Development of an estimation technique on propagation velocity with short-time mearurement for mobile observation

Research Project

Project/Area Number	15K06643
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Earth system and resources engineering
Research Institution	Center for Environmental Science in Saitama
Principal Investigator	Shiraishi Hidetaka 埼玉県環境科学国際センター, 研究推進室, 研究推進室長 (60415396)
Research Collaborator	ASANUMA Hiroshi HACHINOHE Shoichi ISHIYAMA Takashi HAMAMOTO Hideki
Project Period (FY)	2015-04-01 – 2019-03-31
Project Status	Completed (Fiscal Year 2018)
Budget Amount *help	¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000) Fiscal Year 2017: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000) Fiscal Year 2016: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000) Fiscal Year 2015: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Keywords	地球計測 / 地震波干渉法 / 複素コヒーレンス関数 / 微動探査
Outline of Final Research Achievements	In this research, we have examined to simplify the exploration techniques which estimate the underground structures with measuring the propagation velocities (group velocities, phase velocities) of waves (seismic waves, tremors) between two stations. These exploration techniques are mainly used in the field of earthquake disaster prevention or resource explorations. As a result, we have found the feasibility of a simple estimation technique that can capture changes in the propagation velocity between stations deployed along straight line, though it could not reach the implementation of the propagation velocity measurement with short-time observation at only two stations. This exploration technique requires the conventional technique (for example, direct estimation method) complementary to estimate parameters of wave sources, however if it can be put to practical use, it is considered that local structural changes can be easily detected.
Academic Significance and Societal Importance of the Research Achievements	本研究は、地震被害の予測等に必要な地下構造の推定技術に関するものであり、現行技術における観測点配置や計測時間長に係る課題の緩和・解消を図るために行ったものである。その結果、本研究で導いた推定技術と従来法を相補的に活用することで、新たな調査方法を実現できる可能性を見いだした。この方法を実用化することで、直線を主体とする簡便な観測点配置と短時間の計測で局所的な構造変化を容易に検出できる可能性があるため、地震被害予測等に必要な地下構造情報の収集に役立つものと考えられる。