User talk:Dineshstar

Geology

Map of the Tōhoku earthquake and aftershocks on March 11–14 This earthquake occurred where the Pacific Plate is subducting under the plate beneath northern Honshu; which plate is a matter of debate amongst scientists.[27][39] The Pacific plate, which moves at a rate of 8 to 9 cm (3.1 to 3.5 in) per year, dips under Honshu's underlying plate releasing large amounts of energy. This motion pulls the upper plate down until the stress builds up enough to cause a seismic event. The break caused the sea floor to rise by several meters.[39] A quake of this magnitude usually has a rupture length of at least 480 km (300 mi) and generally requires a long, relatively straight fault surface. Because the plate boundary and subduction zone in the area of the rupture is not very straight, it is unusual for the magnitude of an earthquake to exceed 8.5; the magnitude of this earthquake was a surprise to some seismologists.[40] The hypocentral region of this earthquake extended from offshore Iwate Prefecture to offshore Ibaraki Prefecture.[41] The Japanese Meteorological Agency said that the earthquake may have ruptured the fault zone from Iwate to Ibaraki with a length of 500 km (310 mi) and a width of 200 km (120 mi).[42][43] Analysis showed that this earthquake consisted of a set of three events.[44] The earthquake may have had a mechanism similar to that of another large earthquake in 869 with an estimated surface wave magnitude (Ms) of 8.6, which also created a large tsunami.[45] Other major earthquakes with tsunamis struck the Sanriku Coast region in 1896 and in 1933. The strong ground motion registered at the maximum of 7 on the Japan Meteorological Agency seismic intensity scale in Kurihara, Miyagi Prefecture.[46] Three other prefectures—Fukushima, Ibaraki and Tochigi—recorded an upper 6 on the JMA scale. Seismic stations in Iwate, Gunma, Saitama and Chiba Prefecture measured a lower 6, recording an upper 5 in Tokyo. In Russia, the main shock could be felt in Yuzhno-Sakhalinsk (MSK 4) and Kurilsk (MSK 4). The aftershock at 06:25 UTC could be felt in Yuzhno-Kurilsk (MSK 5) and Kurilsk (MSK 4).[47] [edit]Energy

Damage to Tokyo Tower This earthquake released a surface energy (Me) of 1.9±0.5×1017 joules,[48] dissipated as shaking and tsunamic energy, which is nearly double that of the 9.1-magnitude 2004 Indian Ocean earthquake and tsunami that killed 230,000 people. "If we could only harness the [surface] energy from this earthquake, it would power [a] city the size of Los Angeles for an entire year," McNutt said in an interview.[33] The total energy released, also known as the seismic moment (M0), was more than 200,000 times the surface energy and was calculated by the USGS at 3.9×1022 joules,[49] slightly less than the 2004 Indian Ocean quake. This is equivalent to 9,320 gigatons of TNT, or approximately 600 million times the energy of the Hiroshima bomb. Japan's National Research Institute for Earth Science and Disaster Prevention (NIED) calculated a peak ground acceleration of 2.99 g (29.33 m/s²).[50][fn 2] The largest individual recording in Japan was 2.7g, in the Miyagi Prefecture, 75 km from the epicentre; the highest reading in the Tokyo metropolitan area was 0.16g.[53] [edit]Geophysical impacts The quake moved portions of northeastern Japan by as much as 2.4 m (7.9 ft) closer to North America,[26][27] making portions of Japan's landmass wider than before.[27] Portions of Japan closest to the epicenter experienced the largest shifts.[27] A 400 km (250 mi) stretch of coastline dropped vertically by 0.6 m (2.0 ft), allowing the tsunami to travel farther and faster onto land.[27] One early estimate suggested that the Pacific plate may have moved westward by up to 20 m (66 ft),[54] and another early estimate put the amount of slippage at as much as 40 m (130 ft).[55] On 6 April the Japanese coast guard said that the quake shifted the seabed near the epicenter 24 meters (79 ft) and elevated the seabed off the coast of Miyagi prefecture by 3 meters.[56]

