The integration of geophysical techniques with hydrological investigation is frequently used for solving different geological and environmental problems including groundwater quality and exploration and seismic vulnerability assessment. In this research, the shallow geophysical techniques comprising of electrical resistivity profiling, vertical electrical sounding, and ground magnetic were used to identify the contaminated areas lying in the upstream and downstream of Almisk Lake in Jeddah. The chemical analyses of water samples collected from the wells located in the downstream and upstream areas were used to support these results as an increase in the total dissolved solids (TDS) shows a decrease in the resistivity value. The results of geophysical techniques and hydrochemical analyses show that the TDS values are significantly higher in the upstream area of dam than those of the downstream, which suggests that the contaminating source is lying in the upstream of the reservoir. Moreover, the dam was not completely successful to block the contamination because of improper base. The hydrochemical analysis and geophysical results clearly indicate that the groundwater is not suitable for drinking and irrigation purposes.

中文翻译：

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浅层地球物理和水文调查，以查明沙特阿拉伯吉达Wadi Bani Malik大坝地区的地下水污染

地球物理技术与水文调查的结合经常用于解决各种地质和环境问题，包括地下水质量，勘探和地震脆弱性评估。在这项研究中，浅层地球物理技术（包括电阻率分布图，垂直电测深和地磁）被用来识别吉达Almisk湖上游和下游的受污染区域。由于总溶解固体（TDS）的增加表明电阻率值降低，因此使用了从位于下游区域和上游区域的井中收集的水样的化学分析来支持这些结果。地球物理技术和水化学分析的结果表明，大坝上游地区的TDS值明显高于下游地区，这表明污染源位于水库的上游。而且，由于坝基不当，大坝无法完全成功地阻止污染。水化学分析和地球物理结果清楚地表明，地下水不适合饮用和灌溉。