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位于青藏高原西北部的西宁盆地沉积了年代序列跨度非常长的连续的新生代地层.这些地层序列记录了有关青藏高原隆升历史及其相关气候变化的丰富信息.本研究获得了西宁盆地谢家剖面较高分辨率的正构烷烃生物标志化合物和孢粉记录.整合正构烷烃和古孢粉记录揭示:在50.2～28.2Ma之间,西宁盆地经历了长期的降温过程,明显的生态事件发生在37.5～32.7Ma之间.自此盆地中的植被呈现显著的垂直地带性变化:较低海拔处生长旱生灌草类植物,中海拔地带生长亚热带阔叶树,高海拔带生长针叶林.这些植被和气候的变化有可能是对始新世早期气候最适宜期之后长期的全球降温事件和早新生代北部青藏高原周围山地隆升事件的共同响应.
The Xining Basin, located in the northwestern part of the Qinghai-Tibet Plateau, has deposited successive Cenozoic strata with very long-term spans, and these stratigraphic sequences record abundant information about the uplift history of the Tibetan Plateau and its associated climate changes. High-resolution n-alkanes biomarker profiles and sporopollen recording of the profiles. The integration of n-alkanes and ancient sporopollen records revealed that the long-term cooling process and significant ecological events occurred in the Xining basin between 50.2 and 28.2 Ma Between 37.5 and 32.7 Ma, and the vegetation in the basin showed a remarkable vertical zonal change since this time: the growth of xerophytic herbaceous plants in lower elevations, the growth of subtropical broad-leaved trees in mid-altitude and the growth of high-coniferous coniferous forests Changes in vegetation and climate are likely to be common responses to the long-term global warming events following the most favorable Eocene climate and the uplift of the mountainous areas around the Tibetan Plateau in the north of the Early Cenozoic.