The Paleoclimatic Signatures of Supergene Metal Deposits

Abstract

Supergene metal deposits host a comprehensive record of climate-driven geochemical reactions that may span the entire Cenozoic. Products of these reactions can be dated by a variety of radiogenic isotopic methods, such as Ar-40/Ar-39, (U-Th)/He, U-Pb, and U-series; The frequency of mineral precipitation, determined by dating a representative number of samples of a particular mineral collected from distinct parts of the supergene ore body, reflects times in the geological past when weathering conditions were condutive to water-rock interaction. The frequency of mineral precipitation through time permits identifying periods in the geological past when climatic conditions were most conducive to chemical weathering and supergene ore genesis.