Late Paleoproterozoic sedimentary rock-hosted stratiform copper deposits in South China: their possible link to the supercontinent cycle

摘要: Giant sedimentary rock-hosted stratiform copper (SSC) deposits commonly occur in rift environments, tem- porally coincident with the breakup of Rodinia and Pangea supercontinents. However, whether or not such have also formed during Paleo- proterozoic Columbia supercontinent is well known. A group dolostone-hosted Cu late Paleoproter- ozoic rift-related sequences Dongchuan Group, South China, form one largest SSC districts world. Being region, Yinmin deposit has orebodies intruded by dolerite dykes. One dyke a SIMS zircon U-Pb age 1,701±28 Ma, slightly younger than ore- hosting strata 1,742±13 Ma for tuff unit. Six chalcopyrite bornite separates from strat- iform contain highly radiogenic Os extremely low common yield weighted mean Re-Os model 1,666±82 187 Os- Re errorchron 1,585±100 Ma. The present sulfide ages thus constrain timing mineralization at ~1,700 and, inference, other arguably represent large-scale event Paleoproterozoic. formation these was coeval initial breakup/fragmentation supercontinent. This study highlights temporal likely genetic links between large-sized cycle.