中文摘要:内蒙古乌拉山金矿床是近年在我国北方发现的大型金矿床之一。矿床主要由赋存在太古界乌拉山群变质岩地层巾一系列石英一钾长石脉和石英脉组成。矿区范围内晚古生代一中生代花岗岩类分布广泛并且同金矿化具密切时、空分布关系。本文对乌拉山金矿床，大桦背花岗岩体和变质岩地层的硫、铅同位素比值进行了系统测定，并解释了不同地质体硫、铅同位素变化特征。研究表明：金成矿作用发生在240×106a，成矿物质主要来自大桦背花岗岩体及有关的岩脉，乌拉山金矿床形成过程中，亦有部分非岩浆物质混入。
Abstract:The newly discovered Wulashan K-feldspar-quartz and quartz vein gold deposit is located within Late Archean metamorphosed volcano-sedimentary sequences of Wulashan Group, and surrounded by a number of Late Paleozoic granitoid dikes and batholiths in southestern Inner Mongoiia. Sulfur isotope analyses of twenty-one sulfide(galena and pyrite)samples from auriferous K-feldspar-quartz and quartz veins，plagioclase amphibolites, gneiss and granitoid intrusions in the Wulashan area reveal that sulfur of the ore-bearing fluids was mainly derived from a mixed source of Late Paleozoic igneous and Arohean metamorphosed volcano-sedimentary rocks. Lead isotope data on plagioclase amphibolite define a correlation line with the slope corresponding to an age of 2498±76 Ma. In contrast, K-feldspar of the Dahuabei granitoid batholith is charaeterized by high content of radiogenic lead. On the plot, lead isotope data points of thirteen separated galena and pyrite samples from the auriferous vein system fall between the area of plagioclase-amphibolite and that of Dahuabei granitoid batholiths, and constitute a mixing line. The result of lead isotope study also indicates that Late Archean supraorustal rooks were the initial lead source for Dahuabei granitoid batholiths, auriferous K-feldspar-quartz veins and quartz veins. Both sulfur and lead isotope data show that lead, gold and other metal elements of the auriferous vein system mainly came from a mixed source of Archean metamorphosed volcano-sedimentaxy rooks and Late Paleozoic Dahuabei granitoid batholith which was probably derived from homogenized remelting of previously formed supracrustal rooks during Late Paleozoic tectonic events.
keywords:Wulashan of Inner Mongolia, gold deposit, sulfur and lead, isotopes, genesis of the ore deposit
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基金项目:国家青年自然科学基金(项目编号49000040)
引用文本：
聂风军，裴荣富，吴良士，张洪涛.1994.内蒙古乌拉山石英-钾长石脉金矿床铅和硫同位素研究[J].矿床地质,13(2):106~117.1994.Lead and sulfur isotope studies of the Wulashan K-feldspar and quartz vein gold deposit, southwestern Inner Mongolia[J].Mineral Deposits13(2):106~117
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