2007年宁洱6.4级地震序列视应力研究

英文篇名：Apparent Stress of the 2007 Ning'er,Yunnan,M_S6.4 Earthquake Sequence
中文刊名：地震研究
英文刊名：Journal of Seismological Research
作者：钱晓东 ; 李琼 ; 秦嘉政
英文作者：QIAN Xiao-dong1 LI Qiong2 QIN Jia-zheng1 (1. Earthquake Administration of Yunnan Province ; Kunming 650224 ; Yunnan ; China) (2. Department of Geophysics ; School of Resource Environment and Earth Science ; Yunnan University ; Kunming 650091 ; Yunnan ; China)
中文关键词：宁洱地震 ; 地震序列 ; 视应力 ; 地震辐射能
英文关键词：Ning'er earthquake ; earthquake sequence ; apparent stress ; earthquake radiation energy
出版日期：2007-10-15
机构：云南省地震局,云南大学资源环境和地球科学学院固体地球物理系,云南省地震局昆明650224,昆明650091,昆明650224
年：2007
期：04
出版单位：地震研究

摘要

利用云南省区域数字化观测资料,估算了2007年宁洱6.4级地震序列视应力,结果表明:①宁洱震区视应力在空间分布上明显呈NE向展布,视应力较高的地震大都分布在地震辐射能较高的地区;②宁洱6.4级主震发生的前4天,平均视应力为0.95MPa,主震发生4天以后,平均视应力为0.27MPa,恢复到云南平均背景应力水平;③视应力随拐角频率的增加而减小,大致呈负相关:lgσa=-0.36f+0.37,视应力与震源深度之间未发现明显的依赖关系。
We calculated the apparent stress of the 2007 Ning'er,Yunnan,MS6.4 earthquake sequence using the data recorded by Yunnan Regional Digital Seismic Network. The result shows:(1) the apparent stress distributes obviously along NW-direction in the Ning'er earthquake area,and the earthquake with high apparent stress mostly locates in an area with high earthquake radiation energy;(2) within 4 days after the main shock,the average apparent stress is 0.95 MPa,after that it is 0.27 MPa,come back to the average apparent stress level of Yunnan;(3) the apparent stress reduces with increasing corner frequency,generally is negatively correlative:lgσa=-0.36f+0.37,and obvious dependent relation has not been found between the apparent stress and the focal depth.

引文

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