福建地区流体台网对台湾7级地震有效映震因素分析

The analysis of effective earthquake reflecting factor of Fujian fluid net to Taiwan earthquakes with M_S7.0

通过对福建流体台网运行现状的分析,选择了4个分别代表温泉、热水井和冷水井,且这些观测点位于构造断裂带及构造断裂带交汇处,含水岩性为中酸性侵入岩和火山岩,水点类型为基岩裂隙泉和自流井。以资料连续性较好的模拟观测点作为研究对象,分析这些观测点对1990年以来台湾历次7级以上地震的前兆异常对应特征,讨论了映震能力及其有效映震因素。结果表明,福建流体台网前兆异常对台湾7级以上地震有较好的映震效能;观测点的映震能力在一定程度上取决于水点所处的构造位置;映震的灵敏度在一定程度上取决于水点的水文地球化学背景条件。

Through the analysis of the present condition of Fujian fluid net, four water sta tions, respectively representing hot springs or hot water wells as well as cold water wells are selected as study targets. These water stations are located right on the structural fault zone or the tectonically intersecting zone, the rocks containing water are intermediate acid intrusive rock or volcanic rock, the type of the stations is the basic rock fissure spring or flowing well. Analyzing the precursory characteristics of anomaly of these observational stations to Taiwan earthquakes above Ms7. 0 since 1990, the ability to reflect the earth quake and the factor of indicating earthquake of this monitoring net are discussed. The conclusions is that the anomaly of underground water of Fujian fluid net to Taiwan earthquakes above Ms7.0 have the stronger earthquake--reflecting ability; The earthquake-reflecting ability of water station depends on the structural position, where the water stations are located in a certain degree; The sensitive composition reflecting earthquake in a certain degree is decided by the hydro geochemical background of water stations.