Application of High-Precision Magnetic Measurement in the Exploration of Deep Fluorite Deposits in Ore Concentrations

The Heyu ore-concentrated area in western Henan, situated within the East Qinling metallogenic belt, represents a strategic fluorite resource base currently confronting severe challenges of reserve depletion. Given this critical status, this study focuses on enhancing exploration of concealed fluorite deposits through an innovative aeromagnetic approach. Prioritizing aeromagnetic surveys across 280 km2 of rugged terrain achieved 100% coverage, demonstrating cost-efficiency in regional-scale exploration of fault-controlled fluorite systems. By systematically analyzing mineralization mechanisms and integrating processed magnetic data with geological constraints, we characterized magnetic anomaly patterns specific to fluorite-bearing structures. Key findings include: distinctive “low-density, low-magnetic” signatures of fluorite deposits (2.42 g/cm3, 15.57 × 10−5 SI) contrasted sharply with host granites (2.58 g/cm3, 2612 × 10−5 SI); identification of two deep-seated prospecting targets (Y-1 and Y-2) through residual anomaly analysis, spatially correlating with fault intersections; and successful borehole validation revealing 11.5 m-thick fluorite zones at 300–500 m depths. The established geological–geophysical model provides dual functionality: enabling precise delineation of deep-seated exploration targets, and offering actionable guidelines for sustainable resource development in ore-concentrated areas. This work pioneers a technical pathway for fluorite exploration in complex terrains, underscoring geophysics’ indispensable role in deep mineral targeting while setting a benchmark for analogous metallogenic provinces.