5:15 PM - 7:15 PM
[SGD03-P05] Simlutaneous estimation of tensile and shear slip components by MCMKF-NIF and application to GNSS data related to seismic swarms in the Noto Peninsula
Keywords:GNSS, seismic swarms
It may be a key to investigate the space-time evolustion of seismic swarm activity and associated crustal deformation. According to Nishimura et al. (2023), a seismic swarm have been observed in Noto Peninsula since December 2020, and transient deformation also have been observed by GNSS networks.
In the JpGU 2024, we computed space-time evolution of tensile and shear slip independently using GNSS data from 2020 to 2023 with MCMKF-NIF. We used shear slip model and opening model for computing, and then the result showed that only one component could not fit to data well. The result of tensile was better than that of shear slip model. This result is consistent with the result of Nishimura et al. (2023), which showed that the crustal deformation during seismic swarms was better estimated by combining the opening and reverse shear slip.
Therefore, it is necessary to estimate the tensile and slip simultaneously. In this study, we modified the existing MCMKF-NIF to be able to estimate the two source components simultaneously. First, numerical experiments were conducted using synthetic data to confirm the accuracy of the MCMKF-NIF. Then we investigate its dependence on the spatial distribution of observation points, and the resolution of tensile and slip were confirmed. After that, we estimated the space-time evolution of tensile and fault slip using observation data in the Noto Peninsula, and discuss the relationship between seismic swarms and crustal deformation from the obtained results.
The SoftBank's GNSS observation data used in this study was provided by SoftBank Corp. and ALES Corp. through the framework of the "Consortium to utilize the SoftBank original reference sites for Earth and Space Science"
In the JpGU 2024, we computed space-time evolution of tensile and shear slip independently using GNSS data from 2020 to 2023 with MCMKF-NIF. We used shear slip model and opening model for computing, and then the result showed that only one component could not fit to data well. The result of tensile was better than that of shear slip model. This result is consistent with the result of Nishimura et al. (2023), which showed that the crustal deformation during seismic swarms was better estimated by combining the opening and reverse shear slip.
Therefore, it is necessary to estimate the tensile and slip simultaneously. In this study, we modified the existing MCMKF-NIF to be able to estimate the two source components simultaneously. First, numerical experiments were conducted using synthetic data to confirm the accuracy of the MCMKF-NIF. Then we investigate its dependence on the spatial distribution of observation points, and the resolution of tensile and slip were confirmed. After that, we estimated the space-time evolution of tensile and fault slip using observation data in the Noto Peninsula, and discuss the relationship between seismic swarms and crustal deformation from the obtained results.
The SoftBank's GNSS observation data used in this study was provided by SoftBank Corp. and ALES Corp. through the framework of the "Consortium to utilize the SoftBank original reference sites for Earth and Space Science"