1945年三河地震（<I>M</I> ＝6.8）に伴う地殻変動と震源断層モデルの再検討

• 高野 和友

  国土地理院測地部

• 木股 文昭

  名古屋大学大学院環境学研究科地震火山・防災研究センター

書誌事項

タイトル別名

• Re-examination of Ground Deformation and Fault Models of the 1945 Mikawa Earthquake (<I>M</I> =6.8)

抄録

This study reexamines the ground deformation and fault slip model of the 1945 Mikawa earthquake (M =6.8), central Japan. We reevaluate two geodetic data sets from the years 1886/1887 and 1955/56 that were obtained from the Geographical Survey Institute; these data sets consist of displacements calculated from the net adjustment of triangulation surveys carried out before and after the Mikawa earthquake. We remove the interseismic deformation and coseismic deformation of the 1944 Tonankai earthquake from the two unique data sets used in our analysis. Maximum coseismic horizontal displacements of over 1.4 m were detected to the west of the Fukozu fault. We estimated the coseismic slip by analyzing our data set. The geometry of the fault planes was adopted from a recent seismicity study and from the surface earthquake fault of this area. The best fit to the data is obtained from two faults along the sections running north and south of the Fukozu and Yokosuka faults. The estimated uniform-slip elastic dislocation model consists of two adjacent planes. The fault also appeared to connect the sections running north and south of the Fukozu and Yokosuka faults. Because it can suitably explain the coseismic deformation due to two earthquake source faults, the earthquake source fault is not admitted under the section for the run. The mechanism is considered to be two reverse faults with right-lateral components. The estimated slips for the two source faults are 2.5 m and 1.4 m, respectively. The pressure axis is directed along NE-SW or E-W. The total seismic moment determined from this model is 1.6 × 10¹⁹ Nm, corresponding to M_w=6.7.

収録刊行物

• 地震　第２輯

  地震　第２輯 62 (2+3), 85-96, 2009

  公益社団法人 日本地震学会

キーワード

• 1945 Mikawa earthquake
• Triangulation
• Net adjustment
• Fault model
• Coseismic deformation

詳細情報

• CRID: 1390001204303386368
• NII論文ID: 130004697465
• DOI: 10.4294/zisin.62.85
• ISSN: 18839029
• ISSN: 2186599X
• ISSN: 00371114
• 本文言語コード: en
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可