金山沟金矿床是新疆典型的陆相火山岩型金矿床之一，赋存于一套以粗面安山岩和玄武质粗面安山岩为主的早石炭世火山岩中，对火山岩的构造地质背景的研究是重建地质过程的关键。对矿区火山岩进行岩石地球化学特征和成矿物质来源、成矿温度等方面的研究和总结，进而探讨火山岩形成的构造环境与金矿床的成矿模式。地球化学特征表明，大多数火山岩的化学成分从钙碱性、高钾钙碱性变化到钾玄岩系列，属于富钠钙碱性安山质火山岩类，属于大陆边缘弧环境。同位素207 Pb/204 Pb的值与上地幔一致，S同位素也表明矿区火山岩为幔源岩，结合区域地质资料，认为金山沟金矿区出露的火山岩可能属于造山伸展期大陆边缘火山作用下的产物。包裹体测温数据和C、H同位素表明，金山沟金矿床成因类型为中低温浅成热液型金矿床。在以上研究基础上，结合成矿过程，将该矿床成矿模式总结为“两阶段三期次”的“两层楼式”。%Jianshangou Gold Deposit is one of the typical continental volcanic type gold deposits,hosted primarily in the late Carboniferous volcanic rocks,which mainly contain a set of trachyandesite and basaltic trachyandesite.The study on tectonic settings of the volcanic rocks is crucial for the reconstruction of the genesis.The paper studies and summarizes geochemistry of the deposit,the sources of metallogenic materials and mineralization temperature and other aspects of the volcanic rocks to discuss the tectonic setting of volcanic rock formation and mineralization pattern.Geo-chemical data indicate that the volcanic rocks range in composition from calc-alkaline,high-K calc-alkaline to shos-honite,which belongs to Na-rich calc-alkaline andesitic volcanic rocks and continental margin arc environment. 207Pb/204Pb isotope values are consistent with the mantle,S isotopes also show that volcanic rocks in the region are mantle source rocks.Combined with regional geological data, this paper considers that volcanic outcrops in Jinshan Gold Mine District may be the result of the extension of the continental margin orogenic volcanism.Inclusion tempera-ture data and C,H isotopes indicate that the genesis is medium-low temperature epithermal type gold deposit.In the a-bove study,based on the combination of the mineralization process,the metallogenic pattern is summed up as "two-stage three times,"the"two-story style.
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