唐山地区地震视应力时空变化特征  

Temporal and Spatial Variations of Apparent Stress in Tangshan Area

作　　者：周依 马旭东 王想[2] ZHOU Yi;Ma Xudong;WANG Xiang(Hebei Hongshan National Observatory on Thick Sediments and Seismic Hazards,1540 West-Quanbei Street,Xingtai 054000,China;Hebei Earthquake Agency,262 Huaizhong Road,Shijiazhuang 050021,China)

机构地区：[1]河北红山巨厚沉积与地震灾害国家野外科学观测研究站,河北邢台054000 [2]河北省地震局,石家庄050021

出　　处：《大地测量与地球动力学》2024年第10期1059-1063,共5页Journal of Geodesy and Geodynamics

基　　金：河北省地震科技星火计划(DZ2024112100001,DZ2024111400001,DZ2022060600011)。

摘　　要：利用唐山地区2009年以来的地震波形资料,基于Brune圆盘模型反演得到105个M_(L)≥3.0地震的震源参数。根据震源参数定标关系可知,各参数与震级均呈现较好的正相关性;视应力值在0.29×10^(5)~18.97×10^(5)Pa之间,平均值为3.08×10^(5)Pa。视应力时空变化特征分析结果表明,随着唐山地区中强地震的发生,视应力出现显著的震前上升-震后下降的变化特征,反映了区域应力场的演化过程。丰南M_(S)4.5和唐山M_(S)5.1地震不仅发生于高视应力集中区边缘,而且处于归准化视应力高低值分界附近,推测高视应力和低视应力的过渡区可能是中强地震孕育的场所之一。Based on seismic waveform data since 2009 in Tangshan area,the Brune model was employed to determine the apparent stresses of 105 earthquakes with M_(L)≥3.0.The calibration relationships of source parameters indicates that the source parameters are positively correlated with the magnitude.The apparent stress value is between 0.29×10^(5) to 18.97×10^(5) Pa,and the average value is 3.08×10^(5) Pa.The temporal and spatial variation of apparent stress shows that the apparent stress increased before the moderate-to-strong earthquake and decreased after it,which accurately reflects the state of the stress field in the hypocenter region.The Fengnan M_(S)4.5 and Tangshan M_(S)5.1 earthquakes not only occurred at the edge of the high apparent stress area,but also near the boundary high and low normalized apparent stress.We speculate that the transition zone between high and low apparent stress may be one of the places where moderate-to-strong earthquakes occur.

关 键 词：唐山地区 视应力 时空变化特征 

分 类 号：P315[天文地球—地震学]