综合地球物理方法在水源区环境地质调查中的应用研究——以丹江口水库为例

Application research of integrated geophysical methods to environmental geology investigation in water source area:a case study on the Danjiangkou reservoir

丹江口水库以上的汉江流域是南水北调中线核心水源区,地下水调查是水源区环境地质调查的重要组成部分,笔者采用综合地球物理方法对地下水调查进行研究,研究结果表明:高密度电法在圈定隐伏断裂、地层岩性、岩溶发育区效果明显,反演电阻率可以优化垂直激发场计算;地面磁共振方法能够弥补高密度电法对地下水分辨率低的缺点,精细刻画地下水文地质特征,为构建水源区地下水格架提供参考依据.同时,笔者探索了高密度电法与地面磁共振方法的地球物理方法组合在水资源调查中的优越性.

Hanjiang catchment at up-stream of the Danjiangkou reservoir is the core headwater area for the middle-line project of south-to-north water diversion.Survey to underground water is an important part of environmental geology investigation in water source area.In this paper,integrated geophysical methods were used to study groundwater investigation.The results indicated that the high density electric method was an effective method in exploration of strata classification,karst development and buried fault.The inversion resistivity can optimize the vertical excitation field calculation.Overcoming the low resolution of the high density electric method in the detection of low resistivity,the Surface Nuclear Magnetic Resonance Method(SNMR)can directly prospect groundwater,and elaborate the underground hydrogeological features,which can provide reference basis for the construction of groundwater system in the water source area.In short,the advantages of the combination of high density electrical method and ground magnetic resonance method in water resource survey are explored.