The Global Factors of Lead–Zinc Ore Formation

Resumo

The tectonic evolution of the Earth is the leading factor that accounts for the uneven distribution of lead and zinc reserves through geologic time. The cyclic changes in lead–zinc ore formation productivity reflected the periodic amalgamation of most continental crustal blocks and supercontinent formation, stabilization, and eventual breakup. Many features of the age spectra of lead and zinc reserves are caused by the gradual growth of the continental crust as a result of the accretion of island arcs to the cratonic nuclei, the widening extent of the ensialic environments of ore formation, and the increasing role of the continental crust in magma generation processes.