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通过对柴达木盆地西部(简称柴西地区)的干柴沟背斜南西翼的西岔沟层型剖面进行系统测制和2～3m等间隔磁性地层学、磁化率各向异性系统采样,并进行精确测量,利用在该区建立的高分辨率、高精度磁性地层年代资料,结合沉积学等研究,讨论了磁化率各向异性参数变化趋势对环境的指示,并揭示在约23～6.2Ma期间环境演化经历了三个阶段:Ⅰ阶段(22.4～13.4Ma)为湿润环境;Ⅱ阶段(13.4～8.2Ma)为温干环境向干冷转型;Ⅲ阶段(8.2～6.2Ma)气候转冷变干且变化更复杂。认为7.8Ma以来气候转型及有规律的变化与现代季风形成有关。为青藏高原的隆升过程及其环境效应提供可靠资料。
By systematically measuring the stratigraphic features of the Xichachao-type profile in the southwestern part of the Qianchaigou anticline in the western part of the Qaidam Basin (the western Qaidam basin for short) and sampling magnetic susceptibility anisotropy systems at 2 ~ 3m intervals, The accuracy of magnetic susceptibility anisotropy parameters is discussed based on the data of the high-resolution and high-accuracy magnetic stratum dating in this area combined with sedimentology. During the period of Ma, the environmental evolution experienced three stages: the first stage (22.4 ~ 13.4Ma) was humid environment; the second stage (13.4 ~ 8.2Ma) was dry and cold transition from warm to dry environment; the third stage (8.2 ~ 6.2Ma) Dry and change more complicated. It is believed that the climate change and regular changes since 7.8 Ma are related to the formation of modern monsoon. Provide reliable information for the uplift process and its environmental effects in the Qinghai-Tibet Plateau.