Mattie plates slide beneath each other into the
Posted On May 4, 2019
At 2:46 P.M. on March 11, 2011, one
of the most powerful earthquakes ever recorded in history hit northeastern
Japan. An earthquake so powerful it triggered a series of large tsunamis that
destroyed many coastal areas of the country and instigated a major nuclear
accident a power station along the coast. This earthquake was referred to as the
Great Sendai Earthquake.
The Great Sendai Earthquake, also referred to
as the Great T?hoku Earthquake, was a magnitude-9.0 earthquake occurred in
northeastern Japan, off the country’s main island, Honshu (Pletcher). The epicenter,
or the middle of the earthquake, was located 130 kilometers east of the city of
Sendai. The focus happened at a depth of thirty kilometers below the bottom of
the Pacific Ocean (Pletcher). It was felt as far away as Russia, Taiwan, and China
(Pletcher). The natural disaster was preceded by several foreshocks. This
included an event that happened by weeks after the main quake that had a
magnitude-7.2 event that centered roughly forty kilometers away from epicenter.
The disaster took the public by surprise
as few scientists predicted the country would experience an earthquake as large
as that, as the original forecast was a lot smaller and in a different area
(Oskin). However, a decade before, Japanese geologist predicted the large earthquake,
but the warnings went unheeded by officials as it was predicted based on past
events that included earthquakes and tsunamis (Oskin). Although, today, Japanese
scientists are researching these past events to better predict future disasters
However, geologists suggest that the
natural disaster relieved stress that the tectonic plates had collected over
centuries (“In”). Because of this, scientist are predicting that the Faultline is
unlikely to create a large earthquake anytime soon (“In”).
was caused by a rupture of the subduction zone, where plates slide beneath each
other into the hotter later beneath the crust, the mantle (Oskin). This certain
subduction zone was associated with the Japanese Trench, which separates the Eurasian
plate from the Pacific plate (Pletcher). These plates collided and released the
energy that cuild up over centuries of collecting energy from sticking to other
plates (Oskin). This caused these two particular plates to displace water that
sat above it which created a series of highly destructive tsunami waves that
measured approximately over thirty feet tall and reached as far as ten
kilometers inland (Pletcher). Sendai wasn’t the only city affected by the
tsunami waves; other communities, including Kamaisha and Miyako in Iwate;
Ishinomaki, Kensennuma, and Shiogama in Miyagi; and Hitachinaka and Kitaibaraki
in Ibaraki were also devastated (Pletcher).
Tsunami warnings were triggered by
the main quake throughout the Pacific basin (Pletcher). The natural oceanic
disaster raced from the epicenter towards the land at about 800 kilometers per
hour, generating waves that affected many other areas of the world, including
the Hawaiian Islands chain, Aleutian Islands chain, and the west coast of North
America (Pletcher). Eighteen hours after, waves also reached Antarctica and
caused the outer-shell of the Sulzberger Shelf to break (Pletcher).
There was a warning of the seismic
disaster one-minute prior from the Japan early warning system that monitor
stringent seismic building codes to predict when an earthquake is about to
begin (Oskin). This helped save many lives as this one minute warning shut down
many (possible high-casualty) facilities, for example trains (Oskin). Within
two weeks of the disaster, the Japanese government’s official count of death
surpassed 10,000; more than one and a half times that were still listed as missing
and presumed dead (Pletcher). The numbers dramatically increased in the
following days which sprung multiple rescue operations along the Japanese coast
The official count rose to approximately 28,500, but
by the end of 2011, the number reduced to 19,300 (Pletcher). More than half the
victims were age 65 years or older (Pletcher). Out of all the prefectures in
Japan that were in the effected area, Miyagi suffered the greatest of losses as
10,800 were officially pronounced dead or missing and another 4,100 were
all the human casualties were caused by the large tsunami waves along the coast,
the earthquake was responsible for a considerable amount of damage over a wider
area (Pletcher). Fires took place in many cities such as a petrochemical plant
in Sendai, a portion of the city of Kensennuma, and an oil refinery at Ichihara
(Pletcher). Infrastructure throughout
eastern T?hoku was heavily affected with roads and rail lines damaged, water
and sewage systems disrupted, and electric power knocked out (Pletcher). A dam,
near the prefectural capital, Fukushima city, burst due to the earthquake causing
the destruction of thousands of homes in Fukushima, Ibaraki, and Chiba prefectures
The tsunami also caused a considerable amount of
oceanic litter to become a considerable concern among habitants near the
Pacific Ocean. The National Oceanic and Atmospheric Agency reported that the
tsunami carried out five million tons of debris and trash out to the sea
(Oskin). Within weeks following the disaster, much of the debris from the coast
of Japan showed up along the North American west coast (Oskin).
