新疆天山地区b值时空变化特征

摘要/Abstract

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, M_c)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。

关键词: b值, 天山中东段, 南天山西段

Abstract: 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.

Key words: Variation of b-value, Central and eastern Tianshan, Western part of southern Tianshan

中图分类号:

P315.7

张琳琳, 唐兰兰. 新疆天山地区b值时空变化特征[J]. 地震, 2015, 35(3): 93-101.

ZHANG Lin-lin, TANG Lan-lan. Temporal and Spatial Variations of b-value in Tianshan, Xinjiang[J]. EARTHQUAKE, 2015, 35(3): 93-101.

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