| The research object of this paper is the basin of Baiyanghe,which is in the West Junggar,xinjiang province. It is90m resolution SRTM which has been Calibrated and spliced and TM2009data as the base map. We extract the water system of the study area though ENVI andARCGIS, combining the quantitative analysis method of the geomorphology, field surveymethods, field investigation and Indoor test methods. Then I determine the boundary of thebaiyang River basin and sub-basin. On this basis, Researching the geometric characteristics ofthe baiyang River Basin, Valley features, water features, and evolution characteristics.The geometric characteristics of baiyang river are as follows: the area of the basin ofbaiyang river is15508km~2, composed of the basin of keledienengsu river, the basin of bulateriver, the basin of taibulekete river, the basin ofwutuwusan river, the basin of baiyang river,the basin of buerkuotai river, the basin of keketale river. The area of each sub-basin is782km~2,537km~2,78km~2,163km~2,5708km~2,1972km~2,926km~2,1740km~2,3597km~2. Thehighest elevation of the study area is2615m, and the minimum elevation of the study area is262m, where is in the lake of Alike. The average elevation of the study area is951m. Weanalyze the geomorphological features of the study area based on river watershed of the studyarea, the geomorphic surfaces altitude, slope and topography4undulation classification index.We divide the study area into nine sub-basin based on the watershed. We divide the study areainto a low-altitude landscape, mid-elevation topography based on the elevation of the studyarea and make a further division. The study area is divided into plain, gently inclined slope,slope, steep slopes, slope-acute, acute and steep, vertical slope based on the slope. The studyarea is divided into plains, plateaus, hills, small undulating mountain, medium undulatingmountain according to the waviness.The geomorphological structure of the study area is distinct. There is obvious zonation ofthe geomorphological structure of the study area. The study area can be divided into fourlandform belt from the upstream to the downstream: the northern mountainous area, thesouthern mountainous area, the landform belt of alluvial fan, the landform belt of alluvialplain. The mid-mountain in the north includes Wuerkeshier and saimisitai, the altitudebetween1800and2400m, the relative elevation difference is600-1000m. The central of themid-mountain kept relatively complete ancient planation surface, the relative elevation difference around50m, river erosion is not strong, the denudation and plane flushing actionbased, residual material developed well, and bedrock exposed bad. The main rivers includeKledienengsuhe River, Bulatehe River, Taibulekete River, Wutuwusanhe River, BuerkuotaiRiver. The diluvial sector position of Central Mountain located in Bai Yanghe which betweenthe mid-mountain in the north and southwest mountain foothills-ironworks groove betweenthe concave ground. Absolute altitude600-1000m, the terrain is relatively flat, mostlydiluvial gravel stone cover, diluvial sector. Pluvial fan is extremely common in the internalstructure of double deck structure, bottom of thick diluvium, across the top of mountain, rivergravel pebbles. Lower pluvial looking for black, poor psephicity, bedding structure complex;Red at the top of the gravel in potassium long granite boulders, roundness is wonderful, thegravel flat surface orientation, thickness is smaller. Upper and lower deposit one black onewhite, comparative and intense. Low in southern hilly land which belongs to and inaccordance with the north face of mount, high in the west and lower in the east. Altitude of1000-1500m in the west and the relative elevation100-200m, belong to low mountain area;The east elevation of700-1000m, relative elevation100m, is a hilly region. Eastern hillyregion basically has no running water all the year round, the western low mountainous area isrelatively small, the discharge of rivers flow velocity is slow, weak erosion. The area’s largestriver is bout river upstream. Impact southeast plains region south of yu hong fans, edge, BaiYanghe downstream, slope of about1-3‰, Bai Yanghe into the plains,400meters above sealevel, river channel is very unstable, form the meander, many abandoned old channel andoxbow lake development. Downstream of the main rivers in this area for Bai Yanghe.The Valley features of baiyang river: the bottom of middle and lower reaches becomeswider and wider, floodplain develops; gravels of valley is high. The gravels of Valley reachesa round or very rounded on both sides of the alluvial fan and alluvial plain, and the shape ofthe valley is “U”. There are4river terraces above the valley slope. The continuity of the first,the second, the forth terraces is good, while The third terrace appears only in some places.The diluviums on both sides of the valley slope can correspond very well. The structure ofdiluviums was divided into upper and lower layers: it is sandy gravel which composed byK-feldspar granite boulders, dark gray volcanic clastic sandstone and conglomerate gravel andso on the upper layers and the gravel roundness, poor sorting. It is sandy gravel on the lower layers too. But the gravel is not roundness and the sorting is rich. The shape of the gravel isSub-angular, sub-rounded. There are Thin coarse sand and sand layers which are horizontalwavy bedding and oblique bedding.in gravel layer.The features of terrace gravel are as follows: each terrace of the baiyang River is mainlycomposed of sandy gravel and a small amount of sandy loam. There are some differencesamong each terrace, but there are more similarities among them. The terraces in the middlereaches of the valley slope are mainly composed of gravel sand, sand and gravel. Thepsephicity of the gravel is good, sub-rounded to rounded. The terraces in the downstreamreaches of the valley slope are mainly composed of gravel sand, sandy loam. The psephicityof the gravel is better, rounded to very rounded. By the particle size analysis of sedimentsamples,we know that multimodal characteristics of the sample particle size is a result offlood removal and deposition of particles of different grain size fractions in the arid zone, orthe weak currents handling fine particulate matter after the coarse particulate matter duringtorrent stage coarse after the flood.Evolution characteristics: the study area occurred at least4times tectonic uplift process.After the planation occurred, planation surface Ⅳ was formed in the northern mountains,andplanation surface Ⅲ can be found in the southern miuntains. planation surfaceⅠ is found inthe peak surface of some middle mountains and high mountains,about altitude2300m;planation surface Ⅱ is on the top of lower mountains, about1800m above sea level;planation surface Ⅲ is the surface of hummocky platform,which is the top surface of lowmountains and hillys,about altitude1300m. planation surface Ⅳ is on the top of the alluvialfan, about1000m above sea level. There were3-4development process of alluvial fanhappened in this basin. According to its Quaternary structure, three kinds of these alluvial fancan be distinguished uder natural conditions. The The earliest alluvial fan is high；then it is themain body of the lower part of the high alluvial fan. The last alluvial fan is some kinds ofsmall alluvial fan which embedded into the earlier one,such as the alluvial fan in the valley ofBaiYang river; or MoHu Tai;or some small alluvial fan before mountains. |
PDF Full Text Request