Japan Geoscience Union Meeting 2021

Presentation information

[J] Poster

S (Solid Earth Sciences ) » S-GD Geodesy

[S-GD01] Geodesy and Global Geodetic Observing System

Fri. Jun 4, 2021 5:15 PM - 6:30 PM Ch.13

convener:Koji Matsuo(Geospatial Information Authority of Japan), Yusuke Yokota(Institute of Industrial Science, The University of Tokyo), Toshimichi Otsubo(Hitotsubashi University)

5:15 PM - 6:30 PM

[SGD01-P02] Non-linear visco-elastic modeling of post-seismic gravity change

*Changda Yan1, SHINICHI MIYAZAKI1 (1.Graduate School of Science, Kyoto University)

Keywords:Post-seismic, gravity, GRACE

Visco-elastic model plays a pivotal role in helping to explain post-seismic displacement and gravity change. Many modelling methods and programs have been developed based on Maxwell, Burgers and several other linear visco-elastic mechanisms. However, the present linear visco-elastic model fails to cover the entire picture of post-seismic displacement and gravity change. Especially when it comes to the time period 1~2 years immediately after an earthquake. Therefore, we attempt to expand the now linear model into non-linear to improve our understanding of the post-seismic process.



Our method of realizing non-linear gravity change model is based on the theory of spectral finite element method . We combined it with the non-linear visco-elastic model to form our new method. Improvement of program performance is also made after combining the two theory. A new program based on FORTRAN is created independently to demonstrate our method.



Here, we present some examples of model simulated post-seismic gravity change based on the non-linear method. GRACE satellite gravity observation data is used to compare with the simulated gravity change. Our novel non-linear gravity change model could serve as an alternative for the interpretation of observed satellite gravity change and ground displacement after the occurrence of an earthquake.