CT理论与应用研究2025，Vol.34Issue(2)：163-174,12.DOI:10.15953/j.ctta.2024.257
郯庐断裂中南段地壳速度结构与地震活动性研究
Crustal Velocity Structure of the Middle-Southern Segment of the Tanlu Fault Zone(China)and its Correlation with the Seismic Activity in the Region
摘要
Abstract
The Tanlu fault zone is the largest and most active Quaternary fault in eastern China.An M8.5 earthquake occurred in 1668 in Tancheng City located on the southern segment of the Tanlu fault.In this study,we analyzed the crustal velocity structure of the Tanlu fault zone and assessed its relationship with the regional seismic activity,using a large dataset of the arrival times of the primary(P)and secondary(S)waves recorded at 121 permanent seismic stations in and around the middle-southern segments of the Tanlu fault;in total,we used the data of 8528 local earthquakes.We developed three-dimensional(3D)images of the P-wave(VP)and S-wave(VS)velocities and the VP/VS ratio,using the TOMOG3D(a seismic tomography method).The tomography results revealed the following features:(1)a significant velocity segmentation feature exists in the middle-southern segments of the Tanlu fault zone;this feature can be divided into Section A(located in the north of Tancheng),Section B(extending from Tancheng to Mingguang),and Section C(extending from Mingguang to Wuxue).(2)Large earthquakes are mainly distributed at the junction of the high-and low-velocity anomalies.(3)A strong correlation was noted between the velocity structure and seismic activity,especially in Suqian(where a clear low-velocity anomaly that corresponded to a seismic gap was observed).Our study provides new insights into the crustal heterogeneity and seismic activity in the middle-southern segments of the Tanlu fault zone.关键词
地震层析成像/郯庐断裂带中南段/地壳速度结构/地震活动性Key words
seismic tomography/middle-southern segments of the Tanlu fault zone/crustal velocity structure/seismic activity分类
天文与地球科学引用本文复制引用
夏心茹,江国明,赵大鹏..郯庐断裂中南段地壳速度结构与地震活动性研究[J].CT理论与应用研究,2025,34(2):163-174,12.基金项目
深地国家科技重大专项(郯-庐断裂带大震孕育成灾规律研究(2024ZD1000405)). （郯-庐断裂带大震孕育成灾规律研究(2024ZD1000405）
