沈み込みプレート境界における断層セグメント間の相互作用

• 有吉 慶介

  東北大学大学院理学研究科地震・噴火予知研究観測センター

• 松澤 暢

  東北大学大学院理学研究科地震・噴火予知研究観測センター

• 矢部 康男

  東北大学大学院理学研究科地震・噴火予知研究観測センター

• 長谷川 昭

  東北大学大学院理学研究科地震・噴火予知研究観測センター

• 加藤 尚之

  東京大学地震研究所

書誌事項

タイトル別名

• Interaction between Fault Segments on a Subducting Plate Interface
• シズミコミ プレート キョウカイ ニ オケル ダンソウ セグメントカン ノ ソウゴ サヨウ

抄録

A two-dimensional (2D) numerical simulation of seismic cycles on the plate boundary in a subduction zone is performed based on a rate- and state-dependent friction law to obtain insight into complicated cycle of interplate earthquakes off Miyagi Prefecture and to investigate possible precursory sliding behavior. Assuming that the complexity of seismic cycle such as the off Miyagi Prefecture Earthquake is mainly due to the heterogeneity of frictional properties, we divide the plate boundary into five segments along dip direction: three frictionally stable segments and two (shallower and deeper) seismogenic segments are placed alternately. From many trial simulation results, we find that the frictional parameters (b-a)and d_c in the deeper seismogenic segment should be smaller than those in the shallower segment in order to generate earthquakes in the deeper segment more frequently than in the shallower segment. The simulation results show that preseismic, coseismic, and postseismic slip in a seismogenic segment tends to become larger when it occurs just after the earthquake in the other seismogenic segment, because the previous earthquake in the other seismogenic segment keeps on forward slip through the intermediate aseismic segment. We also find that the stress rate in the down-dip direction in the vicinity of the lower edge of the deeper seismogenic segment is compressional for the period of about one year prior to the occurrence of the earthquake in the segment while it is tensional prior to the event in the shallower segment. This result suggests that seismic activity change in a slab can be a clue to the intermediate-term prediction of large interplate earthquakes.

収録刊行物

• 地震　第２輯

  地震　第２輯 59 (4), 309-324, 2007

  公益社団法人 日本地震学会

キーワード

• Numerical simulation
• Constitutive friction law
• Seismic cycle
• Preseismic slip
• Seismicity change

詳細情報

• CRID: 1390282679279734400
• NII論文ID: 10020152337
• NII書誌ID: AN00305741
• DOI: 10.4294/zisin.59.309
• ISSN: 18839029
• ISSN: 2186599X
• ISSN: 00371114
• NDL書誌ID: 8870116
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I8870116
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• 抄録ライセンスフラグ: 使用不可