日本地球惑星科学連合2018年大会

講演情報

[EE] Eveningポスター発表

セッション記号 S (固体地球科学) » S-CG 固体地球科学複合領域・一般

[S-CG53] Science of slow earthquakes: Toward unified understandings of whole earthquake process

2018年5月23日(水) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 7ホール)

コンビーナ:井出 哲(東京大学大学院理学系研究科地球惑星科学専攻)、廣瀬 仁(神戸大学都市安全研究センター)、氏家 恒太郎(筑波大学生命環境系、共同)、波多野 恭弘(東京大学地震研究所)

[SCG53-P26] Fast and slow slip events emerge due to fault geometrical complexity

*Pierre Romanet1Harsha S. Bhat2 (1.Department of Earth and Planetary Science, University of Tokyo、2.Laboratoire de Géologie, École Normale Supérieure)

キーワード:Seismic cycle, Complex fault geometry

Faults are always acting in network, and the geometry of faults themselves is extremely complex at all scale. However so far very few models of the seismic cycle have tried to incorporate the true geometry of faults. This is mainly due to computational reasons that make non-planar geometries out of reach because of computational time. To overcome this issue, we develop a new quasi dynamic model of earthquakes, with rate and state friction law, that is accelerated through the use of Hierarchical matrices. We show, through many examples, that the geometry alone brings a lot of natural complexities that is actually seen in the seismic cycle. It changes the recurrence time of earthquakes making it more chaotic, it enhances slow earthquakes. An other big challenge of seismic cycles models would be to catch scaling laws such as Omori or Gutenberg. We show that interaction of faults may resolve some of these scaling law issues.