2024 Sea of Japan earthquake

2024 Sea of Japan earthquake

File:USGS Intensity Map January 1 2024 Anamizu Earthquake M 7.5.pdf
Magnitude	7.6 ṃ 7.5 ṃ
Depth	10 km (6 mi) (USGS)
Epicenter
Type	Reverse
Areas affected	Japan
Max. intensity	Template:JMA IX (Violent)
Tsunami	1.2 m (3.9 ft)
Foreshocks	5.7 ṃ
Aftershocks	≥60, largest being 6.1 ṃ
Casualties	5 dead, 72+ injured, 1 cardiac arrest

On 1 January 2024, at 16:10 JST (07:10 UTC), a ṃ7.6 or ṃ7.5 earthquake struck the Noto Peninsula of Ishikawa Prefecture, Japan. The earthquake also generated a tsunami measuring up to 1.2 m (4 ft) along the Sea of Japan.

The Japan Meteorological Agency officially named this earthquake the 2024 Noto Peninsula Earthquake (Japanese: 令和6年能登半島地震, Hepburn: Reiwa 6-nen Noto-hantō Jishin).

Tectonic setting

Main article: Eastern margin of the Sea of Japan

The northeastern tip of the Noto Peninsula has been subject to an earthquake swarm for three years; the earthquake is the largest event in this swarm so far, surpassing a M_w 6.3 event that took place in May 2023. The earthquake was the strongest to hit the Sea of Japan region since 1983.

Japan is situated on a convergent boundary between the Pacific, Philippine Sea, Okhotsk and Amurian Plates. Along the island arc's east and southeast coasts, subduction of the Pacific and Philippine Sea Plates occurs at the Japan Trench and Nankai Trough, respectively. The west coast of Honshu, bordering the Sea of Japan, is a north–south trending convergent boundary. This boundary between the Amurian and Okhotsk Plates is thought to be an incipient subduction zone, consisting of eastward-dipping thrust faults. Convergent tectonics have been occurring in the region since the end of the Pliocene. Earthquakes and tsunamis are produced on thrust faults that form the boundary, with magnitudes in the range of 6.8–7.9. Major earthquakes and tsunamis along this boundary occurred in 1741, 1833, 1940, 1964, 1983 and 1993, although the origin of the 1741 tsunami remains open to debate.

Earthquake

The United States Geological Survey (USGS) reported a moment magnitude of 7.5 and a focal depth of 10 km (6.2 mi) for the earthquake. The Japan Meteorological Agency recorded a magnitude of ṃ 7.6. The focal mechanism of the mainshock corresponded to shallow reverse faulting along a northeast-trending plane dipping northwest or southeast, happening along the convergent boundary between the Okhotsk Plate and Amurian Plate. A magnitude 5.5 foreshock struck four minutes before the mainshock, while a magnitude 6.2 aftershock struck nine minutes later. About 60 aftershocks were recorded after the earthquake, with at least seven of them registering a magnitude of 5.0 and above.

File:USGS Finite Fault Surface Projection January 1 2024 Anamizu Earthquake M 7.5.png

USGS generated Finite Fault Surface Projection

According to a finite fault model released by the USGS, the earthquake rupture extended approximately 200 km (120 mi) from southeast of the Noto Peninsula to Sado Island along a southeast-dipping fault. The zones of the largest slip occurred northeast and southwest of the hypocenter. The latter patch produced the largest displacement of 3.67 m (12 ft) beneath the peninsula. Another zone of slip occurred between the peninsula and Sado Island, producing up to 1.86 m (6 ft) of slip. The fault likely ruptured towards the seafloor.

Intensity

The Japan Meteorological Agency said it recorded a maximum seismic intensity of 7 (Shindo 7), the highest level on its seismic intensity scale. It is the first time that an earthquake of that intensity has been observed in the country since 2018. The maximum intensity was reported in Shika, Ishikawa Prefecture. Intensity 6+ was recorded in Nanao, Wajima, Suzu and Anamizu. Intensity 6– was recorded in Nagaoka in Niigata Prefecture and in Ishikawa's Nakanoto and Noto. The earthquake was also felt by residents in Tokyo and across the Kanto Region and as far as Aomori Prefecture in the northern tip of Honshu to Kyushu in the south of the country.