Soil liquefaction in Koto, Tokyo The earthquake shifted the Earth's axis by estimates of between 10 cm (4 in) and 25 cm (10 in).[26][27][28] This deviation led to a number of small planetary changes, including the length of a day and the tilt of the Earth.[28] The speed of the Earth's rotation increased, shortening the day by 1.8 microseconds due to the redistribution of Earth's mass.[57] The axial shift was caused by the redistribution of mass on the Earth's surface, which changed the planet's moment of inertia. Because of conservation of angular momentum, such changes of inertia result in small changes to the Earth's rate of rotation.[58] These are expected changes[28] for an earthquake of this magnitude.[26][57] Soil liquefaction was evident in areas of reclaimed land around Tokyo, particularly in Urayasu,[59] Chiba City, Funabashi, Narashino (all in Chiba Prefecture) and in the Koto, Edogawa, Minato, Chūō, and Ōta Wards of Tokyo. Approximately 30 homes or buildings were destroyed and 1,046 other buildings were damaged to varying degrees.[60] Nearby Haneda Airport, built mostly on reclaimed land, was not damaged. Odaiba also experienced liquefaction, but damage was minimal.[61] Shinmoedake, a volcano in Kyushu, erupted two days after the earthquake. The volcano had previously erupted in January 2011; it is not known if the later eruption was linked to the earthquake.[62] In Antarctica, the seismic waves from the earthquake were reported to have caused the Whillans Ice Stream to slip by about 0.5 m (1.6 ft).[63]

Map based on the earthquake's Japan Meteorological Agency seismic intensity scale The first sign international researchers had that the earthquake caused such a dramatic change in the Earth’s rotation came from the United States Geographical Survey which monitors Global Positioning Satellite stations across the world. The Survey team had several GPS monitors located near the scene of the earthquake, and one was directly in the epicenter. The GPS station located in the epicenter proved that Japan had gotten at least thirteen feet wider as a result of the splitting of the Earth. This motivated government researchers to look into other ways the earthquake may have had large scale effects on the planet. Scientists at NASA’s Jet Propulsion Laboratory did some calculations and determined that the Earth’s rotation was changed by the earthquake to the point where the days are now one point eight (1.8) microseconds shorter. [64] While the 1.8 microsecond shortening of the day is not noticeable to the average person, one way the earthquake and its effects on the Earth’s rotation and time of day is important was explained by Dr. Richard Gross, one of the head researchers working for NASA. Gross explained that even a difference of 1.8 microseconds is important to his team, because it affects the way that spacecraft being sent to Mars are navigated. Not taking the changes into account creates a greater chance for failure of the mission, resulting in millions of dollars wasted. Gross noted that the way the Earth rotates is not very smooth; he related the way the Earth moves to an old car wobbling on its axle. The earthquake was similar to if a person took a hammer and whacked the car's axle, causing it to shift and the car to drive differently. This is what occurred with the earthquake in Japan. The powerful earthquake was the hammer hitting the Earth’s axle, causing it to spin in a slightly different way.[65] [edit]Aftershocks Further information: List of foreshocks and aftershocks of the 2011 Tōhoku earthquake Japan experienced over 900 aftershocks since the earthquake, with about 60 registering over magnitude 6.0 Mw and at least three over 7.0 Mw. A magnitude 7.7 Mw and a 7.9 Mw quake occurred on March 11[66] and the third one struck offshore on 7 April with a disputed magnitude. Its epicenter was underwater, 66 km (41 mi) off the coast of Sendai. The Japan Meteorological Agency assigned a magnitude of 7.4 MJMA, while the U.S. Geological Survey lowered it to 7.1 Mw.[67] At least four people were killed, and electricity was cut off across much of northern Japan including the loss of external power to Higashidori Nuclear Power Plant and Rokkasho Reprocessing Plant.[68][69][70] Four days later on April 11, another strong magnitude 6.6 Mw aftershock struck Fukushima, causing additional damage and killing a total of three people.[71][72] As of 3 June 2011 aftershocks continued; a regularly updated map showing all shocks of magnitude 4.5 and above near or off the east coast of Honshu in the last seven days[73] showed over 20 events. By 8 June shocks in the past week had dropped to 13. [edit]Tsunami

