Construction, test and application of a geochemical gold metallogene: Case studies in China

Abstract

In order to trace the geological materials basing on the geochemical survey data, a gold metallogene is constructed according to the idea of the geochemical gene. Eleven elements are sequenced in the gold metallogene as Ti, Sb, Th, Bi, Nb, Au, Zr, Ag, La, Pb, and Y. The reference values to normalize the contents of the 11 elements in the spectral line of the gene are also proposed. The gold metallogene of the ideal ore or the ideal gold mineralized sample is 12020202020 while the gene of the ideal background sample is 10202020202. The properties of heredity, inheritance, variability, and similarity of the metallogene are tested on 8 weathering profiles developed over granite, granodiorite, basalt, andesite, schist outside the gold deposit areas and 3 weathering profiles formed on dolomite, schist, and andesite in the gold deposit areas in China. According to the criterion of the 80% value of the similarity between two genes viewed as the similar gene, the gold metallogene exhibits stable heredity, inheritance, and similarity during weathering of many kinds of rocks but may also display variability in some cases. The similarity value of 40% of the gold metallogene relative to the ideal ore can be viewed as the criterion to discriminate samples with or without gold mineralization. Two weathering profiles developed over granite with K-feldspar alteration and phyllite respectively near gold deposit areas and a cross section profile of a gold ore vein in gold deposit area are selected as case studies to apply the gold metallogene. The results indicate that the gold metallogene may be viewed as an integrated index of recognizing the gold mineralization in geochemical exploration.