地质力学学报2017，Vol.23Issue(4)：507-514,8.
2017年四川九寨沟Ms7.0地震InSAR同震形变场及发震构造探讨
INSAR CO-SEISMIC DEFORMATION OF 2017 M s 7. 0 JIUZHAIGOU EARTHQUAKE AND DISCUSSIONS ON SEISMOGENIC TECTONICS
摘要
Abstract
An Ms7. 0 earthquake occurred in Jiuzhaigou county on Aug. 8, 2017. Tectonic location is the NE part of Bayan-Har block, with epicenter in the earthquake-free zone surrounded by Minjiang fault, Tazang fault, Huya fault as well as Xueshanliangzi fault, and where is of free earthquake zone. Which is the seismogenic fault? How to define the relationship between this earthquake and the neighbor faults? Does it have the causal association with huge earthquakes in recent years? The answers to those questions are of great significance to understand the current tectonic activity pattern, predict seismic development trend and deploy earthquake geological disaster prevention and control. Using two periods of Sentinel-1 SAR data to carry out InSAR survey, co-seismic deformation ( -13~28 cm) and movement direction within 2000 km2 in meizoseismal area were measured, showing passive singe wall strike-slip and thrust ground deformation. Based on analysis of focal mechanism solution, fault distribution, tectonic background and recent seismic migration, conclusions are made as follows. The seismogenic structure is the end structure of an arc rotation system in northeastern boundary of Bayan-Har block, and the seismogenic fault is the southern branch of Tazang fault, with the trend to connect with Huya fault, therefore, the section between them should be paid more attention to in the future. There are certain spatio-temporal genetic relation between Jiuzhaigou earthquake and Wenchuan earthquake:in condition of ruptures existed in north and south boundary of Bayan-Har block, the 2008 Wenchuan earthquake induced new rupture in east edge to accelerate block eastward extrusion, and 2013 Ludian earthquake released tectonic stress in southern section, further exacerbating stress concentration in northeastern angle, which led to the 2017 Jiuzhaigou earthquake.关键词
九寨沟地震/干涉雷达/巴颜喀拉地块/塔藏断裂Key words
Jiuzhaigou earthquake/InSAR/Bayan-Har block/Tazang fault分类
天文与地球科学引用本文复制引用
姚鑫,周振凯,李凌婧,刘星洪,姚佳明..2017年四川九寨沟Ms7.0地震InSAR同震形变场及发震构造探讨[J].地质力学学报,2017,23(4):507-514,8.基金项目
国家自然科学基金项目 (41672359) （41672359）
中国地质调查局工作项目 (DD20179282, DD20160272) （DD20179282, DD20160272）
中央级公益性科研院所基本科研业务费项目 (DZLXJK201611) （DZLXJK201611）
