[S-GD02] Crustal Deformation

[SGD02-P07] Joint analysis of GNSS, tilt, and strain data for spatio-temporal slip distributions of short-term SSEs – Synthetic Test –

*Suguru Yabe¹, Tadafumi Ochi¹, Norio Matsumoto¹, Takanori Matsuzawa² (1.National Institute of Advanced Industrial Science and Technology, 2.National Research Institute for Earth Science and Disaster Resilience)

Keywords:Strain, Tilt, GNSS, SSE

Short-term Slow slip events (SSEs) are one of the important aseismic phenomena in subduction zones to understand strain accumulation on the plate interface. In southwest Japan, sizes of short-term SSEs are usually less than Mw ~6.2, which is difficult to monitor detailed slip patterns using only GNSS data. Instead, tilt and strain data are used for this purpose. Tilt data are maintained by the National Institute of Earth Science and Disaster Resilience (NIED), whereas strain data are maintained by Japan Meteorological Agency (JMA) in the Tokai region and by Geological Survey of Japan (GSJ) in southwest Japan. Monitoring of short-term SSEs have been conducted by some researchers and institutions. However, detailed spatio-temporal slip distributions of short-term SSEs have not been addressed. In this study, we developed a joint inversion method for spatio-temporal slip distributions of short-term SSEs. We jointly use GNSS, tilt, and strain data in the following manner. GNSS data is used to constrain only spatial distributions of slip, whereas tilt and strain data are used to constrain both spatial and temporal evolution of the slip distributions. In this presentation, we will conduct synthetic tests using the developed method and discuss the resolution of inverted results.