Zheng Ao, Yu Xiangwei, Bai Chengyuan, Xu Wenbin, Qian Jiaqi, Zhang Wenbo, Chen Xiaofei
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China.
School of Resources and Geosciences, China University of Mining and Technology, Xuzhou, China.
Sci Rep. 2024 Dec 28;14(1):31496. doi: 10.1038/s41598-024-82971-x.
The 2024 Hualien M 7.4 earthquake struck the Longitudinal Valley, which accommodates the partial collision between the Eurasian and Philippine Sea plates. As the most significant event in Taiwan since the 1999 Chi-Chi M 7.6 earthquake, it presents a distinct opportunity for investigating the current rupture behavior related to the northern Longitudinal Valley. The spatiotemporal rupture process of the Hualien earthquake is reconstructed through the analysis of geodetic and seismic observations. We demonstrate that the Hualien earthquake occurs on a blind listric fault, manifesting as a unilateral rupture primarily extending toward the NNE. The slip distribution exhibits a compact pattern dominated by the thrust faulting. As indicated by the increased Coulomb failure stress, the 2022 Chihshang M 6.5 and M 6.9 earthquakes cause a triggering effect on the Hualien earthquake. The Hualien earthquake also promotes the occurrence of a seismic swarm at the southernmost tip of its rupture area.
2024年花莲7.4级地震发生在纵谷地区，该地区是欧亚板块与菲律宾海板块部分碰撞的区域。作为自1999年集集7.6级地震以来台湾发生的最重大事件，它为研究与纵谷北部相关的当前破裂行为提供了独特的机会。通过对大地测量和地震观测的分析，重建了花莲地震的时空破裂过程。我们证明，花莲地震发生在一条隐伏的铲形断层上，表现为主要向北北东方向延伸的单侧破裂。滑动分布呈现出以逆冲断层为主的紧凑模式。库仑破裂应力增加表明，2022年池上6.5级和6.9级地震对花莲地震产生了触发作用。花莲地震还促使其破裂区域最南端发生了地震群活动。
