摘要
诸广山中部是华南主要产铀地区之一,以鹿井矿田为研究对象,开展构造变形特征和构造控矿规律的研究,旨在揭示矿体产出规律,为找矿预测提供依据。本文基于野外详细观测和显微构造变形分析,揭示NE向断裂是鹿井地区主要控矿和含矿断裂,属浅层次构造变形,具有多期构造-热液活动特征:经历了早期(晚侏罗世—早白垩世)的压性、中期(早白垩世—古近纪)的张-张扭性和晚期(新近纪)的右行压扭性变形过程。铀矿(化)体主要发育在NE向断裂破碎带中,结合铀成矿时代,主成矿期断裂力学性质表现为张性、张扭性,后期NE向断裂右行压扭变形派生出近EW向、NW向和NS(NNE)向的剪裂隙,一方面对先成铀矿体具有改造作用,另一方面富集部分铀矿体。根据构造组合特征及其控矿规律,认为NE向断裂破碎带中,沿走向存在不连续的脉状、透镜状富铀矿体,而在其他方位的断裂带中可能存在部分铀矿体。
The middle Zhuguangshan area is one of the main uranium-producing areas in South China.The characteristics of structural deformations and ore-controlling structural regularity were studied in order to identify the features of uranium deposits and provide scientific guidance for ore-prospecting in blind ore deposits,with Lujing uranium orefield in middle Zhuaguangshan as the study objects.The authors revealed that NE-trending faults are ore-controlling and ore-hosting faults in Lujing area,as shown by field detailed observation and microscopic structure analyses.NE-trending faults have characteristics of multi-stage tectonic and hydrothermal activities belonging to shallow surface tectonic deformation.Geological phenomena show that NE-trending faults had at least three stages of tectonic events:compression deformation at the early stage(Late Jurassic-Early Cretaceous),tensional and torsion at the late stage(Early Cretaceous-Paleogene),and the faults changed into compress-shear faults at the late stage(Neogene).The uranium orebodies were developed in the NE-trending fracture zone,and the mechanical properties of NE-trending faults were tensional and transtensional during the major ore-forming stage.The near EW,NW and NS(NEE)trending faults were induced from the NE-trending main faults in the later right twisting deformation in Neogene period.The earlier uranium orebodies were reformed by the later tectonic deformation.On the other hand,some parts of the uranium orebodies were concentrated in the later faults.According to the characteristics of structure combination and ore-controlling regularity,the authors hold that the blind uranium orebodies which occurred as veins and lenses existent in the NE-trending fracture zone,and the secondary enrichment of uranium may exist in other direction faults.
作者
孙岳
潘家永
肖振华
刘颖
潘春蓉
钟福军
赖静
SUN Yue;PAN Jiayong;Xiao Zhenhua;LIU Ying;PAN Chunrong;ZHONG Fujun;LAI Jing(State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,Jiangxi,China;School of Earth Sciences,East China University of Technology,Nanchang 330013,Jiangxi,China;No.302 Geological Party of Hunan Nuclear Geology,Chenzhou 423003,Hunan,China)
出处
《中国地质》
CAS
CSCD
北大核心
2020年第2期362-374,共13页
Geology in China
基金
国家自然科学基金(41702076、41772066)
国家科技支撑计划项目(2015BAB05B04)
中国地质调查局项目(121201104000150014)
东华理工大学博士启动基金(DHBK2015324)联合资助。
关键词
鹿井铀矿田
构造解析
找矿预测
矿产勘查工程
诸广山中部
Lujing uranium orefield
structural analysis
ore-finding and prediction
mineral exploration engineering
middle Zhuaguangshan area
