April 2011 Miyagi earthquake

7.1 Mw earthquake near Miyagi Prefecture, Japan

April 2011 Miyagi earthquake2011年 宮城県沖地震

11 March quake

Sendai

UTC time| 2011-04-07 14:32:44
ISC event| 16413596
USGS-ANSS| ComCat
Local date| 7 April 2011 (2011-04-07)
Local time| 23:32 JST
Magnitude| 7.1 Mw [1]
Depth| 49 km (30 mi)
Epicenter| 38°15′11″N 141°38′24″E﻿ / ﻿38.253°N 141.640°E﻿ / 38.253; 141.640
Type| Thrust
Areas affected| Japan
Max. intensity| VIII (Severe) [2]

JMA 6+ [3]
Peak acceleration| 1.47 g [4]
Casualties| 4 confirmed dead, 141 injured[5]

The April 2011 Miyagi earthquake (2011年 宮城県沖地震, 2011-Nen Miyagi-ken-oki jishin) occurred off the coast of Miyagi Prefecture, approximately 66 kilometres (41 mi) east of Sendai, Japan. The Mw7.1 thrust earthquake was classified as an aftershock of the March 11 Tōhoku earthquake, and occurred at 23:32 JST (14:32 UTC) on Thursday, 7 April 2011.

Several tsunami warnings were issued for the northeastern coast of Honshu; however, they were all canceled 90 minutes later.[6] Over 3 million households in the area were left without power, and several nuclear plants suffered minor malfunctions. There was no major structural damage, but the quake killed at least 4 people and injured 141.[7]

## Earthquake[edit]

The Mw7.1 submarine earthquake occurred at a focal depth of 49 km (30.4 mi) in the western Pacific Ocean on 7 April 2011 at 14:21 UTC, approximately 66 km (41 mi) east of Sendai. The quake was a direct result of thrust faulting on or near the subduction zone plate boundary between the Pacific and North American Plates. Initially estimated at a magnitude of 7.4, the tremor was felt in several areas near the east coast of Honshu as an aftershock of the 11 March magnitude 9.0 megathrust Tōhoku earthquake. The aftershock sequence of this event is ongoing since 11 March, and includes over 58 earthquakes of magnitude 6.0 or greater up until 7 April 2011, with only two others of magnitude 7.0 or greater.[1]

## Damage and casualties[edit]

Although the quake was located several miles offshore, moderate to very strong shaking was reported as far inland as Tokyo, about 333 km (207 mi) from the epicentre.[8] Upon the detection of the earthquake, the Japan Meteorological Agency issued a tsunami warning for Miyagi Prefecture, as well as tsunami alerts for Iwate Prefecture, Fukushima Prefecture, Aomori Prefecture, Ibaraki Prefecture and the Pacific Rim. Waves of between 0.5 and 1 m were anticipated, and residents along coastal areas were urged to evacuate. All warnings and alerts were canceled within 90 minutes, however.[9]

The tremor caused widespread power outages, with power still not restored to some 3.6 million households across several prefectures by 8 April.[10] Nuclear power plants within the region also suffered from the outages; two of three power lines supplying power to fuel coolers were cut off at the Onagawa power plant.[11] Radioactive water consequently leaked out of spent fuel pools at three of its reactors, though no change in the radiation levels outside the plant was reported.[12] Five coal-powered power plants also shut down, adding to concerns over energy shortages. Fukushima I power plant, which had earlier been struck by the 11 March quake, evacuated its workers as a safety precaution, but the plant sustained no further damage from this quake.[10]

Four people were reported dead as a result of the earthquake, including an elderly woman in Yamagata Prefecture who lost power to her medical ventilator.[5] An additional 141 people suffered minor injuries, ranging from cuts and bruises to bone fractures.[11] No major losses were reported, though some roads sustained damage, as well as a few homes.[13] The Nikkei index fell sharply at the close of trading, but rebounded the next day when reports of limited damage were confirmed.[14]

## See also[edit]

* List of earthquakes in 2011
* List of earthquakes in Japan
* March 2021 Miyagi earthquake

