Rock chemistry and fluid inclusion studies as exploration tools for ore deposits in the Sila batholith, southern Italy

The Sila batholith is the focus of an extensive petrogenetic research program, which includes an assessment of its potential to host granite-related ore deposits. Univariate and multivariate statistical techniques were applied to major- and minor-element rock geochemical data. The analysis indicates that the highest potential for mineralization occurs in corundum-normative, peraluminous, unfoliated, relatively late-stage plutons. The plutons are enriched in Rb, Nb, Ta and U, but depleted in Fe, Mg and Sr. The K/Rb, Ba/Rb, Rb/Sr and Rb³/Ba·Sr·K indices and high R-factor scores of Si-K-Rb are typical of mineralized granitic rocks.

A reconnaissance fluid inclusion study indicates that the sub-solidus rock was infiltrated by solutions of widely different temperatures (50–416°C) and variable salinities (0 to ∼26 wt.% NaCl equivalent). The higher-temperature solutions probably represent granite or magmatic-related Hercynian fluids, whereas the lower-temperature fluids may be either Hercynian or Alpine in age. Fluids with characteristics typical of mineralized “porphyry” systems have not been recognized.