Three-Coil EMI Multi-Frequency Sounding Devices in Near-Surface Applications

P051 THREE-COIL EMI MULTI-FREQUENCY SOUNDING DEVICES IN NEAR-SURFACE APPLICATIONS Abstract 1 The paper is devoted to the brief application feasibility study of three-coils multifrequency sounding device its advantages in comparison to devices that have two-coils. Influence of initial phase determination error into secondary field measurement accuracy was assessed. The estimation results of penetration depth are presented under the following models: conductive layer with non-conductive bottom half-space and conductive layer in resistive half-space. The estimated depths were compared with depth conventionally calculated using skin-effect approach. Several cases studies are included to prove the usefulness of multi frequency approach. Introduction E.V. BALKOV