Magnetic resonance sounding method applied to catchment study

Logs of the water content and relaxation times T and derived from Magnetic Resonance Sounding (MRS) measurements reveal the depth and thickness of subsurface water-saturated layers. Furthermore, using experience acquired through Nuclear Magnetic Resonance (NMR) logging (Hinedi, et al., 1993; Kenyon, et al., 1997), MRS data allow estimation of the effective porosity and hydrodynamic properties of aquifers. Once calibrated (definition of empirical constants C and for a given geology), MRS provides the effective porosity )z(w)z(*2)z(T1wpC )z(wC)z(wMRS=φ, (1) the permeability )z(T)z(wC)z(k12pMRS=, (2) and the transmissivity ∫=zdz)z(kTMRSMRS, (3)