湘东北幕阜山地区中生代构造—岩浆特征及其对稀有金属伟晶岩的控制  被引量:8

Mesozoic tectono—magmatic characteristics and their control on rare metal pegmatites in Mufushan area,northeastern Hunan

在线阅读下载全文

作  者:柏道远 文春华 黄建中 李彬 周芳春 张立平 陈虎 陈剑锋 陈旭 BAI Daoyuan;WEN Chunhua;HUANG Jianzhong;LI Bin;ZHOU Fangchun;ZHANG Liping;CHEN Hu;CHEN Jianfeng;CHEN Xu(Hunan Institute of Geology Survey,Changsha,410016;State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang,330013;Hunan Institute of Geological Disaster Investigation and Monitoring,Changsha,410100)

机构地区:[1]湖南省地质调查所,长沙410016 [2]东华理工大学核资源与环境国家重点实验室,南昌330013 [3]湖南省地质灾害调查监测所,长沙410100

出  处:《地质论评》2023年第3期855-880,共26页Geological Review

基  金:湖南省科技厅重点研发项目(编号:2019SK2261);有色金属成矿预测与地质环境监测教育部重点实验室开放基金资助项目(编号:2021YSJS04);湖南省地质院科研项目(编号:HNGSTP202105、201917)的成果。

摘  要:幕阜山地区发育燕山期大型花岗岩体,形成了大量花岗伟晶岩脉及相关稀有金属矿床或矿化体。尽管前人对该地区花岗岩、伟晶岩和稀有金属矿床的地质地球化学特征、形成时代、空间展布和演化过程等进行了系统研究并取得大量成果,但地质构造对花岗岩和稀有金属伟晶岩的控制作用尚缺乏研究。鉴此,笔者等通过跨幕阜山岩体接触带的多个地质剖面调查,结合区域地质和矿产发育特征,对幕阜山地区中生代构造—岩浆演化过程以及构造对花岗岩体、伟晶岩脉和接触变质带的控制作用等进行了研究,形成以下主要认识:①中生代—新生代早期,研究区自早至晚经历了早—中三叠世海相盆地、中三叠世后期—晚三叠世印支运动、晚三叠世晚期—中侏罗世早期类前陆盆地、中侏罗世晚期早燕山运动、晚侏罗世—早白垩世早期花岗质岩浆活动与成矿、早白垩世晚期—古近纪中期区域伸展与断陷盆地、古近纪中晚期NE向挤压等7个构造阶段。②幕阜山岩体边界主要受NW向、NE向和NEE向等3组断裂控制,其构造机制实质为岩体区断块和岩体外断块对岩浆侵位过程的控制。③岩体侵位构造可定性划分为低侵位缓倾接触构造、低侵位陡倾接触构造、高侵位缓倾接触构造和高侵位陡倾接触构造等4类,其中低侵位缓倾接触构造对花岗伟晶岩的形成最为有利。④控制伟晶岩脉(体)的构造包括层面或层间剪切面、逆断裂、岩体接触带等主导性控岩构造,以及走滑剪切破裂、膝折面等限制性控岩构造。层间剪切面主要形成于武陵运动,EW向和NWW向逆断裂、NWW向膝折面、NNE向左行剪切破裂、NNW向右行剪切破裂等形成于印支运动SN向挤压,NWW向右行剪切破裂形成于早燕山运动NWW向挤压;仁里地区构造的走向为叠加后期顺时针旋转后的结果。⑤受岩体接触带和不同类型与规模的面状Objectives:Yanshanian large granite is developed in Mufushan(Mufu Mountains)area,with a large number of granitic pegmatite veins and related rare metal deposits or mineralized bodies formed.Although the predecessors have systematically studied the geological and geochemical characteristics,formation ages,spatial distributions and evolution processes of granite,pegmatite and rare metal deposits in this area,and achieved a lot of results,there is still a lack of research on the controlment of geological structures on granite and rare metal pegmatite.Methods:In view of this,through the investigation of several geological sections across the contact zone of Mufushan granite,combined with the characteristics of regional geology and mineral development,this paper studied the Mesozoic tectono—magmatic evolution and the controlment of structures on granite,pegmatite veins and contact metamorphic zones in Mufushan area.Conclusions:The main achievements are as follows:(1)From Mesozoic to early Cenozoic,the study area experienced 7 tectonic stages,from early to late,such as①marine basin of Early—Middle Triassic,②Indosinian movement of late Middle Triassic to Late Triassic,③semi-foreland basin of late Late Triassic—early Middle Jurassic,④Early Yanshanian movement of late Middle Jurassic,⑤granitic magmatism and mineralization of Late Jurassic to early Early Cretaceous,⑥regional extension and faulted basins of late Early Cretaceous to middle Paleogene,and⑦NE compression in the middle—late Paleogene.(2)The boundary of Mufushan granite is mainly controlled by three groups of fault with NW-,NE-and NEEtrending,whose structural mechanism is essentially the controlment of fault blocks in or outside the granite area on the magma emplacement.(3)The granite emplacement structures of the granite can be qualitatively divided into four types:low emplacement—gently dipping contact structure,low emplacement—steep dipping contact structure,high emplacement—gently dipping contact structure and high emplacement—st

关 键 词:幕阜山 中生代 花岗岩 伟晶岩 构造演化 构造控岩特征 

分 类 号:P618.6[天文地球—矿床学] P588.13[天文地球—地质学]

 

参考文献:

正在载入数据...

 

二级参考文献:

正在载入数据...

 

耦合文献:

正在载入数据...

 

引证文献:

正在载入数据...

 

二级引证文献:

正在载入数据...

 

同被引文献:

正在载入数据...

 

相关期刊文献:

正在载入数据...

相关的主题
相关的作者对象
相关的机构对象