Yuyang Tan, Ning Gu, Huilin Xing, Yong Zhang, Zongwei Jin, Sibo Hua, Jianchao Wang, Mutian Qin, Shuo Pang, Sanzhong Li
{"title":"基于地震和大地测量数据联合反演的2021 Mw 7.1级日本福岛地震结构非均质性控制破裂过程","authors":"Yuyang Tan, Ning Gu, Huilin Xing, Yong Zhang, Zongwei Jin, Sibo Hua, Jianchao Wang, Mutian Qin, Shuo Pang, Sanzhong Li","doi":"10.1785/0220230259","DOIUrl":null,"url":null,"abstract":"Abstract We determined the rupture model of the 2021 Mw 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 VP/VS 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 VP/VS, and we demonstrated that they were caused by stress changes due to the presence of fluids and the rupture of the mainshock.","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":" 2","pages":"0"},"PeriodicalIF":2.6000,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Structural Heterogeneity Controlled Rupture Process of the 2021 Mw 7.1 Fukushima, Japan, Earthquake Revealed by Joint Inversion of Seismic and Geodetic Data\",\"authors\":\"Yuyang Tan, Ning Gu, Huilin Xing, Yong Zhang, Zongwei Jin, Sibo Hua, Jianchao Wang, Mutian Qin, Shuo Pang, Sanzhong Li\",\"doi\":\"10.1785/0220230259\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Abstract We determined the rupture model of the 2021 Mw 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 VP/VS 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 VP/VS, and we demonstrated that they were caused by stress changes due to the presence of fluids and the rupture of the mainshock.\",\"PeriodicalId\":21687,\"journal\":{\"name\":\"Seismological Research Letters\",\"volume\":\" 2\",\"pages\":\"0\"},\"PeriodicalIF\":2.6000,\"publicationDate\":\"2023-11-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Seismological Research Letters\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1785/0220230259\",\"RegionNum\":3,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"GEOCHEMISTRY & GEOPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Seismological Research Letters","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1785/0220230259","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}
Structural Heterogeneity Controlled Rupture Process of the 2021 Mw 7.1 Fukushima, Japan, Earthquake Revealed by Joint Inversion of Seismic and Geodetic Data
Abstract We determined the rupture model of the 2021 Mw 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 VP/VS 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 VP/VS, and we demonstrated that they were caused by stress changes due to the presence of fluids and the rupture of the mainshock.