相山铀矿田西部深钻岩心成像光谱编录及蚀变分带特征  

Deep drill logging and its alteration zoning features based on hyperspectral core imaging in west of Xiangshan uranium orefield

作　　者：张川[1,2] 叶发旺[1] 徐清俊 邱骏挺[1] ZHANG Chuan;YE Fawang;XU Qingjun;QIU Junting(National Key Laboratory of Remote Sensing Information and Imagery Analyzing Technology,Beijing Research Institute of Uranium Geology,Beijing 100029,China;Faculty of Geosciences and Resources,China University of Geosciences (Beijing),Beijing 100083,China)

机构地区：[1]核工业北京地质研究院遥感信息与图像分析技术国家级重点实验室,北京100029 [2]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《国土资源遥感》2019年第2期231-239,共9页Remote Sensing for Land & Resources

基　　金：中核集团重点专项“龙灿”创新示范工程项目“相山基础地质研究”(编号:LCD116);中核集团龙腾二期项目“铀及多金属矿产勘查高光谱遥感综合应用示范”(编号:遥LTY1604)共同资助

摘　　要：相山盆地西部是目前相山铀矿田攻深找盲的重要潜力区域,其深部具体的蚀变分带仍有待进一步的研究。成像光谱岩心扫描技术为揭示深部蚀变信息提供了一种新的手段。通过对相山西部牛头山地区的科学深钻进行岩心成像光谱扫描和数据处理,完成了5类蚀变矿物的岩心填图,采用像元分类统计算法获得了整个钻孔的蚀变矿物相对含量编录曲线。通过与地质岩性编录和物探测井曲线的对比,印证了岩心成像光谱编录蚀变信息的可靠性。根据深钻岩心成像光谱编录结果,基底以上可划分为3个蚀变带:上--绿泥石化为主,中--高岭石+地开石化和伊利石(主要是短波伊利石)化为主,下--伊利石(长波伊利石多、短波伊利石少)化为主。钻孔上、下2段铀矿化具有明显不同的蚀变矿物组合特征,反映不同波长伊利石的形成环境具有相对差异性。短波伊利石形成于相对偏酸性的流体环境,与酸性蚀变主导的铀成矿密切相关,长波伊利石形成于相对偏碱性的流体环境,与铀成矿的相关性不高。深钻蚀变分带特征反映了偏酸性的流体活动晚于偏碱性的流体活动,并作用于后者之上,铀伴随着后期的钾交代和偏酸性的流体活动逐渐富集;深部碱交代作用的演化具有钠交代→钾交代→酸交代的总体演化规律。The west of Xiangshan basin is an important potential area in the search for deep-buried uranium ore deposits in Xiangshan uranium orefield,and its deep alteration zoning remains to be further explored.Imaging hyperspectral core scanning technique provides a new means for revealing deep alteration information.On the basis of the imaging hyperspectral scanning data oFdeep drilling cores in the Niutoushan area of western Xiangshan,mapping of 5 types of altered minerals was realized by data processing.Then,pixels statistic algorithm was used to obtain the relative content logging curve of each altered mineral.The reliability of the imaging hyperspectral logging was verified by comparing the geological lithology and geophysical logging curves.According to the results of imaging hyperspectral logging oFdeep drill holes,the formations overlying the basement can be divided into three alteration zones.The main alteration of the first is chloritization,which is located in the upper part,and the second main alterations located in the middle part contain kaolinization,dickitization,and illitization dominated by shortwave illite,and the third main alteration is illitization that is characterized by more long wave and less short wave illite,located in the lower part.Uranium mineralizations in the upper and lower parts of the borehole have distinct features of altered mineral combinations and show that formation environments of illites with different wavelength characteristics are relatively different.The short wave illite tends to form in relatively acidic fluid environment,closely related to uranium mineralization controlled by acid alterations;the long wave illite tends to form in relatively alkaline fluid environment and is not closely related to uranium mineralization.Alteration zoning features oFdeep drill holes reveal that acidic fluid activity is later than alkaline fluid activity and acts on the latter.Uranium is gradually enriched with deuteric potassium metasomatism and acidic fluid activity.The action oFdeep fluid

关 键 词：相山 深钻 岩心 成像光谱 蚀变矿物 铀矿化 

分 类 号：TP79[自动化与计算机技术—检测技术与自动化装置] P627[自动化与计算机技术—控制科学与工程]