熊耳山—外方山矿集区金—钼成矿系统

发布时间：2018-01-03 04:18

  本文关键词：熊耳山—外方山矿集区金—钼成矿系统　出处：《中国地质大学(北京)》2017年博士论文　论文类型：学位论文

  更多相关文章： Au-Mo矿床 叠加成矿作用 成矿系统 熊耳山-外方山

【摘要】：熊耳山-外方山矿集区是我国重要的金-钼等资源产地。前人对熊耳山-外方山矿集区各时期金-钼矿床进行了较多研究,然而对叠加成矿研究尚少。本文通过岩石地球化学、稳定同位素、流体包裹体、非传统Fe同位素等分析,解析复合造山过程和叠加成矿作用,尝试建立成矿系统,获得如下主要成果。通过LA-ICP-MS锆石U-Pb分析,厘定熊耳群火山岩喷发时限为1828~1746Ma,岩石地球化学数据分析认为熊耳群形成于裂谷环境;限定秦岭造山带东秦岭部分同碰撞和后碰撞转换时间为227 Ma,秦岭造山带同碰撞局部拉张环境以及后碰撞张性环境各发育一期岩浆活动;五丈山和白土塬岩体分别侵位于160Ma、165 Ma,形成于陆缘弧环境;太山庙复式岩体三期侵入时间分别为125Ma、121Ma、115 Ma形成于华北克拉通大规模减薄环境。划分出6个成矿期,1875~1855 Ma俯冲环境斑岩型钼矿床,1831~1680 Ma裂谷环境斑岩型钼矿床,250~227 Ma同碰撞环境造山型钼矿床,227~194 Ma后碰撞环境造山型和碳酸盐型钼矿床,163~135 Ma俯冲环境斑岩型钼矿床,135~116Ma岩石圈减薄环境造山型金矿床、岩浆热液型金矿床和斑岩型钼矿床。解析了典型矿床如造山型金矿床、造山型钼矿床、岩浆热液型金矿床等矿床类型及叠加成矿作用,其中槐树坪金(钼)矿床为三叠纪造山型钼矿床和白垩纪造山型金矿床叠加成矿,祁雨沟金矿床为早白垩世早期斑岩型钼矿床和早白垩世晚期岩浆热液型金矿床叠加成矿。建立了熊耳山-外方山矿集区金-钼成矿系统,其重要矿床形成机制如下:造山型钼矿床形成于华北、扬子板块同碰撞与后碰撞环境,分别为俯冲板片变质脱水并混合岩浆热液携带壳幔混源钼成矿,以及变质流体萃取地壳中钼成矿;碳酸岩型钼矿床形成于华北、扬子板块后碰撞环境,岩浆热液携带幔源钼成矿;造山型、岩浆热液型金矿床形成于岩石圈减薄环境,分别为变质热液混合少量岩浆热液萃取壳源金成矿,以及岩浆热液携带幔源金成矿;斑岩型钼矿床形成于洋陆俯冲、陆内裂谷和陆壳减薄环境,为岩浆热液携带壳幔混源钼成矿。
[Abstract]:Xiong 'ershan-Waifangshan ore accumulation area is an important source of gold-molybdenum resources in China. Many researches have been carried out on the gold-molybdenum deposits in Xiong 'ershan-Waifangshan ore accumulation area in various periods. However, there are few studies on superimposed metallogeny. Through the analysis of rock geochemistry, stable isotopes, fluid inclusions and unconventional Fe isotopes, the complex orogenic process and superimposed mineralization are analyzed in this paper. Based on LA-ICP-MS zircon U-Pb analysis, the eruption time of volcanic rocks in Xiong'er Group is determined to be 1828 ~ 1746 Ma. According to the petrogeochemical data, the Xiong'er group was formed in the rifting environment. The partial and post-collision transition time of East Qinling orogenic belt is 227 Ma.The local extensional environment and post-collisional tensional environment of Qinling orogenic belt developed magmatic activity in each phase. The Wuzhangshan and Baituyuan intrusions were located at 160 Mai 165 Ma, respectively, and formed in the continental margin arc environment. The third stage intrusion time of the Taishanmiao complex is 125 Ma / 121 Ma ~ (115 Ma) formed in a large scale thinning environment of the North China Craton, and 6 metallogenic periods have been divided. The porphyry molybdenum deposit in 1875 and 1855 Ma subducted environment is of the same collision environment as the porphyry molybdenum deposit of 1831 ~ 1680 Ma rift. The post-collisional orogenic and carbonate molybdenum deposits of 2270.194 Ma subducted porphyry molybdenum deposits at 135Ma. A series of gold deposits, magmatic hydrothermal gold deposits and porphyry molybdenum deposits have been developed. Typical deposits, such as orogenic gold deposits and orogenic molybdenum deposits, have been analyzed in 135U 116Ma lithospheric thinning environment type gold deposit, magmatic hydrothermal type gold deposit and porphyry type molybdenum deposit. The magmatic hydrothermal type gold deposit and its superposition mineralization, among which the Huaishuping gold (molybdenum) deposit is a Triassic orogenic type molybdenum deposit and Cretaceous orogenic type gold deposit superimposed metallogenic. The Qiyugou gold deposit is a porphyry type molybdenum deposit in early Cretaceous and magmatic hydrothermal type gold deposit in late early Cretaceous. The gold-molybdenum metallogenic system in Xiongershan-Waifangshan ore concentration area has been established. Its important deposit formation mechanism is as follows: the orogenic molybdenum deposit was formed in North China, the Yangtze plate collision and post-collision environment, respectively, subduction plate metamorphic dehydration and mixed magmatic hydrothermal fluid carrying crust and mantle mixed molybdenum mineralization. And metamorphic fluid extraction of molybdenum mineralization in the crust; The carbonatite molybdenum deposit was formed in North China, in the post-collision environment of the Yangtze plate, and the magmatic hydrothermal solution carried the mantle source molybdenum mineralization. The orogenic and magmatic hydrothermal gold deposits are formed in the lithospheric thinning environment. They are metamorphic hydrothermal fluids mixed with a small amount of magmatic hydrothermal extraction crust-derived gold deposits and magmatic hydrothermal fluids carrying mantle-derived gold mineralization. Porphyry molybdenum deposits were formed in the subduction of oceanic land, intracontinental rift and continental crust thinning environment, and were formed by magmatic hydrothermal fluids carrying crust-mantle mixed molybdenum mineralization.
【学位授予单位】：中国地质大学(北京)
【学位级别】：博士
【学位授予年份】：2017
【分类号】：P618.51;P618.65
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本文编号：1372340