**作者：**Lung-Chuan Lin ; Ting-Kuei Tsay ; Nien-Sheng Hsu**中文摘要：**Assuming an aquifer is homogenous and isotropic, discharge potentials and perturbation of the nonlinear interface boundaries are employed to derive a quasi-three dimensional and unsteady-state analytical solution for interfacial upconing of two liquids in an unconfined aquifer. To investigate the effects of pumpage, the position of the interface between the two liquids can be determined from the analytical solution. The present analytical solution of an isotropic aquifer is also extended to anisotropic cases. The analytical solution is a positive infinite integral type solution. Gauss-quadrature integration is used in the numerical computations. The present results of the interface upconing are verified through comparison with numerical solutions and experimental results. Very good agreement among these results is observed.**英文摘要：**--**中文關鍵字：**upconing, unsteady analytical solution, unconfined aquifer, saltwater and freshwater interface**英文關鍵字：**--