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Natural Resources Research

, Volume 26, Issue 2, pp 223–236 | Cite as

Spatial Pair-Copula Modeling of Grade in Ore Bodies: A Case Study

  • G. Nishani Musafer
  • M. Helen Thompson
  • E. Kozan
  • R. C. Wolff
Article

Abstract

A real-world mining application of pair-copulas is presented to model the spatial distribution of metal grade in an ore body. Inaccurate estimation of metal grade in an ore reserve can lead to failure of a mining project. Conventional kriged models are the most commonly used models for estimating grade and other spatial variables. However, kriged models use the variogram or covariance function, which produces a single average value to represent the spatial dependence for a given distance. Kriged models also assume linear spatial dependence. In the application, spatial pair-copulas are used to appropriately model the non-linear spatial dependence present in the data. The spatial pair-copula model is adopted over other copula-based spatial models since it is better able to capture complex spatial dependence structures. The performance of the pair-copula model is shown to be favorable compared to a conventional lognormal kriged model.

Keywords

Geostatistical modeling Pair-copula Kriging Non-linear spatial dependence Mining 

Notes

Acknowledgements

This research was funded by the Australian Government’s Cooperative Research Centre for Optimising Resource Extraction Grant P3C-030. The authors thank the reviewers for their comments and guidance, which greatly improved discussion and practical aspects of the application.

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Copyright information

© International Association for Mathematical Geosciences 2016

Authors and Affiliations

  1. 1.School of Mathematical SciencesQueensland University of Technology (QUT)BrisbaneAustralia
  2. 2.Cooperative Research Centre for Optimising Resource Extraction (CRC ORE)PullenvaleAustralia
  3. 3.W.H. Bryan Mining and Geology Research CentreUniversity of Queensland (UQ)St LuciaAustralia

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