中国大陆自然电场的前兆机理与特征  

Possible Precursor Mechanisms and Characteristics of Natural Geoelectrical Field before Earthquakes in Chinese Mainland

作　　者：汪忠德[1] 

机构地区：[1]长江大学地球科学学院油气资源与勘探技术教育部重点实验室,湖北荆州434023

出　　处：《西北地震学报》2008年第4期360-365,共6页Northwestern Seismological Journal

基　　金：国家自然科学基金(40672071);中国石油天然气集团公司应用基础研究项目(05A10101);国家"973"煤层气项目(2002CB211709)

摘　　要：首先回顾了中国大陆地区震前自然电场前兆特征研究的发展历程。着重论述了震前自然电场的范围、形态、时间、与震级统计关系等前兆特征;指出震前自然电场产生的几种机理:过滤电场、扩散—吸附电位、电化学电位、机电转换效应以及压力作用下黄土层自然电位的变化;分析了自然电场是多种电信号叠加而成的一个综合电位,趋势性背景、季节性变化、地震信号和干扰因素都会引起岩石电阻率、土壤中溶液的溶解度和电离度、地下水的渗透条件、大地电场和自然电场的一系列变化。而面导电机制、体导电结构的变化造成宏观电阻率各向异性的增强并形成各测点间的电位异常,其形成机理和电磁响应特征的研究都能较好地认识地震前兆。The development caurse of research on the precursor characteristics of natureal geoelectric field before earthquakes in Chinese mainland is reviewed firstly. Then the range, figure and period of the field, as well as the statistical relationship with earthquake magnitudes are discussed. Some possible mechanisms of natural electric field before earthquake, such as infiltration electrical field, diffuse-adsorption potential, electro-chemical potential, electro-mechanical transformation effect and natural self-potential variety of loess under pressure, are pointed out. The natural electric field is a summating potential （SP） made of many signals, the trend background, seasonal variation, seismic signal and interference factors can all cause the change of rock resistivity, ionization and solubility of solution in soil, permeability condition of underground water, also the geoelectric field and natural electric field charge. The research on these mechanism of anomalies and characteristics of electromagnetic response will help us to understand the earthquake precursors.

关 键 词：地震 前兆特征 地电场 电磁响应 形成机理 

分 类 号：P319.11[天文地球—固体地球物理学]