Geophysical investigation of the Xiarihamu Cu-Ni-Co deposit and its surrounding areas in East Kunlun, Qinghai Province

The Xiarihamu copper-nickel mine ranks second in scale domestically, following only the Jinchuan copper-nickel mine. By conducting physical property measurements and transient electromagnetic method effectiveness tests in the mining area, the central position of the No. 1 rock mass was determined using three-component transient electromagnetic technology. Additionally, the use of borehole transient electromagnetic methods ruled out the possibility of a low-resistivity good conductor on the north side of the No. 1 rock mass at depth, providing favorable technical support for drilling work. Furthermore, in peripheral exploration, the combination of transient electromagnetic and magnetic surveys revealed the deep-seated trend of peripheral lead–zinc deposits, thus providing guidance for subsequent exploration efforts. • Through TEM validity experiments in mining areas, geological personnel’s understanding of the occurrence of ore-bearing rock masses has been revised. • The occurrence and boundary of the No.1 rock mass containing ore were effectively determined through the ground and underground transient electromagnetic measurements. • In the peripheral exploration work, the prospective mineralization areas of peripheral lead–zinc deposits were delineated through surface and underground transient electromagnetic waves. Physical properties and geophysical measurements were conducted on the Xiarihamu copper-nickel mining area and its surrounding areas in the East Kunlun region of Qinghai Province. This work summarizes the physical characteristics of the mineralized strata in the mining area and delineates the exploration prospects within and around the mining area. These findings provide a foundation and direction for future prospecting efforts. By conducting targeted experiments on the known profiles within the mining area using the transient electromagnetic (TEM) method, as well as conducting TEM profile measurements in the covered regions, our geological understanding of the ore-bearing rock mass has been enhanced. Consequently, prospective areas for deep mineral exploration within the mining area were identified, establishing a solid basis for future deep exploration efforts. In the periphery of the mining area, prospecting was based on anomaly verification from high-precision magnetic surveys, supplemented by the interpretation of ground and borehole transient electromagnetic (BTEM) surveys. It was inferred that the electrical and magnetic anomalies in the periphery originate from a common source. The prospecting results indicate that the high-precision magnetic anomalies in the peripheral areas are related to the orientation of the anomaly center and the characteristics of the electrical and magnetic anomalies. The northern extension of the existing magnetic anomaly has been identified as the primary direction for future prospecting efforts.