摘要
本文首先利用加卸载响应比孕震积分,对2001年以来新疆境内南天山西段和喀什—乌恰交汇区发生的4次MS≥6.0地震,进行了震例检验。结果显示,孕震初期孕震积分在背景值附近波动,变化平缓。随着孕震程度的加剧,孕震积分不断增加至峰值点,快速回落过程中或恢复后发震。我们还将加卸载响应比孕震积分初步应用到南天山西段的部分定点形变资料中,对比分析了哈拉峻台、乌恰台钻孔倾斜以及乌什水管仪、伸缩仪和体应变趋势日均值与以台站为中心,250km为半径的加卸载响应比孕震积分时序图。结果表明,①哈拉峻台和乌恰台区域内构造应力场应力处于不断加载的过程,引起了定点形变资料速率的大幅度、不稳定变化;②当构造应力场上的应力处于缓慢不断加载的过程时,会引起定点形变测项速率方向发生改变,表现形式为趋势异常;③目前,南天山西段构造应力场应力水平处于不断加载的过程。
Firstly, testing on the four earthquake cases （Ms≥6.0） from 2001 to 2012 oc- curred successively in the western part of southern Tianshan mountain and Kashi-Wuqia area of Xinjiang for using the Load/Unload Response Ratio Seismogenic Integral. The re- sults showed that the seismogenic integral fluctuated around the background change smoothlyin early seismogenic stage. With the intensification of stress and seismogenic in- tegral increasing to the peak point, earthquakes occured during the rapid decline or after the resumption. Then, weapply the Load/Unload Response Ratio Seismogenic Integralto the fixed site deformation data. Contrasting and analyzing the Load/Unload Response Ra- tio Seismogenic Integral with 250 km radius surrounding Machang, Halajun, Wuqia and Kashi stations in the western part of southern Tianshan mountain, as well as the sequence chart of Seismogenic Integral on the affiliated stations. The result indicated that （1） the tectonic stress field in Machang, Halajun and Wuqia station region is in a process of con- tinuous load currently, which gives rise to the huge and unsteady change in the datum rate of fixed-point deformation; （2） the measurement rate direction of precursory permanent deformation changes when the stress on tectonic stress field is in constant load slowly, their manifestations are trend anomaly; （3） Currently, the tectonic stress field stress level regions in the western part of the southern Tianshan isthe process of continuous loading.
出处
《地震》
CSCD
北大核心
2014年第2期89-97,共9页
Earthquake
基金
2013年度震情跟踪合同制定向工作任务(2013020107)
新疆地震科学基金(201201)联合资助
关键词
加卸载响应比
孕震积分
构造应力场
定点形变
新疆地区
Load/Unload Response Ratio
Seismogeniclntegral
Tectonic stress field
Stress load
Fixed site deformation
