1.The Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China; 2.Institute of Geological Survey, China University of Geosciences, Wuhan 430074,China; 3.State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China
Abstract:In order to weaken the closure effect of the geochemical data which serve as typical component data, the authors analyzed the spatial distribution of geochemical elements in the Laji Mountains. The authors used the isometric log-ratio(ilr) transformation to "open" the geochemical data of the water sediments, built the combined model using robust principal component analysis (RPCA) to identify the combined geochemical anomalies and employed fractal filtering technique to strengthen weak anomalies and separate anomaly from background. In this way, the authors delineated geochemical anomaly so as to guide mineral exploration better. The result obtained by using RPCA displays two different compositional assemblages: (I) Au-As, probably representing tectonic-altered rock type gold deposit like the east ditch of Jinyuan, and (II) Cu-Ni, likely representing copper-nickel sulfide mineralization such as Lashuixia. The results from S-A filter technique can decompose anomalies further, strengthen weak anomaly and reduce the abnormal area in the strong background and, in combination with the geological survey of the study area and the anomaly map, can better search for tectonic-altered rock type Au-As deposits and Cu-Ni sulfide mineralization.
姜晓佳, 陈鑫, 郑有业, 高顺宝, 欧阳嵩, 张永超, 郑磊, 黄建. 拉脊山东段地区Au、Cu地球化学组合异常识别与提取[J]. 物探与化探, 2017, 41(3): 459-467.
JIANG Xiao-Jia, CHEN Xin, ZHENG You-Ye, GAO Shun-Bao, OUYANG-Song, ZHANG Yong-Chao, ZHENG Lei, HUANG Jian. The recognition and extraction of Au, Cu geochemical composite anomalies:A case study of the east of Laji Mountains. Geophysical and Geochemical Exploration, 2017, 41(3): 459-467.
[1] 王学求. 矿产勘查地球化学:过去的成就与未来的挑战[J]. 地学前缘,2003, 10(1): 239-248. [2] 王瑞廷,毛景文,任小华,等. 区域地球化学异常评价的现状及其存在的问题[J]. 中国地质,2005, 32(1): 168-175. [3] 谢学锦,任天祥,奚小环,等. 中国区域化探全国扫面计划卅年[J]. 地球学报,2009, 30(6): 700-716. [4] 王学求,谢学锦,张本仁,等. 地壳全元素探测技术与实验示范[J].地球学报, 2011,32(s1):65-83. [5] Chayes F, Trochimczyk J. An effect of closure on the structure of principal components[J]. Journal of the International Association for Mathematical Geology,1978, 10(4): 323-333. [6] Aitchison J.The statistical analysis of compositional data[J].Journal of the Royal Statistical Society, 1986, 44(2):139-177. [7] Gregory F P.The statistical analysis of compositional data[J].Technometrics, 1988, 30(1):120-121. [8] 周蒂. 地质成分数据统计分析——困难和探索[J]. 地球科学,1998,23(2): 147-152. [9] Carranza E J M. Analysis and mapping of geochemical anomalies using logratio-transformed stream sediment data with censored values[J]. Journal of Geochemical Exploration,2011, 110(2): 167-185. [10] Zuo R G. Identification of geochemical anomalies associated with mineralization in the Fanshan district, Fujian, China[J]. Journal of Geochemical Exploration,2014, 139: 170-176. [11] Filzmoser P, Hron K, Reimann C. Principal component analysis for compositional data with outliers[J]. Environmetrics,2009, 20(6): 621-632. [12] Nazarpour A, Omran N R, Paydar G R, et al. Application of classical statistics, logratio transformation and multifractal approaches to delineate geochemical anomalies in the Zarshuran gold district, NW Iran[J]. Chemie der Erde:Geochemistry,2015, 75(1): 117-132. [13] Wang H C, Cheng Q M, Zuo R G. Spatial characteristics of geochemical patterns related to Fe mineralization in