Geochronology and Geochemistry of the Heping pluton: Constraints for Early Paleozoic tectonic evolution of Cathaysia Block, South China

  • Date

    April 10,2018

  • Time

    4:00-4:20 PM

  • Venue


  • Speaker

    Miss XIE Yuexin Department of Earth Sciences, HKU

The South China Craton is initially formed by amalgamation of the constituent Yangtze and Cathaysia Blocks in the Neoproterozoic. In the early Paleozoic, the craton recorded a regional tectono-magmatic event involving hiatus of sediment accumulation interspersed with magmatism, deformation, and magmatism. The tectonic setting of the South China Craton during early Paleozoic time has been the focus of recent debate, with different models advocating intracontinental collision or plate subduction. Widespread early Paleozoic granitic plutons are distributed in the Cathaysia and southeast Yangtze Blocks, but their petrogenesis is unclear, especially those with I-type granite affinities. The early Paleozoic Heping granodioritic pluton in southern Cathaysia contains considerable mafic microgranular enclaves (MMEs), indicative of magma mixing. The host granodioritic and MMEs samples from the Heping pluton yield consistent zircon U-Pb ages of ~446 Ma and show a large variation in zircon εHf(t) values from -4.28 to -11.59 and from -0.87 to -13.68, respectively. New data, along with ages and geochemical patterns across the craton, will provide new insights into the early Paleozoic tectonic evolution of the South China Craton.