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At 9:41:58 a.m. on March 25, 2007, the , a magnitude 6.9 earthquake, struck the Hokuriku region of Japan, near the Noto Peninsula. The earthquake shook the city of Wajima, the city of Nanao, and the town of Anamizu with a seismic intensity of 6+ on Japan's ''shindo'' scale.〔http://www.seisvol.kishou.go.jp/cgi-tmp/shindo_db/27680.html〕 One death, in the city of Wajima, and at least 356 injuries have been reported.〔 == Geology == This earthquake was the result of oblique-slip faulting.〔http://www.gsi.go.jp/WNEW/PRESS-RELEASE/2007-0325.html〕 According to the Geospatial Information Authority of Japan, the fault was 21 km long, 14 km wide and shifted 1.4 m.〔 By using sound waves, the National Institute of Advanced Industrial Science and Technology also found a fault 18~ km long that is supposed to have caused this earthquake.〔 This earthquake was an intraplate earthquake that occurred within the Eurasia Plate, near the boundary with the North American Plate. Noto Peninsula itself was created by pressure pushing up sediment from the south-east, and many folds and reverse faults are in the area. Some strike-slip faults are also found in the area. A 6.6 Mj earthquake also struck Ishikawa Prefecture on February 7, 1993. Since the 1990s, the number of earthquakes with a magnitude of 6.0~ Mj are increasing. Some seismologists say that the seismic activity in West Japan is at its peak, and many earthquakes will occur, like the Great Hanshin earthquake. This earthquake is sometimes considered as one of those earthquakes. Like the 2005 Fukuoka earthquake, it was announced that it "occurred in a area where seismic activity was relatively quiet", but earthquakes are possible anywhere in Japan and its surrounding areas. Also this earthquake's fault was out in sea, so it was not simulated in the seismic danger maps, since most of the faults simulated are inland faults. Some seismologists are trying to simulate these kind of earthquakes as well as inland earthquakes. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「2007 Noto earthquake」の詳細全文を読む スポンサード リンク
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