中文摘要:银洞沟铅锌-银矿床产于一火山穹窿核部。矿床的矿化过程先后由银矿化期和铅锌矿化期组成。前者分三个矿化阶段,后者分两个矿化阶段。矿床地质特征表明,矿床形成和火山穹窿核部的流纹质次火山侵入岩具有密切成因联系。本文较全面、系统地论述了该矿床的微量元素、同位素(Pb、H、O、S、C)、流体包裹体地球化学特征、矿床形成的化学热力学条件。在此基础上,从火山作用和成矿作用的地质背景、时代和相互关系,成矿物质来源,成矿物理化学条件及成矿机理三个方面探讨了矿床成因。作者认为本矿床形成于1 3亿年左右,成矿物质来自上地幔或下部地壳的次火山中-低温热液。
Abstract:The Yendonggou lead-zinc-silver deposit, whose ore-forming process can be divided into the earlier silver mineralization period composed of three stages and the later lead-zinc mineralization period made up of two stages, occurred at the center of a volcanic rise and was closely related to the supergene intrusion of rhyolite. Detailed geochemical researches demonstrate that it is a low-medium temperature subvolcanic hydrothermal deposit. The isotopic evidence (Pb, S, O, H, C ) yields the following conclusions: 1. The deposit has an age of 1300 Ma. 2. The ore-forming metals and sulfur came from the upper mantle or from deep part of the crust. 3. The ore-forming fluids of earlier mineralization period were derived from mixture of meteoric and magmatic water while the fluids of later mineralization period merely from meteoric water. According to the data of fluid inclusions and the thermodynamic analysis, the temperature of silver mineralization ranges at least from 180℃ to 320℃ and the salinity of ore-forming fluids, 5 to 15 wt.% equiv.; the temperature of lead-zinc mineralization, 130℃ to 280℃, the salinity, 2 to 8 wt. % NaCl equiv., and the ore-forming pressure, about 200×1015 Pa.; the fugacity of the two periods, 10-12 atm. to 10-38 atm., and pH, approximately 4.5 to 5.6.
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刘丛强.1987.银洞沟铅锌-银矿床的地球化学特征及其成因分析[J].矿床地质,6(4):53~61.1987.Geochemistry And Genesis Of The Yendonggou Lead-Zinc-Silver Deposit[J].Mineral Deposits6(4):53~61
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