Estimation of the spatio-temporal structure of strain-field associated with slow slip events using GPS and strainmeter networks

Research Project

Project/Area Number	23540503
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Solid earth and planetary physics
Research Institution	National Institute of Advanced Industrial Science and Technology
Principal Investigator	OHTANI Ryu 独立行政法人産業技術総合研究所, 地質情報研究部門, 主任研究員 (50356648)
Co-Investigator(Kenkyū-buntansha)	NAWA Kazunari 国立研究開発法人産業技術総合研究所, 地質調査総合センター地質情報研究部門, 研究グループ長 (20262082)
Project Period (FY)	2011-04-28 – 2015-03-31
Project Status	Completed (Fiscal Year 2014)
Budget Amount *help	¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000) Fiscal Year 2013: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2012: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000) Fiscal Year 2011: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
Keywords	ゆっくり地震 / GPS連続観測網 / 歪計 / ウェーブレット変換 / 地殻変動 / GNSS連続観測網 / 地殻歪場
Outline of Final Research Achievements	Comparison of strain variations measured by borehole strainmeters with GPS-derived strain is carried out to investigate the characteristics of the long-term measurement of strainmeters over the time scale of several weeks. The result shows that there are seasonal variations both in strainmeter and GPS where the amplitudes are consistent each other at some stations, but they are not always in phase and many other stations do not show good agreement between GPS and strainmeter. Strain-field variations during and inter slow slip events are also investigated at Sakishima archipelago using wavelet analysis to reveal the spatio-temporal structure of slow slip events' process.