Stochastic Analysis of Oscillatory Hydraulic Tomography

This study investigates the role of periodic excitations with different frequencies to estimate highly parameterized hydraulic transmissivity and storage coefficient fields in heterogeneous aquifers using the cross-correlation between hydraulic parameters and aquifer head response. The analysis suggests that heads induced by pumping with different frequencies carry the same information about the heterogeneity. This result is then verified by estimating the parameters in a synthetic heterogeneous aquifer under these excitations. For assuring the statistical significance of the results, Monte Carlo experiments for estimating the parameters with these excitations are conducted. Finally, the comparison between the resolution of the estimates, the ergodicity of estimate, the convergence speed of the algorithm, and the tolerance of noise under excitation with single frequency and excitation with multiple frequencies are discussed.