Locations with a seismic intensity of Shindo 5- and higher

Intensity	Prefecture	Location
7	Ishikawa	Shika
6+	Ishikawa	Nanao, Wajima, Suzu, Anamizu
6-	Ishikawa	Nakanoto, Noto
	Niigata	Nagaoka
5+	Ishikawa	Hakui, Hōdatsushimizu, Kanazawa, Komatsu, Kaga, Kahoku, Nomi
	Niigata	Sanjō, Kashiwazaki, Mitsuke, Minamiuonuma, Kariwa, Itoigawa, Myōkō, Jōetsu, Chūō-ku, Minami-ku, Nishi-ku, Nishikan-ku, Tsubame, Aga, Sado
	Toyama	Toyama, Funahashi, Takaoka, Himi, Oyabe, Nanto, Imizu
	Fukui	Awara
5-	Ishikawa	Hakusan, Tsubata, Uchinada
	Niigata	Ojiya, Kamo, Tōkamachi, Izumozaki, Kita-ku, Higashi-ku, Kōnan-ku, Akiha-ku, Gosen, Agano
	Toyama	Namerikawa, Kurobe, Kamiichi, Tateyama, Asahi, Tonami
	Fukui	Fukui, Sakai
	Nagano	Nagano, Shinano, Sakae
	Gifu	Takayama, Hida

Tsunami

Japan

File:JMA Tsunami Warnings 1 January 2024 en.png

Map of Tsunami Warnings issued by the Japan Meteorological Agency at 1 January 2024 16:22 JST

Large parts of Japan's western coast, from Hokkaido to Nagasaki Prefectures were immediately placed under a tsunami warning after the earthquake struck, with evacuation orders issued in Ishikawa, Niigata, Toyama, and Yamagata prefectures. The earthquake triggered a major tsunami warning, the first one since the 2011 Tōhoku earthquake. Public broadcaster NHK said tsunami waves of 5 m (16 ft) could be expected, though much smaller waves later arrived. The Pacific Tsunami Warning Center said dangerous tsunami waves were possible within 300 km (190 mi) of the epicenter. The evacuation orders affected 51,000 people, with 1,000 evacuees finding shelter at the Japan Air Self-Defense Force base in Wajima in Ishikawa Prefecture alone.

The first waves were reported to have arrived at around 16:21, with tsunami waves exceeding 1.2 m (4 ft) striking Wajima. A tsunami measuring 90 cm (35 in) struck Kanazawa, while a tsunami of 80 cm (31 in) struck Toyama Prefecture and Sakata, Yamagata Prefecture. Waves measuring 50 cm (20 in) were recorded in Nanao and Tsuruga while waves measuring 40 cm (16 in) were recorded at Kashiwazaki, Toyooka, Tobishima, and Sado Island. In Toyama city, a 0.5 m (1 ft 8 in) wave was reported. In Hokkaido, waves of up to 60 cm (24 in) were reported in Setana, while 50 cm (20 in) waves struck Okushiri Island.

The major tsunami warning was later downgraded to a tsunami warning at 20:30, about four hours after the earthquake.

Elsewhere along the Sea of Japan

The coastlines of Gangwon Province and Pohang in South Korea could experience a rise in sea levels according to the Korea Meteorological Administration. Waves of 0.3 m (1 ft) were anticipated along the nation's east coast from 18:29 to 19:17 local time. A 0.45 m (1 ft 6 in) tsunami was later reported to have occurred in Gangwon. A 0.67 m (2 ft) high wave reportedly struck Mukho at around 20:00 local time. According to Yonhap News Agency, citing North Korean state radio, a tsunami warning was issued with waves of 2.08 m (6 ft 10 in) potentially hitting the country's east coast.

