[SSS13-P06] Source Process of the 2018 Hokkaido Eastern Iburi Earthquake Inferred from Strong Motion Data and Green's Functions Based on Three-Dimensional Velocity Structure Model
Keywords:the 2018 Hokkaido Eastern Iburi earthquake, strong motion data, source rupture process, three-dimensional velocity structure model
The estimated source model has small slip in the vicinity of the hypocenter, but significant slip is found in the depth range from about 22 km to 32 km. The rupture mainly propagated toward shallow and southwest direction. Considering crustal structure in this region (e.g., Iwasaki et al., 2004; Kita et al., 2012), the large slip area (asperity) is located in the middle-to-lower crust, and its rupture does not reach the upper crust. The depth range of significant slip is consistent with the spatial distribution of early aftershocks. Later aftershocks occurring in shallower depth are thought to occur outside the mainshock's source fault.
Acknowledgements: Strong motion data from K-NET, KiK-net and F-net (NIED) and JMA unified hypocenter catalog were used in this study. This study was supported by the Grant-in-Aid for Special Purposes 18K19952 (PI: Prof. Hiroaki Takahashi at Hokkaido University) from MEXT.