Search Posts


Tokai earthquakes|||| Tokai earthquakes is located in JapanTokai earthquakes is located in Japan
external image 50px-Bullseye1.png

every 100–150 years
at least 8 ML
Countries or regions affected
external image 22px-Flag_of_Japan.svg.pngJapan: Tokai region
The Tokai earthquakes are major earthquakes that have occurred regularly with an interval of 100 to 150 years in the Tokai region of Japan. The Tokai segment has been struck by earthquakes in 1498, 1605, 1707 and 1854.[1] Given the historic regularity of these earthquakes, another is expected in the near future. The Japanese government is taking the Tokai earthquakes seriously and has charged the Japan Meteorological Agency with the job of predicting the next one. They have a dense array of instruments placed to accumulate a continuous stream of data related to seismicity, strain, crustal expansion, tilt, tidal variations, ground water fluctuations and other variables. They are watching for an anomaly in this data which might precede the next major Tokai earthquake.
Given the magnitude of the last two earthquakes, the next is expected to be at least a magnitude 8, with large areas shaken at an intensity of 7, the highest level in the Japanese intensity scale. Emergency planners are anticipating and preparing for potential scenarios after such an earthquake, including the possibility of thousands of deaths and injuries and millions of damaged buildings.


[edit] Relation to other major earthquakes

external image 240px-RuptureAreasNankaiMegathrust.pngexternal image magnify-clip.png
Nankai, Tonankai and Tokai earthquake areas
The pattern of historical seismicity reveals that the megathrust surface is segmented, with five separate zones of rupturing identified, conventionally labeled A–E, from west to east.[2] Earthquakes involving the A+B segments are generally referred to as Nankai (literally South Sea) earthquakes, C+D Tonankai (literallySoutheast Sea) earthquakes and E Tokai (literally East Sea) earthquakes. The earthquake repeat intervals are generally in the range 90–200 years.
On all but one occasion, rupture of segment C (±­D ±E) has been followed by rupture of segments A+B within a few years. This behavior has been reproduced by modeling the viscoelastic response of the megathrust fault plane with lateral variations in both convergence rate and frictional properties.[2]

[edit] Historical Tokai earthquakes

Death toll
November 26, 684
Hakuho earthquake
Landslides. Many houses, shrines and temples collapsed.
August 22, 887
Ninna earthquake
Many people died in collapsing houses.
December 11, 1096
Kowa earthquake
The main building of the imperial palace was damaged, and the big bell of the Todai temple fell down. The tsunami in Suruga spilt houses, and 400 shrines and temples were damaged.
July 26, 1361
Shohei earthquake
To be described.
September 11, 1498
Meio earthquake
Kai had a major shake. The building around great Buddha of Kamakura (altitude 7m) was swept away by the tsunami. In Minato Hiroshi 1,000 households was destroyed, 5,000 people drowned. 10,000 people drowned in Ise-Shima, in Shida District, Shizuoka Prefecture, 26,000 people died. Nankai earthquakes also occurred around the same time according to the geological survey.
February 3, 1605
Keicho earthquake
The tsunami attack from the Pacific coast of Kyushu, Miyazaki, led to that 57 people died in Hachijo Island, destroyed 700 houses in a village west of Kii wide, 1,500 people died in Shishikui Awa, Tosa Nishinoura 350 deaths, and 400 in the vicinity of Cape Muroto.
October 28, 1707
Hoei earthquake
Tokai, Tonankai and Nankai earthquakes occurred at the same time with magnitude 8.4–8.6.Mount Fuji erupted 49 days after this earthquake and the Hoei crater was created. About 20,000 people were killed and 60,000 houses collapsed, the Tosa area was affected by the tsunami.
December 23, 1854
Ansei-Tokai earthquake
The epicenter ranged from Suruga Bay to the deep ocean, and struck primarily in the Tokai region, but destroyed houses as far away as in Edo. The accompanying tsunami caused damage along the entire coast from the Boso Peninsula in modern-day Chiba prefecture to Tosa province (modern-day Kochi prefecture).[3]

[edit] See also

[edit] References

  1. ^ [1]
  2. ^ //**a**// //**b**// Hirahara, K.; Kato N., Miyatake T., Hori T., Hyodo M., Inn J., Mitsui N., Sasaki T., Miyamura T., Nakama Y. & Kanai T. (2004). "Simulation of Earthquake Generation Process in a Complex System of Faults". Annual Report of the Earth Simulator Center April 2004 – March 2005. pp. 121–126. Retrieved 2009-11-14.
  3. ^ Kawade Shobo Shinsha Editorial Team (eds.). "Ansei Daijishin" (?????, "Great Earthquakes of Ansei"). O-Edo Rekishi Hyakka (???????, "Historical Encyclopedia of Great Edo"). Tokyo: Kawade Shobo Shinsha Publishers, 2007. p253.

[edit] External links

Retrieved from ""
Categories: Megathrust earthquakes in Japan

Personal tools





    • This page was last modified on 16 March 2011 at 02:00.

external image Megatsunami-coast.jpgexternal image magnify-clip.png
A depiction of wave shoaling.
This article lists notable historic tsunamis, which are sorted by the date and location that the tsunami occurred, the earthquake that generated it, or both.
Because of seismic and volcanic activity at tectonic plate boundaries along the Pacific Ring of Fire, tsunamis occur most frequently in the Pacific Ocean, but are worldwide natural phenomena. They are possible wherever large bodies of water are found, including inland lakes, where they can be caused by landslides and glacier calving. Very small tsunamis, non-destructive and undetectable without specialized equipment, occur frequently as a result of minor earthquakes and other events.
As early as 426 BC, the Greek historian Thucydides inquired in his book History of the Peloponnesian War (3.89.1-6) about the causes of tsunamis. He argued rightly that it could only be explained as a consequence of ocean earthquakes, and could see no other possible causes for the phenomenon.[1]
Crete and the Argolid and other locations were destroyed by a tsunami caused by the eruption of Thira, which destroyed Minoan civilization on Crete and related cultures in the Cyclades and in areas facing the eruption on the Greek mainland such as the Argolid.
During the Persian siege of the sea town Potidaea, Greece, in 479 BC,[2] the Greek historian Herodotus reports how the Persian attackers who tried to exploit an unusual retreat of the water were suddenly surprised by "a great flood-tide, higher, as the people of the place say, than any one of the many that had been before". Herodotus attributes the cause of the sudden flood to the wrath of Poseidon.[3]


[edit] Before 1000 AD

[edit] ˜1600 BC: Santorini, Greece

Main article: Minoan eruption
The volcanic eruption on Santorini, Greece is assumed to have caused severe damage to cities around it, most notably the Minoan civilization on Crete. A tsunami is assumed to be the factor that caused the most damage.

[edit] 426 BC: Maliakos Gulf, Greece

Main article: 426 BC Maliakos Gulf tsunami
In the summer of 426 BC, a tsunami hit hard the Maliakos bay in Eastern Greece.[4] The Greek historian Thucydides (3.89.1-6) described how the tsunami and a series of earthquakes intervened with the events of the raging Peloponnesian War (431-404 BC) and correlated for the first time in the history of natural science quakes and waves in terms of cause and effect.[5]

[edit] 373 BC: Helike, Greece

An earthquake and a tsunami destroyed the prosperous Greek city Helike, lying 2 km away from the sea. The fate of the city, which remained permanently submerged, was often commented upon by ancient writers[6] and may have inspired the contemporary Plato to the myth of Atlantis.

