Natural Resources Research

, Volume 15, Issue 1, pp 49–65 | Cite as

Mineral-Potential Mapping: A Comparison of Weights-of-Evidence and Fuzzy Methods

  • Telmo F. P. de Quadros
  • Jair C. Koppe
  • Adelir J. Strieder
  • João F. C. L. Costa

Guidelines for mineral exploration normally are based on models for a given type of ore deposit. These guidelines usually are based on descriptive and metallogenetic data, and on expertise judgment. This paper presents a comparison between results produced by two of these methods: weights-of-evidence and fuzzy logic. The mineral favorability maps for gold exploration were produced in a Geographic Information Systems (GIS) environment and took into account five sources of data and information: (i) satellite images; (ii) a geochemical survey; (iii) an airborne geophysical survey; (iv) geo-structural mapping; and (v) ground elevation. These data and information were integrated through a conceptual model developed for gold mines and occurrences in the studied region. Both favorability maps highlighted the known gold occurrences and validated the approach. High gold potential areas highlighted by both maps show good correlation. But, the weights-of-evidence method delineated smaller highly favorable areas compared to the fuzzy logic map. On the other hand, the weights-of-evidence method produced higher biased probability within the favorable zones when compared with fuzzy logic methods favorable areas. New exploration targets were identified and should be further investigated.


Geo-mathematics fuzzy logic weights-of-evidence GIS mineral exploration ore deposit modeling. 



The authors would like to thank CAPES, CNPq, and the staff of the Crystallex Inc. to support this research.


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Copyright information

© International Association for Mathematical Geology 2006

Authors and Affiliations

  • Telmo F. P. de Quadros
    • 1
  • Jair C. Koppe
    • 2
  • Adelir J. Strieder
    • 2
  • João F. C. L. Costa
    • 2
  1. 1.FEPAM–Fundação Estadual de Proteção Ambiental do Estado do Rio Grande do SulRua Carlos ChagasPorto AlegreBrasil
  2. 2.Mining Engineering DepartmentFederal University of Rio Grande do SulPorto AlegreBrasil

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