Extraction of wave propagation characteristics from spatial continuity of seismic and tsunami wavefields

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K04006
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17040:Solid earth sciences-related
• Research Institution: Hirosaki University
• Principal Investigator: Maeda Takuto 弘前大学, 理工学研究科, 教授 (90435579)
• Co-Investigator(Kenkyū-buntansha): 小菅 正裕 弘前大学, 理工学研究科, 客員研究員 (90142835)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 地震波 / 津波 / 数値シミュレーション / データ同化

Outline of Final Research Achievements

This research aims to extract information based on the spatial continuity of wavefield from dense seismic and tsunami observation network data. It involves the development of an information extraction method using seismic wave potential decomposition and a data assimilation method common to both earthquakes and tsunamis. For the former, a method for separating P-SV/SH components in heterogeneous media was examined through numerical simulations, demonstrating its effectiveness. For the latter, a new method for highly-accurate estimation of the wavefield based on adjoint equations was developed, and its applicability to real-time forecasting problems was demonstrated through numerical experiments.

Free Research Field

地震学

Academic Significance and Societal Importance of the Research Achievements

稠密な地震および津波記録からの情報抽出方法の高度化を通じて，地震波解析においてはより高精度な地球内部構造や震源推定への応用が，そして津波記録解析においてはより正確な即時予測への応用がそれぞれ今後の発展として期待される．さらに，アジョイント法に基づくデータ同化は地震学における多くの逆問題や時間反転イメージングとも密接に関連するものであり，今後のさらなる研究開発に資すると期待される．