Energy map of the tsunami from NOAA The earthquake which was caused by 5 to 8 meters upthrust on a 180-km wide seabed at 60 km offshore from the east coast of Tōhoku[74] resulted in a major tsunami which brought destruction along the Pacific coastline of Japan's northern islands and resulted in the loss of thousands of lives and devastated entire towns. The tsunami propagated across the Pacific, and warnings were issued and evacuations carried out. In many countries bordering the Pacific, including the entire Pacific coast of North and South America from Alaska to Chile;[75][76][77] however, while the tsunami was felt in many of these places, it caused only relatively minor effects. Chile's section of Pacific coast is one of the furthest from Japan, at about 17,000 km (11,000 mi) away,[78] but still was struck by tsunami waves 2 m (6.6 ft) high.[79][80] A wave height of 38.9 meters (128 ft) was estimated at Omoe peninsula, Miyako city, Iwate prefecture.[13] [edit]Japan The tsunami warning issued by the Japan Meteorological Agency was the most serious on its warning scale; it rated as a "major tsunami", being at least 3 m (9.8 ft) high.[81] The actual height predicted varied, the greatest being for Miyagi at 6 m (20 ft) high.[82] The tsunami inundated a total area of approximately 561 km2 (217 sq mi) in Japan.[83]

Water column height on 11 March 2011 at DART Station, 690 NM Southeast of Tokyo The earthquake took place at 14:46 JST around 67 km (42 mi) from the nearest point on Japan's coastline, and initial estimates indicated the tsunami would have taken 10 to 30 minutes to reach the areas first affected, and then areas farther north and south based on the geography of the coastline.[84][85] Just over an hour after the earthquake at 15:55 JST, a tsunami was observed flooding Sendai Airport, which is located near the coast of Miyagi Prefecture,[86][87] with waves sweeping away cars and planes and flooding various buildings as they traveled inland.[88][89] The image of the tsunami sweeping cars on the street in Sendai was caught by an in-car camera. The impact of the tsunami in and around Sendai Airport was filmed by an NHK News helicopter, showing a number of vehicles on local roads trying to escape the approaching wave and being engulfed by it.[90] A 4 m high tsunami hit Iwate Prefecture.[91] Wakabayashi Ward in Sendai was also particularly hard hit.[92] At least 101 designated tsunami evacuation sites were hit by the wave.[93] Like the 2004 Indian Ocean earthquake and tsunami, the damage by surging water, though much more localized, was far more deadly and destructive than the actual quake. There were reports of entire towns destroyed from tsunami-hit areas in Japan, including 9,500 missing in Minamisanriku;[94] one thousand bodies had been recovered in the town by 14 March 2011.[95] Among several factors causing the high death toll from the tsunami, one was the unexpectedly large size of the water surge. The tsunami walls at several of the affected cities were based on much smaller tsunami heights. Also, many people caught in the tsunami thought that they were located on high enough ground to be safe.[96]

