鲁豫交界地区豫01、11井和鲁27井等3口地震观测深井的水位于2006年后出现了准同步的异常下降变化,下降幅度3～12m不等。经调查落实,发现该地区近年来地热开采活动日益增强,开采量逐年增大,并且开采层与异常井水位观测层同属于奥陶系热储层。为此,本文依据聊城-兰考断裂带附近区域的水文地质构造特征,建立了三维地下水流动模型,基于周边地热开采量数据和相关含水层参数,运用有限差分方法计算了地热开采所引起的区域水位降落漏斗,并分析了水位下降异常的时间演化和空间分布特征。结果显示,聊城-兰考断裂带附近区域自1995年开始地热开采活动以来,其逐年增加的地热开采量与地震观测井水位的下降幅度之间存在较好的对应关系,分析认为鲁豫交界地区3口深井水位的准同步异常下降与周边地热开采活动有关。

The water levels in deep wells of YU01, YU11 and LU27 have continued to decline almost at the same time since 2006, and the decreases range from 3m to 12m. The three wells are located in the border area of Shandong and Henan. The investigation reveals that there are some pumping wells for geothermal mining, and the mining is gradually increased. We also find that the observation layer of wells with water level decreasing is the same aquifer layer which is pumping now, and the heat reservoir belongs to Ordovician. According to the hydrogeologieal tectonic characteristics of the area nearby Liaocheng-Lankao fault, we set up a three dimensional groundwater flow model based on the surrounding geothermal data and related aquifer parameters. Water landing funnel caused by geothermal mining was calculated using finite difference method, and the distribution characteristic of drawdown was analyzed. The result shows that the decline of water level was related to the pumping for geothermal mining. In areas nearby Liaocheng-Lankao fault zone, geothermal mining, which has increased year by year since 1995, has a good corresponding relationship to the decline of water level in deep wells.

“十二五”国家科技支撑计划项目（2012BAK19802-04）及中国地震局青年震情跟踪小组共同资助