[edit] 365 AD: Alexandria, Eastern Mediterranean

Main article: 365 Crete earthquake
In the morning of July 21, 365 AD, an earthquake of great magnitude caused a huge tsunami more than 100 feet high. It devastated Alexandria and the eastern shores of the Mediterranean, killing thousands and hurling ships nearly two miles inland.[7][8] The Roman historian Ammianus Marcellinus (Res Gestae 26.10.15-19) describes in his vivid account the typical sequence of the tsunami including an incipient earthquake, the sudden retreat of the sea and a following gigantic wave:

  • Slightly after daybreak, and heralded by a thick succession of fiercely shaken thunderbolts, the solidity of the whole earth was made to shake and shudder, and the sea was driven away, its waves were rolled back, and it disappeared, so that the abyss of the depths was uncovered and many-shaped varieties of sea-creatures were seen stuck in the slime; the great wastes of those valleys and mountains, which the very creation had dismissed beneath the vast whirlpools, at that moment, as it was given to be believed, looked up at the sun's rays. Many ships, then, were stranded as if on dry land, and people wandered at will about the paltry remains of the waters to collect fish and the like in their hands; then the roaring sea as if insulted by its repulse rises back in turn, and through the teeming shoals dashed itself violently on islands and extensive tracts of the mainland, and flattened innumerable buildings in towns or wherever they were found. Thus in the raging conflict of the elements, the face of the earth was changed to reveal wondrous sights. For the mass of waters returning when least expected killed many thousands by drowning, and with the tides whipped up to a height as they rushed back, some ships, after the anger of the watery element had grown old, were seen to have sunk, and the bodies of people killed in shipwrecks lay there, faces up or down. Other huge ships, thrust out by the mad blasts, perched on the roofs of houses, as happened at Alexandria, and others were hurled nearly two miles from the shore, like the Laconian vessel near the town of Methone which I saw when I passed by, yawning apart from long decay.[7]

The tsunami in 365 AD was so devastating that the anniversary of the disaster was still commemorated annually at the end of the 6th century in Alexandria as a "day of horror."[9]
Researchers at the University of Cambridge recently carbon dated corals on the coast of Crete which were lifted 10 metres and clear of the water in one massive push. This indicates that the tsunami of 365 AD was generated by an earthquake in a steep fault in the Hellenic trench near Crete. The scientists estimate that such a large uplift is only likely to occur once in 5,000 years, however the other segments of the fault could slip on a similar scale – and could happen every 800 years or so. It is unsure whether "one of the contiguous patches might slip in the future."[10]

[edit] 684 AD: Hakuho, Japan (?????)

Japan is the nation with the most recorded tsunamis in the world.[citation needed] The number of tsunamis in Japan totals 195 over a 1,313 year period (thru 1997), averaging one event every 6.73 years, the highest rate of occurrence in the world.[citation needed]
The Great Hakuho Earthquake was the first recorded tsunami in Japan. It hit in Japan on November 29, 684. It occurred off the shore of the Kii Peninsula,Nankaido, Shikoku, Kii, and Awaji region. It has been estimated to be a magnitude 8.4 [11] It was followed by a huge tsunami, but no estimates on how many deaths.[12]

[edit] 869 AD: Sendai, Japan

Main article: 869 Sanriku earthquake and tsunami
The Sendai region was struck by a major tsunami that caused flooding extending 4 km inland from the coast. The town of Tagajo was destroyed, with an estimated 1,000 casualties.

[edit] 887 AD: Ninna Nankai, Japan (??????)

On August 26 of the Ninna era, there was a strong shock in the Kyoto region, causing great destruction and some victims. At the same time, there was a strong earthquake in Osaka, Shiga, Gifu, and Nagano prefectures. A tsunami flooded the coastal locality, and some people died. The coast of Osaka and primarilyOsaka Bay suffered especially heavily from the tsunami. The tsunami was also observed on the coast of Hyuga-Nada.[11]

[edit] 1000–1700

[edit] 1293: Kamakura, Japan (?????)

Magnitude 7.1 Quake and tsunami hit Kamakura, Japan's de facto capital, killing 23,000 after resulting fires.

[edit] 1303: Eastern Mediterranean

Main article: 1303 Crete earthquake
A team from Southern Cross University in Lismore, New South Wales, Australia, has found geological evidence of five tsunamis that have hit Greece over the past 2000 years. "Most were small and local, but in 1303 a larger one hit Crete, Rhodes, Alexandria and Acre in Palestine."[13]

[edit] 1361: Shohei Nankai, Japan (?? & ??)????)

On Aug 3 of the Shohei era, a 8.4 Nankaido quake and tsunami hit, with 660 deaths, 1700 houses destroyed. There was a strong earthquake in Tokushima, Osaka, Wakayama, and Nara Prefectures and on Awaji Island. A tsunami was observed on the coast of Tokushima and Kochi Prefectures, in Kii Strait and in Osaka Bay.Yunomine Hot Spring (Wakayama Prefecture) stopped. Yukiminato, Awa completely destroyed by tsunami and more than 1,700 houses washed away. 60 persons drowned at Awa.

[edit] 1498: Meio Nankai, Japan (????)

Main article: 1498 Meio Nankaido earthquake
Sep 20 7.5 Quake and tsunami hit in the Meio era. Port in Wakayama damaged by tsunami of several meters in height.30-40 thousand deaths estimated.[11][14]The building around great Buddha of Kamakura (altitude 7m) was swept away by the tsunami.[15]

[edit] 1541: Nueva Cadiz, Venezuela

In 1528, Cristóbal Guerra founded the city "La Villa de la Nueva Cádiz" in the island of Cubagua, the first Spanish settlement in Venezuela, and one of the first ones in the Americas.[2] Nueva Cádiz, which reached a population between 1000 and 1500, was destroyed in an earthquake followed by tsunami in 1541.[3] The ruins were declared a National Monument of Venezuela in 1979.

[edit] 1605: Keicho Nankaido, Japan

On Feb 3 of the Keicho era, a 8.1 Quake and tsunami hit 700 houses (41%) at Hiro, Wakayama Prefecture washed away. 3,600 drowned in Shishikui area.Awa, wave height 6-7m. 350 at Kannoura 60 at Sakihama drowned, wave height 5–6 m and 8–10 m, respectively. Total more than 5,000 drowned. An enormous tsunami with a maximum known rise of water of 30 m was observed on the coast from the Boso Peninsula to the eastern part of Kyushu Island. The eastern part of the Boso Peninsula, the coast of Tokyo Bay, the coast of the prefectures of Kanagawa and Shizouka, and the southeastern coast of Kochi Prefecture suffered especially heavily.[11]

[edit] 1607: Bristol Channel, Great Britain

Main article: Bristol Channel floods, 1607
On 30 January 1607, approximately 2,000 or more people were drowned, houses and villages swept away and an estimated 200 square miles (518 km2) was inundated. Until the 1990s, it was undisputed that the flooding was caused by a storm surge aggravated by other factors, but recent research indicates a tsunami. The probable cause is postulated as a submarine earthquake off the Irish coast.

[edit] 1698: Seikaido-Nankaido, Japan

On December 22, 1698, a large tsunami struck Seikaido-Nankaido, Japan.[11]

[edit] 1700s

[edit] 1700: Vancouver Island, Canada

Main article: 1700 Cascadia earthquake
On January 26, 1700, the Cascadia earthquake, one of the largest earthquakes on record (estimated MW 9 magnitude), ruptured the Cascadia subduction zone(CSZ) offshore from Vancouver Island to northern California, and caused a massive tsunami across the Pacific Northwest logged in Japan and oral traditions of the Native Americans. Brian F. Atwater, Musumi-Rokkaku Satoko, Satake Kenji, Tsuji Yoshinobu, Ueda Kazue, and David K. Yamaguchi prepared a "scientific detective story" investigating this tsunami entitled The Orphan Tsunami of 1700—Japanese Clues to a Parent Earthquake in North America. This document is downloadable and available online.

[edit] 1707: Hoei, Japan (?????)

