中文摘要:内蒙东部的白音诺铅锌矿，是产于中生代火山断陷区的局部隆起环境中的锰钙矽卡岩型矿床，矿体主要分布于下二叠统大理岩与中生代中酸性超浅成/浅成侵入体接触带的锰钙辉石矽卡岩中，受层间破碎带控制，矿化体呈似层状。主要的铅锌矿石形成于400-220℃、盐度2.5-15 wt％NaCl当量、压力160×105-600×105Pa、酸性、还原环境。从早期的矽卡岩到晚期的硫化物-硫盐，水热流体的温度、盐度、压力逐步降低，矿液由偏碱性-弱酸性-酸性-弱碱性，介质由氧化-还原，fO2逐渐降低、fS2增高，金属矿物按氧化物-硫化物-硫盐的序列依次析出成矿。水热流体具异常低δ18O的特征，表明该矿床属中生代岩浆活化大气降水成矿的矽卡岩型铅锌矿床。
Abstract:The Baiyinnuo lead-zinc deposit of eastern Inner Mongolia is a calciomanganoan skarn type deposit existing in a partially uplifted environment of the Mesozoic volcanic fault depression. Veinlike and lenticular orebodies occur in skarn assuming rather stable stratoid bodies along the contact zone between Yanshanian hypergene-superhypergene intrusive bodies (granodiorite porphyry and quartz syenite porphyry)and Lower Permian marble or limestone. From southwest to northwest in the ore deposit, diopside member in the skarn pyroxene decreases whereas hedenbergite and johannsenite member increases, with the skarn-associated ore types being successively tin-bearing sphalerite-pyrrhotite, copper-zinc, zinc and lead-zinc(silver). Pyroxene associated with galena and sphalerite is rich in manganese, and its johannsenite member reaches 13.4-50.8％in content. There exist two metallogenic epochs, related respectively to granodiorite and quartz syenite porphyry. Each epoch might be further divided into three stages, i.e., skarn, quartz sulfides and sulfides-sulfosalts. In the skarn stage, manganhedenbergite and johannsenite formed obviously later than diopside and samite. Quartz-sulfide stage, the main metallogenic stage for lead-zinc ore, is characterized by galena, sphalerite, pyrrhotite, arsenopyrite, chalcopyrite and minor quartz replacing garnet and pyroxene. The sulfide-sulfosalt stage is noted for calcite, galena, sphalerite and bismuth-antimony sulfosalts. Horizontally, pyrrhotite, chalcopyrite and bismuth sulfosalts are commonly observed in the southwest part, while galena, sphalerite and antimony sukosalts tend to concentrate in the northeast. Fluid inclusion determination and calculation indicate that, from the early skarn stage to late sulfide-sukosalt stage, temperature, salinity, pressure and fO2 of hot fluids decreased steadily while fS2 increased gradually, with the hot fluid system changing from alkaline through acid to weak alkaline and the environment from oxidation to reduction. Ore minerals precipitated approximately in order of oxides-sulfides-sulfosalts, and lead-zinc ores formed in an acid and reducing environment with temperature 400-220℃, concentration 2.5-15 wt％(NaCl equivalent)and pressure 160×105-600×105Pa.The extremely low 18O values of garnet(3.70--9.65‰-SMOW), clinopyroxene (-6.00--12.46‰)and quartz(-2.78--6.080)are very peculiar. The 18OH2O (-11.17--13.75‰) and D(-118--120‰) values coincide with the hydrogen and oxygen isotopic composition of Mesozoic meteoric water of this region. This suggests that the Baiyinnuo lead-zinc deposit must have been a product of meteoric water activated by Mesozoic magma.
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引用文本：
张德全，雷蕴芬，罗太阳，鲍修坡，王胜利.1991.内蒙古白音诺铅锌矿床地质特征及成矿作用[J].矿床地质,10(3):204~216.1991.Geological Characteristics And Metallogeny Of The Baiyinnuo Lead-Zinc Deposit, Inner Mongolia[J].Mineral Deposits10(3):204~216
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