| Titre | Multifractal modeling of worldwide and Canadian metal size-frequency distributions |
| Auteur | Agterberg, F |
| Source | Natural Resources Research 2019 p. 1-12, https://doi.org/10.1007/s11053-019-09460-1 |
| Année | 2019 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20180412 |
| Éditeur | Springer Nature |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1007/s11053-019-09460-1 |
| Media | papier; en ligne; numérique |
| Formats | pdf (Adobe® Reader®); html |
| Sujets | établissement de modèles; potentiel minier; estimation des ressources; gisements minéraux; métaux; métaux de base; métaux précieux; cuivre; zinc; or; argent; méthodes statistiques; analyses statistiques;
distributions de fréquences; analyses d'ensemble; distribution minérale; géologie économique; géomathématique |
| Illustrations | tables; plots; frequency distribution diagrams |
| Diffusé | 2019 02 02 |
| Résumé | (disponible en anglais seulement)
The Pareto-lognormal frequency distribution, which can result from multifractal cascade modeling, previously was shown to be useful to describe the worldwide
size-frequency distributions of metals including copper, zinc, gold and silver in ore deposits. In this paper, it is shown that the model also can be used for the size-frequency distributions of these metals in Canada which covers 6.6% of the
continental crust. Like their worldwide equivalents, these Canadian deposits show two significant departures from the Pareto-lognormal model: (1) there are too many small deposits, and (2) there are too few deposits in the transition zone between the
central lognormal and the upper tail Pareto describing the size-frequency distribution of the largest deposits. Probable causes of these departures are: (1) historically, relatively many small ore deposits were mined before bulk mining methods became
available in the twentieth century, and (2) economically, giant and supergiant deposits are preferred for mining and these have strongest geophysical and geochemical anomalies. It is shown that there probably exist many large deposits that have not
been discovered or mined. Although overall the samples of the size-frequency distributions are very large, frequencies uncertainties associated with the largest deposits are relatively small and it remains difficult to estimate more precisely how
many undiscovered mineral deposits there are in the upper tails of the size-frequency distributions of the metals considered. |
| GEOSCAN ID | 313705 |
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