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Morphological and sedimentological characteristicsof Nitrarianabkhas and implications for the analysis of their formation processes, in minqin China

Kejie Zhan1 ,2, Zihui Yang 2, Ning Huang1
1Lanzhou University, Lanzhou Gansu, China, 2Gansu Desert Control Research Institute, Lanzhou Gansu, China

Nabkhas are the most frequent aeolian deposits in desertifiedsteppe and desert,they play an important rolein the stability of sand dune and the restoration of degraded desertecosystems,but theirformation processesremain poorly understood. By analyzing the morphology, erosion and cumulative, sediment grain size ofNitrarianabkhas in Minqin China,discussingtheir relationship with thesub-surfacestructure of existing "mature " one, we have been able to clarify its development and evolution processes. The height, width andtotal length of nabkhas show positive correlation, but the ratio of leeward side length towindward side length reduces with theheight ofnabkhas. The mean size of the sediment particles on the surface decreases with enlarge of the nabkhas body. The sizes of particles on leeward andwindward sides alternately changes with the reversed wind direction. We then dig a profile of the nabkhas and find all of abovelawscan beverified by the internal sedimentarystructures.