Stage Division and Ore-bearing Evaluation of Fault Tectonic in the Longmendian Silver Deposit, Luoning, Henan Province

The Xiong'ershan is one of the most important gold, silver and molybdenum producing areas in China, and most of the regional industrial orebodies are controlled by the faults. This study takes the Longmendian silver deposit as an example, the occurrences of K1 and K6 ore bodies are statistically analyzed by StereoNett software based on the Anderson model. Combined with the history of regional geological evolution, the fault structure in this study area has been divided into four stages:Stage I is NE and NW faults formed by near S-N compressive stress, and NNE-derived fractures; Stage Ⅱ is metasynthetic structures formed near the S-N extensional environment, the secondary NE-NNE formed in the first stage filled with quartz veins to the faults, and it is accompanied by the precipitation and enrichment of hydrothermal fluids to form industrial ore bodies, and some NE-NNE and NW fractures are mineralized; Stage Ⅲ in NE-NEE post-mineral structure formed by compressive stress, partially developed NNE and cut pre-NE fracture; Stage IV is post-mineral structure formed by NWW compressive stress-NW left-sliding slide fault. It is concluded that the NNE fault formed in the stage I has good ore-bearing property, which is of guiding significance for later prospecting.