Analysis of geochemical patterns in a soil profile over mineralized bedrock

Jie Yang*, Zhaoxian Yuan, Eric Grunsky, Qiuming Cheng, Shubin Zhou

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)

Abstract

Transported soils cause difficulties in the identification of geochemical anomalies. It has been demonstrated that the joint application of local singularity analysis (LSA) and principal component analysis (PCA) can identify geochemical anomalies effectively, especially in regolith-covered areas. However, more convincing evidence is needed to explain the reasons for this. In this study, a soil profile overlying several mineralized veins cutting through bedrock was analysed in situ using a portable X-ray fluorescence spectrometer. The patterns of two mineralization-related elements, Cu and Mo, were analysed. The results revealed that the element concentrations of the soil sharply decreased as the distance from the bedrock increased, and this relationship can be described by a power-law model. LSA enhanced several vein-like anomalies corresponding to the mineralization veins in the bedrock, and the presence of vertically elongated weak anomalies in the soil indicates the migration of ore elements originating from the underlying bedrock through the soil. The statistics show that the patterns of the local singularity index (LSI) are stable at different depths and in different media, whereas the concentration patterns are not. In addition, the mineralization-related elements have a higher correlation coefficient for the LSI than for the concentration. Since a previous simulation study determined that a mineralization-indicative first principal component prefers that the variables have a close relationship and that the variables have similar patterns in different geological objects, the patterns discovered in this study explain why LSA is effective in identifying geochemical anomalies, especially when combined with PCA.

Original languageEnglish
Article numbergeochem2021-088
Pages (from-to)1-8
Number of pages8
JournalGeochemistry: Exploration, Environment, Analysis
Volume22
Issue number3
Early online date9 May 2022
DOIs
Publication statusPublished - 31 Aug 2022

Keywords

  • data mining
  • local singularity analysis
  • portable X-ray fluorescence spectrometer
  • principal component analysis
  • regolith-dominated area
  • soil profile

Fingerprint

Dive into the research topics of 'Analysis of geochemical patterns in a soil profile over mineralized bedrock'. Together they form a unique fingerprint.

Cite this