LI Xia;FANG Zhang;JIANG Shi-xiong;MA Zhe;LI Li-jun;Key Laboratory of Groundwater Resources and Environment,Ministry of Education,Jilin University;State Grid Fujian Electric Power Co.,Ltd.;Jilin Geological Environmental Monitoring Station;

Yitong water source field;;vulnerability assessment;;PCA;;WOE;;assessment index system

The location of oilfield drilling must minimize its impact on groundwater and the surrounding environment. Taking the drilling site selection of Yitong County oilfield as an example,this paper used the Principal Component Analysis( PCA) and Weight of Evidence( WOE)to evaluate the groundwater vulnerability of the study area. On the basis of the inherent vulnerability of groundwater,3 indicators including land use mode,river distance and river density were added to establish the evaluation index system of groundwater vulnerability. Nitrate concentration was used for evaluation and verification,and the evaluation performance was compared with ROC curve. AUC values were 0.73 and 0.80,respectively. WOE's evaluation performance was better. Arc GIS was used to visualize the evaluation results. The results showed that the area with low vulnerability accounted for 25.57% of the study area,and the area with medium and high vulnerability accounted for69.85%. The oil field drilling site in the study area should be selected to avoid the overland,first-grade terrace,river and reservoir influencing area in the northeast. This study has reference value for the application of WOE to the evaluation of groundwater vulnerability,and provides a basis for oil field drilling site selection.