Application of the time-frequency electromagnetic method and high-precision magnetic survey in the exploration of deep concealed ores

The Jinchanghe ore concentration area in the Baoshan block, Yunnan Province, is located in the northern part of the Baoshan-Zhenkang lead-zinc-copper polymetallic metallogenic belt. This area primarily hosts skarn iron-copper-lead-zinc polymetallic deposits. Previously, strong magnetic anomalies served as the primary geophysical exploration indicators for mineral prospecting in this area, while weak magnetic anomalies gained insufficient attention. Therefore, this study investigated weak magnetic anomalies in this area to reveal their promising potential for mineral prospecting. The time-frequency electromagnetic method and the high-precision magnetic survey were combined to verify weak magnetic anomalies, obtaining information on electrical and magnetic anomalies. Based on geological conditions, the joint inversion of multiple parameters was performed to delineate prospecting targets and precisely determine the spatial morphologies and occurrence locations of deep concealed ore bodies. Through borehole verification, the combined method achieved significant prospecting results. This study serves as an exemplary case for mineral prospecting in the deep and marginal parts of this area and also a reference for the exploration of similar deposits in other areas.