RELATION BETWEEN ANISOTROPIC TRANSMISSIVITY AND AZIMUTHAL RESISTIVITY SURVEYS IN SHALLOW, FRACTURED, CARBONATE FLOW SYSTEMS

In an investigation of a near-surface, fractured, carbonate ground-water flow system, the axes of the apparent resistivity ellipse determined from an azimuthal resistivity survey were shown to coincide with both the ellipse of depression during an aquifer test, and the eigenvectors of the transmissivity tensor determined from the aquifer test analysis. Thus, for such relatively shallow, fractured flow regimes, azimuthal resistivity surveys may be a useful methodology for determining the principal directions of transmissivity prior to conducting anisotropic pumping tests, and thus aid in designing the emplacement of observation wells.