基于InSAR形变数据分析台湾纵谷断层南段现今运动特征

摘要/Abstract

摘要： 本文利用2007—2010年花东纵谷南段区域的InSAR形变数据作为约束, 采用分段断层模型和层状介质模型, 反演中国台湾东部纵谷断层南段滑动速率空间分布, 并据此分析断层运动特征。研究结果表明, 纵谷断层南段整体以逆冲运动为主, 兼具左旋走滑运动。纵谷断层南段的滑动速率具有空间非均匀性, 在空间上可以细分为深浅两个极值区, 浅部(0~15 km)最大滑动速率为10 cm/a, 位于深度2.5 km左右; 深部(15~30 km)最大滑动速率为21 cm/a, 位于深度25 km左右。反演结果与用重复地震估算的深部滑动速率基本吻合。

关键词: InSAR形变, 断层运动, 反演, 台湾纵谷断层

Abstract: Based on segmented fault model and layered model, this paper use constraints from synthetic aperture radar interferometry (InSAR) deformation observations between 2007 and 2010, to invert spatial distribution of slip rate in the southern Longitudinal Valley Fault in eastern Taiwan, China, and then analyze the characteristics of fault movement. The results show that, the southern Longitudinal Valley fault movement is dominanted by thrust with less left-lateral component. The slip rate of the southern Longitudinal Valley Fault has a non-uniform spatial distribution, and it can be divided into two extremes, the maximum slip rate in the shallow part (0~15 km) is about 10 cm/a, located at the depth of about 2.5 km; and the maximum slip rate in the deep part (15~30 km) is about 21 cm/a, located at the depth of about 25 km. The inversion results are consistent with the deep slip rate estimated by repeating earthquake.

Key words: InSAR deformation, Fault movement, Inversion, The Longitudinal Valley fault

中图分类号:

P315.7

李海艳, 邵志刚, 马宏生, 王芃, 戴宗辉. 基于InSAR形变数据分析台湾纵谷断层南段现今运动特征[J]. 地震, 2016, 36(3): 25-33.

LI Hai-Yan, SHAO Zhi-Gang, MA Hong-Sheng, WANG Peng, DAI Zong-Hui. Current Movement Characteristics of the Southern Longitudinal Valley Fault Basedon InSAR Deformation Data[J]. EARTHQUAKE, 2016, 36(3): 25-33.

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