A method to localize and characterize the sources of VLF tilt anomalies is proposed. It relies on the continuous wavelet transform computed with particular analyzing wavelets possessing remarkable properties with respect to potential fields. An example with a synthetic dyke model shows how the method allows to locate the top of conductive structures both horizontally and vertically. An application to real data acquired over a conductive dyke illustrates the robustness of the method with respect to noise.