A tsunami is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and underwater explosions above or below water all have the potential to generate a tsunami. Unlike normal ocean waves, which are generated by wind, or tides, which are in turn generated by the gravitational pull of the Moon and the Sun, a tsunami is generated by the displacement of water from a large event.
On 26 December 2004, at 07:58:53 local time (UTC+7), a major earthquake with a magnitude of 9.2–9.3 struck with an epicentre off the west coast of Aceh in northern Sumatra, Indonesia. The undersea megathrust earthquake, known by the scientific community as the Sumatra–Andaman earthquake, was caused by a rupture along the fault between the Burma plate and the Indian plate, and reached a Mercalli intensity of IX in some areas.
The Manila Trench is an oceanic trench in the Pacific Ocean, located west of the islands of Luzon and Mindoro in the Philippines. The trench reaches a depth of about 5,400 metres (17,700 ft), in contrast with the average depth of the South China Sea of about 1,500 metres (4,900 ft). It is created by subduction, in which the Sunda Plate is subducting under the Philippine Mobile Belt, producing this almost N-S trending trench. The convergent boundary is terminated to the north by the Taiwan collision zone, and to the south by the Mindoro terrane. It is an area pervaded by negative gravity anomalies.
An earthquake occurred on July 17, 2006, at along a subduction zone off the coast of west and central Java, a large and densely populated island in the Indonesian archipelago. The shock had a moment magnitude of 7.7 and a maximum perceived intensity of IV (Light) in Jakarta, the capital and largest city of Indonesia. There were no direct effects of the earthquake's shaking due to its low intensity, and the large loss of life from the event was due to the resulting tsunami, which inundated a 300 km (190 mi) portion of the Java coast that had been unaffected by the earlier 2004 Indian Ocean earthquake and tsunami that was off the coast of Sumatra. The July 2006 earthquake was also centered in the Indian Ocean, 180 kilometers (110 mi) from the coast of Java, and had a duration of more than three minutes.
The 1922 Vallenar earthquake occurred with a moment magnitude of 8.5–8.6 and a tsunami magnitude of 8.7 in the Atacama Region of Chile, near the border with Argentina on 11 November at 04:32 UTC. It triggered a destructive tsunami that caused significant damage to the coast of Chile and was observed as far away as Australia.
The 1976 Moro Gulf earthquake and tsunami occurred on near the islands of Mindanao and Sulu, in the Philippines. It measured 8.0 on the moment magnitude scale occurring at a depth of 20 km (12 mi). The earthquake was accompanied by a destructive tsunami that resulted in a majority of the estimated 5,000 to 8,000 fatalities. It was the deadliest and strongest earthquake in the Philippines in 58 years since the 1918 Celebes Sea earthquake.
The 1896 Sanriku earthquake was one of the most destructive seismic events in Japanese history. The 8.5 magnitude earthquake occurred at 19:32 on June 15, 1896, approximately 166 kilometres (103 mi) off the coast of Iwate Prefecture, Honshu. It resulted in two tsunami waves which destroyed about 9,000 homes and caused at least 22,000 deaths. The waves reached a then-record height of 38.2 metres (125 ft); this would remain the highest on record until waves from the 2011 Tōhoku earthquake exceeded that height by more than 2 metres.
The 2010 Chile earthquake and tsunami occurred off the coast of central Chile on Saturday, 27 February at 03:34:12 local time, having a magnitude of 8.8 on the moment magnitude scale, with intense shaking lasting for about three minutes. It was felt strongly in six Chilean regions that together make up about 80 percent of the country's population. According to the United States Geological Survey (USGS) the cities experiencing the strongest shaking—VIII (Severe) on the Mercalli intensity scale (MM)—were Concepción, Arauco, and Coronel. According to Chile's Seismological Service, Concepción experienced the strongest shaking at MM IX (Violent). The earthquake was felt in the capital Santiago at MM VII or MM VIII. Tremors were felt in many Argentine cities, including Buenos Aires, Córdoba, Mendoza, and La Rioja. Tremors were felt as far north as the city of Ica in southern Peru. It is the largest earthquake to hit Chile since the 1960 Valdivia earthquake. A 2014 study contended that water pressure built up between the two plates had been the catalyst.
The 1996 Biak earthquake, or the Irian Jaya earthquake, occurred on 17 February at near Biak Island, Indonesia. The earthquake, which occurred on the New Guinea Trench, had a moment magnitude of 8.2 and a maximum Mercalli intensity of IX (Violent). The run-up height of the generated tsunami reached 7.7 m (25 ft). The disaster left at least 108 people dead, 423 injured, and 58 missing. It damaged or destroyed 5,043 houses which subsequently made another 10,000 homeless. At Korim, 187 houses were destroyed. Various countries and organizations provided aid and relief in the aftermath of the earthquake.
