基于成分数据分析及S—A分形的地电提取法在川西容须卡地区寻找隐伏锂矿预测研究  

Research onhidden lithium deposit exploration and prediction in Rongxuka area of West Sichuan by geoelectric extraction method based on component data analysis and S-A multifractal technique

作　　者：石佳磊 欧阳菲[1,2] 罗先熔[1,2] 文美兰[1,2] 刘攀峰[1,2] 刘永胜 梁鸣 杨青松 蔡宇群 孙瑶 Shi Jialei;OuYang fei;Luo Xianrong;Wen Meilan;Liu Panfeng;Liu Yongsheng;Liang Ming;Yang Qingsong;Cai Yuqun;Sun Yao(Guilin University of Technology,Guilin 541004,Guangxi,China;College of Earth Science,Institute of Concealed Mine Prospecting,Guilin University of Technology,Guilin 541004,Guangxi,China;Gansu Non-ferrous Engineering Exploration&Research Institute,Tianshui 741024,Gansu,China)

机构地区：[1]桂林理工大学,广西桂林541004 [2]桂林理工大学地球科学隐伏矿床研究所,广西桂林541004 [3]甘肃省有色金属地质勘查局天水矿产勘查院,甘肃天水741024

出　　处：《矿产与地质》2023年第6期1271-1283,共13页Mineral Resources and Geology

基　　金：“十三五”国家重点研发计划课题深部铀成矿信息识别技术研究(编号:2017YFC0602604)资助。

摘　　要：川西容须卡地区以高寒地貌景观为主,由于自然条件恶劣给找矿工作带来较大困难。为实现该区的找矿突破,开展地电提取法测量、分析与锂成矿密切相关的Li、Be、Rb、Cs、U、Th等6种元素。其结果表明原始数据存在明显的闭合效应,给地球化学异常圈定带来一定的干扰;同时,研究区地球化学背景存在较大差异,可能会漏掉有意义的弱异常。为进一步确定各元素之间的关系,明确找矿指示意义,采用成分数据分析方法打开数据之间的闭合效应,对原始数据、对数变换、ilr变换等3种不同数据处理结果进行对比,得出3点结论:①经过对数及ilr变换后的数据比原始数据更接近正态分布;②ilr变换明显消除数据的闭合效应,其中Li、Rb、Cs、U、Th等成矿元素组合对第一主因子PC1正载荷存在较大贡献;③通过S—A异常分解,有效消除研究区背景值的差异,强化低背景区的弱异常,为矿区找矿提供新线索。最后,结合研究区地质成矿规律、元素组合及异常空间分布特征,圈定出4个找矿靶区。Rongxuka area in West Sichuan is dominated by alpine landform landscape,which is difficult for the prospecting work due to the bad natural condition.In order to achieve a breakthrough in prospecting in this area,the geoelectric extraction method is carried out and six elements,Li,Be,Rb,Cs,U and Th,which are closely related to lithium mineralization,are analyzed.The result shows that the original data have obvious closure effect,which brings some interference to anomaly delineation.At the same time,the geochemical background of the study area is quite different,which may miss the significant weak anomaly.In order to further determine the relationship between the elements and to clarify the significance of prospecting indication,the composition data analysis method is used to open the closing effect between the data,and the processing results of three different data such as the original data,logarithm transformation and ilr transformation are compared.(1)The data after logarithmic and ILR transformation is closer to a normal distribution than the original data.(2)The ilr transformation obviously eliminates the closure effect of the data,in which the combination of metallogenic elements such as Li,Rb,Cs,U and Th has a great contribution to the positive load of the first main factor PC1.(3)Through the decomposition of S-A anomalies,the difference of background values in the study area is effectively eliminated,and the weak anomalies in the low background area are strengthened,which provides a new clue for prospecting in the mining area.Finally,according to the geological and metallogenic regularity,element combination and anomaly spatial distribution characteristics of the study area,four favorable prospecting target areas are delineated.

关 键 词：锂矿 地电提取法 成分数据分析 S—A分形 找矿预测 川西容须卡 

分 类 号：P618.71[天文地球—矿床学]