郯庐断裂带中南段前兆综合信息量地震预测方法研究*

(1.山东省地震局,山东 济南 250014; 2.河北省地震局,河北 石家庄 050021)

郯庐断裂带; 地震预测; 前兆综合信息量; 时空分析; 小波变换; EMD分解技术

Study on Prediction Method of Earthquake Precursor Synthetic Information along the Mid-south Segment of Tanlu Fault Zone
GENG Jie1,WANG Mei1,SHAN Lian-jun2

(1. Earthquake Administration of Shandong Province,Jinan 250014,Shandong,China)(2. Earthquake Administration of Hebei Province,Shijiazhuang 050021,Hebei,China)

Tanlu Fault Zone; earthquake prediction; precursor synthetic information; temporal and spatial analysis; wavelet transform; EMD decomposition technique

备注

结合地震前兆信息量综合数学表达式和小波变换、EMD分解技术,遴选郯庐断裂带中南段及其附近地区67个台点91个测项的连续性、可靠性较高前兆观测资料,多频域剖析前兆观测资料的变化特征、多层次挖掘地震前兆观测异常、最大程度地展示前兆群体映震效能。结果 显示,地震综合前兆信息量时序曲线,在ML≥5.0地震前会出现不同程度的高值异常(S时序≥0.1),一般高值异常出现1~6个月内,研究区有发生ML≥5.0地震的可能; 地震前兆信息量综合空间扫描的结果显示,未来的震中区多位于最早出现S≥0.2异常区的边缘区域,但异常区域的迁移规律性特征不明显,这可能与资料分析时段研究区内发生地震的震级较小及前兆台点的空间分布不匀有一定的关系。

Combined with the comprehensive mathematical expressions of earthquake precursory information,the wavelet and EMD decomposition technique,we selected the precursory observation data with good continuity and high reliability of 91 items at 67 stations in the mid-south segment of Tanlu Fault Zone and its adjacent area in order to analyzing the variation characteristics of precursory observation data in multi frequency domain,multi level digging into objective earthquake precursory anomaly and showed reflecting earthquake ability of group precursor. The results showed that there appeared the high value anomaly(Stime≥0.10)in different level before the ML≥5.0 earthquakes on the time series curve of earthquake synthetic information,and might occur ML≥5.0 earthquakes after high value anomaly appeared within 1~6 months in the study area. The spatial scanning results of synthesis precursory information showed that the future epicenter area located in the edge of the Swindow≥0.2 abnormal area where appeared earliest. But the migration regularity of anomaly region was not obvious,which may have a certain relationship with the earthquake magnitude was smaller and spatial distribution of precursory stations was unevenness in the study area in the process of analyzing data.