The 1953 Suva earthquake occurred on 14 September at 00:26 UTC near Suva, Fiji, just off the southeast shore of Viti Levu. This earthquake had an estimated magnitude of 6.8 and 6.4. The earthquake triggered a coral reef platform collapse and a submarine landslide that caused a tsunami. Eight people were reported killed.
The 1932 Jalisco earthquakes began on June 3 at 10:36 UTC with a megathrust event that registered 8.1 on the moment magnitude scale. With a maximum perceived intensity of X (Extreme) on the Mercalli intensity scale, at least 400 deaths were caused in Mexico and neighboring Guatemala. It was the first of a series of seismic events that affected parts of western Mexico during the month of June 1932, all reaching magnitude 7 or greater.
The 1927 Lompoc earthquake occurred on November 4 at 05:49 PST with an epicenter off the coast of Santa Barbara County Southern California. The earthquake measured 7.0 on the moment magnitude scale and had a maximum Modified Mercalli intensity of IX (Violent). It caused widespread damage in several towns of Santa Barbara County. A 2 m tsunami damaged railroad infrastructure and was recorded in Hawaii. There were no injuries or deaths from the earthquake.
The 1867 Virgin Islands earthquake and tsunami occurred on November 18, at 14.45 in the Anegada Passage about 20 km southwest of Saint Thomas, Danish West Indies. The Ms 7.5 earthquake came just 20 days after the devastating San Narciso Hurricane in the same region. Tsunamis from this earthquake were some of the highest ever recorded in the Lesser Antilles. Wave heights exceeded 10 m (33 ft) in some islands in the Lesser Antilles. The earthquake and tsunami resulted in no more than 50 fatalities, although hundreds of casualties were reported.
The devastating eruption of Oshima–Ōshima began on 18 August 1741 and ended on 1 May the next year. Eleven days into the eruption, the Kampo tsunami with estimated maximum heights of over 90 m (300 ft) swept across neighboring islands in Japan and the Korean Peninsula. The eruption and its resulting tsunami killed at least 1,400 people. Damage was extreme along the coast of Japan, while in Korea, the tsunami damaged fishing boats.
The Nemuro-Oki earthquake in scientific literature, occurred on June 17 at 12:55 local time. It struck with an epicenter just off the Nemuro Peninsula in northern Hokkaidō, Japan. It measured 7.8–7.9 on the moment magnitude scale (Mw ), 8.1 on the tsunami magnitude scale (Mt ) and 7.4 on the Japan Meteorological Agency magnitude scale (MJMA ).
An tsunamigenic earthquake occurred on 26 August 2012 at 22:37 CST with an epcenter off the coast of Usulután, El Salvador. It measured 7.3 on the moment magnitude scale and had a focal depth of 16.0 kilometres (10 mi). It was felt along the country's coast and in San Salvador although there was no damage. Along the San Juan del Gozo Peninsula, a tsunami triggered by the shock left 40 people injured. Waves were measured with a maximum run-up of 6.3 m (21 ft). The earthquake and tsunami was caused by a rupture on a subduction zone associated with the Middle America Trench.
An earthquake occurred off the coast of the Alaska Peninsula on July 28, 2021, at 10:15 p.m. local time. The large megathrust earthquake had a moment magnitude of 8.2 according to the United States Geological Survey (USGS). A tsunami warning was issued by the National Oceanic and Atmospheric Administration (NOAA) but later cancelled. The mainshock was followed by a number of aftershocks, including three that were of magnitude 5.9, 6.1 and 6.9 respectively.
The 1867 Keelung earthquake occurred off the northern coast of Taiwan on the morning of December 18 with a magnitude of 7.0. It produced strong shaking that seriously damaged the cities of Keelung and Taipei. A tsunami, thought to be the only confirmed destructive of its kind in Taiwan, drowned hundreds and had a run-up exceeding 15 m (49 ft). The total death toll was estimated to be 580 while more than 100 were injured. It was followed by aftershocks that were felt on average ten times a day.
The Shōnai offshore earthquake occurred at around 14:00 on December 7, 1833. It struck with an epicenter in the Sea of Japan, off the coast of Yamagata Prefecture, Japan. A tsunami was triggered by the estimated MJMA 7.5–7.7 earthquake. One hundred and fifty people were killed and there was severe damage in the prefecture.
The 1940 Shakotan earthquake occurred on August 2 at 00:08:22 JST with a moment magnitude (Mw ) of 7.5 and maximum JMA seismic intensity of Shindo 4. The shock had an epicenter off the coast of Hokkaido, Japan. Damage from the shock was comparatively light, but the accomanying tsunami was destructive. The tsunami caused 10 deaths and 24 injuries on Hokkaido, and destroyed homes and boats across the Sea of Japan. The highest tsunami waves were recorded at the coast of Russia while along the coast of Hokkaido, waves were about 2 m.
