The West Kunlun region forms the northern margin of the Tibetan Plateau, and sedimentation in this region contributed to plateau formation and its northwards expansion, as well as the development of central Asian aridification. However, the stratigraphic dating framework in this region has been ambiguous, hampering the understanding of both tectonic and environmental evolution. Here, palynological analysis was performed on the Xialafudie Formation in the West Kunlun region. Together with the palynological assemblage and megafossils found in the study section, as well as regional stratigraphic comparison, we conclude that the Xialafudie Formation was deposited during the Pliocene, and not Early Cretaceous as previously reported. The palynological assemblage of the section is mainly composed of drought-tolerant herbs and shrubs, and the percentage of conifers and broadleaved trees is very low, indicating that a dry and cold environment prevailed in the West Kunlun region during the Pliocene. Comprehensively analysed palynological data from the Tarim Basin and its surroundings show that aridification intensified in this part of central Asia during the Pliocene, as a result of long-term global cooling and regional tectonism.

西昆仑地区形成了青藏高原的北缘，该地区的沉积促进了高原的形成及其向北扩张，以及中亚干旱化的发展。然而，该地区的地层测年框架一直模棱两可，妨碍了人们对构造和环境演化的理解。在这里，对西昆仑地区下阿拉夫底组进行了孢粉学分析。连同在研究部分发现的孢粉组合和巨型化石，以及区域地层对比，我们得出的结论是，Xaalafudie组沉积在上新世期间，而不是先前报道的早白垩世。该部分的孢粉组合主要由耐旱的草药和灌木组成，针叶树和阔叶树的百分比非常低，表明上新世时期西昆仑地区普遍存在干燥和寒冷的环境。对塔里木盆地及其周围地区的古生物学数据进行了综合分析，结果表明，由于全球长期冷却和区域构造运动，上新世期间中亚这一地区的干旱化加剧。