Research On Paleochannels In The Central And Southern Of Songliao Plain Based On Multi-source Remote Sensing Data

Carrying out the relevant research on paleochannels can not only provide the necessary basic data for the national economic construction,but provide a scientific basis for studying the evolution of the local geographic environment.In addition,it provides certain service for the developments of tourism,agriculture,land resources,engineering planning and design,etc.In this paper,we get the evolution of water system since the Quaternary in the central and southern Songliao Plain by studying the relationship of the paleochannels and Neotectonic Movement.We also analyzed the impact on the local ecological environment from the evolution of water system.This paper reveals the mechanisms of the current severe ecological environment in the study area from the perspective of the geological environment evolution,which provides directions for solving the local ecological and environmental problems such as land desertification and soil salinization.This paper uses multi-source remote sensing data to extract the paleochannels information in the central and southern Songliao Plain.The article discussed the relationship of Neotectonic Movement,water system evolution and paleochannels according to the characteristics of the Neotectonic Movement since Quaternary,distribution characteristics of the paleochannelss and its old-new relationship in the study area,and explained how the neotectonic movement controls the evolution of the water system since the Quaternary.Through research and analysis,we get the following achievements:1.We extract the surface and shallow buried paleo-chaanel information through the image enhancement processing such as data fusion,band combination,histogram equalization and principal component analysis on Landsat TM image,Landsat8 OLI image and Sentinel-2A image in the central and southern Songliao Plain,combined with DEM data generation research in the study area.And a set of remote sensing image processing flow is established for extracting bare and shallow buried paleochannels information,which is based on multi-source remote sensing data in the central and southern Songliao Plain.2.According to the characteristics of the topographic and remote sensing images in the study area,a set of visual interpretation processes was established for extracting paleochannels information by using remote sensing images,which is as follows: There are bead-shaped modern water bodies such as lakes,blisters,or ponds;there are also irregular linear shapes whose color tone is significantly different from the surrounding features;and some paleochannelss are linear groove-shaped and still carry current discontinuous water.3.Neotectonic movements play an important role in the evolution of the water system in the study area.One of the controlling factors of the evolution of water system is the local topographic and landform changes,and the evolution of the landform since the Quaternary is mainly controlled by the neotectonic movement in the study area,thus we concluded that the effect of neotectonic movement is one of important factors that lead the evolution of water system in the central and southern Songliao Plain.The characteristics of neotectonic movements in the study area are mainly manifested as the strong movement of volcanoes and the differential up-and-down movement of fault blocks.Through the analysis of the characteristics of the neotectonic movement in the study area and its relationship with evolution of the water system and paleochannelss,we confirmed that the water system since the Quaternary in the central-southern region successively experienced a centripetal paleo-large lake since Middle Early Pleistocene to Late Mid-Pleistocene(caused by the continuous decline of the Songliao fault depression basin and the slow uplift of the mountains around the basin),Large outflowing river running from north to south during the Late Pleistocene(the Songliao Watershed and Songliao Plain were lifted slowly and asynchronously due to the Neotectonic Movement),The current water system distribution pattern formed by the continuous uplift of Songliao watershed after the late Pleistocene.The study of the evolution of water system since the Quaternary in the central and southern Songliao Plain has a certain reference value for improving the local ecological status,and can provide guidance for formulating related improvement measures.