Fixed-loop TEM surveying using the SQUID magnetometer for deep mineral exploration in a conductive area

Abstract The Baiyun gold deposits in the Qingchengzi ore concentration area have significant deep exploration potential. Transient electromagnetic (TEM) exploration is conducted to identify ore-bearing strata and ore-controlling structures in the mining area’s periphery. Previous tests have revealed that it is challenging to penetrate the conductive layer to obtain deep information using a conventional in-loop TEM method with an induction coil. Field data are acquired using a high-temperature superconductor (HTS) superconductive quantum interference device (SQUID) magnetometer with a fixed-loop configuration. The exploration results indicate that the SQUID TEM system can detect the distribution of ore-bearing strata, and the ore-control structures within deep formations. The paper explores two extension areas in the east and west of the Baiyun thrust nappe structural belt. The inversion results reveal that the Baiyun gold deposit is significantly compressed, with noticeable thrusts and faults. Since the thrust fault zone extends to the south stably, the lower section has a gentle dip angle favorable area for deep prospecting.