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重建干旱地区洪积成因戈壁的形成历史能够揭示控制洪积作用时空演化的构造、气候变化.对额济纳盆地不同地貌单元的戈壁石英砾石宇宙成因核素10Be浓度的测量和暴露年龄的估算表明,盆地北缘戈壁阿尔泰洪积平原上的戈壁至少在420ka前就已出现;而盆地内黑河流域洪积平原上的戈壁则形成于约190ka以来,并逐步向北和向东现代低海拔、尾闾湖方向发展,这种演化趋势可能是在青藏高原隆升和盆地内构造活动的影响下洪积作用和洪积扇发育空间变化的结果;420ka以来气候冰期/间冰期的冷暖旋回造成的周边高山地区冰川的前进与后退,可能主导了盆地洪积作用的强弱变化和水体的大小,大规模、高能量的洪水主要发生在高山冰雪消融时期(冰消期),可能也是盆地水体最大时期.
The history of the formation of the Gobi genesis in the arid region can reveal the temporal and spatial evolution of the structure and climate change that control the alluvial accumulation.The estimation of the 10Be concentration and the age of exposure of the Gobi quartz gravel in different geomorphic units in the Ejina basin shows that the basin The Gobi in the Altai floodplain in the northern margin of the Gobi Basin occurred at least 420 ka ago; while the Gobi in the alluvial plain of the Heihe Basin in the basin formed around 190 ka and gradually moved north and east to the modern low elevation. This evolution trend may be the result of the alluvial accumulation and the development of alluvial fan under the influence of the Qinghai-Tibet Plateau uplift and the tectonic activity in the basin. The surrounding alpine region caused by the cold-warm cycles of climate glacial / interglacial since 420 ka The advance and retreat of the glacier may have led to the change of the intensity of the alluvial basin and the size of the water body. Large-scale and high-energy floods mainly occur during the alpine glacier-ice melting period (ice age) and may also be the maximum period of the basin water.