Hypocenter distribution of the main- and aftershocks of the 2005 Off Miyagi Prefecture earthquake located by ocean bottom seismographic data

Autor: Toshihiko Kanazawa, Kimihiro Mochizuki, Masayuki Tanaka, Asako Kuwano, Masao Abe, Tomoaki Yamada, Yojiro Yamamoto, Gou Fujie, Yoshiyuki Kaneda, Shuichi Kodaira, Kazuo Nakahigashi, Masanao Shinohara, Ryota Hino, Eiichiro Araki, Gen Aoki, Kouetsu Minato, Minoru Nishino, Nariaki Okawara
Rok vydání: 2006
Předmět:
Zdroj: Earth, Planets and Space. 58:1543-1548
ISSN: 1880-5981
DOI: 10.1186/bf03352658
Popis: The preliminary hypocenter distribution of the 2005 Off Miyagi Prefecture earthquake and its aftershocks is estimated using data from five ocean bottom and six onshore seismic stations located around the rupture area of the earthquake. The epicenter of the mainshock is relocated at 38.17°N, 142.18°E, and the focal depth is estimated to be 37.5 km. The aftershocks surrounding the mainshock hypocenter form several clusters that are concentrated along a distinct landward dipping plane corresponding to the plate boundary imaged by the previous seismic experiment. The strike and dip angles of the plane agree well with those of the focal mechanism solution of the mainshock. The size of the plane is about 20×25 km2 in the strike and dip directions, which is similar to that of the large coseismic slip area. The up-dip end of the planar distribution of the aftershocks corresponds to the bending point of the subducting oceanic plate, suggesting that the geometry of the plate boundary affects the spatial extent of the asperity of the 2005 earthquake
Databáze: OpenAIRE