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野外调查中在晋西北地区首次发现了马兰黄土中的古风成砂沉积，其机械组成主要是极细砂和细砂，而且具有明显的风成交错层理等特征。结合年代资料和孢粉分析，认为古风成砂形成于２７０００～１００００ａＢ．Ｐ．间的末次冰期盛冰期，当时晋西北地区是干旱荒漠－干草原景观，气候寒冷干燥，风的地质作用成为控制该区环境变化的主要动力因素，沙漠化土地迅速扩展或沙漠大范围地南侵，说明该区土地沙漠化过程至少在晚更新世晚期就已断续存在
In the field investigation, paleomagnetic sand deposition in the Malan loess was first discovered in the northwest of Shanxi Province. Its mechanical composition is mainly fine sand and fine sand, and has obvious characteristics such as wind stratification. According to the age data and sporopollen analysis, it is considered that the paleosmosis sand formed at 27000 ~ 10000aB. P. During the last glacial ice-filling period, the northwestern Shanxi was an arid desert-steppe landscape where the climate was cold and dry, and the wind’s geological role became the main driving force for controlling environmental changes in the area. The rapid expansion of desertified land or the extensive southward invasion of the desert demonstrated that The process of desertification in the area has been discontinued at least in the late late Pleistocene