Tsunami flooding on the Sendai Airport runway Large parts of Kuji and the southern section of Ōfunato including the port area were almost entirely destroyed[97][98] Also largely destroyed was Rikuzentakata, where the tsunami was reportedly three stories high.[99][100][101] Other cities reportedly destroyed or heavily damaged by the tsunami include Kamaishi, Miyako, Ōtsuchi, and Yamada (in Iwate Prefecture), Namie, Sōma and Minamisōma (in Fukushima Prefecture) and Shichigahama, Higashimatsushima, Onagawa, Natori, Ishinomaki, and Kesennuma (in Miyagi Prefecture).[102][103][104][105][106][107][108] The most severe effects of the tsunami were felt along a 670-km (420 mi)-long stretch of coastline from Erimo in the north to Ōarai in the south, with most of the destruction in that area occurring in the hour following the earthquake.[109] Near Ōarai, people captured images of a huge whirlpool that had been generated by the tsunami.[110] The tsunami washed away the sole bridge to Miyatojima, Miyagi, isolating the island's 900 residents.[111] A two meter high tsunami hit Chiba Prefecture about 2 1/2 hours after the quake, causing heavy damage to cities such as Asahi.[112] On 13 March 2011, the Japan Meteorological Agency (JMA) published details of tsunami observations recorded around the coastline of Japan following the earthquake. These observations included tsunami maximum readings of over 3 m (9.8 ft) at the following locations and times on 11 March 2011, following the earthquake at 14:46 JST:[113] 15:12 JST – off Kamaishi – 6.8 m (22 ft) 15:15 JST – Ōfunato – 3.2 m (10 ft) or higher 15:20 JST – Ishinomaki-shi Ayukawa – 3.3 m (11 ft) or higher 15:21 JST – Miyako – 4.0 m (13.1 ft) or higher 15:21 JST – Kamaishi – 4.1 m (13 ft) or higher 15:44 JST – Erimo-cho Shoya – 3.5 m (11 ft) 15:50 JST – Sōma – 7.3 m (24 ft) or higher 16:52 JST – Ōarai – 4.2 m (14 ft) These readings were obtained from recording stations maintained by the JMA around the coastline of Japan. Many areas were also affected by waves of 1 to 3 meters (3.3 to 9.8 ft) in height, and the JMA bulletin also included the caveat that "At some parts of the coasts, tsunamis may be higher than those observed at the observation sites." The timing of the earliest recorded tsunami maximum readings ranged from 15:12 to 15:21, between 26 and 35 minutes after the earthquake had struck. The bulletin also included initial tsunami observation details, as well as more detailed maps for the coastlines affected by the tsunami waves.[114][115] On 23 March 2011, Port and Airport Research Institute reported tsunami height by visiting the port sites or by telemetry from offshore as follows:[116][117]

NOAA animation of the tsunami's propagation Port of Hachinohe – 5–6 m (16–19 ft) Port of Hachinohe area – 8–9 m (26–29 ft) Port of Kuji – 8–9 m (26–29 ft) Mooring GPS wave height meter at offshore of central Iwate (Miyako) – 6 m (20 ft) Port of Kamaishi – 7–9 m (23–30 ft) Mooring GPS wave height meter at offshore of southern Iwate (Kamaishi) – 6.5 m (22 ft) Port of Ōfunato – 9.5 m (31 ft) Run up height, port of Ōfunato area – 24 m (79 ft) Mooring GPS wave height meter at offshore of northern Miyagi – 5.6 m (18 ft) Fishery port of Onagawa – 15 m (50 ft) Port of Ishinomaki – 5 m (16 ft) Mooring GPS wave height meter at offshore of central Miyagi – could not measure Shiogama section of Shiogama-Sendai port – 4 m (13 ft) Sendai section of Shiogama-Sendai port – 8 m (26 ft) Sendai Airport area – 12 m (39 ft) A joint research team from Yokohama National University and the University of Tokyo also reported that the tsunami at Ryōri Bay (綾里白浜), Ōfunato was about 30 m high. They found fishing equipment scattered on the high cliff above the bay.[118] At Tarō, Iwate, a University of Tokyo researcher reported an estimated tsunami height of 37.9 m (124 ft) reached the slope of a mountain some 200 m (656 ft) away from the coastline.[119] Also, at slope of nearby mountain from 400 m (1,312 ft) Aneyoshi fishery port (姉吉漁港) of Omoe peninsula (重茂半島) in Miyako, Iwate, Tokyo University of Marine Science and Technology found estimated tsunami run up height of 38.9 m (127 ft).[13] This height is deemed the record in Japan historically, as of reporting date, that exceeds 38.2 m (125 ft) from the 1896 Meiji-Sanriku earthquake.[120] [edit]Elsewhere across the Pacific

