Author(s): A. Kovacs; P. Perrochet
Linked Author(s):
Keywords: Karst aquifers; Connected water systems; Hydrograph analysis; Recession coefficient; Parameter estimation; Groundwater modelling
Abstract: A new approach to characterising connected and karst water systems by means of hydrograph analysis has been developed. Two-dimensional analytical solutions for baseflow discharge facilitate a quantitative baseflow separation, and can be applied for the estimation of aquifer hydraulic parameters by means of hydrograph analysis. An extensive numerical study has been undertaken to verify the validity of analytical formulae. According to the analytical solution, baseflow can be expressed as a superposition of an infinite number of exponential components. Higher order components vanish at early stages of the recession process. This explains the imaginary exponential behaviour of baseflow. In reality, the recession coefficient calculated for each time step monotonically decreases over time, as confirmed by numerical model simulations. An analytical solution for diffusive flux from symmetric and asymmetric rectangular blocks has been developed.
Year: 2011