Main article: 1707 Hoei earthquake
On October 28, 1707, during the Hoei era, an 8.4 earthquake and tsunami 25.7-meter-high struck at the Kochi Prefecture. More than 29,000 houses in total wrecked and washed away and about 30,000 deaths. In Tosa, 11,170 houses washed away and 18,441 people drowned. About 700 drowned and 603 houses washed away in Osaka. 20 m high at Tanezaki, Tosa, 6.58 at Muroto. Hot springs at Yunomine, Sanji, Ryujin, Seto-Kanayana (Kii) and Dogo (Iyo,145 days) stopped.[11]

[edit] 1741: W. Hokkaido, Japan

On 29 August 1741 the western side of Hokkaido was hit by a tsunami associated with the eruption of the volcano on Oshima island. The cause of the tsunami is thought to have been a large landslide, partly submarine, triggered by the eruption.[16] 1,467 people were killed on Hokkaido and another 8 in Aomori Prefecture.[17]

[edit] 1755: Lisbon, Portugal

Main article: 1755 Lisbon earthquake
Tens of thousands of Portuguese people who survived the Great Lisbon Earthquake on November 1, 1755 were killed by a tsunami which followed 40 minutes later. Many townspeople fled to the waterfront, believing the area safe from fires and from falling debris from aftershocks. When at the waterfront, they saw that the sea was rapidly receding, revealing a sea floor littered with lost cargo and forgotten shipwrecks. The tsunami struck with a maximum height of 15 metres (49 ft), and went far inland.
The earthquake, tsunami, and many fires killed between 60,000 and 100,000 in Lisbon alone, making it one of the deadliest natural disasters in recorded history. Historical records of explorations by Vasco da Gama and other early navigators were lost, and countless buildings were destroyed (including most examples of Portugal's Manueline architecture). Europeans of the 18th century struggled to understand the disaster within religious and rational belief systems. Philosophers of the Enlightenment, notably Voltaire, wrote about the event. The philosophical concept of the sublime, as described by philosopher Immanuel Kant in theObservations on the Feeling of the Beautiful and Sublime, took inspiration in part from attempts to comprehend the enormity of the Lisbon quake and tsunami.
The tsunami took just over 4 hours to travel over 1,000 miles (1,600 km) to Cornwall in the United Kingdom. An account by Arnold Boscowitz claimed "great loss of life." It also hit Galway in Ireland, and caused some serious damage to the Spanish Arch section of the city wall.

[edit] 1771: Yaeyama Islands, Okinawa, Japan (?????)

Main article: 1771 Great Yaeyama Tsunami
An undersea earthquake of estimated magnitude 7.4 occurred near Yaeyama Islands in Okinawa, Japan on 4 April 1771 at about 8 A.M.. The earthquake is not believed to have directly resulted in any deaths, but a resulting tsunami is thought to have killed about 12,000 people, (9313 on the Yaeyama Islands and 2548 on Miyako Islands according to one source [18]). Estimates of the highest seawater runup on Ishigaki Island, range between 30 meters and 85.4 meters. The tsunami put an abrupt stop to population growth on the islands, and was followed by malaria epidemics and crop failures which decreased the population further. It was to be another 148 years before population returned to its pre-tsunami level. ja:?????

[edit] 1792: Mount Unzen, Nagasaki Prefecture, Kyushu, Japan (????????)

Main article: Mount Unzen
Tsunamis were the main cause of death for Japan's worst-ever volcanic disaster, due to an eruption of Mount Unzen in Nagasaki Prefecture, Kyushu, Japan. It began towards the end of 1791 as a series of earthquakes on the western flank of Mount Unzen which gradually moved towards Fugen-daké, one of Mount Unzen's peaks. In February 1792, Fugen-daké started to erupt, triggering a lava flow which continued for two months. Meanwhile, the earthquakes continued, shifting nearer to the city of Shimabara. On the night of 21 May, two large earthquakes were followed by a collapse of the eastern flank of Mount Unzen's Mayuyama dome, causing an avalanche which swept through Shimabara and into Ariake Bay, triggering a tsunami. It is not known to this day whether the collapse occurred as a result of an eruption of the dome or as a result of the earthquakes. The tsunami struck Higo Province on the other side of Ariake Baybefore bouncing back and hitting Shimabara again. Out of an estimated total of 15,000 fatalities, around 5,000 is thought to have been killed by the landslide, around 5,000 by the tsunami across the bay in Higo Province, and a further 5,000 by the tsunami returning to strike Shimabara. The waves reached a height of 330 ft, classing this tsunami as a small megatsunami.

[edit] 1800s

[edit] 1833: Sumatra, Indonesia

Main article: 1833 Sumatra earthquake
On 25 November 1833, a massive earthquake estimated to have been between 8.8-9.2 on the moment magnitude scale, struck Sumatra in Indonesia. The coast of Sumatra near the quake's epicentre was hardest hit by the resulting tsunami.

[edit] 1854: Nankai, Tokai, and Kyushu Japan (??????)

Main article: Ansei Great Earthquakes
The Ansei Quake which hit the south coast of Japan, was actually set of 3 quakes, two magnitude 8.4 quakes and a 7.4 quake all in 3 days.

      • The first on Nov 4, 1854 near what is today Aichi Prefecture and Shizuoka Prefecture with tsunami.
      • It was followed by another 8.4 the next day in Wakayama Prefecture, Earthquake generated a maximum wave of 28 meters at Kochi, Japan, and the earthquake that tsunami killed 3,000 people. The tsunami washed 15,000 homes away. The number of homes destroyed directly by the earthquake was 2,598; 1,443 people died.[11]
      • The third was a 7.4 quake on Nov 7, 1854 in Ehime Prefecture and Oita Prefecture.

The total result was 80,000-100,000 deaths.[19]

[edit] 1855: Edo, Japan (???????)

Main article: 1855 Ansei Edo earthquake
The following year, the 1855 Great Ansei Edo Quake hit (Tokyo region), killing 4,500 to 10,000 people. Popular stories of the time blamed the quakes and tsunamis on giant catfish called Namazu thrashing about. The Japanese era name was changed to bring good luck after 4 menacing quake/tsunamis in 2 years.

[edit] 1868: Hawaiian Islands

On April 2, 1868, a local earthquake with a magnitude estimated between 7.5 and 8.0 rocked the southeast coast of the Big Island of Hawai?i. It triggered a landslide on the slopes of the Mauna Loa volcano, five miles north of Pahala, killing 31 people. A tsunami then claimed 46 additional lives. The villages ofPunaluu, Ninole, Kawaa, Honuapo, and Keauhou Landing were severely damaged and the village of ?Apua was destroyed. According to one account, the tsunami "rolled in over the tops of the coconut trees, probably 60 feet high …. inland a distance of a quarter of a mile in some places, taking out to sea when it returned, houses, men, women, and almost everything movable." This was reported in the 1988 edition of Walter C. Dudley's book "Tsunami!" (ISBN 0-8248-1125-9).

[edit] 1868: Arica, Chile

On August 16, 1868, an earthquake with a magnitude estimated at 8.5 struck the oceanic trench currently known as the Peru-Chile Trench. A resulting tsunami struck the port of Arica, then part of Peru, killing an estimated 25,000 in Arica and 70,000 in all. Three military vessels anchored at Arica, the US warshipWateree and the storeship Fredonia, and the Peruvian warship America, were swept up by the tsunami.[20]

[edit] 1883: Krakatoa, Sunda Strait, Indonesia

Main article: 1883 eruption of Krakatoa
The island volcano of Krakatoa in Indonesia exploded with devastating fury on August 26–27, 1883, blowing its underground magma chamber partly empty so that much overlying land and seabed collapsed into it. A series of large tsunami waves was generated from the collapse, some reaching a height of over 40 meters above sea level. Tsunami waves were observed throughout the Indian Ocean, the Pacific Ocean, and even as far away as the American West Coast, and South America. On the facing coasts of Java and Sumatra the sea flood went many miles inland and caused such vast loss of life that one area was never resettled but reverted to the jungle and is now the Ujung Kulon nature reserve.

[edit] 1896: Meiji Sanriku, Japan (??????)

