As an example, the result of the single frequency analysis of a SIP sounding (0.366Hz) is presented.  The measured apparent resistivity and phase values are inverted by using a stronger horizontal weighting and fixed layer boundaries, taken from geological information. On the basis of the resulting models (real and imaginary conductivity model) we calculated hydraulic parameters: the porosity is derived by applying a modified Archie approach (Börner et al. 1996). For calculating K we used the relation between specific inner pore surface and imaginary conductivity (Slater & Lesmes 2002), while the second approach includes in addition porosity (Börner et al. 1996).  Moreover, SIP lab results and further lab measurements to determine porosity (by bulk density) and K are included. A precise description of the presented methods and results can you find in Holland et al. (2010).

The used approaches produce mostly good results, which agree with hydraulic properties of the material of the two middle sandy aquifers (porosity of 35 – 40%, K-values of 10*e-4 m/S). However, we still have problems with porosity calculation due to strong lateral and horizontal variations of the fluid conductivity.

References

Börner, F.D., Schopper J.R. and Weller, A. 1996: Evaluation of transport and storage properties in the soil and groundwater zone from induced polarization measurements. Geophysical Prospecting  44, 583-601.
Slater, L and Lesmes, D.P. 2002: Electrical-hydraulic relationships observed for unconsolidated sediments. Water Resources Research 38, 31-1 to 31-13.

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