Abstract:
The southern Chongyang area is located within the Middle−Lower Yangtze River W−Au polymetallic metallogenic belt, exhibiting favorable gold mineralization potential. The area is dominated by Cambrian−Ordovician strata. Geological exploration and sample analyses indicate that Au anomalies are primarily hosted in the interlayer fracture zones of the upper member of the Lower Ordovician Liuzuiqiao Formation, which conformably contacts the silty shale of the overlying Ningguo Formation. A distinct structural alteration zone is developed between the two formations, characterized mainly by pyritization, arsenopyritization, and sideritization. Notably, elements such as Au, As, and Sb are significantly enriched, reflecting a typical geochemical association of Carlin-type gold deposits. Regionally, large-scale NE-trending faults are well-developed and serve as the principal rock- and ore-controlling structures. Due to marked competence contrasts between limestone and silty shale, silty shale with limestone lenses, and sandstone, bedding-parallel sliding has occurred during later geological evolution, creating favorable pathways for the migration of ore-forming fluids and the formation of ore-conducting channels. Regional anticlinal axes and associated structures (joints and cleavages) provide additional settings for gold enrichment and material exchange. Comprehensive studies suggest that Gaojian Gold Deposit is a Carlin-type gold deposit controlled by interlayer fracture zone. Deep-seated concealed intrusions and ore-forming fluid sources are key drivers of mineralization. Future ore-prospecting breakthroughs should focus on exploring deep magmatic activity and further validating the Carlin-type mineralization model, which will provide important guidance for delineating gold exploration targets in similar areas of southern Hubei.