A Bonin Petrel trapped in the sand on Midway Atoll by the tsunami, before being rescued Shortly after the earthquake, the Pacific Tsunami Warning Center (PTWC) in Hawaii issued tsunami watches and announcements for locations in the Pacific. At 07:30 UTC, PTWC issued a widespread tsunami warning covering the entire Pacific Ocean.[121][122] Russia evacuated 11,000 residents from coastal areas of the Kuril Islands.[123] The United States West Coast and Alaska Tsunami Warning Center issued a tsunami warning for the coastal areas of most of California, all of Oregon, and the western part of Alaska, and a tsunami advisory covering the Pacific coastlines of most of Alaska, and all of Washington and British Columbia, Canada.[124][125] In California and Oregon, up to 2.4 m (8 ft) high tsunami surges hit some areas, damaging docks and harbors and causing over US$10 million in damage.[126] Surges of up to 1 m (3.3 ft) hit Vancouver Island in Canada[125] prompting some evacuations, and causing boats to be banned from the waters surrounding the island for 12 hours following the wave strike, leaving many island residents in the area without means of getting to work.[127][128]

Fishing boats moved to higher ground in anticipation of tsunami arrival, in Pichilemu, Chile In the Philippines, waves up to 0.5 m (1.6 ft) high hit the eastern seaboard of the country. Some houses along the coast in Jayapura, Indonesia were destroyed.[129] Authorities in Wewak, East Sepik, Papua New Guinea evacuated 100 patients from the city's Boram Hospital before it was hit by the waves, causing an estimated US$4 million in damages.[130] Hawaii estimated damage to public infrastructure alone at US$3 million, with damage to private properties, including resort hotels such as Four Seasons Resort Hualalai, estimated at tens of millions of dollars.[131] It was reported that a 1.5 m (5 ft) high wave completely submerged Midway Atoll's reef inlets and Spit Island, killing more than 110,000 nesting seabirds at the Midway Atoll National Wildlife Refuge.[132] Some other South Pacific countries, including Tonga and New Zealand, and U.S. territories American Samoa and Guam, experienced larger-than-normal waves, but did not report any major damage.[133] However in Guam some roads were closed off and people were evacuated from low-lying areas.[134] In Curry County, Oregon $7 million in damages occurred including the destruction of 3,600 feet of dockspace at the Brookings harbor; the county has received over $1 million in FEMA emergency grants.[135] Along the Pacific Coast of Mexico and South America, tsunami surges were reported, but in most places caused little or no damage.[136] Peru reported a wave of 1.5 m (5 ft) and more than 300 homes damaged.[136] The surge in Chile was large enough to damage more than 200 houses,[137] with waves of up to 3 m (9.8 ft).[138][139] In the Galapagos Islands, 260 families received assistance following a 3 m (9.8 ft) surge which arrived 20 hours after the earthquake, after the tsunami warning had been lifted.[140][141] There was a great deal of damage to buildings on the islands and one man was injured but there were no reported fatalities.[142][143] [edit]Land subsidence

Land subsidence and soil liquefaction near Shin-Urayasu Station elevator shaft Geospatial Information Authority of Japan reported land subsidence on the height of triangulation station measured by GPS from previous value on 14 April 2011.[144] Miyako, Iwate - 0.50 m (1.64 ft) Yamada, Iwate - 0.53 m (1.73 ft) Ōtsuchi, Iwate - 0.35 m (1.14 ft)[145] Kamaishi, Iwate - 0.66 m (2.16 ft) Ōfunato, Iwate - 0.73 m (2.39 ft) Rikuzentakata, Iwate - 0.84 m (2.75 ft) Kesennuma, Miyagi - 0.74 m (2.42 ft) Minamisanriku, Miyagi - 0.69 m (2.26 ft) Oshika Peninsula, Miyagi - 1.2 m (3.93 ft)[145] Ishinomaki, Miyagi - 0.78 m (2.55 ft) Higashimatsushima, Miyagi - 0.43 m (1.41 ft) Iwanuma, Miyagi - 0.47 m (1.54 ft) Sōma, Fukushima - 0.29 m (0.95 ft) Scientists say that the subsidence is permanent. As a result, the communities in question are now more susceptible to flooding during high tides.[146] [edit]Casualties

This section is outdated. Please update this section to reflect recent events or newly available information. Please see the talk page for more information. (May 2011)

