Types of hydrogeochemical anomaly are influenced by age of groundwater,which is an indirect parameter of intense degree of water-rock reactions.The younger water, which means the water cycles underground in a short period,will not well reflect the changes of geochemical environment in crust,while the older water will not reflect the changes in time.From study of this paper,the following results are obtained: (1) The younger water or the older water often show the short-impending changes. (2) Changes of geochemical elements in the middle age water show the long-period trend one.The lasting time of the anomalies after earthquake is relative to the age of groundwater.%岩体中地下水的年龄对水化学异常类型有较大影响．地下水年龄也是水-岩反应剧烈程度的一个间接标志．年龄太小，反映地下水在岩体中贮留的时间短，不可能充分反映地壳内部地球化学环境的变化，从而可能降低其映震能力；反之，如果贮留时间太长，地下水就不能及时地反映出地壳内部地球化学环境的变化．年龄适中的地下水中的一些化学组分易于表现出完整的异常形态，而年龄太大或太小的地下水中的化学组分常表现出短临异常．震后效应的持续时间可能与地下水的年龄也有一定的关系．
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