The Cenozoic tectonic evolution of the Great North China: two types of rifting and crustal necking in the Great North China and their tectonic implications

Abstract The Great North China underwent widespread continental rifting during Cenozoic time that caused extension and necking of the crust in this area and formed four major rift systems. In this paper we provide geological and geophysical evidence that rifting and extension in the western part of the Great North China differs from that in its eastern part in age and nature. The space-time relationships show that the origins of the Western Rift Group of the Great North China are probably related to the Tibet Plateau tectonics, whereas those of the Eastern Rift Group are related to the subduction events in the western margin of the Pacific Plate. Furthermore the Quaternary tectonic regime in the eastern part of the Great North China differs from the Neogene tectonic pattern and shows relations with western rifts. We speculate that during the Quaternary, the processes that caused rifting in the west have spread further east and now affect the eastern part of the Great North China.