Abstract:
The low-temperature hydrothermal metallogenic province in the Youjiang Basin is characterized by Carlin-type gold deposit and vein-type antimony deposit. However, the mineralization links and the similarities and differences between the Au and Sb mineralization processes require further systematic analysis. To address this issue, this paper built upon extensive previous research to analyze and summarize the fluid sources and evolution, as well as the enrichment and precipitation mechanisms of the Au−Sb mineralization process. On this basis, the paper revealed the similarities and differences in their mineralization processes. The analysis indicates that the initial ore-forming fluids for both gold and antimony originated primarily from deep sources (magmatic/metamorphic). During the mineralization process, these fluids likely underwent varying degrees of dilution due to the involvement of basin fluids and meteoric water. Moreover, significant differences exist in the mineralization mechanisms of Au and Sb. Gold mineralizing fluids are predominantly weakly acidic to neutral, with fluid-rock interaction serving as the primary mineralization mechanism. In contrast, Antimony mineralizing fluids are dominantly acidic, where changes in oxygen fugacity, temperature, and pH induced by fluid mixing are the main mechanisms for stibnite precipitation. Consequently, it is proposed that the mixing of fluids from different sources during the evolution of ore-forming fluids, along with the distinct mineralization styles of gold and antimony, may be the main controlling factors for the differential mineralization of Au and Sb. Based on the Au−Sb metallogenic model, it is proposed that the extensional structural system formed during the Yanshanian period serves as a favorable locus for antimony mineralization. The results provide theoretical support for the regional resource potential assessment during the "15th Five-Year Plan" period.