Statistics of P-wave polarizations and its application to high-sensitivity earthquake detection

2014 Fiscal Year Final Research Report

• Project/Area Number: 25887055
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Solid earth and planetary physics
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: UCHIDE TAKAHIKO 独立行政法人産業技術総合研究所, 活断層・火山研究部門, 研究員 (80713049)
• Project Period (FY): 2013-08-30 – 2015-03-31
• Keywords: 固体地球物理学 / 地震学 / 振動極性 / 時系列解析 / 地震検出

Outline of Final Research Achievements

Statistics of P-wave Polarity: The P-wave polarity azimuths are overall consistent with the back azimuth, but some of them deviates in case of specific back azimuth. This can be explained by horizontal heterogeneity of the seismic velocity structure. We found a problem that rectlinear motions are detected in case with no earthquakes, and solved by using high-angle motions only, since such noises are with low-angle motions.
Development of High-sensitivity Earthquake Detection Method: We applied the polarity analysis to the continuous seismic data recorded in and around the Hida area, Japan. The results from the multiple stations are used for the estimation of epicenter which manifests the existence of earthquakes. We detected 44 % of events included in the JMA hypocenter catalog.

Free Research Field

震源地震学