In order to construct the groundwater numerical simulation model, the study area was determined on the basis of the geological and hydrogeological conditions. Taking Feflow as operating platform, combining GIS with Surfer software, a study area of the structure of three-dimensional aquifer model was established, realizing the 3D visualization of a large area of the complex geological content. Combined with the hydrogeological conditions, three-dimensional geological structure of the model further generalization. The result showed that the aquifer of the vertical was generalized into the unconfined aquifer; based on the characteristics of lithology, structure, parameters and distribution of recharge and discharge in groundwater system, the study area groundwater system was characterized by isotropic saturated-unsaturated numerical flow model, and the equilibrium composition of the elements was analysed in study area, the partition of the aquifer hydrogeological parameters was divided, lay the foundation for groundwater numerical model simulation.
Groundwater is an important resource, it is used for variety of purposes in the inland river basins of arid western China. In recent years, the utilization ratio of surface water has been raised, the groundwater recharge rate from surface water has been reduced, and the aquifer depletion due to over-exploitation, which has led to the decline of groundwater levels and the degradation of eco-environments in the Shiyang River Basin, especially in Minqin. Therefore, the study on the groundwater levels change in recent years, as well as simulating and predicting groundwater levels in the future have gotten very important. The purpose of this study is to analyze the groundwater level variations of the study area. Basin on a conceptual groundwater model and observation groundwater level data, to establish the groundwater flow model by FEFLOW; simulated and validated the groundwater model. Finally the precision of model was evaluated. It was shown that the model could be used to predict the groundwater levels variation under different hypothesis conditions in Shiyang River Basin, which would provide the effective reference to the rational use and management of the groundwater.