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Earth, Planets and Space

, Volume 58, Issue 12, pp 1543–1548 | Cite as

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

  • Ryota Hino
  • Yojiro Yamamoto
  • Asako Kuwano
  • Minoru Nishino
  • Toshihiko Kanazawa
  • Tomoaki Yamada
  • Kazuo Nakahigashi
  • Kimihiro Mochizuki
  • Masanao Shinohara
  • Kouetsu Minato
  • Gen Aoki
  • Nariaki Okawara
  • Masayuki Tanaka
  • Masao Abe
  • Eiichiro Araki
  • Shuichi Kodaira
  • Gou Fujie
  • Yoshiyuki Kaneda
Open Access
Letter

Abstract

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

Key words

Off Miyagi Prefecture earthquake interplate seismicity Ocean bottom seismographs 

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Copyright information

© The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. 2006

Authors and Affiliations

  • Ryota Hino
    • 1
  • Yojiro Yamamoto
    • 1
  • Asako Kuwano
    • 1
  • Minoru Nishino
    • 1
  • Toshihiko Kanazawa
    • 2
  • Tomoaki Yamada
    • 2
  • Kazuo Nakahigashi
    • 2
  • Kimihiro Mochizuki
    • 2
  • Masanao Shinohara
    • 2
  • Kouetsu Minato
    • 3
  • Gen Aoki
    • 3
  • Nariaki Okawara
    • 4
  • Masayuki Tanaka
    • 4
  • Masao Abe
    • 4
  • Eiichiro Araki
    • 5
  • Shuichi Kodaira
    • 5
  • Gou Fujie
    • 5
  • Yoshiyuki Kaneda
    • 5
  1. 1.Graduate School of ScienceTohoku UniversitySendaiJapan
  2. 2.Earthquake Research InstituteThe University of TokyoTokyoJapan
  3. 3.Sendai District Meteorological ObservatoryJapan Meteorological AgencySendaiJapan
  4. 4.Seismological and Volcanological DepartmentJapan Meteorological AgencyTokyoJapan
  5. 5.Japan Agency for Marine-Earth Science and TechnologyYokosukaJapan

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