Ring of Fire subduction of the Pacific Plate and the Philippine Sea Plate. As many as 1,500 earthquakes are recorded yearly, and magnitudes of 4 to 6 are not uncommon. Minor tremors occur almost daily in one part of the country or another, causing some slight shaking of buildings. Major earthquakes occur infrequently; the most famous in the 20th century were: the Great Kantō earthquake of 1923, in which 130,000 people died; and the Great Hanshin earthquake of 17 January 1995, in which 6,434 people died. On March 11, 2011 a magnitude 9.0 earthquake hit Japan, the country's biggest ever and the fifth
2011 Tōhoku earthquake and tsunami when the first earthquake occurred and sustained major damage related to the earthquake and subsequent tsunami. Rolling blackouts of approximately three hours were experienced throughout April and May while TEPCO scrambled to find a temporary power solution. The blackouts affected Tokyo, Kanagawa, Eastern Shizuoka, Yamanashi, Chiba, Ibaraki, Saitama, Tochigi, and Gunma prefectures. Voluntary reduced electricity use by consumers in the Kanto area helped reduce the predicted frequency and duration of the blackouts. By 21 March 2011, the number of households in the north without electricity fell to 242,927. Tōhoku Electric Power was not able to provide the Kanto region with