PROTO-SEDIMENT BASIN TYPES AND TECTONIC EVOLUTION IN THE SOUTHERN EDGE OF NORTH CHINA PLATE

Type of ancestral basin in the Southern North China plate is controlled by tectonic evolution. The North China and Yangtze plates changed from open to close during the Paleozoic era to Middle Triassic epoch. The southern edge of North China Plate changed from passive continental margin(Z-O₂) to uplift denude(O₃-C₁), then to foreland flysch basin(C₂-P₂).The two plates collided and formed the famous Central Orogenic Belt(T₃-J₁) and coupled molasses sedimentary basin. From the Middle Jurassic to Early Cretaceous, postkinematic inner-orogenic belt subsided while orogenic belt margin detached, forming complex structures of backlimb thrust and front detachment. Detached fault-depression and down-warping basin came into being, controlled by activities of the Palaeo-Pacific plate and Pacific plate in late epoch. Different type of ancestral basin in different time is important for oil-gas exploration.