Main article: 1896 Meiji-Sanriku earthquake
On 15 June 1896, at around 19:36 local time, a large undersea earthquake off the Sanriku coast of northeastern Honshu, Japan, triggered tsunami waves which struck the coast about half an hour later. Although the earthquake itself is not thought to have resulted in any fatalities, the waves, which reached a height of 100 feet, killed approximately 27,000 people. In 2005 the same general area was hit by the 2005 Sanriku Japan Earthquake, but with no major tsunami.

[edit] 1900–1950

[edit] 1908: Messina, Italy

external image 220px-Messina_earthquake.jpgexternal image magnify-clip.png
The aftermath of the tsunami that struck Messina in 1908.
The 1908 Messina earthquake in Italy, triggered a large tsunami that took more than 70,000 lives.

[edit] 1923: Kanto, Japan (?????)

Main article: Great Kanto Earthquake
The Great Kanto Earthquake, which occurred in eastern Japan on 1 September 1923, and devastated Tokyo, Yokohama and the surrounding areas, caused tsunamis which struck the Shonan coast, Boso Peninsula, Izu Islands and the east coast of Izu Peninsula, within minutes in some cases. In Atami, waves reaching 12 meters were recorded. Examples of tsunami damage include about 100 people killed along Yuigahama beach in Kamakura and an estimated 50 people on the Enoshima causeway. However, tsunamis only accounted for a small proportion of the final death toll of over 100,000, most of whom were killed in fire.

[edit] 1929: Newfoundland

external image 250px-Burnintsunami.jpgexternal image magnify-clip.png
The aftermath of the tsunami that struckNewfoundland in 1929.
On November 18, 1929, an earthquake of magnitude 7.2 occurred beneath the Laurentian Slope on the Grand Banks. The quake was felt throughout the Atlantic Provinces of Canada and as far west as Ottawa and as far south as Claymont, Delaware. The resulting tsunami measured over 7 meters in height and took about 2½ hours to reach the Burin Peninsula on the south coast of Newfoundland, where 28 people lost their lives in various communities. It also snapped telegraph lines laid under the Atlantic.

[edit] 1933: Showa Sanriku, Japan (??????)

On March 3, 1933, the Sanriku coast of northeastern Honshu, Japan which had already suffered a devastating tsunami in 1896 (see above) was again stuck by tsunami waves as a result of an offshore magnitude 8.1 earthquake. The quake destroyed about 5,000 homes and killed 3,068 people, the vast majority as a result of tsunami waves. Especially hard hit was the coastal village of Taro (now part of Miyako city) in Iwate Prefecture, which lost 42% of its total population and 98% of its buildings. Taro is now protected by an enormous tsunami wall, currently 10 meters in height and over 2 kilometers long. The original wall, constructed in 1958, saved Taro from yet another destruction from the 1960 Chilean tsunami (see below). ja:??????

[edit] 1944: Tonankai, Japan (?????)

A magnitude 8.0 earthquake on 7 December 1944, about 20 km off the Shima Peninsula in Japan, which struck the Pacific coast of central Japan, mainly Mie,Aichi, and Shizuoka Prefectures. News of the event was downplayed by the authorities in order to protect wartime morale, and as a result the full extent of the damage is not known, but the quake is estimated to have killed 1223 people, the tsunami being the leading cause of the fatalities. ja:?????

[edit] 1946: Nankaido, Japan (????)

Main article: 1946 Nankaido earthquake
The Nankai earthquake on 21 December 1946 had a magnitude of 8.4 and hit at 4:19 [local time]. There was a catastrophic earthquake on the southwest of Japan in the Nankai Trough. It was felt almost everywhere in the central and western parts of the country. The tsunami that washed away 1451 houses and caused 1500 deaths in Japan. It was observed on tide gauges in California, Hawaii, and Peru.[11]
The Nankai megathrust earthquakes are periodic earthquakes occurring off the southern coast of Kii Peninsula and Shikoku, Japan every 100 to 150 years. Particularly hard hit were the coastal towns of Kushimoto and Kainan on the Kii Peninsula. The quake led to more than 1400 deaths, tsunami being the leading cause. measuring 8.4.

[edit] 1946: Aleutian Islands

Main article: 1946 Aleutian Islands earthquake
external image 250px-Tsunami_large.jpgexternal image magnify-clip.png
Residents run from an approaching tsunami in Hilo, Hawai’i.
On April 1, 1946, the Aleutian Islands tsunami killed 159 people on Hawaii and five in Alaska (the lighthouse keepers at the Scotch Cap Light in the Aleutians). It resulted in the creation of a tsunami warning system known as the Pacific Tsunami Warning Center (PTWC), established in 1949 for Oceania countries. The tsunami is known as the April Fools Day Tsunami in Hawaii due to people thinking the warnings were an April Fools prank.

[edit] 1950–2000

[edit] 1952: Severo-Kurilsk, Kuril Islands, USSR

Main article: 1952 Severo-Kurilsk tsunami
The November 5, 1952 tsunami killed 2,336 on the Kuril Islands, USSR.

[edit] 1958: Lituya Bay, Alaska, USA

Main article: 1958 Lituya Bay megatsunami
On July 9, 1958, an earthquake caused a megatsunami to reach a height taller than the Empire State Building, measuring over 520 metres (1,706 ft), killing two.

[edit] 1960: Valdivia, Chile

Main article: 1960 Valdivia earthquake
The magnitude-9.5 Great Chilean Earthquake of May 22, 1960 is the strongest earthquake ever recorded. Its epicenter, off the coast of South Central Chile, generated one of the most destructive tsunami of the 20th Century. It also caused a volcanic eruption.
It spread across the entire Pacific Ocean, with waves measuring up to 25 meters high. The first tsunami arrived at Hilo approximately 14.8 hrs after it originated off the coast of South Central Chile. The highest wave at Hilo Bay was measured at around 10.7 m (35 ft). 61 lives were lost allegedly due to people's failure to heed warning sirens.
Almost 22 hours after the quake, the waves hit the ill-fated Sanriku coast of Japan, reaching up to 3 m above high tide, and killed 142 people. Up to 6,000 people died in total worldwide due to the earthquake and tsunami.[21]

[edit] 1963: Vajont Dam, Monte Toc, Italy

Main article: Vajont Dam
external image 220px-La_diga_del_Vajont_vista_da_Longarone_18-8-2005.jpgexternal image magnify-clip.png
The Vajont Dam as seen fromLongarone today, showing approximately the top 60-70 metres of concrete. The 200-250 metre wall of water (megatsunami) that over-topped the dam would have obscured virtually all of the sky in this picture.
The Vajont Dam was completed in 1961 under Monte Toc, 100 km north of Venice, Italy. At 262 metres, it was one of the highest dams in the world. On October 9, 1963 an enormous landslide of about 260 million cubic metres of forest, earth, and rock, fell into the reservoir at up to 110 km per hour (68 mph). The resulting displacement of water caused 50 million cubic metres of water to overtop the dam in a 250-metre high megatsunami wave. The flooding destroyed the villages of Longarone, Pirago, Rivalta, Villanova and Faè, killing 1,450 people. Almost 2,000 people (some sources report 1,909) perished in total.

[edit] 1964: Niigata, Japan (????)

The 1964 Niigata earthquake in Japan killed 28 people, and liquefacted whole apartment buildings. A subsequent tsunami destroyed the port of Niigata city.ja:????

[edit] 1964: Alaska, USA

Main article: 1964 Alaska earthquake
After the magnitude 9.2 Good Friday Earthquake, tsunamis struck Alaska, British Columbia, California, and coastal Pacific Northwest towns, killing 121 people. The waves were up to 100 feet tall, and killed 11 people as far away as Crescent City, California. This happened on March 27, 1964. The incident was covered in Dennis Powers' The Raging Sea: The Powerful Account of the Worst Tsunami in U.S. History (ISBN 0806526823).

