【摘要】 水化群体异常的演化趋势与地震活动密切相关。中强地震前，水化异常变化速率值呈现“增长一地震＂的普遍规律。在月、旬和五日等不同时间尺度上的水化群体异常演化图式，具有显著的自相似性和可重复的特征．并可分别作为地震的短期、短临和临震前兆标志与发震时间的判别依据。异常变化速率分析法的预测效果良好，具有实用价值，但尚需在今后的预报实践中进一步检验与完善。更多还原

【Abstract】 The evolutionary trend of hydrochemical colony anomaly is closely related to seismicities. Before moderate strong earthquakes, the variation rate of hydrochemical anomaly showed the common regular patterns as"increase-earthquake occurrence". Abnormal evolutionary patterns of hydrochemical colony in different time scales as in month, ten days, five days and so on are of remarkable self-similarity characters and repeatability, which can be taken as the criterions of precursory index for the forthcoming, short-term and impending earthquaks and occurrence time prediction, respectively. Althouqh the analysis method of abnormal variation rate displaced a better predicting effect and got some practical values, it still waits to be tested and perfected in future.更多还原