Abstract

Many attempts have been made to classify mineral resources and associate them with the rocks in which they generally occur. The present investigation is based on an empirically discovered association between the variety of mineral resources and the variety of geology (i.e. rock-types) at the surface in regions which are well developed. Using diversity measures there is a linear relationship between the variety of mineral resources and the geological diversity of a region as follows: Y = 11.277 + 1.846X, where Y = (s - 1), the number of resources minus one and X = (s - 1) the number of geological rock-types minus one. The degree of linear association between the variables is r² = 80 per cent.

This relationship may be used as a predictive model by quantifying the geological variety at the surface and predicting the expected variety of resources. Both positive and negative deviations from the expected values given by the model are interpretable; when the resource variety is below its expected value (as for example in Alaska and Minnesota) the region is evidently underdeveloped in terms of the variety of resources in production. On the other hand, when the resource diversity is higher than that expected for the region on the basis of its geological diversity (as for example, Colorado, New Mexico, and Texas) it suggests either that the map used for estimating the geological diversity is inadequate for this purpose or the procedure used to standardize the geology in terms of time-petrographic units is incorrect.