城市地块土壤重金属污染的感应电磁法与高密度电阻率法分析

联合采用感应电磁法和高密度电阻率法对城市污染地块土壤环境进行测评，以华南某典型重金属污染地块为研究对象，通过对重点区域开展电磁扫描，在二维空间刻画出潜在污染区域，然后利用高密度电阻率法进一步刻画污染深度和垂直污染范围. 研究区废渣堆放位置和污水处理池下游的0~8.0 m、3.5~10.5 m深度范围存在多个电阻率小于8 Ω·m的低电阻异常区(疑似重金属污染区域)，其中低电阻异常区的砷(As)和铅(Pb)污染严重，最大质量分数分别达1 170.00、2 700.00 mg/kg. 结果表明:感应电磁法和高密度电阻率法联合探测污染地块重金属污染的方法具有较强的可行性，能初步表征重金属污染物的空间分布状况，进而指导后续靶向钻探布点和采样，为污染地块的精准化土壤污染状况调查与修复提供科学依据.

Analyzing Heavy Metal Pollution with the Induction Electromagnetic Method and the High-density Electrical Method in Urban Land

The electromagnetic method and the high-density electrical method were applied to the investigation of soil environmental of urban polluted land. A typical heavy metal-contaminated site in South China was taken as the research object. The induction electromagnetic method was used to preliminarily screen and describe the contaminated areas in two dimensions. The high-density resistivity method was used to further detect the pollution depth characteristics and vertical pollution range. There were many abnormal areas with low resistance less than 8 Ω·m (suspected heavy metal pollution area) in the soil layer of 0~8.0 m and 3.5~10.5 m depth in the waste dumping area and the downstream area of sewage treatment tanks. The low resistance anomaly areas were serious polluted by heavy metals such as As and Pb, and the maximum contents were 1 170.00 mg/kg and 2 700.00 mg/kg respectively. The results show that it is feasible to detect the heavy metal pollution in the polluted land with the combination of the induction electromagnetic method and the high-density electrical method. They can be used to preliminarily characterize the spatial distribution of heavy metal pollutants and then accurately guide the subsequent drilling location and sampling to provide scientific basis for the accurate investigation of soil pollution and remediation of contaminated sites.