Warnings for tsunami waves estimated to reach 1 m (3 ft) were also issued in Russia, particularly along the west coast of Sakhalin Island, where evacuations were conducted, although Russia later said that no evacuations were taking place there. Tsunami warnings were also declared in Vladivostok and Nakhodka. The Emergencies Ministry of Russia said "response teams are ready to deal with the possible consequences of a tsunami."

Impact

At least five people died; all of them were attributed to collapsing houses. Two people died in Nanao, one death occurred in Shika, one died in Hakui, and another was killed in Wajima.

In Wajima, at least 50 houses collapsed. A fire occurred in the city at 17:00. Due to damaged roads, firefighters were unable to extinguish the flames, which consumed a row of several homes. More than 30 people were injured in the city, while many more injuries were reported in Suzu, where many houses were engulfed in flames. The Ishikawa Nanao Police Station said collapsed homes trapped people before they were rescued. At least 10 people were buried by collapsed homes, according to the Asahi Shimbun while multiple injuries were reported by the local fire and health departments. A spokesperson at Wajima Municipal Hospital said people had broken bones or were injured by falling objects. Besides a fatality, one person was injured and two houses collapsed in Shika.

At least 18 people in Toyama Prefecture were injured, eight of them after the ceiling of a pachinko parlor collapsed in Toyama City. Over 100 buildings were damaged. In Niigata Prefecture, 14 people were injured, many buildings collapsed, and roads were damaged. One cardiac arrest case was reported in an elderly person in the prefecture, likely linked to the earthquake. In Fukui Prefecture, five people sustained minor injuries. Two injuries were also reported each in Osaka and Hyōgo Prefectures, while an unspecified number of injuries were reported in Gifu Prefecture.

Cracked roads and broken water mains were reported in the cities of Himi and Oyabe, Toyama Prefecture. Liquefaction occurred in Niigata city; sewer pipes also ruptured and many homes were left without water. The Onohiyoshi Shrine in Kanazawa also sustained damage. A landslide struck the main expressway between Toyama and Kanazawa, ripping apart several hundred meters of roadway.

NTT Docomo, Rakuten Mobile, Softbank and KDDI reported telecommunications and internet service disruptions in Ishikawa and Niigata prefectures, while NTT West said its facilities were damaged by the earthquake. At the Shika Nuclear Power Plant in Ishikawa Prefecture, an explosion occurred near the power transformer of the No.2 reactor, while the transformer at the No.1 reactor was rendered inoperable due to an oil spill. At least 36,000 households lost power following the earthquake.

Response

Prime Minister Fumio Kishida announced the establishment of a special emergency center to gather and disseminate information on the earthquake and tsunami. Defense minister Minoru Kihara ordered the Japan Self-Defense Forces (JSDF) to assist in rescue efforts. He later announced the deployment of 1,000 JSDF personnel to the affected region, with 8,500 others on standby. About 20 JSDF aircraft were also dispatched to survey the damage.

Kansai Electric Power Company, Tokyo Electric Power Company and Hokuriku Electric Power Company said they were inspecting their nuclear power plants for abnormalities. Both the Kansai and Hokuriku Electric Power Companies later said no abnormalities were reported, with the reactors at the latter's Shika Nuclear Power Plant in Ishikawa Prefecture having been closed for inspections at the time of the earthquake. The Japanese Nuclear Regulation Authority also found no irregularities in power plants along the Sea of Japan coastline. Hokuriku Electric Power Company also shut down two generators at its Nanao Ota thermal power plant in Nanao.

Shinkansen services were suspended in central and eastern parts of Japan following the earthquake, stranding at least 1,400 passengers aboard four stalled trains. Several major highways in the affected areas were also closed. All Nippon Airways and Japan Airlines cancelled flights to Toyama, Ishikawa, and Niigata prefectures.

See also

• List of earthquakes in 2024
• List of earthquakes in Japan
• 2007 Noto earthquake
• 2023 Ishikawa earthquake