10:00 AM - 10:15 AM
[SSS10-05] Post-seismic deformation of 2016 Kumamoto Earthquake by continuous GNSS network
Keywords:Continuous GNSS observation, post-seismic deformation
Bernese GNSS Software Ver. 5.2 is used for GNSS data analysis of our newly sites together with GEONET and JMA GNSS sites for volcanoes in Kyushu for the period from April 15 to December 31, 2016. We used CODE precise ephemerides and CODE Earth rotation parameters. The coordinates of the GNSS sites are estimated respect to ITRF2008.
Large post-seismic deformation in horizontal component was observed at CGNSS sites near Hinagu and Futagawa fault zone. However, there is almost no observation in vertical component. Largest post-seismic deformation of 11cm from April to December, 2016 is observed in NS-component at MIFN, which is located east side of Hinagu fault zone. It seems that post-seismic deformation does not come to stop.
After slip model is assumed for initial post-seismic deformation from April to July, 2016. We assumed two faults, one is located in Futagawa fault zone and the other is Hinagu fault zone. Fault parameters of length, width, strike, dip, amount of slip, position are estimated by simulated annealing method. Top and bottom of fault plane are 0.1 to 40 km in Hinagu fault and 0.8 to 32 km in Futagawa fault. Two fault planes extended to mantle. It suggests that there are several phenomena in initial post-seismic deformation, effect of viscoelastic etc.