Structural Heterogeneity Controlled Rupture Process of the 2021 Mw 7.1 Fukushima, Japan, Earthquake Revealed by Joint Inversion of Seismic and Geodetic Data

Tan，Yuyang1; Gu，Ning2; Xing，Huilin1,3; Zhang，Yong4; Jin，Zongwei1; Hua，Sibo4; Wang，Jianchao1; Qin，Mutian1; Pang，Shuo1; Li，Sanzhong1,3

2024-03-01

10.1785/0220230259

Seismological Research Letters   影响因子和分区

0895-0695

1938-2057

We determined the rupture model of the 2021 M 7.1 Fukushima earthquake near northeastern Japan in this study and adopted this model to investigate the cause of this earthquake and its aftershocks. The rupture model was obtained through joint inversion of teleseismic, strong-motion and geodetic data. It is shown that the slips were predominantly distributed on the southwest side of the earthquake epicenter, indicating a unilateral rupture event. We observed that the seismic moment was released in three time periods, producing four slip patches on the fault plane. Through comparison, we demonstrated that our joint inversion model was more reliable in describing the rupture process of the Fukushima earthquake than the automatic inversion models determined using only strong-motion data. By jointly analyzing the slip distribution and seismic velocity structure, we found a good correlation between the slip patches and V= V anomalies, suggesting that structural heterogeneities along the fault zone played a critical role in controlling the rupture process of the Fukushima earthquake. In addition, most aftershocks were located in the region characterized by small slips and high V= V, and we demonstrated that they were caused by stress changes due to the presence of fluids and the rupture of the mainshock.

SCI ; EI

英语

其他

GEOSCIENCES

2-s2.0-85186143953

Scopus

1.Frontiers Science Center for Deep Ocean Multispheres and Earth System,Key Lab of Submarine Geosciences and Prospecting Techniques MOE,College of Marine Geosciences,Ocean University of China,Qingdao,China
2.Department of Earth and Space Sciences,Southern University of Science and Technology,Shenzhen,China
3.Laoshan Laboratory,Qingdao,China
4.School of Earth and Space Sciences,Peking University,Beijing,China

Tan，Yuyang,Gu，Ning,Xing，Huilin,et al. Structural Heterogeneity Controlled Rupture Process of the 2021 Mw 7.1 Fukushima, Japan, Earthquake Revealed by Joint Inversion of Seismic and Geodetic Data[J]. Seismological Research Letters,2024,95(2 A):742-757.

Tan，Yuyang.,Gu，Ning.,Xing，Huilin.,Zhang，Yong.,Jin，Zongwei.,...&Li，Sanzhong.(2024).Structural Heterogeneity Controlled Rupture Process of the 2021 Mw 7.1 Fukushima, Japan, Earthquake Revealed by Joint Inversion of Seismic and Geodetic Data.Seismological Research Letters,95(2 A),742-757.

Tan，Yuyang,et al."Structural Heterogeneity Controlled Rupture Process of the 2021 Mw 7.1 Fukushima, Japan, Earthquake Revealed by Joint Inversion of Seismic and Geodetic Data".Seismological Research Letters 95.2 A(2024):742-757.