Dynamics of the Early Cretaceous lithospheric thinning and destruction of the North China craton as the consequence of Paleo-Pacific type active continental margin

Early Cretaceous tectonic evolution of the North China craton (NCC) provides a case study for continental remobilization. The mechanism and dynamic processes of lithospheric extension, thinning, and destruction remain hotly debated in the last decades. Extensive Early Cretaceous extensional structures and magmatic rocks in Liaodong and Jiaodong extensional provinces, eastern NCC, including the Liaonan and Wulian metamorphic core complexes, are ascribed to the coupled or decoupled crust-mantle detaching during intensive lithospheric thinning and can be reasonably explained by parallel extension tectonics (PET) model. Sharing similarities in spatial-temporal extension, kinematic features, and dynamic processes, such tectono-magmatic events also widely occurred in eastern Eurasian, from south China, through north and northeast China, to Russian Far East, which is related to the large-scale tectonic extension of regional lithosphere. Realizing the widespread occurrence of extensional tectonics and associate magmatic rocks in eastern Eurasian continent and the narrow arrangement of Early Cretaceous accretionary complexes to its east margin, we defined a new kind of compressive plate boundary, namely the Early Cretaceous Paleo-Pacific type continental margin related to ocean-continent subduction. Being different from other ocean-continent type subduction zone (e. g. , the western Pacific-and Andean-type subduction zone), no remarkable magmatic arcs were found for the Paleo-Pacific one. The stratified convection in mantle depth may provide key force for interaction between the Paleo-Pacific Ocean and Eurasian continent, continental extension, and cratonic thinning and destruction, while plate boundary forces (e. g. , slab-pull and range-push forces) just act as assistants. © 2022 Geological Society of China. All rights reserved.