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巴丹吉林沙漠位于中国内蒙古自治区的西部 ,是中国第三大沙漠。过去通常认为该沙漠中沙丘的可能沙源来自附近的各种沉积物和岩石 ,包括弱水河扇的沉积物 ,弱固结的二叠纪页岩、白垩纪砂岩和砾岩以及戈壁阿尔泰的古老岩石。根据对风成砂的粒度观测 ,有证据表明在沙漠内部的风成砂沉积朝东南方向具有较弱的但又确实的变细趋势。这与沙丘横脊线的SW -NE向排列以及坡面的南东指向是一致的。因此 ,可以认为西北部的弱水河冲积扇是巴丹吉林沙漠风成砂的最可能的沙源。在西北部风成床沙覆盖了较老弱水河扇起源的冲积物。这种沉积物的热发光测年范围在 190～ 10 0kaBP之间。由于测量中对沉积物漂白可能不完全以及对其中平均古水含量估算均存在不确定性 ,同时由于对沙漠该地区风成作用开始之前堆积的沉积物进行了测年 ,这一数据范围代表了最大的年龄。另外三个风成砂测年结果分别接近 133 6 6和 2 2ka ,代表有关巴丹吉林沙漠西北部风成作用开始的最小年龄。沙漠的沙丘高度平均为 2 0 0～ 30 0m ,但在东南部偶尔可达 4 5 0m。一些学者曾提出风成床沙覆盖了一个陡峭岛山突起的假说 ,来解释这些异常的空间。本次研究发现 ,在研究区之下是一个产状水平的白垩纪扇砾岩和砂岩的台地 ,可以断定在沙漠东南部呈现台地地貌
Badain Jaran Desert is located in the western part of Inner Mongolia Autonomous Region of China and is the third largest desert in China. In the past, it was generally considered that the possible source of sand in the dunes in the desert came from a variety of nearby sediments and rocks, including the sediments of weak-water river fans, weakly consolidated Permian shales, Cretaceous sandstones and conglomerates, and Gobi Altai Ancient rock. Based on the observations of the size of the aeolian sand, there is evidence that the aeolian sand deposits within the desert have a weaker but surely thinning trend towards the southeast. This is consistent with the SW-NE alignment of dune ridgelines and the south-easterly orientation of the slope. Therefore, it can be considered that weak river alluvial fan in the northwest is the most probable source of sand in the Badain Jaran Desert. In the northwestern winds the bed of sand covers the alluvial deposits of the older weak river fans. The thermal luminescence dating of this sediment ranged from 190 to 100 kaBP. Because of the possible incompleteness of bleaching in the measurements and the estimation of the average paleo-water content in the measurements, and because of the dating of sediments accumulated prior to the start of the aeolian desert in the area, this data range represents The oldest age The results of the other three aeolian sand dating to 133 6 6 and 22 ka, respectively, represent the minimum age at onset of wind-forming effect in the northwestern Badain Jaran Desert. Sand dunes in the desert average a height of 200-3000 meters, but in the southeast occasionally up to 405 meters. Some scholars have suggested that the bedrock of sand covered the hypothesis of a steep island hill that explains these anomalous spaces. The study found that below the study area is a tectonic Cretaceous fan conglomerate and sandstone platform, we can conclude that in the desert southeastern terrain