Abstract: The Zaozigou gold deposit in Gansu Province is situated within the Xiahe-Hezuo area of the West Qinling Mountains. It represents a significant polymetallic gold deposit within the West Qinling metallogenic belt, exhibiting a high degree of mineralization that is closely associated with the regional tectonic activity. By examining the tectonic and geological characteristics of the mining area, with a particular focus on faults, joints, and scuff marks, the evolutionary sequence of the orecontrolling structures and the principal stress directions of the Zaozigou gold deposit have been determined. It is hypothesized that the tectonic evolution of the gold deposits in Zaozigou underwent three phases and six stages. In order to comprehend the distribution pattern and extent of the tectonic stress field within the mining region, a structural stress field analysis and a series of rock mechanics experiments were conducted, with the objectives of determining the mechanical parameters of the rocks and establishing a geologically logical mechanical model. A two-dimensional structural stress field numerical simulation of the Zaozigou gold mining area was conducted using the Finite Element Method (FEM), with the objective of predicting favorable sites for mineralization. The results demonstrate that the distribution of the tectonic stress field in the mining area is governed by the rupture. Furthermore, the maximum and minimum stress values in each period are predominantly concentrated at the periphery of the rupture. The intensity of stress is the primary factor in governing tectonic activity, with high stress areas exhibiting heightened structural activity and rock fragmentation, thereby creating pathways and sites conducive to mineralization. It is hypothesized that the two ends of the near-north-south faults and the intersection of the north-east and north-west faults represent optimal locations for mineralization.

Key words: tectonic evolution, tectonic stress field, finite-element method, numerical simulation, Zaozigou gold deposit