Analysis of closed and open numerical systems of geochemical data in spatial statistics environment in order to separate anomalous areas

  • 0Department of Mining Engineering, Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran. M.seyedrahimi@uma.ac.ir.

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Summary

This summary is machine-generated.

This study introduces U-modeling of log-transformed geochemical data for anomaly separation. The Additive Log-Ratio (ALR) transformation with U-modeling shows superior alignment with field data for mineral exploration.

Area Of Science

  • Geochemistry
  • Spatial Statistics
  • Mineral Exploration

Background

  • Geochemical data often exhibit non-normality and outliers, necessitating closed numerical systems.
  • Standard statistical methods face challenges analyzing such complex geochemical datasets.
  • Log-transformed data and novel modeling approaches are crucial for accurate geochemical anomaly detection.

Purpose Of The Study

  • To introduce and evaluate U-modeling of log-transformed geochemical data for anomaly separation.
  • To compare the effectiveness of Additive Log-Ratio (ALR) and Centered Log-Ratio (CLR) transformations in conjunction with U-modeling.
  • To assess the spatial distribution of copper-gold and molybdenum mineralization in the Doostbiglou region, Iran.

Main Methods

  • Application of Additive and Centered Logarithmic Transformations (ALR and CLR) to geochemical data.
  • Modeling of transformed data using the U-spatial statistics algorithm for anomaly detection.
  • Generation and validation of anomaly maps against field exploration data.

Main Results

  • Both ALR and CLR transformations, when U-modeled, effectively separated anomalous areas and agreed with field data.
  • U-modeling of ALR-transformed data demonstrated a closer alignment with field observations.
  • The U-modeling approach provided a more precise representation of mineralization trends in the study area.

Conclusions

  • U-modeling of log-transformed geochemical data is a promising technique for anomaly separation.
  • The ALR transformation combined with U-modeling is recommended for spatial element distribution analysis and threshold determination.
  • This novel approach enhances the accuracy of mineral exploration by better delineating anomalous zones.

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