Another result from the natural disaster
included the significant concern of the status of several nuclear power
stations in the T?hoku region (Pletcher). Three nuclear power plants shut down
their reactors at they were closest to the epicenter (Pletcher). The
aftershocks from the earthquake cut the main power and the tsunami waves
damaged the back up generators at some of the plants, most notably the Fukushima
Daiichi plant, also known as “Number One” plant, a plant situated in the northeastern
Fukushima prefecture about 100 kilometers south of Sendai (Pletcher).
With the power gone, the cooling
systems failed and a few days after the disaster, the cores overheated which led
to partial meltdowns of the fuel rods (Pletcher). The melted material fell and
burned sizable holes in the bottom of the containment vessels in reactors one
and two, exposing nuclear materials in the cores (Pletcher). Pressurized hydrogen
gas in the outer containment buildings enclosing the reactors caused multiple
explosions to erupt (Pletcher). Fuel rods stored in reactor four were touched
off by the fire resulting from the explosions in the first three reactors
(Pletcher). The facility released significant levels of radiation in the weeks
following the earthquake; workers sought to stabilize the damaged reactors by
cooling them with seawater and boric acid (Pletcher).
Japanese officials were afraid of possible radiation
exposure, so they established a thirty kilometer no-fly zone and created an
area of twenty kilometers around the Fukushima Daiichi plant (Pletcher). There
was a spike in levels of radiation found in the local food and water supplies
that prompted officials in Japan and overseas to issue warnings about their
consumption (Pletcher). Towards the end of March 2011, seawater near the Daiichi
facility was discovered to have been contaminated with high levels of iodine-131,
cesium-134, and cesium-137, and other radioactive isotopes which stemmed from
the exposure of pumped-in seawater that workers used to cool the fuel coils (Pletcher).
The water later had leaked in water-filled trenches and tunnels between the
facility and the ocean (Pletcher).
Japanese nuclear regulators, in mid-April, elevated
the security level of the nuclear emergency at the Fukushima Daiichi from five
to seven—the highest level on the scale created by the International Atomic
Energy Agency (Pletcher). This placed the Fukushima accident in the same
category as the Chernobyl accident, which happened in the Soviet Union in 1986).
Evaluation zones were thought to be uninhabitable for decades, due to radiation
levels remaining high for many weeks after the accident (Pletcher). However,
several months after the accident, government officials announced radiation
levels in five towns just beyond the twenty kilometer radius had declined
enough to allow residents to reenter their homes, but some former residents stayed
away, concerned about the amount of radiation in the soil (Pletcher).
In December 2011, Japanese Prime Minister Noda
Yoshihiko declared the Fukushima Daiichi facility stable, but numerous leaks
followed the accident (Pletcher). Years later, a significant leak happened in
August 2013, which was severe enough to prompt Japan’s Nuclear Regulation
Authority to classify it as a level-3 nuclear incident (Pletcher).
In the first hours of the earthquake,
the Japanese Prime Minister Kan Naoto moved to set up an emergency command
center to be located in Tokoyo (Pletcher). In result, many rescue workers and approximately
100,000 members of the Japanese Self-Defense Force were mobilized quickly to
deal with the disaster (Pletcher). Many Japanese citizens criticized Japan’s meteorological
Agency for underestimating the size of the tsunami wave (Oskin). Japanese
officials upgraded and installed a new tsunami warning system because of the
However, the warnings the system
issued were unheeded by citizens as people underestimated their personal risk,
assuming that the tsunami wouldn’t reach their area (Oskin). In a study done
over the Miyagi and Fukushima prefectures, officials found that only 58% of
people headed for higher ground after the earthquake (Oskin).