Memorials amongst the ruins, Natori The National Police Agency has confirmed 15,538 deaths,[4][5] 5,685 injured,[4][5] and 7,060 people missing[4][5] across eighteen prefectures.[4][5] Of the 13,135 fatalities recovered by 11 April 2011, 12,143 or 92.5% died by drowning. Victims aged 60 or older accounted for 65.2% of the deaths, with 24% of total victims being in their 70s.[147]

Tsunami damage between Sendai and Sendai Bay. Save the Children reports that as many as 100,000 children were uprooted from their homes, some of whom were separated from their families because the earthquake occurred during the school day.[148] As of 10 April 2011, Japan's Ministry of Health, Labour and Welfare stated that it was aware of at least 82 children who had been orphaned by the disaster.[149] The quake and tsunami, as of 28 April 2011, killed 378 elementary, middle-school, and high school students and left 158 others missing.[150] One elementary school in Ishinomaki, Miyagi, Okawa Elementary, lost 74 of 108 students and 10 of 13 teachers and staff.[151][152][153] The Japanese Foreign Ministry has confirmed the deaths of nineteen foreigners.[154] Among them are two English teachers from the United States affiliated with the Japan Exchange and Teaching Program;[155] a Canadian missionary in Shiogama;[156] and citizens of China, North and South Korea, Taiwan, Pakistan and the Philippines. By 9:30 UTC on 11 March, Google Person Finder, which was previously used in the Haitian, Chilean, and Christchurch, New Zealand earthquakes, was collecting information about survivors and their locations.[157][158] The Next of Kin Registry (NOKR) is assisting the Japanese government in locating next of kin for those missing or deceased.[159] Japanese funerals are normally elaborate Buddhist ceremonies which entail cremation. The thousands of bodies, however, exceeded the capacity of available crematoriums and morgues, many of them damaged,[160][161] and there were shortages of both kerosene—each cremation requires 50 liters—and dry ice for preservation.[162] The single crematorium in Higashimatsushima, for example, could only handle four bodies a day, although hundreds were found there.[163] Governments and the military were forced to bury many bodies in hastily dug mass graves with rudimentary or no rites, although relatives of the deceased were promised that they would be cremated later.[164] The tsunami is reported to have caused several deaths outside of Japan. One man was killed in Jayapura, Papua, Indonesia after being swept out to sea.[165] A man who is said to have been attempting to photograph the oncoming tsunami at the mouth of the Klamath River, south of Crescent City, California, was swept out to sea.[166][167][168] His body was found on April 2 along Ocean Beach in Fort Stevens State Park, Oregon, some 330 miles (530 km) to the north.[169][170] As of 27 May 2011, three Japan Ground Self-Defense Force members had died while conducting relief operations in Tōhoku.[171] [edit]Damage and effects

Panorama of Rikuzentakata area swept away The degree and extent of damage caused by the earthquake and resulting tsunami were enormous, with most of the damage being caused by the tsunami. Video footage of the towns that were worst affected shows little more than piles of rubble, with almost no parts of any structures left standing.[172] Estimates of the cost of the damage range well into the tens of billions of US dollars; before-and-after satellite photographs of devastated regions show immense damage to many regions.[173][174] Although Japan has invested the equivalent of billions of dollars on anti-tsunami seawalls which line at least 40% of its 34,751 km (21,593 mi) coastline and stand up to 12 m (39 ft) high, the tsunami simply washed over the top of some seawalls, collapsing some in the process.[175] Japan's National Police Agency said on 3 April 2011, that 45,700 buildings were destroyed and 144,300 were damaged by the quake and tsunami. The damaged buildings included 29,500 structures in Miyagi Prefecture, 12,500 in Iwate Prefecture and 2,400 in Fukushima Prefecture.[176] Three hundred hospitals with 20 beds or more in Tōhoku were damaged by the disaster, with 11 being completely destroyed.[177] The earthquake and tsunami created an estimated 24-25 million tons of rubble and debris in Japan.[178][179] An estimated 230,000 automobiles and trucks were damaged or destroyed in the disaster. As of the end of May 2011, residents of Iwate, Miyagi, and Fukushima prefectures had requested deregistration of 15,000 vehicles, meaning that the owners of those vehicles were writing them off as unrepairable or unsalvageable