中国西部干旱区沙漠形成演化综述Ⅰ

A summary of the desert formation and evolution in west China Ⅰ

晚新生代亚州内陆干旱化作为过去全球变化研究的重要组成部分,一直以来是古环境研究中的热点问题。基于对中国西部风尘沉积序列与沙漠内部及周边地层、地貌等地质证据的分析,总结了塔克拉玛干、古尔班通古特、库姆塔格、巴丹吉林、腾格里和毛乌素等沙漠/沙地的形成和演化过程。认为塔克拉玛干沙漠自3.4 M a出现之后,在2.8 M a进一步扩张,其他沙漠直到晚早更新世-中更新世才开始出现,最终形成现在的分布格局,呈现明显的由西向东阶段式扩展模式。

Asian interior Aridification is a hot topic in the palaeoenvironment research. In light of the Aeolian deposits and geomorphology evidencesin and around the deserts in west China, this paper summarizes the formation and evolution patterns of Taklamakan, Guabntunggut, Kumtag, Badain Jaran, Mu Us desert/sand. It is concluded that the initial Taklamakan formed at about 3.4 Ma and expanded at about 2.8 Ma while others deserts/sand are generally believed to appear during late or early Pleistocene and Miocene. Deserts tend to expand from west to ease and their expansion and evolution are influenced by the uplift of Qinghai-Tibet Plateau, the evolution of Arctic icecap and the disappearance of Tethys. Meanwhile, the driving mechanism is not intelligible enough and further study on it is expected.