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利用光释光测年技术对毛乌素沙地和浑善达克沙地7个地点的沉积剖面进行了年代测试,结合地层特征,获得了最近60kaBP以来两个沙地沙丘固定与活化时间的年代学控制60kaBP以来毛乌素沙地的固定期分别为距今37.71ka、8.54ka、8.32ka、7.93ka、7.77ka、7.57ka、7.39ka和2.39ka以后;活化的时间分别为距今57.08ka、52.50ka、13.65ka、13.13ka、7.20ka前后、2.39ka以前和0.29ka以来。在10.97kaBP、10.04kaBP、9.81kaBP和8.67kaBP前后沙地处于气候干湿交替时期。全新世期间,浑善达克沙地在距今8.74～8.72ka、7.79ka前后,沙丘活化;5.69kaBP、4.25kaBP、2.75kaBP、1.53kaBP和0.71kaBP前后,沙丘处于相对固定阶段,0.15kaBP以来,沙丘处于半固定状态。晚第四纪气候千年至百年尺度的变化可能是两个沙地沙丘活化与固定的主导因素。
Sedimentary profiles of seven locations in the Mu Us Sandy and Hunshandake Sandy Lands were tested by using optical dating technique. Combined with the stratigraphic characteristics, the chronology of sand dune fixation and activation time since the last 60 ka BP was obtained The control period of the Mu Us sandy land since the 60 ka BP was 37.71 ka, 8.54 ka, 8.32 ka, 7.93 ka, 7.77 ka, 7.57 ka, 7.39 ka and 2.39 ka, respectively. The activation time was 57.08 ka, 52.50 ka , 13.65ka, 13.13ka, 7.20ka, 2.39ka and 0.29ka. Sands at 10.97 ka BP, 10.04 ka BP, 9.81 ka BP and 8.67 ka BP were in alternate dry-wet climate periods. During the Holocene, the dune was activated in the Hunshandake Sandy Land from 8.74 to 8.72 ka and 7.79 ka ago, and the sand dunes were relatively fixed at 5.69 kaBP, 4.25 kaBP, 2.75 kaBP, 1.53 kaBP and 0.71 kaBP. After 0.15 kaBP , Dunes in a semi-fixed state. The variation of Late Quaternary climate from the millennium to the centenary may be the dominant factor in the activation and fixation of sand dunes in the two sandy areas.