中文摘要:文章在总结前人研究成果的基础上,提出新疆北部古生代浅成低温热液型金矿床可以划分为高硫型和低硫型两大类,以后一种为主。金矿的形成和分布受破火山口、隐爆角砾岩筒、与火山机构有关的断裂以及区域断裂控制。与金矿有关的火山岩,主要是一套以玄武岩_安山岩_英安岩_流纹岩及其火山碎屑岩组合为特征的钙碱性陆相火山岩,少数为海相_陆相火山岩。矿体赋存在火山岩、潜火山岩中,少数在斑岩中。主要的蚀变组合为冰长石_石英(玉髓)_绢云母或明矾石_高岭石_石英(玉髓)。金矿成矿时代在340~244 Ma之间,金矿在时间和空间上与新疆古生代在(350±10) Ma、(300±10) Ma和(250±10) Ma 3个阶段的大规模火山_潜火山活动有密切关系。金矿床形成的地球动力学背景为区域伸展环境或大范围挤压背景下的局部伸展环境。
Abstract:The basic characteristics of the epithermal gold deposits in northern Xinjiang are described briefly in this paper. The epithermal gold deposits in northern Xinjiang can be divided into high_sulfidation and low_sulfidation types, with the latter being the main type. The distribution and formation of epithermal gold deposits in northern Xinjiang are structurally controlled by calderas, craters, diatremes and related faults. Volcanic rocks related to the gold deposits are mainly a suite of calc_alkaline continental volcanic rocks, which are composed mainly of basalt_andesite_dacite_rhyolite and relevent pyroclastic rocks, together with minor marine and continental volcanic rocks. Gold orebodies are mainly hosted in volcanic rocks and subvolcanic intrusions, with a few occurring in the porphyry. The alteration assemblages are mainly adularia_chalcedony_sericite in low-sulfidation gold deposits, and alunite_kaolinite_quartz (chalcedony) in high_sulfidation gold deposits. The ore_forming ages of the epithermal gold deposits in northern Xinjiang are in the range of 340~244 Ma, corresponding to the large_scale volcanic_subvolcanic activities at (350±10) Ma, (300±10) Ma and (250±10) Ma. It is held that all the epithermal gold deposits in northern Xinjiang are products of magmatic heat events in the extensional tectonic setting or the local extensional environment under the large_scale compressional background.
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基金项目:国土资源大调查项目(200413000026)、国家重点基础研究发展规划项目(2001CB409807)和国家重点基础研究发展规划项目(G1999043211)
引用文本:
杨富全,毛景文,夏浩东,赵财胜,李蒙文,叶会寿.2005.新疆北部古生代浅成低温热液型金矿特征及其地球动力学背景[J].矿床地质,24(3):242~263.2005.Geological characteristics and tectonic settings of Paleozoic epithermal gold deposits in northern Xinjiang[J].Mineral Deposits24(3):242~263
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