The country also requested U.S.
military personnel stationed in the country to be a part of the relief efforts,
and in turn a U.S. Navy aircraft was dispatched to the area (Pletcher). Several
other countries, such as Australia, China, Indian, New Zealand, South Korea,
and U.S., helped by sending teams for search-and-rescue, while dozens of other
countries and major international relief organizations helped with financial
and material support (Pletcher). Private and other nongovernmental
organizations from all over the world established relief funds to aid in the
rescue and recovery efforts (Pletcher). Scientists, from all over the world,
also swarmed the country to study the Faultline that caused the earthquake
(Oskin). They dropped sensors in the ocean, along the Faultline to measure the
forces that caused the seismic disaster (Oskin).
Initially, the rescue work was
essentially difficult as it was hard to get personnel, supplies, and equipment
to the devastation zone, and periods of inclement weather hindered with air
operations (Pletcher). Once workers did reach the devastation zone, they dealt
with the widespread area of destruction of entire cities that were washed away
or covered by great piles of mud and debris (Pletcher). Even though many people
were rescued in the first several days of the natural disaster, much of the
relief work consisted of the recovery of bodies (Pletcher). Hundreds of bodies
were washed ashore in several areas after they had been swept out towards to the
open sea (Pletcher).
Shelters were limited in their food
and supplies as several hundred-thousand people swept into them, while tens and
thousands more remained isolated in worse conditions, waiting for relief
efforts to reach them (Pletcher). These numbers only grew with the Fukushima
Two weeks after the earthquake, a
quarter million survivors were housed in relief shelters (Pletcher). Over two
years later, a small number remains housed in shelters as the effects of the
land were devastating (Pletcher). More than 300,000 residents were displaced
and lived in temporary homes, such as hotels, public housing units, or private
homes (Pletcher). Four years later, 230,000 people were still displaced,
however a large number was due to the continuation of the Fukushima accident
The country worked to repair the
infrastructure of public services and wouldn’t stop until they were fully
operational again (Pletcher). The region’s power supply continued to be
affected with the ongoing nuclear accident in Fukushima, which caused many temporary
power outages and rolling blackouts (Pletcher).
The economy also took a hit in the
months following the disaster as it caused a severe reduction in the region’s
manufacturing output (Pletcher). The earthquake and tsunami combined caused
damage and loss of business and factories, but by late summer, the economy
repaired itself and grew briskly (Pletcher). In early 2012, industrial output reached
the level it was before the disaster (Pletcher).
The government sought to push supplement
budgets through the legislature, managing to push three different ones through
(Pletcher). In early November, the largest budget, the third one, was approved
and provided roughly $155 billion (Pletcher). A bulk of the money raised for
relief efforts went towards the reconstruction of the devastated areas (Pletcher).
In February 2012, the government also
established a cabinet-level reconstruction agency to help coordinate efforts in
the coastal area (Pletcher). The government planned for the agency to last the
projected estimate it would take the Japanese northeastern coast to be repaired;
the estimate was roughly ten years (Pletcher).The agency worked to attempt to
determine if the buildings they rebuild could be made to withstand earthquakes
and tsunamis (Oskin). In late 2015, the agency reported that the disaster was
almost cleaned up as nearly all the debris from each devastated area has been
“In Japan, small shakes presage big
quakes.” Nature News, Nature
Publishing Group, www.nature.com/news/in-japan-small-shakes-presage-big-quakes-1.19252.
Oskin, Becky. “Japan Earthquake & Tsunami of 2011:
Facts and Information.” LiveScience,
Purch, 13 Sept. 2017, www.livescience.com/39110-japan-2011-earthquake-tsunami-facts.html.
Pletcher, Kenneth, and John P.
Rafferty. “Japan earthquake and tsunami of 2011.” Encyclopœdia Britannica, Encyclopœdia Britannica, inc. 22 Nov.