无越流承压含水层降落漏斗体积

epression cone of pumping well reflects the hydrogeological conditions of aquifer, such as hydraulic parameters and elastic storage for confined aquifer. Geometrical shape and volume of drawdown cone has important application value. According to Theis equation, during later period of pumping test in non-leaky confined aquifer, the relationship between drawdown and distance appears as straight line in s-lgr plots figure, and the relationship between drawdown and time appears as straight line in s-lgt plots figure. These characteristic are often used to calculate hydrogeological parameters and influence radius. Applying integration method, defined drawdown and distance as integration variable respectively, depression cone of pumping well in non-leaky confined aquifer was derived in this paper. Contrast to exact solution show that the depression cone within the influence radius calculated from straight line of s-lgr is a portion of the entire drawdown cone. The difference between the above two depression cone is pointed out also.