[edit] 1976: Moro Gulf, Mindanao, Philippines

On August 16, 1976 at 12:11 A.M., a devastating earthquake of 7.9 hit the island of Mindanao, Philippines. It created a tsunami that devastated more than 700 km of coastline bordering Moro Gulf in the North Celebes Sea. An estimated number of victims for this tragedy left 5,000 dead, 2,200 missing or presumed dead, more than 9,500 injured and a total of 93,500 people were left homeless. It devastated the cities of Cotabato, Pagadian, and Zamboanga, and the and provinces of Basilan, Lanao del Norte, Lanao del Sur, Maguindanao, Sultan Kudarat, Sulu, and Zamboanga del Sur.

[edit] 1979: Tumaco, Colombia

A magnitude 7.9 earthquake occurred on December 12, 1979 at 7:59:4.3 UTC along the Pacific coast of Colombia and Ecuador. The earthquake and the resulting tsunami caused the destruction of at least six fishing villages and the death of hundreds of people in the Colombian Department of Nariño. The earthquake was felt in Bogotá, Cali, Popayán, Buenaventura, and several other cities and towns in Colombia and in Guayaquil, Esmeraldas, Quito, and other parts of Ecuador. When the tsunami hit the coast, it caused huge destruction in the city of Tumaco, as well as in the small towns of El Charco, San Juan, Mosquera, and Salahonda on the Pacific coast of Colombia. The total number of victims of this tragedy was 259 dead, 798 wounded and 95 missing or presumed dead.

[edit] 1980: Spirit Lake, Washington, USA

Main articles: Spirit Lake (Washington), 1980 eruption of Mount St. Helens, and Mount St. Helens
On May 18, 1980, the upper 460m (1400 ft) of Mount St. Helens had failed caused by a major landslide and slid off the rest of the mountain. One lobe of the landslide surged onto the nearby Spirit Lake, creating a megatsunami of 260 meters high.[22]

[edit] 1983: Sea of Japan (???????)

On May 26, 1983 at 11:59:57 local time, a magnitude-7.7 earthquake occurred in the Sea of Japan, about 100 km west of the coast of Noshiro in Akita Prefecture, Japan. Out of the 107 fatalities, all but four were killed by the resulting tsunami, which struck communities along the coast, especially Aomori andAkita Prefectures and the east coast of Noto Peninsula. Footage of the tsunami hitting the fishing harbor of Wajima on Noto Peninsula was broadcast on TV. The waves exceeded 10 meters in some areas. Three of the fatalities were along the east coast of South Korea (whether North Korea was affected is not known). The tsunami also hit Okushiri Island, the site of a more deadly tsunami 10 years later. ja:???????

[edit] 1993: Okushiri, Hokkaido, Japan (????????)

Main article: 1993 Hokkaido earthquake
A devastating tsunami wave occurred along the coasts of Hokkaido in Japan as a result of a magnitude 7.8 earthquake, 80 miles (130 km) offshore, on July 12, 1993.
Within minutes, the Japan Meteorological Agency issued a tsunami warning that was broadcast on NHK in English and Japanese (archived at NHK library). However, it was too late for Okushiri, a small island near the epicenter, which was struck with extremely big waves, some reaching 30 meters, within two to five minutes of the quake. Aonae, a village on a low-lying peninsula at the southern tip of the island, was devastated over the course of the following hour by 13 waves of over two meters’ height arriving from multiple directions, including waves that had bounced back off Hokkaido—despite being surrounded by tsunami barriers. Of 250 people killed as a result of the quake, 197 were victims of the series of tsunamis that hit Okushiri; the waves also caused deaths on the coast of Hokkaido. While many residents, remembering the 1983 tsunami (see above), survived by quickly evacuating on foot to higher ground, it is thought that many others underestimated how soon the waves would arrive (the 1983 tsunami took 17 minutes to hit Okushiri) and were killed as they attempted to evacuate by car along the village’s narrow lanes. The highest wave of the tsunami was a staggering 31 meters (102 ft) high. ja:????????

[edit] 1998: Papua New Guinea

Main article: 1998 Papua New Guinea earthquake
On 17 July 1998, a Papua New Guinea tsunami killed approximately 2,200 people.[23] A 7.1-magnitude earthquake 24 km offshore was followed within 11 minutes by a tsunami about 15 metres tall. The tsunami was generated by an undersea landslide, which was triggered by the earthquake. The magnitude of the earthquake was too low to generate a tsunami. The villages of Arop and Warapu were destroyed.

[edit] 2000s

[edit] 2004: Indian Ocean

Main article: 2004 Indian Ocean earthquake
external image 220px-2004-tsunami.jpgexternal image magnify-clip.png
The 2004 Indian Ocean earthquake; Tsunami strikes Ao Nang, Thailand.
The 2004 Indian Ocean earthquake, which had a moment magnitude of 9.1–9.3,[24] triggered a series of lethal tsunamis on December 26, 2004, that killed approximately 230,210 people (including 168,000 in Indonesia alone), making it the deadliest tsunami as well as one of the deadliest natural disasters in recorded history. It was also caused by the third largest earthquake in recorded history. The initial surge was measured at a height of approximately 33 meters (108 ft), making it the largest earthquake-generated tsunami in recorded history. The tsunami killed people over an area ranging from the immediate vicinity of the quake inIndonesia, Thailand, and the north-western coast of Malaysia, to thousands of kilometres away in Bangladesh, India, Sri Lanka, the Maldives, and even as far away as Somalia, Kenya, and Tanzania in eastern Africa. This trans-Indian Ocean tsunami is an example of a teletsunami, which can travel vast distances across the open ocean. In this case, it is an ocean-wide tsunami.
Unlike in the Pacific Ocean, there was no organized alert service covering the Indian Ocean. This was in part due to the absence of major tsunami events since 1883 (the Krakatoa eruption, which killed 36,000 people). In light of the 2004 Indian Ocean tsunami, UNESCO and other world bodies have called for an international tsunami monitoring system.

[edit] 2006: South of Java Island

Main article: July 2006 Java earthquake
A 7.7 magnitude earthquake rocked the Indian Ocean seabed on July 17, 2006, 200 km south of Pangandaran, a beautiful beach famous to surfers for its perfect waves. This earthquake triggered tsunamis which height varied from 2 meters at Cilacap to 6 meters at Cimerak beach, where it swept away and flattened buildings as far as 400 meters away from the coastline. More than 800 people were reported missing or dead.

[edit] 2006: Kuril Islands

Main article: 2006 Kuril Islands earthquake
On 15 November 2006, a magnitude 8.3 earthquake occurred off the coast near the Kuril Islands. In spite of the quake's large 8.3 magnitude, a relatively small tsunami was generated. The small tsunami was recorded or observed in Japan and at distant locations throughout the Pacific.

[edit] 2007: Solomon Islands

Main article: 2007 Solomon Islands earthquake
On April 24, 2007, a powerful magnitude 8.1 (initially 7.6) earthquake hit the East Pacific region about 25 miles (40 km) northwest of the Solomon Islands at 7:39 a.m., resulting in a tsunami that was up to 17 feet (5 m) tall. The wave, which struck the coast of Solomon Islands (mainly Gizo), triggered region-wide tsunami warnings and watches extending from Japan to New Zealand to Hawaii and the eastern seaboard of Australia. The tsunami that followed the earthquake killed 52 people. Dozens more have been injured with entire towns inundated by the sweeping water which travelled 300 meters inland in some places. Simbo, Choiseul and Ranunga islands were also affected. A state of national emergency was declared for the Solomon Islands. On the island of Choiseul, a wall of water reported to be 30 feet (9.1 m) high swept almost 400 meters inland destroying everything in its path. Officials estimate that the tsunami displaced more than 5000 residents all over the archipelago.

[edit] 2007: Niigata, Japan (????????)

