| The main objective of this work is to investigate whether approaches based on fuzzy logic can be incorporated into those steps of the resource evaluation process where high uncertainty prevails.; In the present work, the fuzzy query concept has been used to define fuzzy cutoffs for mineral grade, and this approach has been applied to the block models of two small mineralized zones in the Worthington offset, owned by Inco Ltd. The sharp cutoff number (e.g. Ni > 0.5% and/or value > {dollar}30 per ton) is replaced with a set of numbers and a membership function to determine the membership value for every member of the set. A union of these sets was then used to define "recoverable resource", which showed detailed characteristics of the blocks close to the cutoff grade. This approach also showed how any change, addition or deletion of any related parameter would affect the resource definition.; One potential application of fuzzy logic is to use fuzzy controllers for grade estimation. This approach may provide a useful alternative to kriging, which is currently the most widely used estimation technique, especially in the case of limited data availability. (Abstract shortened by UMI.)... |
