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临夏盆地位于青藏高原东北边缘,记录了青藏高原隆生过程中的大量构造事件和气候事件。碎屑颗粒磷灰石裂变径迹热年代学方法揭示出临夏盆地记录的2次青藏高原隆升的时间,分别为约14MaBP和约5.4～8.0MaBP。其中,约14MaBP的快速剥露事件可能反映青藏高原北部由于岩石圈对流减薄而发生的地壳增厚、高原隆升事件;约8.0～5.4MaBP的构造活动可能与高原隆升到相当高度后,由于维持其巨大高度和继续调节南北会聚的需要,青藏高原的东北边界向东向北扩展有关,而控制中国大陆强震活动的活动地块构造格架可能于约8.0～5.4MaBP开始形成。
Linxia Basin is located on the northeastern margin of the Qinghai-Tibet Plateau, recording a large number of tectonic and climatic events during the uplifting of the Qinghai-Tibet Plateau. Apatite fission track climatological dating of detrital particles revealed the time of two uplift of the Qinghai-Tibet Plateau recorded in Linxia Basin at about 14MaBP and about 5.4 ~ 8.0MaBP, respectively. The rapid detachment event of about 14MaBP may reflect the crustal thickening and uplift of the plateau due to the thinning of the lithospheric convection in the northern part of the Qinghai-Tibetan Plateau. The tectonic activity of about 8.0-5.4MaBP may rise to a considerable height after the plateau uplift, Because of its great height and the need to continue to regulate the north-south convergence, the northeastern boundary of the Qinghai-Tibet Plateau extends eastward and northward. The tectonic framework of the active mass controlling the strong earthquakes in mainland China may be formed at about 8.0-5.4MaBP.