2018年云南通海M_S5.0地震前视应力时空特征  

Temporal and Spatial Characteristics of Apparent Stress before Yunnan Tonghai M_S5.0 Earthquake in 2018

作　　者：彭关灵 赵小艳[1] 刘自凤 孔德育 PENG Guanling;ZHAO Xiaoyan;LIU Zifeng;KONG Deyu(Yunnan Earthquake Agency,Kunming 650224,Yunnan,China)

机构地区：[1]云南省地震局,云南昆明650224

出　　处：《地震研究》2018年第4期487-493,共7页Journal of Seismological Research

基　　金：中国地震局震情跟踪项目(2017010117);云南省地震局青年基金项目(201609)共同资助

摘　　要：利用云南数字地震台网资料,计算了2008年1月1日至2018年8月13日,2018年云南通海M_S5. 0地震震中100 km范围内3. 0≤M_L<5. 0地震的震源参数,得到参数间的定标律关系。为了扣除震级对视应力的影响,采用规准化视应力,获得了规准化视应力时间进程及空间分布图像。结果显示:地震视应力与震级、地震矩的皮尔逊相关系数分别为0. 63,0. 37,视应力与地震矩的相关性不显著;视应力标度率特征符合区域构造特征。通海M_S5. 0地震前15. 6个月,视应力和规准化视应力均出现高值异常,距离震中46 km,出现高值异常区域,说明该区域高视应力值对5级以上地震具有一定指示意义。Based on data of the Yunnan Digital Seismic Network,we calculated the focal parameters of 3.0≤M L<5.0 earthquakes within a 100 km radius of the epicenter from Jan.1,2008 to Aug.13,2018,and obtained several scaling law among the parameters.In order to deduct the effect of magnitude on apparent stress,we obtain the image of temporal process and spatial distribution by using the normalized apparent stress.The results show that the Pearson correlation coefficients between apparent stress and magnitude and seismic moment are 0.63 and 0.37,respectively,which may indicate that the correlation between apparent stress and seismic moment is not significant,and the characteristics of apparent stress scale rate conform to regional tectonic characteristics.During the 15.6 months before the Tonghai M S5.0 earthquake on Aug.13,2018,both of the apparent stress and normalized apparent stress appeared high value anomalies.The high value anomaly area appeared 46 km away from the epicenter,which indicated that the high apparent stress value in this area showed certain indication significance for the occurrence of M≥5.0 earthquakes.

关 键 词：通海地震 地震视应力 地震危险性 震源参数 

分 类 号：P315.727[天文地球—地震学]