地震预测方法Ⅶ:水文地球化学方法

Earthquake prediction Ⅶ: geochemical method

地球化学法是地震预测方法中的一种,其主要是通过研究震前地球化学成分的异常变化,找出其与地震三要素的关系,进行地震预报.已有的地球化学法地震预测主要包括水化学异常、气体化学异常、土壤化学异常方法,由于水和气是组成岩石的介质,也是反映岩石受力变形和破裂的灵敏组分,因此水化学异常成为最常见的震前地球化学异常.常用的水文地球化学预测方法是监测地下水中的气体成分(氡、氢、氦等)、水质组分(B、F、Li和Sr等)、水电导率、水温及水位等化学和物理的异常,还有一些稳定同位素比值(He^3/He^4及Ar^(40)/Ar^(36)等)的异常变化,并对监测到的异常进行统计分析,同时结合岩石力学实验进一步得到水化学异常与地震"三要素"的关系,给出相关的地震预测意见.本文通过了解水文地球化学法地震预测的发展现状以及多个水文地球化学预测实例,分析总结多种水文化学异常信号的特征和测震结果,从物理和化学角度分析了水文化学异常形成机制,如岩石破裂机理、混合机理、振动机理、压溶机理等,并结合监测实例和影响水文地震预测的诸多因素分析与评价水文地球化学法地震预测的研究进展及发展前景.

Geochemical anomaly monitoring is one of the earthquake prediction methods,which is aim to find out the relationships between the earthquake ＇s three elements and the geochemical anomalies＇ changes,and then predict the earthquake.The existing geochemical methods can get the time、place and magnitude of the earthquake by studying the geochemical anomalies which include water chemistry,gas chemistry and soil chemical anomaly. Because the water and gas are the medium of rocks and the sensitive components to reflect the rocks deformation, the anomalies of hydro-geochemistry is the most common geochemical anomalies before earthquake. The common Hydro-geochemical prediction method monitors gas composition（radon,hydrogen and helium） in the groundwater,quality components（B,F,Li and Sr）,abnormal chemical and physical water conductivity, water temperature and water level etc.,there are some stable isotope ratios（He^3/He^4 and Ar^（40）/Ar^（36）） the abnormal changes of anomalies and the monitoring to the statistical analysis,combined with the relationship between the rock mechanics experiment,people can further get the relationships between hydro-chemical anomalies and earthquakes＇ ＂three elements ＂, then give the earthquake prediction opinions. This article includes the current situation of hydro-geochemical prediction and some hydro-chemical earthquake predictions,we analyze the characteristics and seismic results of several hydro-geochemical anomalies and the physical and chemical mechanism of water chemistry anomalies such as rock fracture mechanism, mixing mechanism, vibration mechanism,pressure solution mechanism, etc., then summarize the main anomalies feature, and evaluate the research progress and development prospect of hydro-geochemistry earthquake prediction method by combining monitoring examples and many factors affecting hydrological earthquake prediction.