| The Saihan Obo Ag-Pb-Zn polymetallic mining area in the southern segment of the Greater Khingan Range is located in the Huanggangliang-Ganzhuer miao metallogenic belt. Given the region''s frequent tectonic and magmatic activities and its complex geological background, there is an urgent need to evaluate its deep prospecting potential. Building upon a systematic integration of historical exploration data, this study conducted specialized investigations into structural alterations. Isotope tracing and other experimental methods were employed to elucidate the sources of ore-forming materials and the evolutionary history of ore-forming fluids. Furthermore, by coupling multi-source data from geology, geophysics, geochemistry, and drilling, this study comprehensively explores the metallogenic regularities and prospecting potential of the district.The results indicate that the deposit formed in an Early Cretaceous extensional tectonic setting. Its formation was governed by a composite mechanism involving deep concealed small stocks providing heat and mass, strata serving as ore-hosting layers, and faults acting as conduits and traps. Ore-forming materials were predominantly derived from deep magmas with minor crustal contamination. The ore-forming fluids evolved from early magmatic water to late-stage meteoric water, suggesting that the deposit is of a medium-to-low temperature hydrothermal filling type.Spatially, over a hundred mineralized and altered bodies and 44 ore bodies have been delineated across the district, exhibiting typical characteristics of multi-directional mineralization, segmented aggregation, and structural control. Based on the coupling relationship between ore-controlling factors and anomaly information, a comprehensive prospecting indicator was established, centering on structural alteration zones, geochemical composite anomalies, and high-magnetic and medium-to-high polarization anomalies. Consequently, three priority target zones for future exploration were identified: the deep downward-dipping extension area of the Saihan Obo ore block, the medium-to-high temperature polymetallic metallogenic area in Liudigou, and the deep hydrothermal filling area in Xigou.These findings not only enrich the metallogenic theory of Ag-Pb-Zn polymetallic deposits in the southern Greater Khingan Range but also provide a crucial scientific basis and technical support for breakthroughs in deep prospecting in this region. |
