甘肃省玛曲县大水金矿“三位一体”找矿预测地质模型

通过对大水金矿地质作用、成矿构造、矿化蚀变和各种成矿信息的研究，总结了成矿地质体、成矿构造和成矿结构面、成矿作用特征标志，进而构建了"三位一体"成矿模式，为下一步找矿预测提供地质模型。确定大水金矿成矿地质体为晚三叠世的格尔括合花岗闪长斑岩及派生脉岩；成矿构造为北西向区域性断裂与晚期北东向、近南北向断裂系统控矿，成矿结构面主要为断裂构造、不同岩性的接触面、古岩溶构造等；成矿作用特征标志主要为硅化、赤铁矿化、褐铁矿化、碳酸盐化，成矿流体属于H2O-NaCl-CO2体系，流体气相主要成分为CO2和H2O，方解石、灰岩碳氧同位素及黄铁矿硫同位素表明成矿物质主要来源于岩浆。矿床形成于中浅成深度，金的成矿作用发生在相对还原的环境中。

The "trinity" geological model for ore prospecting and prediction of the Dashui gold mine in Maqu County,Gansu Province

Based on the "trinity" prospecting theory proposed by Ye Tianzhu et al., this paper summarizes the metallogenic geological bodies, metallogenic structures, metallogenic structural planes and characteristics of mineralization through the study of geological processes, metallogenic structures, mineralization alterations and various kinds of metallogenic information of the Dashui gold mine.Then the "trinity" metallogenic model was constructed, which provides a geological model for the next prospecting and prediction.The metallogenic geological body of the Dashui gold deposit is Late Triassic Geer inclusive rock mass and derived veins.The metallogenic structure is controlled by NW-trending regional faults, late NE-trending and nearly NS-trending faults.The main metallogenic structural planes are mainly fault structures, contact faces of different lithologies, and paleokarst structure.The characteristics of mineralization are mainly silicification, hematitization, limonitization and calcitization.The metallogenic fluids belonged to the system of H2O-NaCl-CO2, and the main components of fluid gas were CO2 and H2O.Calcite, limestone carbon and oxygen isotopes and pyrite sulfur isotopes indicate that ore-forming materials were mainly derived from magma.The deposit was formed in the middle-shallow depth, and the gold mineralization occurred in a relatively reduced environment.