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用热释光测年方法对陕西榆林地区蔡家沟和石峁剖面的风成砂－黄土－古土壤序列进行了系统的测年，结果表明末次冰期的风成沉积中夹有三层古风成砂，由此反映了末次冰期中有三次沙漠扩大的气候干旱时期。根据年代测定结果最末一次干旱事件出现在１２～＜２７ｋａＢ．Ｐ．之间，基本上与末次冰期极盛期相当，可以与深海氧同位素阶段２对应。第二次干旱期出现在４８ｋａＢ．Ｐ．左右，大致与氧同位素阶段３的中期相当。最早的干旱期出现在５５～＜７５ｋａＢ．Ｐ．之间，与阶段４对应。令人感兴趣的是虽然与阶段２、阶段４对应的干旱期在世界上其它地区同样有记录，但是大致相当于阶段３中期的这期干旱事件却以榆林剖面反映最好，表现为末次冰期的间冰段期间，毛乌素沙漠也曾经大规模扩大，这从一个侧面说明了中国的沙漠－黄土边界带对气候变化的敏感性。此外，热释光测年结果还表明了末次冰期的沉积由风成砂与黄土迭覆而成，而末次间冰期则由古土壤与黄土迭覆而成，因此，无论是冰期还是间冰期，气候条件都不是以持续的干冷或温暖为特点，而是叠加了更次一级的气候变化。毛乌素沙漠在第四纪时期并非持续存在，而是在气候的调节下经历了沙漠出现与固定的多次转变
The dating of aeolian sand-loess-paleosol sequence of the Caijiagou and Shijie sections in Yulin area, Shaanxi Province was systematically measured by the thermoluminescence dating method. The results show that there are three Paleozoic sand-forming sandstorms in the glacial deposition in the last glacial period , Thus reflecting the drought period of three climates during the last glacial period. According to the dating results of the last drought event occurs in 12 ~ <27kaB. P. Basically equivalent to the last glacial ebb and phase, corresponding to the deep sea oxygen isotope phase 2. The second drought occurs at 48kaB. P. Approximately equal to the mid-stage of the oxygen isotope phase 3. The earliest drought occurred in 55 ~ <75kaB. P. Between, and phase 4 corresponds. It is interesting to note that although the drought periods corresponding to phases 2 and 4 are also recorded in other parts of the world, the drought event, which is roughly equivalent to the middle stage of phase 3, is best reflected in the Yulin section and is characterized by the last glacial period During the inter-ice section, the Mu Us Desert has also been large-scale expansion, which shows from one side of China’s desert - loess boundary zone sensitivity to climate change. In addition, the results of thermoluminescence dating also show that the deposition of the last glacial period was formed by the aeolian sand and loess, while the last interglacial was formed by the overlaying of the ancient soil and the loess. Therefore, both the glacial and interglacial periods, Climatic conditions are not characterized by continued dryness or warmth but rather with a more subordinate climate change. The Mu Us Desert did not persist in the Quaternary period. Instead, it experienced many changes in the appearance and fixation of desert under the regulation of climate