青藏高原西部及邻区构造应力场反演和断层滑动趋势分析  

Inversion of Tectonic Stress Field and Fault Slip Tendency Analysis in Western Tibetan Plateau and Adjacent Areas

作　　者：杨颖[1] 解朝娣[1] 徐彦[1] 相传芳 刘本玉[1] YANG Ying;XIE Zhaodi;XU Yan;XIANG Chuanfang;LIU Benyu(School of Earth Sciences,Yunnan Universiy,South-Dongwaihuan Road,Kunming 650091,China;Yudong Earthquake Monitoring Station,Zhaotong Earthquake and Disaster Mitigation Bureau,19 Fengyuan Road,Zhaotong 657000,China)

机构地区：[1]云南大学地球科学学院,昆明市650091 [2]昭通市防震减灾局渔洞地震监测站,云南省昭通市657000

出　　处：《大地测量与地球动力学》2022年第7期694-699,共6页Journal of Geodesy and Geodynamics

基　　金：国家自然科学基金(41964001);地震动力学国家重点实验室开放基金(LED2019B04)。

摘　　要：基于Global CMT提供的1976-01-01~2015-12-31期间1255个M;≥3.5地震的震源机制解,利用FMSI方法对青藏高原西部及邻区(新疆西部地区)应力场进行反演,得到区域应力场特征,并分析西昆仑断裂带及阿尔金断裂带的断层滑动趋势。结果表明,青藏高原西部及邻区的最大主压应力轴σ;整体呈NNE-SSW向,自西向东顺时针旋转;最小主压应力轴σ;整体呈NWW-SEE向。最大主压应力轴σ;倾角大小约为5°~9°,说明该地区的构造应力场以水平运动为主。西昆仑断裂带及阿尔金断裂带具有较强的滑动趋势(T_(s)≥0.5),说明西昆仑断裂带及阿尔金断裂带未来失稳滑动的可能性较大。Based on 1 255 seismic source mechanism solutions of M;≥3.5 during 1976-01-01~2015-12-31 provided by Global CMT, we use the FMSI method to invert the stress field in the western Qinghai-Tibet plateau and its adjacent areas(western Xinjiang). We analyze the trend of fault sliding in the west Kunlun fault zone and Altyn Tagh fault zone. The results show that the maximum principal compressive stress axis σ;in the western Tibetan plateau and neighboring areas is in the NNE-SSW direction and rotates clockwise from west to east;the minimum principal compressive stress axis σ;is in the NWW-SEE direction. The dip of the maximum principal compressive stress axis σ;is about 5°~9°, indicating that the tectonic stress field in this area is dominated by horizontal motion. The west Kunlun fault zone and Altyn Tagh fault zone have a strong sliding trend(T_(s)≥0.5), indicating that the possibility of future destabilization and sliding of the west Kunlun fault zone and Altyn Tagh fault zone is larger.

关 键 词：青藏高原西部及邻区 震源机制解 FMSI方法 应力场反演 断层滑动趋势分析 

分 类 号：P315[天文地球—地震学]