JAPAN EARTHQUAKRBy Gaurav Baviskar

Earthquake Map

Introduction

It occurred in 2011 off the pacific coast of tohoku.

With a Magnitude of 9.0 (Mw) undersea megathrust earthquake off the coast of Japan that occurred at 14:46 JST on Friday 11 March 2011

The epicentre approximately 70 kilometers (43 mi) east of the OshikaPeninsula of Tohoku and the hypocenter at an underwater depth of approximately 30 km (19 mi)

It was the most powerful known

earthquake ever to have hit Japan,

and the fifth most powerful

earthquake in the world since

modern record-keeping began in

1900.

A Japanese National Police Agency

report confirmed 15,883 deaths,

6,150 injured, and 2,643 people

missing.

As well as 129,225 buildings totally

collapsed, with a further 254,204

buildings 'half collapsed', and

Geology

This earthquake occurred where the

Pacific Plate is subducting under the plate

beneath northern Honshu.

The pacific plate dips under Honshu's

underlying plate building large amounts of

elastic energy.

This motion pushes the upper plate down

until the accumulated stress causes a

seismic slip-rupture event.

It was the convergence of these two

plates over many hundreds of years

that set the stage for the sudden

magnitude 9 earthquake of March 11,

2011

Because the plate boundary and subduction zone in the area of the Honshu rupture is not very straight, it is unusual for the magnitude of its earthquake to exceed 8.5.

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).

This earthquake released a surface energy (Me) of 1.9 ± 0.5×1017 joules, dissipated as shaking and tsunamic energy, which is nearly double that of the 9.1-magnitude 2004 Indian Ocean earthquake and tsunami!!

Seismic intensity map

Geophysical effectsPortions of northeastern Japan shifted by as much as 2.4 m (7.9 ft) closer to North America.

A 400 km stretch of coastline dropped vertically by 0.6 m (2.0 ft), allowing the tsunami to travel farther and faster onto land.

The Earth's axis shifted,thisdeviation led to a number of small planetary changes, including the length of a day, the tilt of the Earth

The speed of the Earth's rotation increased,

shortening the day by 1.8 microseconds due

to the redistribution of Earth's mass.

Soil liquefaction was evident in areas of

reclaimed land around Tokyo, particularly in

Urayasu.

Shinmoedake, a volcano in Kyushu, erupted

three days after the earthquake.

Japan has experienced over 1000 aftershocks

since the earthquake, with 80 registering over

magnitude 6.0 Mw and several of which have

been over magnitude 7.0 Mw.

Pictures 1)Results of

earthquake

2) Before and after

Image

Casualties

The National Police Agency has

confirmed 15,883 deaths, 6,150

injured,and 2,643 people missing across

twenty prefectures.

Of the 13,135 fatalities recovered by 11

April 2011, 12,143 or 92.5% died by

drowning.

Of the total confirmed victims, 14,308

drowned, 667 were crushed to death or

died from internal injuries, and 145

perished from burns.

Damage and effects

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.

An estimated 230,000 automobiles and

trucks were damaged or destroyed in the

disaster.

In the immediate aftermath of the calamity,

at least 1.5 million households were

reported to have lost access to water

supplies.

Ship left atop

building in Otsuchi,

Iwate prefecture,

Japan, following

March 11 Tohoku

earthquake and

tsunami

Houses are

destroyed by

tsunami floods

following the Tohoku

Earthquake in near

Iwaki town,

Widespread destruction of houses and property in the

aftermath of the Great Japan Earthquake and tsunami.

RefrenceWikipedia

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