## References[edit]

1. ^ a b "Magnitude 7.1 – NEAR THE COAST OF HONSHU, JAPAN". earthquake.usgs.gov. USGS. 7 April 2011. Archived from the original on 14 April 2011. Retrieved 2011-04-09.
2. ^ "PAGER – M 7.1 – NEAR THE EAST COAST OF HONSHU, JAPAN". earthquake.usgs.gov. USGS. 7 April 2011. Retrieved 2011-04-20.
3. ^ "震度データベース検索 （地震別検索結果）". Japan Meteorological Agency (in Japanese). Japan. Archived from the original on 16 July 2020. Retrieved 16 April 2021.
4. ^ "Shakemap usc0002ksa". earthquake.usgs.gov. Archived from the original on 4 March 2016. Retrieved 12 January 2022.
5. ^ a b Staff Writer (8 April 2011). "4 killed, 141 injured after 7.4 quake hits Miyagi Pref, vicinity". Japan Today. Retrieved 2011-04-08.
6. ^ Rubinsky, Cara (7 April 2011). "Japan lifts new tsunami warning after 7.4 quake". Associated Press. Retrieved 2011-04-08.
7. ^ Cooper, Hayden (April 8, 2011). "Japan aftershock kills four, dozens injured". radioaustralianews.au.net. ABC Radio Australia News. Archived from the original on 2011-04-08. Retrieved 2011-04-08.
8. ^ Staff Writer (7 April 2011). "Japan Earthquake Today: Minor Damages, Nuclear Plane Intact". International Business Times. Retrieved 2011-04-08.
9. ^ "Japan's Meteorological Agency lifted a tsunami warning". ytwhw.com. 8 April 2011. Archived from the original on 22 March 2012. Retrieved 2011-04-08.
10. ^ a b Tabuchi, Hiroko (9 April 2011). "Aftershock hits Japan, knocks out power at nuclear plants". theage.com.au. The Age. Retrieved 2011-04-09.
11. ^ a b Stanglin, Douglas (7 April 2011). "New quake disrupts power to cooling unit at nuclear plant". content.usatoday.com. USA Today. Retrieved 2011-04-09.
12. ^ Staff Writer (8 April 2011). "Japan's Onagawa Nuclear Plant Loses Power in Latest Quake". ens-newswire.com. Environment News Service. Retrieved 2011-04-09.
13. ^ CNN Wire Staff (8 April 2011). "Fresh aftershock in Japan rouses fear, kills 2". edition.cnn.com. CNN. Retrieved 2011-04-17. `{{cite web}}`: `|author=` has generic name (help)
14. ^ Staff Writer (8 April 2011). "More Japan Stocks Drop After Magnitude 7.1". SFGate. Retrieved 2011-04-09.

## External links[edit]

* The International Seismological Centre has a bibliography and/or authoritative data for this event.

* 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

|

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

* v
* t
* e

← Earthquakes in 2011 →

January|

* Tirúa, Chile (7.1, Jan 2)
* Balochistan, Pakistan (7.2, Jan 19)

February|

* Christchurch, New Zealand (6.3, Feb 22)†

March|

* Sendai, Japan (7.2, Mar 9)
* Yunnan, China (5.4, Mar 10)
* Tōhoku, Japan (Great East Japan) (9.1, Mar 11)†‡
* Sakae, Japan (6.7, Mar 11)
* Nagano, Japan (6.7, Mar 12)
* Shizuoka, Japan (6.0, Mar 15)
* Shan State, Myanmar (6.8, Mar 24)†

April|

* Miyagi, Japan (7.1, Apr 7)
* Fukushima, Japan (6.6, Apr 11)

May|

* Guerrero, Mexico (5.7, May 5)
* Lorca, Spain (5.1, May 11)
* Simav, Turkey (5.8, May 19)

June|

* Christchurch, New Zealand (6.3, June 13)

July|

* Fergana Valley (Uzbekistan, Kyrgyzstan and Tajikistan) (6.2, July 19)

August|

* Trinidad, Colorado (5.3, Aug 22)
* Mineral, Virginia (5.8, Aug 23)

September|

* Aceh Singkil, Indonesia (6.7, Sep 6)
* Sikkim, India (6.8, Sep 18)†

October|

* Van, Turkey (7.2, Oct 23)†

November|

* Prague, Oklahoma (5.7, Nov 6)
* Van, Turkey (5.6, Nov 10)†

December|

* Guerrero, Mexico (6.5, Dec 10)

† indicates earthquake resulting in at least 30 deaths
‡ indicates the deadliest earthquake of the year

* 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
* 1677 Bōsō
* 1703 Genroku
* 1707 Hōei
* 1741 Kampo
* 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
* 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
* April 2011 Miyagi
* April 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 Ishikawa
* 2024 Ishikawa

Related articles|

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

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