2008 年

中国・四川大地震http://earthquake.usgs.gov/eqcenter/eqinthenews/2008/us2008ryan/#details

被害概要

震源地：　アバ・チベット族チャン族自治州の●川（ぶんせん）県

同県で７７００人が死亡した可能性がある

5 月 14 日現在の確認された死者：四川省で１万２０１２人、甘粛省で２０６人、陝西省で１０３人、重慶市で１１人など。負傷者：　２万９２７８人。

地震情報

Magnitude: 7.9

Date-Time: Monday, May 12, 2008 at 02:28:01 PM at epicenter

Depth: 10 km

震源図

Focal Machanism

震源付近の余震から想定できる逆断

層

地震災害マップ

加速度で表現した震度

Figure 4. Surface projection of the slip distribution superimposed on ETOPO2. The black line indicates the major plate boundary [Bird, 2

003].

Tectonic Summary Occurred as the result of motion on a northeast striking

reverse fault or thrust fault on the northwestern margin of the Sichuan Basin.

The earthquake's epicenter and focal-mechanism are consistent with it having occurred as the result of movement on the Longmenshan fault or a tectonically related fault.

The earthquake reflects tectonic stresses resulting from the convergence of crustal material slowly moving from the high Tibetan Plateau, to the west, against strong crust underlying the Sichuan Basin and southeastern China.

On a continental scale, the seismicity of central and eastern Asia is a result of northward convergence of the India plate against the Eurasia plate with a velocity of about 50 mm/y. The convergence of the two plates is broadly accommodated by the uplift of the Asian highlands and by the motion of crustal material to the east away from the uplifted Tibetan Plateau.The northwestern margin of the Sichuan Basin has previously experienced destructive earthquakes. The magnitude 7.5 earthquake of August 25, 1933, killed more than 9,300 people.

Dr. Harley Benz, Scientist-in-Charge at the USGS National Earthquake Information Center