the southwestern Fujian province (China)[J]. Journal of Geochemical Exploration,2015, 148: 259-269. [14] Zuo R G, Wang J, Chen G X,et al. Identification of weak anomalies: A multifractal perspective[J]. Journal of Geochemical Exploration, 2015,148: 12-24. [15] Cheng Q M. Non-linear theory and power-law models for?Information integration and mineral resources quantitative assessments[J]. Mathematical Geosciences, 2008,40(5): 503-532. [16] Cheng Q M, Agterberg F P,Ballantyne S B. The separation of geochemical anomalies from background by fractal methods[J]. Journal of Geochemical Exploration, 1994,51(2): 109-130. [17] 青海省地质矿产局. 青海省区域地质志[M]. 北京: 地质出版社, 1991:1-752. [18] 青海省地质矿产局. 青海省岩石地层[M]. 武汉: 中国地质大学出版社, 1997:340. [19] 汤中立,闫海卿,焦建刚,等. 中国岩浆硫化物矿床新分类与小岩体成矿作用[J]. 矿床地质,2006, 25(1): 1-9. [20] 张照伟,李文渊,高永宝,等. 青海化隆基性-超基性岩带铜镍矿成矿条件与找矿潜力[J]. 西北地质,2012,45(1): 140-148. [21] 杨巍然,邓清禄,吴秀玲. 拉脊山造山带断裂作用特征及与火山岩、蛇绿岩套的关系[J]. 地质科技情报,2000, 19(2): 5-11. [22] 殷鸿福,张克信. 中央造山带的演化及其特点[J]. 地球科学:中国地质大学学报,1998,23(5): 438-442. [23] Sun X, Zheng Y Y, Wang C M, et al. Identifying geochemical anomalies associated with Sb-Au-Pb-Zn-Ag mineralization in North Himalaya, southern Tibet[J]. Ore Geology Reviews,2016, 73: 1-12. [24] Zhang Z, Zuo R, Cheng Q. Geological features and formation processes of the makeng Fe deposit, China[J]. Resource Geology,2015, 65(3): 266-284. [25] 周洪伟. 正态性检验的几种常用的方法[J]. 南京晓庄学院学报,2012(3): 13-18. [26] 何凤萍,王正海,方臣,等. 庞西垌地区Ag-Au矿化信息识别与提取[J]. 地质科技情报,2014,33(2): 110-115. [27] Zhao J, Wang W L, Dong L H, et al. Application of geochemical anomaly identification methods in mapping of intermediate and felsic igneous rocks in eastern Tianshan, China[J]. Journal of Geochemical Exploration,2012, 122: 81-89. [28] Egozcue J J, Pawlowsky-Glahn V, Mateu-Figueras G, et al. Isometric logratio transformations for compositional data analysis[J]. Mathematical Geology,2003, 35(3): 279-300. [29] Filzmoser P, Hron K. Correlation analysis for compositional data[J]. Mathematical Geosciences,2009, 41(8): 905-919. [30] Aitchison L. The statistical analysis of compositional data[J]. Journal of the Royal Statistical Society: Series B,1982, 44(24): 139-177. [31] Fritsch V, Varoquaux G, Thyreau B, et al. Detecting outliers in high-dimensional neuroimaging datasets with robust covariance estimators.[J]. Medical Image Analysis,2012, 16(7): 1359-1370. [32] 张蓓,王顺芳. 基于MCD稳健估计的PCA人脸识别算法[J]. 计算机工程与设计,2015,36(3): 778-782. [33] Cheng Q M, Xu Y G, Grunsky E. Integrated spatial and spectrum method for geochemical anomaly separation[J]. Natural Resources Research,2000, 9(1): 43-52. [34] Cheng Q M. Spatial and scaling modelling for geochemical anomaly separation[J]. Journal of Geochemical Exploration,1999, 65(3): 175-194. [35] Cheng Q M. A new model for quantifying anisotropic scale Invariance and for decomposition of mixing patterns[J]. Mathematical Geology,2004, 36(3): 345-360. [36] 成秋明,张生元,左仁广,等. 多重分形滤波方法和地球化学信息提取技术研究与进展[J]. 地学前缘,2009,16(2): 185-198. [37] Zuo R G, Xia Q L, Wang H C. Compositional data analysis in the study of integrated geochemical anomalies associated with mineralization[J]. Applied Geochemistry,2013, 28: 202-211. [38] Afzal P, Alghalandis Y F, Khakzad A, et al. Delineation of mineralization zones in porphyry Cu deposits by fractal concentration-volume modeling[J]. Journal of Geochemical Exploration,2011, 108(3): 220-232. [39] 朱有光, 蒋敬业, 李泽九, 等. 试论我国重要景观区中景观*表生因素对金*铜区域地球化学异常标志的影响[J]. 物探与化探, 2001,25(6):418-424. [40] 赵娟, 孙泽坤, 李明喜. 青海景观区特征和地球化学勘查方法技术[J]. 物探与化探, 2004,28(3):239-241.