Characteristics And Causes Of Landform Factor In The First Bend Area Of ​​Changjiang River Based On

The third longest river in the word is Jinsha River-which is the upper reaches ofthe Yangtze River,it is in the shape of ‘W’ and flow to the east.Although the river onthis strange pattern formation and evolution studies continued more than acentury.Due to the natural, scope of attention by researchers and limit ofawareness,the research focuses on local sites in Panzhihua, and has not been lookingfor a reliable relevant evidence on landforms and sedimentary.In the recent,theresearch data shows,formation age of each segment of Jinsha River Basin are notconsistent,river evolution may have some regularity,we need to strengthen researchon some of the key river to figure it out.This paper, by using DEM images, system related geomorphic parameter in thestudy area, the extraction of top drag on jinsha river, Sanjiangkou macro landscapebackground and river landscape development characteristics were analyzed. In theprocess of parameter extraction of some basic geomorphic parameters (such astopographic relief, slope, river branch coefficient, complete, etc.) for extraction andanalysis; Combined with the geological structure background of the research regionare discussed, finally it is concluded that:Through statistical analysis waviness and slope in the study area we revealedthat:There is obvious geomorphologhical differences in the local geographicarea,and the edge area shows the characteristics of high grade, high relief;Slope andtopography of the central region is relatively slow,and the study area first increasedand then decreased first increased and then decreased.By extracting the three secondary geomorphic unit boundaries of study area,weget bottom elevation and peak elevation map of the inside unit,we find differencesbetween tectonic uplift of the region led to different potential on each segment,riverneed adjust in order to achieve its dynamic equilibrium,than has different speed to cutand formation different degree. Macroscopically, the river is relatively developing inthe shape of ‘V’,having strong river bed scour,but the river Xiaozhongdian unit showed a low number on the waviness. Microscopically, the waviness and slop hascharacteristics which is increased first and declined with increasing elevation.By obtain the quantitative of the length and the branching ratios on east side ofthe branch of Jinsha river,which is based on DEM,we think the east side of the branchof Jingsha River is not fully development or the new born,and the developmentdegree of the tributaries on the east side of the branch of Jingsha River is less thanthat of the west.Due to the different control of structure in the process of each river,the characteristics of geomorphological parameters on both sides of the branch ofJiasha River in study area indicate the rapid uplift and subsidence movement ofstructural zones since late Cenozoic, and caused the difference of development degreein the two sections which is separated by Shigu area.Upon the Shigu located the transfer zones between Variscan and Indo-fold,it isobviously controlled by tectonic movement,that make area,perimeter and otherparameters evenly distributed on the east side of the branch of Jingsha River.Underthe Shigu,there are many tributary length is very short,and almost flow vertically intothe Jinsha river,this proves that from another perspective may be the Jinsha river is anewly developed after the river capture. That will provide important scientificevidence and perspectives to the geomorphic history, paleoenvironmental evolution inthe study area.