首都圈地区前兆台址地质条件对其映震能力影响的统计分析

本文系统收集了首都圈地区38个形变类观测台、29个地下水类观测井与15个电磁类观测台的地质—水文地质条件,并根据1976—1989年间5个中强地震前的58个台项的异常,逐项统计分析了台址地质—水文地质条件对其映震能力的影响。得到的认识是,影响地形变类台站映震能力的主要地质条件是构造单元、邻近断裂的走向、距离、活动时代与台基地层岩性;影响地下水类观测井映震能力的主要条件是构造单元、邻近断裂的走向、距离、部位、井深、含水层的地层岩性与地下水类型;影响地电磁类台站映震能力的主要条件是构造单元、新生界盖层的结构与厚度、表土岩性、基底岩性与壳内高导层顶面埋深等。

The Geological Conditions of Precursor Observation Station and Its Influence on Reflective Capacity of Earthquake Anomaly in the Capital Area

In this paper,the geologic and hydrogeological conditions of 38 observation stations of crustic deformation, 29 observation wells of groundwater and 15 observation stations of elctro-magnetic precursor are systematically collected. On the basis of 56 anomalies before 5 middle and strong earthquakes, occurred during 1976-1989 ,the influence of geologic and hydrogeological conditions on reflective capacity of station or well are analysed one by one. It is the conclusion that the conditions of influencing reflective capacity of stations for crustic deformation are the tectonic unit,the strike,distance,active time of the fault near station and the lithelogic property of the site. The conditons for groundwater are the tectonic unit,the strike,distance,position of the fault near wells,the depth of the well and lithologic property and groundwater type of the aquifer. The conditions for electro and magnetic precursor are the tectonic unit,the composition and thickness of Cenozoic group,the soil type near the surface and the lithologic property under Cenozoic group and the depth of the layer with high electric conductivity in the earth crust.