Main article: 2007 Niigata earthquake
On 16 July 2007, a strong earthquake struck northwestern Japan, causing a fire and minor radioactive water leak at one of the world's most powerful nuclear power plants. At least seven people were killed and hundreds injured. Japan's Meteorological Agency measured the quake at 6.8 on the richter scale and sending aftershocks of 6.6. The U.S. Geological Survey, which monitors quakes around the world, said the initial quake registered 6.7. A tsunami watch was issued along the Sea of Japan. The predicted height of the tsunami was estimated to be 50 cm (20 inches).[25] That earthquake sparked only a few small tsunamis, growing to be no more than about 20 cm (8 inches) tall. However, the 1964 quake and tsunami north of the current one destroyed the port of the city of Niigata. ja:????????

[edit] 2010: Chile

external image 220px-Balaustradas_destruidas_y_el_techo_de_un_quiosco_sobre_unas_balaustradas%2C_Pichilemu.jpgexternal image magnify-clip.png
Destruction provoked by the 2010 Chile earthquake and tsunami, inPichilemu, O'Higgins Region, Chile.
Main article: 2010 Chile earthquake
The seismic event in the southern Pacific produced waves measuring 1.8–9 meters along the Sanriku Coastline of northeastern Honshu in Japan.[clarification needed][26]

[edit] 2011: New Zealand

Main article: 2011 Christchurch earthquake
On February 22, 2011, a 6.3 magnitude earthquake hit the Canterbury Region of the South Island, New Zealand. Some 200 kilometres (120 mi) away from the earthquake's epicenter, around 30 million tonnes of ice tumbled off the Tasman Glacier into Tasman Lake, producing a series of 3.5 m (11 ft) high tsunami waves, which hit tourist boats in the lake.[27][28]

[edit] 2011: Pacific coast of Japan

Main article: 2011 Sendai earthquake and tsunami
On March 11, 2011, off the Pacific coast of Japan, a 9.0 magnitude earthquake produced a tsunami 33 feet (10 m) high along Japan's northeastern coast. The wave caused widespread devastation, with 10,000 people thought dead and many thousands more unaccounted for. In addition it precipitated a hydrogen explosion and a suspected partial nuclear meltdown at the Fukushima I Nuclear Power Plant. Tsunami warning were issued to the entire Pacific Rim.[29][30]

[edit] Highest or tallest

Main article: Megatsunami

[edit] Deadliest

The deadliest tsunami in recorded history was the 2004 Asian tsunami, which killed almost 230,000 people in eleven countries across the Indian Ocean.

[edit] Other historic tsunamis

Other tsunamis that have occurred include the following:

      • ca. 500 BC: Poompuhar, Tamil Nadu, India, Maldives
      • 1541: a tsunami struck the earliest European settlement in Brazil, São Vicente. There is no record of deaths or injuries, but the town was almost completely destroyed.

[edit] South Asia

Tsunamis in South Asia
Source: Amateur Seismic Centre, India[31]
Near Dabhol, Maharashtra
2 April 1762
Arakan Coast, Myanmar
16 June 1819
Rann of Kachchh, Gujarat, India
31 October 1847
Great Nicobar Island, India
31 December 1881
Car Nicobar Island, India
26 August 1883
Krakatoa, Sunda Strait, Indonesia
28 November 1945
Mekran coast, Balochistan

[edit] North America and the Caribbean

[edit] Possible

Source: NOAA National Weather Service Forecast Office,[32]

[edit] Europe

      • 6100 BC – Storegga Slide, Norway – The Storegga slide generated a huge tsunami that washed through the North Atlantic Ocean, hitting Norway,Iceland and the east coast of Scotland, where it reached a height of 21 metres, and even washed over some of the Shetland Islands.
      • 11 January 1683 – An earthquake in Italy triggered a tsunami that killed more than 1000 people.
      • 6 February 1783 – An offshore earthquake in Southern Italy caused a tsunami that killed around 1500 people.
      • 20 September 1867 – An earthquake in Greece caused a tsunami that killed 12 people.
      • 11 September 1930 – 2 people were killed by a tsunami in Italy, caused by an undersea earthquake measuring 7.7 on the Richter Scale.
      • 9 July 1956 – An earthquake in Greece generated a tsunami that drowned 4 people.
      • 28 February 1969 – A submarine earthquake measuring 7.3 on the Richter Scale, with its epicentre of the coast of Portugal, caused a tsunami that hitNorthern Portugal, parts of Spain, and Morocco. No lives were lost.
      • 16 October 1979 – 23 people died when the coast of Nice, France, was hit by a tsunami, caused by an undersea landslide. The sea suddenly receded from the shore and returned in two huge waves, hitting a 36-mile-long coastal stretch. Hundreds of boats were overturned, and 11 people working in a shipyard were drowned.
      • 13 December 1990 – 6 people died when an undersea earthquake in Italy caused a tsunami.
      • 17 August 1999 – The 1999 Izmit earthquake in Northwest Turkey triggered a 2 metre high tsunami in the Sea of Marmara.[33][34][35][36]

[edit] Possible

The 1607 Bristol Channel floods, which were traditionally believed to be a massive storm surge, could possibly have been a tsunami, caused by an earthquake or landslide off the coast of Southern Ireland. There is some evidence suggesting it was a tsunami, but not enough to confirm. It was the deadliest natural disaster in the history of the United Kingdom, and killed around 2000 people from Somerset to Cardiff.

[edit] See also

Disasters portal

[edit] References

  1. ^ Thucydides: “A History of the Peloponnesian War”, 3.89.1-5
  2. ^ Smid, T. C.: "'Tsunamis' in Greek Literature", Greece & Rome, 2nd Ser., Vol. 17, No. 1 (Apr., 1970), pp. 100-104 (102f.)
  3. ^ Herodotus: "The Histories", 8.129
  4. ^ Antonopoulos, John: "The Tsunami of 426 BC in the Maliakos Gulf, Eastern Greece", Natural Hazards, Vol. 5 (1992), pp.83-93
  5. ^ Smid, T. C.: "'Tsunamis' in Greek Literature", Greece & Rome, 2nd Ser., Vol. 17, No. 1 (Apr., 1970), pp. 100-104 (103f.)
  6. ^ Paul Kronfield. "The Lost Cities of Ancient Helike: Principal Ancient Sources". Retrieved 2011-03-11.
  7. ^ //**a**// //**b**// Kelly, Gavin: “Ammianus and the Great Tsunami”, The Journal of Roman Studies, Vol. 94 (2004), pp. 141-167 (141)
  8. ^ Stanley, Jean-Daniel & Jorstad, Thomas F. (2005): "The 365 A.D. Tsunami Destruction of Alexandria, Egypt: Erosion, Deformation of Strata and Introduction of Allochthonous Material"
  9. ^ Stiros, Stathis C.: “The A.D. 365 Crete earthquake and possible seismic clustering during the fourth to sixth centuries AD in the Eastern Mediterranean: a review of historical and archaeological data”, Journal of Structural Geology, Vol. 23 (2001), pp. 545-562 (549 & 557)
  10. ^ "Fault found for Mediterranean 'day of horror'." New Scientist magazine, 15 March 2008, p. 16.
  11. ^ //**a**// //**b**// //**c**// //**d**// //**e**// //**f**// //**g**// //**h**// Paula Dunbar (2005-09-20). "JNOAA Earthquake Database Query". Retrieved 2011-03-11.
  12. ^ [1][dead link]
  13. ^ (Earth and Planetary Science Letters, DOI: 10.1016/j.epsl.2008.02.021). In: "Fault found for Mediterranean 'day of horror'." New Scientistmagazine, 15 March 2008, p. 16.
  14. ^ Kamio, Kenji, and Willson, H. An English Guide to Kamakura's Temples and Shrines, pp.143-144.
  15. ^ Ishabashi, K. (1981). "Specification of a soon-to-occur seismic faulting in the Tokai District, central Japan, based on seismotectoncs". In Simpson D.W. & Pichards P.G.. Earthquake prediction: an international review. Maurice Ewing Series. 4. American Geophysical Union. pp. 323-??324.ISBN 9780875904030.
  16. ^ Satake, K. (2007). "Volcanic origin of the 1741 Oshima-Oshima tsunami in the Japan Sea". Earth Planets Space 59: 381–390. Retrieved 7 November 2010.
  17. ^ NGDC. "Comments for the Tsunami Event".,91,95,93&nd=display. Retrieved 7 November 2010.
  18. ^ "???". Retrieved 2011-03-11.
  19. ^ (Japanese) ??????
  20. ^ "The 1868 Arica Tsunami". Retrieved 2011-03-11.
  21. ^ "Emergency & Disasters Data Base". CRED. Retrieved 2006-05-30.
  22. ^
  23. ^ "Tsunamis and Earthquakes – 1998 Papua New Guinea tsunami Descriptive Model – USGS WCMG". Retrieved 2011-03-11.
  24. ^ "USDOC/NOAA/NESDIS/NGDC- Tsunami Information, Dec 26, 2004 Indian Ocean Magnitude 9.0 Earthquake". 2004-12-26. Retrieved 2011-03-11.
  25. ^ "Strong quake jolts Japan, tsunami alert issued". Reuters. Retrieved 2007-07-16.
  26. ^ "Tsunamis up to 1.9 meters hit Sanriku coast after Chile quake," Japan Today. March 6, 2010.
  27. ^ "Ice breaks off glacier after Christchurch quake – ABC News (Australian Broadcasting Corporation)". 2011-02-22. Retrieved 2011-03-11.
  28. ^ "Quake shakes 30m tonnes of ice off glacier – National – NZ Herald News". 2011-02-22. Retrieved 2011-03-11.
  29. ^ "Japan Hit by 33ft Tsunami". Daily Express (London). March 11, 2011. Retrieved 12 March 2011.
  30. ^
  31. ^ ":: ASC :: Tsunamis & Seiches in south Asia". Retrieved 2011-03-11.
  32. ^ "Tsunamis en México :: Investigaciones". esmas. Retrieved 2011-03-11.
  33. ^ "Marine Georesources & Geotechnology".,3,4;journal,18,26;linkingpublicationresults,1:102476,1. Retrieved 2011-03-11.
  34. ^ [2][dead link]
  35. ^
  36. ^ "THE 1979 NICE AIRPORT CATASTROPH REVISITED" (PDF). Retrieved 2011-03-11.

