Abstract: Deep and peripheral resource exploration in operating mines is an important direction for future reserve increase and production expansion of mining enterprises. In response to the problems such as the shallow exploration depth,insufficient innovation in reserve increase exploration thinking,and the singleness of technical methods and means in operating mines,taking the Longqiao Iron Mine in the northern part of the Lüzong Basin,Anhui Province as the research object,through the systematic collection of geological,ore genesis and geophysical data in the mining area,a comprehensive geological-geophysical prospecting model was constructed,and the coupling relationship between orebodies and geological and geophysical fields was clarified. Based on this model,a large-scale gravity,magnetic and complex resistivity comprehensive exploration was carried out,and four anomaly areas with potential for mineral exploration were delineated. With the known borehole data and the density structure of the main geological bodies,the distribution range of magnetic bodies,and the low-resistance and highpolarization anomalous alteration zones revealed by the comprehensive exploration in the deep part of the mining area as constraints,and taking the physical properties of rocks and ores as the link,the 2. 5D gravity-magnetic joint inversion technology was applied to analyze the spatial distribution characteristics of geological bodies in the deep part of the mine,and potential favorable ore-forming spaces were identified,providing a basis for predicting the depth of ore bodies and the layout of boreholes. The verification boreholes ZKT04-3 and ZKT03-2 revealed multiple layers of iron-copper polymetallic mineralization and alteration,confirming that the application of comprehensive geophysical exploration of gravity,magnetism and electricity in operating mines can accurately delineate favorable mineral exploration targets,serving the reserve increase of mining enterprises. This provides an effective technical means for the implementation of deep and peripheral mineral exploration in operating mines in similar regions in the future,and has important practical significance. 

Key words: deep (peripheral) prospecting,gravity exploration,magnetic exploration,electrical exploration,Longqiao Iron Mine