新疆天山地区b值时空变化特征  

Temporal and Spatial Variations of b-value in Tianshan,Xinjiang

作　　者：张琳琳[1] 唐兰兰[1] 

机构地区：[1]新疆维吾尔自治区地震局,乌鲁木齐830011

出　　处：《地震》2015年第3期93-101,共9页Earthquake

基　　金：新疆地震科学基金(201404)资助

摘　　要：通过分析新疆天山中东段和南天山西段地区2000年以来的以最小完整性震级(Magnitude of completeness,Mc)下限为基础的b值时空扫描图像,得到天山中东段和南天山西段两个不同区域的b值异常指标,研究结果表明:1天山中东段地区b值背景为0.705±0.004;南天山西段b值背景为0.583±0.003,略低于天山中东段b值背景水平。2 2003—2012年研究区内4次6级以上地震前,震中位置的b值多数处于低值状态,而震中附近区域其b值相对较高,反映出应力积累变化的主要方向。We obtained anomaly index of b-value in the central and eastern Tianshan, the western section of southern Tianshan of Xinjiang through the analysis of space-time scanned images for b-value based on the lower limit of minimum Mc from 2000. The results show that （1） The background value of b-value in central and eastern Tianshan is 0. 705 ± 0. 004, and that for the western part of southern Tianshan is 0. 583 ±0. 003, which is slightly below the background level of b-value in central and eastern Tianshan. （2） The b-values for the epicenter of the four earthquakes with magnitude above 6 in 2003 --2012 are principally in a low level before the earthquakes, but those of the region around the epicenter are relatively high, which reflect the main direction of stress accumulation changes.

关 键 词：B值 天山中东段 南天山西段 

分 类 号：P315.7[天文地球—地震学]