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Assessing the Uncertainty in Lithology, Grades and Recoverable Resources in an Iron Deposit in Southern Cameroon

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Abstract

Geological modeling is an essential step in mineral resource assessment. Geologists typically use deterministic methods to create interpreted models, which ignore the uncertainty in the geological domain layout. This study explores a hierarchical approach for simulating a categorical variable (lithological domain) and a continuous variable (iron grade) in a deposit located in Cameroon, enhancing confidence and accounting for geological uncertainty in resource evaluation. To achieve this, lithological domains are simulated using a non-stationary variant of the plurigaussian model, followed by the simulation of iron grade while accounting for its spatial correlation within and across domains. Cross-validation is used to validate the model, and the simulated block models are processed to assess in-situ and recoverable resources and their uncertainties.

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Acknowledgments

This research was supported by the National Agency for Research and Development of Chile, through Grants ANID PIA AFB220002 and ANID Fondecyt 1210050. The authors are grateful to two anonymous reviewers for their constructive comments.

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Authors and Affiliations

  1. School of Geology and Mining Engineering, University of Ngaoundéré, P.O. Box 454, Ngaoundéré, Cameroon

    Franklin Ekolle Essoh & Arsène Meying

  2. Department of Mining Engineering, Universidad de Chile, 8370448, Santiago, Chile

    Xavier Emery

  3. Advanced Mining Technology Center, Universidad de Chile, 8370448, Santiago, Chile

    Xavier Emery

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  1. Franklin Ekolle Essoh
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Correspondence to Franklin Ekolle Essoh.

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Ekolle Essoh, F., Emery, X. & Meying, A. Assessing the Uncertainty in Lithology, Grades and Recoverable Resources in an Iron Deposit in Southern Cameroon. Nat Resour Res 32, 2515–2540 (2023). https://doi.org/10.1007/s11053-023-10276-3

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