Study on Quaternary sedimentary environment evolution of Raoyang sag in Central Hebei province

The Quaternary sedimentary environment evolution of Raoyang sag in Central Hebei province is obviously of inheritance and the ancient sedimentary background is of profound impact on it.On the basis of lacustrine basin evolution in paleogene and neogene period,the Quaternary sedimentary sediment provenance comes mainly from the west,next to the northwest,southwest and northeast.The ancient Hutuo river,the ancient Tanghe river and the ancient Caohe river acted as the main medium in sediment transport.The river developed in the process of Paleogene and Neogene,and the lacustrine depositional system still controls the whole study area,and mainly developed four types of sedimentary facie,respectively for blunt(flood)fan facie,fluvial facie,(fan)delta facie and lacustrine facie.In the process of the quaternary sedimentary environment evolution,tectonic movement,climate change(the evolution of the ice age),sealevel change,and etc jointly restrict the evolution of sedimentary environment in different periods.