新疆哈密黑山金矿流体包裹体及Pb同位素特征

黑山金矿是在中天山地块中发现的第一个颇具规模的金矿。该矿床产于受沙泉子断裂的次级断裂控制的晚石炭世—早二叠世中酸性火山中。通过蚀变岩特征和流体包裹体实验确认黑山金矿的成矿流体为中低温(163～216℃)、低盐度(3.05%～5.09%NaCl_(eq))、H_2O-NaCl流体。黄铁矿中Pb同位素特征(~(206)Pb/~(204)Pb值为18.5365～18.7465,~(207)Pb/~(204)Pb值为15.6033～15.6294,~(208)Pb/~(204)Pb值为38.4035～38.6851)表明黑山金矿的成矿元素来源于俯冲带的岩浆作用。综合黑山金矿床地质与地球化学特征,认为黑山金矿是晚石炭世—早二叠世形成于造山带环境中与中酸性岩有关的浅成低温热液型金矿。

Fluid inclusions and Pb isotopic characteristics of Heishan gold deposit in Hami,Xinjiang

The Heishan Gold Mine is the first large-scale gold deposit discovered in the central Tianshan block. The gold deposit was produced in the Late Carboniferous-Early Permian volcano controlled by the secondary fault of the Shaquanzi fault. The ore-forming fluids of the Heishan gold deposit were confirmed to be medium-low temperature (163-216 °C), low salinity (3.05%-5.09% NaCl) and H₂O-NaCl fluid by alteration rock characteristics and fluid inclusion experiments. The Pb isotopic characteristics of pyrite (²⁰⁶Pb/²⁰⁴Pb value is 18.5365-18.7465, ²⁰⁷Pb/²⁰⁴Pb value is 15.6033-15.6294, ²⁰⁸Pb/²⁰⁴Pb value is 38.4035-38.6851). The study indicates that the ore-forming elements of the Heishan gold deposit are derived from the magma of the subduction zone. The geology and geochemical characteristics of the deposits in the Heishan gold deposit are comprehensively analyzed. It is believed that the Heishan gold deposit is a paleogenic low-temperature hydrothermal gold deposit associated with the medium-acid rocks formed by the Late Carboniferous-Early Permian in the orogenic belt.