THE EVOLUTION OF MESOZOIC-CENOZOIC BASIN-MOUNTAIN STRUCTURE IN THE EAST YANSHAN AREA AND XIALIAOHE BASIN

The author discussed the pre-Mesozoic structure background and the Mesozoic-Cenozoic basinmountain structure evolution in the east Yanshan area and Xialiaohe Basin. The author considers that the Mesozoic-Cenozoic structure evolution process in the east Yanshan and Xialiaohe Basin is a alternate process of intracratonic (intracontinental or intraplate) basin-mountain structrue and compression structure in the basement of pre-Mesozoic North China Craton lithosphere. It experienced five periods of basin-moun-tnin evolution(Early and Middle Triassic, Late Triassic to Early Jurassic, Middle and Later Jurassic,Cretaceous and Cenozoic) and five compression deformation stages (the end of Middle Triassic, Early Jurassic, Late Jurassic, Cretaceous and Paleogene). The compression not only resulted in withering or disappearing of the early basins, but also made them deform or be responsible for the basin reversion. The extensions in Middle and Late Jurassic, Cretaceous and Cenozoic resulted in Middle and Later Jurassic fault basin, Cretaceous fault basin and Cenozoic rift basin. The compression and extension appear alternatively, associated Compression structures and extensional structures developed alternatively in the process.