Full-3D Electrical Resistivity Tomography and Induced Polarization for Enhancing Deep Mineral Exploration

Induced Polarization (IP) and resistivity, expansively used in mineral exploration for decades, provide additional information on the spatial variation in lithology, chemistry, mineralization, moisture condition… Recent innovative development of cable less and autonomous geophysical equipment significantly enhanced deep resistivity and IP surveys in 2D and in 3D. Associated with an ergonomic processing chain, the Full-Waver system allows to record full-3D IP and resistivity block of data even in rough environment.

Simulations will be shown for comparing “pseudo 3D” and “full-3D” acquisition. Authors will also present two full-3D case studies carried out in Canada and Southern Africa dedicated for gold and diamond exploration. Despite a very weak IP contrast between the gold bearing ore body (2 to 3 mV/V) and the hosted rocks for the Canadian survey, results revealed a very clear anomaly down to 100 m depth. In Southern Africa, the survey helps to reveal two almost vertical conductive anomalies down to 300 m depth. Both are located over the magnetic analytic signal positive anomaly which leads to interpret it as two kimberlite pipes.