Application of 2D-EMD/PCA in gold and key metals prospecting in Jiaodong
With the continuous rise in global demand for mineral resources in recent years from manufacturing industry and global economy,it is an urgent need to develop new methods for proven and hidden mineral resources.However,multistage mineralization results in complex,overlapping distribution of ore-forming elements in geological units,and most minerals are often associated with multiple elements.To address this problem we used a combination of two-dimensional empirical mode decomposition(2D-EMD)and principal component analysis(PCA)to extract local and regional multielement anomaly components from the drainage sediment geochemical data in the Jiaodong gold polymetallic ore field.The prospective areas were identified from complex,overlapping anomalies,and the multielement mineral resource potential of the study area was evaluated by geochemical block method.The results provide a scientific basis for the exploration and evaluation of symbiotic minerals.Specifically,(1)Au-Ag-Cd and Be-La-Mo-Nb-Th-U-Y multielement combinations were established by PCA;(2)the local and regional anomaly components of the multielement combinations were identified by 2D-EMD based on their principal component scores;(3)the prospective area of the two multielement combinations could be delineated using local anomaly components,and the high background belt could be identified by regional anomaly components.Combined with the local anomaly components and the spatial distribution of granite,we infer that Au-Ag-Cd mineralization is related to the Linglong granite and Guojialing granodiorite intrusions,and Be-La-Mo-Nb-Th-U-Y mineralization is related to the Guojialing granodiorite and Weideshan monzonite intrusions.The Guojialing granodiorite rock mass may have dual metallogenetic characteristics of both precious and critical metals.
2D-EMDPCAmultielement combination anomaly componentJiaodong gold polymetallic ore field
万方数据
维普
