珲春7.0级深震地下流体前兆的动态特征研究

Study on the dynamic features of subsurface fluid precursor before Huichun M7.0 deep earthquake

论述了珲春7.0级深源地震地下流体中期、短期、临震、震时、震后异常,分析了地下流体异常特征。认为其时间展布具有阶段性,配套性和集中性,异常出现的时间与震中距密切相关,其空间展布具有迁移性,中期异常由外围向震中收缩,其速率很小,进入短期阶段,速率迅速加大。临震异常由震中向外围发散,其速率加大到剧增。此即为我们捕捉岩石变形临失稳阶段提供信息,是经验性预报向物理预报过渡的一种尝试。本文尚对地下流体异常与地震构造的关系,地下流体异常的场兆、源兆特征进行了讨论。

The characteristics of medium term, short term and imminent anomalies in subsurface fluid before Hunchun M7.0 deep earthquake are analyzed. The distribution of anomalies has phasic variation and centrality. The occurrence time of anomaly is related to the epicentral distance. In medium term, the anomalies concentrate from outside to the epicenter, and its rate is very slow; when in short term stage, the rate becomes large. In imminent stage, the anomalies diffuse from the epicenter to the outside, and its rate rapidly increases.