Geochronology of mercury, tin, and fluorine mineralization in northern Mexico

This study was undertaken to obtain reconnaissance isotopic ages on tin, mercury, fluorine, and antimony mineralization in northerm Mexico and to determine their temporal relation to the metallogenic evolution of the continental volcanic arc in this region. Deposits were dated using conventional K-Ar and ⁴⁰Ar/³⁹Ar analyses of whole rocks and phenocryst separates for altered and unaltered pre- and postore samples. The results demonstrate that the Sn-Hg-F-Sb mineralization was essentially contemporaneous with the latest phases of base and precious metal mineralization in northern Mexico and suggest that formation of deposits containing these metals is a special stage in the metallogenic evolution of volcanic arcs, which requires a relatively thick crust that is conducive to extensive magmatic differentiation and silicic volcanism. -from Authors