文章摘要

文章信息/Info

Title:: Research on the Recent Deformation and Earthquake Risk Assessment in the Tianshan Region

Author(s):: ZHU Shuang; SHI Shuangshuang; (The First Crust Monitoring and Application Center,China Earthquake Administration,Tianjin 300180,China)

Keywords:: Tianshan region; Blocks model; slip rate; baseline; regional strain

摘要:: 利用1999—2018年天山地震带GPS连续站及流动站观测资料,采用线性球面块体模型分别计算了1999—2007期,2009—2013期,2013—2017期的滑动速率,结合天山地震带基线及区域应变结果分析天山地震带近期地壳形变情况,对天山地震带的地震危险性进行评估。结果显示:北天山断裂带西段的挤压滑动速率有微弱的调整,基线结果显示北天山断裂带中西段远场挤压应变加载增强,同时还表现出时空非线性变形过程,需关注其强震危险。南天山断裂带西段的挤压速率处于稳定的高值状态,2013—2017期的挤压速率达到了(-12.5±2.0)mm/a,跨越南天山断裂带西段的基线和应变都是以挤压状态为主,结合地震活动状态的分析,认为该段发生地震的危险性较高。

Abstract:: GPS stations observed from 1999 to 2018 in Tianshan region were collected and analyzed,and the linear sphere block model was used to calculate the slip rates of 1999—2007,2009—2013 and 2013—2017 period.The baseline and regional strain result in recent years in Tianshan region were analyzed,while the recent crustal deformation in Tianshan area was analyzed and earthquake hazard area were evaluated.The results showed that,the compression speed in the western section of the northern Tianshan area has a slight adjustment,while the baseline results showed that there were far field squeezing in west-middle section of the north Tianshan area,but also showed the spatial-tempral nonlinear deformation,it needs to be intentioned.Compression rates in western section of the south Tianshan are in a stable high state,with the value of 2013—2017 period up to-12.5 mm /a.The baselines and strains of the western section of south Tianshan were mainly compressive,combined with the analysis of the seismic activity,it indicates that there was a high risk in the western section of the south Tianshan.