Neoproterozoic subduction-related active rifting in the South China Craton: insights from geochemical and zircon Hf isotopic data

Active and passive continental rifts are generally attributed to plume subduction mechanisms, respectively. However, controversy surrounding the role of two mechanisms continues, especially for mid-Neoproterozoic in South China Craton. Here, we use geochemical zircon Hf isotope data from craton’s rift successions examine mechanism rifting. The compiled support existence subduction-related magmatic belts along Jiangnan Orogen western Yangtze margin craton during mid-Neoproterozoic, consistent with a conventional mechanism. But evidence asthenospheric upwelling subsequent lithospheric uplift, metamorphism, volcanism magma-rich infill indicate rifting was active. Compiled εHf(t) values crustal incubation times suggest ca. 830–780 Ma transition advancing retreating that coincides across craton. We therefore propose active model which onset transitionalsubduction triggered mantle convection activity led initiation This suggests mixed rather than distinct end-members.