Retrieved from ""
Categories: Tsunamis in Japan | Tsunamis
Hidden categories: All articles with dead external links | Articles with dead external links from March 2011 | All articles with unsourced statements | Articles with unsourced statements from February 2008 | All pages needing cleanup | Wikipedia articles needing clarification from March 2011

Personal tools





    • This page was last modified on 15 March 2011 at 13:23.

Japan shares rebound after slump
The fuel rod exposure at Fukushima Daiichi number 2 reactor is potentially the most serious event so far at the plant.
A local government official confirmed the fuel rods were at one point largely, if not totally exposed; but we do not know for how long.
Without coolant around the rods, temperatures can rise to levels hot enough to melt metallic components over a prolonged period.
This opens the possibility of a serious meltdown – where molten, highly radioactive material from the reactor core falls through the floor of the containment vessel and into the ground underneath.
However, engineers appear to have restored some water flow into the reactor vessel and if they are successful, temperatures will begin to fall again rapidly.
What the incident illustrates is the ad-hoc nature of the operation being mounted at Fukushima.
An official with the Tokyo Electric Power Company (Tepco), which runs the site, said seawater was being pumped in both by fire engines and via the system installed to extinguish fires in the power station's turbine hall.
Continue reading the main story

“Start Quote

  • Meltdown wouldn't be a good scenario, but much better it does that than explodes”

End Quote Paddy Regan Surrey University
He told BBC News that the use of this methodology had never been foreseen – it had been invented by the team on the ground at Fukushima.
Even the mere use of seawater in this way is an extraordinary step to take.
According to the main Japanese news agency Kyodo, the rods were exposed when the flow of seawater into reactor number 2 stopped simply because a fire pump ran out of fuel.
With the entire region of Honshu island reportedly low on fuel and other vital supplies, a key question is whether plans are in place to keep the power station supplied with diesel.
Core issue
With reactor 2, what is not yet known is how long the rods were exposed to the air, and what temperatures were reached.
In the absence of cooling, temperatures in the core could rise up to 2,000C (3,600F), said Paddy Regan, professor of nuclear physics at the UK's University of Surrey – hot enough to melt the zirconium cladding that surrounds the fuel rods.
In addition, the zirconium reacts at these temperatures with water molecules to form hydrogen.
This makes the cladding more brittle and likely to fall away from the rods.
The fuel itself – being in the form of ceramic pellets – should not directly melt, although the hotter it gets the more likely it is that steam can leach out radioactive substances from the pellets.
Boiling water reactor system schematic diagramBoiling water reactor system schematic diagram
A nightmare scenario for any nuclear plant is a total meltdown – where the molten core collapses in the bottom of the steel containment vessel and heats it so much that it falls through.
This possibility was highlighted by the 1979 incident at Three Mile Island in the US – and dramatised in the contemporary movie The China Syndrome.
The steel containment vessel, though, is designed to withstand temperatures substantially higher than 2,000C – so is meltdown a realistic possibility?
"It is possible," Professor Regan told BBC News.
"It didn't happen at Three Mile Island, though.
"If it did happen, it would still be localised; it wouldn't be a good scenario, but much better it does that than explodes."
The key issue for technicians in the plant now is to get enough water into the reactor to bring the temperature down again.
Further releases of mildly radioactive steam from the containment vessel are likely, because the hot core will vaporise much of the water that is injected.
Releasing the steam is also the main way to take heat out of the vessel.
Tepco is reportedly considering making holes in the roof of the reactor 2 building so hydrogen released with the steam will not collect and lead to a third explosion.
Multiple failures
The chain of failures illustrates the capacity of events such as this massive earthquake and tsunami to overwhelm systems that are designed to be "redundant" – to have more than one means of doing the same thing.
Woman in hat and maskWoman in hat and mask Displaced residents of the Fukushima area were taken to evacuation centres
The earthquake caused Fukushima Daiichi and other power stations to shut down – taking away the electricity driving the reactors' cooling systems.
Back-up was supposed to come from diesel generators.
They cut in – but then cut out again after about an hour, probably due to being overwhelmed by water from the tsunami, although Tepco has not confirmed this.
The diesels themselves were backed up further by batteries, but these were designed to function only for eight hours.
When they ran out, nothing else was available.
Reports say that five fire pumps were then deployed to provide water, but that the explosions in buildings 1 and 3 knocked four of them out of action.
Meanwhile, devastation from the tsunami as well as the fear of aftershocks means simply driving new pumps or fuel to the site is much more difficult than it would be under normal circumstances.
All this is already providing material for anti-nuclear groups to argue that no nuclear facility can be designed to be completely safe.
This is manifestly correct; but the same is true for any industrial operation.
Supporters of nuclear power will point to the fact that so far casualties number just a few, that engineers have so far – however desperately – been able to confine the problem, and that far fewer people die each year from nuclear accidents than in coal-mining.

More on This Story

Japan Earthquake





Share this page

More Science & Environment stories


Top Stories

Features & Analysis

  • A mother walks past the Door of Hope orphanage in Berea, central Johannesburg'Baby bin'

    Giving chance of life to South Africa's unwanted infants

  • Three Mile Island plantThree Mile Island

    Lessons from the 1979 nuclear disaster seared into US memory

  • Man on £20 noteFilthy lucre

    Has morality got anything to do with making money?

