Early Paleozoic tectonic evolution of the North Qinling Orogenic Belt in Central China: Insights on continental deep subduction and multiphase exhumation

New evidence suggests that the Qinling Complex is a tectonic complex rather than a uniform stratigraphic unit or a microcontinent as previously believed, and is mainly composed of the exhumed HP-UHP metamorphic rocks, deep subduction- exhumation-related magmatic rocks and the early Neoproterozoic granites together with the host rocks from the over-riding plate at an active continental margin. The early Paleozoic tectonic history of the NQB includes oceanic slab subduction and formation of arc, backarc spreading, continental deep subduction, arc-continent collision, break off, and multi-stage exhumation of the deep subducted slab, as well as extension and thinning and associated erosion and deposition.