Reserve base in relation to crustal abundance of metals: another look

Abstract

When the global "reserve base" (instead of global "reserve") of common metals is considered in relation to their average abundance in the upper continental crust (instead of the bulk continental crust), a striking regularity is revealed. Twenty five common metals considered here fall along four well-defined essentially parallel lines in a "reserve base" versus average abundance diagram. The pattern is inferred to be the reflection of a persistent, first-order control of average abundance over "reserve-base" modified by such factors as: (a) differential preservation potentials of genetic varieties, (b) order-of-magnitude difference in the required "enrichment factors" of the metals, and (c) differential geochemical "adaptability" and "insularity" of the metals. Positive and negative deviations of three of these lines from the main trend line (MTL) can be explained almost quantitatively. Their lateral shift, maintaining near-parallelism with the MTL reveals a fundamental relationship that is neither masked nor distorted by the modifying factors, and distinguishes groups that are more closely related in their response to the modifying factors.