supporting an inclined surface breached and collapsed during the earthquake.

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.{{cite news |title=Magnitude 7.2 earthquake strikes off northeast Japan, tsunami advisory issued: JMA |url=https://english.alarabiya.net/News/world/2021/03/20/Magnitude-7-2-earthquake-strikes-off-northeast-Japan-tsunami-advisory-issued-JMA |access-date=21 March 2021 |work=Al Arabiya |agency=Reuters|date=20 March 2021}} No radiation anomalies or changes in cooling water levels were detected at the power plant.{{cite web |author1=Tokyo Electric Power Company Holdings, Inc |title=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） |url=https://www.tepco.co.jp/press/mail/2021/1586625_9004.html |website=TEPCO |access-date=22 March 2021 |language=Japanese |date=20 March 2021}}

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.{{cite web | url=https://www.f4wonline.com/news/new-japan/earthquake-temporarily-halts-njpw-cup-event-sendai-336421 | title=Earthquake temporarily halts NJPW Cup event in Sendai | date=20 March 2021 }}

=Tsunami warning=

Following the earthquake, a tsunami advisory was issued at 18:11 JST for Miyagi Prefecture for waves of up to {{Convert|1|m|sp=us}}.{{Cite web|title=気象庁｜統合地図ページ|url=https://www.jma.go.jp/bosai/map.html#8/39.077/141.603/&elem=warn&contents=tsunami&lang=en|access-date=2021-03-20|publisher=Japan Meteorological Agency}} Despite the warnings, no tsunamis were observed; this is because the earthquake had ruptured a deeper portion of the subduction zone.{{cite news |title=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 |url=https://www.jiji.com/jc/article?k=2021032000447&g=soc |access-date=22 March 2021 |agency=Jiji |publisher=Jiji |date=20 March 2021}}{{Cite web|date=2021-03-20|title=Magnitude 7.2 quake rocks northeastern Japan|url=https://www.japantimes.co.jp/news/2021/03/20/national/miyagi-earthquake-japan/|access-date=2021-03-20|website=The Japan Times|language=en-US|archive-date=20 March 2021|archive-url=https://web.archive.org/web/20210320223414/https://www.japantimes.co.jp/news/2021/03/20/national/miyagi-earthquake-japan/|url-status=dead}} The tsunami advisory was then withdrawn at around 19:30 JST.{{cite news |title=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 |url=https://www3.nhk.or.jp/news/html/20210320/k10012926531000.html |access-date=21 March 2021 |agency=NHK |publisher=NHK |date=20 March 2021}}

Other events

On May 1, at 10:27 local time, a {{M|w}} 6.9 or {{M|j}} 6.6 earthquake struck the southern tip of the Oshika Peninsula.{{cite web |title=M 6.9 – 38 km ESE of Ishinomaki, Japan |url=https://earthquake.usgs.gov/earthquakes/eventpage/us7000dz5t/executive |publisher=United States Geological Survey |access-date=2 May 2021 |date=1 May 2021}} The earthquake had a depth of 47.3 km or 66 km and a maximum intensity of VI (Strong) or Shindo 5 upper.{{cite web |title=Issued at 10:35 JST 01 May 2021 Earthquake and Seismic Intensity Information part 2 |url=https://www.jma.go.jp/bosai/map.html#6/38.823/142.434/&elem=hypo&contents=earthquake_map&lang=en |publisher=Japan Meteorological Agency |access-date=2 May 2021 |date=1 May 2021}} 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.{{cite news |author1=Rei Yamagishi |title=｢1週間程度、強い地震警戒」気象庁、宮城の地震受け |url=https://www.asahi.com/articles/ASP515T7VP51UTIL00N.html |access-date=2 May 2021 |publisher=Asahi Shimbun Digital |date=1 May 2021}} 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.{{cite news |author1=Ryo Yamagishi |title=JMA will stop calling temblors an aftershock of 3/11 quake |url=http://www.asahi.com/ajw/articles/14322973 |access-date=2 May 2021 |agency=The Asahi Shimbun |date=1 April 2021}} The agency also could not determine if this event was related to the earthquake of March 20.

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.{{cite news |title=地震でけが計3人に宮城や福島で |url=https://www3.nhk.or.jp/news/html/20210501/k10013008141000.html |access-date=2 May 2021 |agency=NHK |date=1 May 2021 |language=Japanese}} A third individual from Soma City in Fukushima Prefecture fell while shopping at a supermarket and was taken to a hospital for treatment.

References

External links

[https://www.jma.go.jp/bosai/map.html#6/38.954/143.914/&elem=hypo&contents=earthquake_map&lang=en Japan Meteorological Agency (JMA) earthquake information]

Category:2021 earthquakes

Category:Earthquakes in Miyagi Prefecture

Category:Earthquakes of the Reiwa era

Category:March 2021 in Japan

Category:Tōhoku region

Category:2021 earthquakes in Asia

Category:2021 disasters in Japan