The controls of the collisional orogenesis in the Qinling Mountains on the Carboniferous-Permian transgressional processes in North China

The Late Palaeozoic-Triassic is the collisional orogenic period of the major orogenesis in the Qinling orogenic belt,where the collisional orogenesis operated in the forms of point contact and plane contact during the Carboniferous-Permian when four phases of large-scale transgressions once occurred in North China,including C₁²-C₂^1-1,C₂^1-2-C₂²,P₁¹ and P₃¹,respectively,The research of sedimentary facies and palaeogeographic mapping and spatial distribution of the transgressional depositional units indicate that the transgressions originated in the Qinling residual sea basin south of the North China block,and progressively prograded from east to west. These transgressional processes are generally governed by both the palaeogeographic framework of the North China block being higher in the west and lower in the east,and shear reverse diachronous collisional orogenesis centred by the Xiaoqinling region within the Qinling orogenic belt.