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VTEM is a helicopter-borne Time Domain Electromagnetic (TDEM) system with concentric loop transmitter receiver geometry. The system utilises a coil as receiver, measuring the time derivative of the magnetic (dB/dt) field used to map and delineate sub-surface conductivities. However, extremely good conductors have very low dB/dt responses and are much better resolved by the induced magnetic (B) field. The B-field can either be measured directly or calculated by integrating the dB/dt response. This calculation of the B-field was recently introduced to the VTEM system. The additional benefit provided by the B-field response is illustrated over highly conductive mineral deposits. Data acquired over the Fox River Project and Caber deposits are presented as case histories and clearly demonstrate the benefit of continuing improvements in acquisition systems to provide increasing resolving capabilities for conductive targets.