  • Bob Marley on the beachLost footage

    Reggae star Bob Marley as we've never seen him before

Most Popular


  1. 1: Bob Marley's 'human moment' revealed in lost footage
  2. 2: Japanese emperor 'deeply worried'
  3. 3: 'Radiation' text message is fake
  4. 4: 'Red tape' forces quake team home
  5. 5: Footage of moment tsunami hit Japan


  1. 1: Staff withdrawn from Japan plant
  2. 2: LIVE: Japan earthquake
  3. 3: Japan earthquake: In pictures
  4. 4: 'Radiation' text message is fake
  5. 5: New fire hits Japan nuclear plant
  6. 6: Q&A: Fukushima radiation alert
  7. 7: Two killed in new Bahrain clashes
  8. 8: Lessons from Three Mile Island
  9. 9: Reactor breach worsens prospects
  10. 10: Tsunami could be 1,000-year event


  1. 1: Protesters overrun in Bahrain capital Watch
  2. 2: Tsunami wave sweeps inland Watch
  3. 3: Footage of moment tsunami hit Japan Watch
  4. 4: How the tsunami unfolded Watch
  5. 5: Ofunato rescue team search for bodies Watch
  6. 6: India to 'grow faster than China' Watch
  7. 7: One-minute World News Watch
  8. 8: White vapour billows from nuclear plant Watch
  9. 9: The 'lost' footage of Bob Marley Watch
  10. 10: Japan's emperor 'deeply worried' Watch

Elsewhere on the BBC

  • Athlone, IrelandRelaxing by the river

    BBC Travel joins the bon vivants and boaters on the Shannon in Ireland


  • Thousands of commuters alight from trains enroute to workHARDtalk Watch

    How can the Indian economy grow quicker than China's over the next 10 years?


About BBC News

============================ .A Look at the Mechanics of a Partial MeltdownBy HENRY FOUNTAIN Published: March 13, 2011 Recommend Twitter Sign In to E-Mail Print Reprints Share Close LinkedinDiggMixxMySpacePermalink. The difference between a partial meltdown and a full meltdown at a nuclear plant is enormous, both in the degree of damage and in the potential release of radiation, experts in nuclear power said. Enlarge This Image Kyodo/Reuters One of the two nuclear plants in Fukushima Prefecture in northern Japan where partial meltdowns have taken place. Multimedia Interactive Feature The Crippled Japanese Nuclear Reactors.Related Radioactive Releases in Japan Could Last Months, Experts Say (March 14, 2011) Second Explosion at Reactor as Technicians Try to Contain Damage (March 14, 2011) Military Crew Said to Be Exposed to Radiation, but Officials Call Risk in U.S. Slight (March 14, 2011) Death Toll Estimate in Japan Soars as Relief Efforts Intensify (March 14, 2011) Related in Opinion Room For Debate: Japan's Nuclear Crisis: Lessons for the U.S. A blog about energy and the environment. Go to Blog » .A partial meltdown, like those suspected at two reactors in northeastern Japan over the weekend, may not necessarily mean that any of the uranium fuel in the core has melted, experts said. The fuel rods may be only damaged, a portion of them having been left uncovered by cooling water long enough to crack, allowing the release of some radioactive elements in the fuel. But in a full meltdown — which could occur within hours if all cooling water was lost and the rods became completely uncovered — melting is all but guaranteed, as thousands of fuel pellets fall to the bottom of the reactor and heat themselves into a molten pool at several thousand degrees Fahrenheit. While it is considered highly unlikely that a full meltdown would result in a nuclear chain reaction, experts said, such lava-like fuel might breach the reactor’s pressure vessel and then its containment, leading to widespread release of radioactivity. To avoid such a catastrophe, workers at the two reactors have tried to pump enough seawater into them to keep the cores completely covered. But unless normal cooling systems can be restored, they will have to keep pumping seawater for weeks. “You’re looking at several thousands of gallons a day potentially out as long as a year,” said Arnold Gundersen, a former nuclear engineer who worked on reactors of the same design as those in Japan. The Japanese reactors, made by General Electric and built in the 1970s, have thousands of thin, 12-foot-long fuel rods stacked like straws inside a pressure vessel made of steel up to 6 inches thick. The rods, tubes made of a zirconium alloy, contain ceramic pellets of uranium oxide that are about the size of a fingertip. Ordinarily, this fuel core is kept submerged in water that circulates to remove the heat of nuclear fission, making steam that is used to turn turbines to generate electricity. With loss of power and pumps after the earthquake, the fission reactions at the plants were successfully halted. But there is much residual heat in the reactors, both because they operated at about 550 degrees Fahrenheit and because the radioactive elements in the fuel continue to produce heat as they decay. Without pumps to circulate the water, it will boil off quickly. That apparently is what happened at least one of the reactors, leaving the upper part of the cores uncovered until technicians, in what has been described as a desperate measure, rigged up a way to pump seawater in. The sea water is laced with boric acid, which would quench a fission reaction if one began. Once part of the core is exposed, the zirconium starts to oxidize, or rust, extremely rapidly, becoming brittle and cracking. The rusting also results in the production of explosive hydrogen; the cracking allows the most volatile radioactive elements in the fuel, like iodine and cesium, to escape. To prevent pressure buildup, the gases are allowed to vent into the containment, and in this case must have leaked or were vented through the containment into outside air. As the rods crack apart, the pellets inside them can start to fall out, which engineers call a washout. “There’s nothing holding them there,” said Margaret Harding, a consultant who worked on reactor designs for General Electric for 27 years. But since lower parts of the core are undamaged, the pellets may end up in various places around the reactor, not necessarily in a clump on the floor. “It’s not guaranteed you’re going to have melting,” she said. At the Three Mile Island accident in Pennsylvania in 1979, in which the core was partly uncovered, robotic cameras later determined that melting had occurred. In the Chernobyl accident in 1986, considered the world’s worst, a power surge led to explosions and a reactor fire, sending an enormous plume of radioactive material into the air. If a full meltdown were to occur at one of the Japanese reactors — meaning operators were unable to keep pumping water and the core became completely uncovered — molten fuel would soon pool on the floor of the pressure vessel. “The worst case is that the molten mass leaves the vessel and creates a steam explosion,” Mr. Gunderson said. “That would destroy the containment.” A version of this article appeared in print on March 14, 2011, on page A9 of the New York edition..Sign In to E-Mail Print Reprints .Connect with The New York Times on Facebook. Get Free E-mail Alerts on These Topics Nuclear Energy Accidents and Safety Radiation Japan ============================ UPDATED March 14, 2011 How a Reactor Shuts Down and What Happens in a Meltdown The operating reactors at Fukushima Daiichi power station automatically shut down during the earthquake. But after subsequent cooling failures, two of them went into partial meltdown.

The Aftermath in Japan

Rescuers struggled to reach survivors on Saturday morning as Japan reeled after an earthquake and a tsunami struck in deadly tandem.

external image 13usergen_190.jpg Photographs

Earthquake and Tsunami in Japan: Readers’ Photos asked readers to send photographs from areas affected by the earthquake and tsunami. Here is a selection of images.

external image 13natori_190.jpg Interactive Feature

Satellite Photos of Japan, Before and After the Quake and Tsunami

Compare satellite images of areas of Japan before and after the disaster.

Tegn abonnement på

BioNyt Videnskabens Verden ( er Danmarks ældste populærvidenskabelige tidsskrift for naturvidenskab. Det er det eneste blad af sin art i Danmark, som er helliget international forskning inden for livsvidenskaberne.

Bladet bringer aktuelle, spændende forskningsnyheder inden for biologi, medicin og andre naturvidenskabelige områder som f.eks. klimaændringer, nanoteknologi, partikelfysik, astronomi, seksualitet, biologiske våben, ecstasy, evolutionsbiologi, kloning, fedme, søvnforskning, muligheden for liv på mars, influenzaepidemier, livets opståen osv.

Artiklerne roses for at gøre vanskeligt stof forståeligt, uden at den videnskabelige holdbarhed tabes.

Leave a Reply