Quality and quantity assessment using multivariate compositional and univariate analysis in the Glojeh polymetallic vein mineralization

Background separation from anomalous concentration is a fundamental process in exploration geochemistry for polymetallic ore deposits. Therefore, fractal modeling and multivariate analysis have been applied to vein identification in the Glojeh polymetallic deposit, Tarom zone, northwestern Iran. The C-N fractal modeling demonstrated that the threshold value is equal to 103.34 ≈ 2000 ppb, and the total number of 100.89 ≈ 8 samples are anomalous for Au. Anomalous and background populations may do not represent major differences using the frequency distribution, but they possibly could be different in spatial patterns. Therefore, the application of single element fractal modeling would not be able to determine polymetallic veins and veinlet samples. Accordingly, a better anomaly identification may be approached using the multivariate analysis and compositional isometric log-ratio (Ilr) transformed data. It revealed that sample ID’s of 33, 29, 30, 28, 32, 35, 47, 81, 80, 31, 34 and 36 are concentrated from (Ag, Pb, As, Au) > (Te, Mo) > (Zn, S) > (W, Cu) > (Be and Cd). The factor analysis based on Ilr-transformed data indicated Au, As, Mo, W, Ag, Pb, Te, Be, and Zn are enriched and can be considered as pathfinder elements for tracing a polymetallic mineralization, while Al, K, Ba, Ce, La, Na, Zr, Rb, Y and Th have been depleted. These findings will complement and improve the results of fractal modeling to the determination of several ore-related elements, and they were quantitatively and qualitatively assessed. Finally, the mineralization type could be classified in a high sulfidation epithermal deposit.