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笔者在盆 山构造及构造地貌发育的基础上,对研究区构造和沉积记录进行了分析,进而探讨了新生代以来河西走廊与北祁连山的耦合关系。区内盆地和山脉是于38Ma前在准平原基础上发育起来的;38～17Ma,研究区处于挤压凹陷状态,随着Ⅰ级夷平面解体而盆地范围扩大;17Ma以来,盆地南缘不断抬升,沉积中心向北迁移,于4.96～3.66Ma、0.93～0.84Ma和中更新世末—晚更新世初形成向北推进的Ⅱ级、Ⅲ级、Ⅳ级夷平面。盆山构造的运动方式有前展式、掀斜式和对冲式3种。前展式是盆山演化的主要方式且发生时代相对较早,后两者明显活动于0.93～0.84Ma,其中掀斜式运动是盆地内横向隆起形成的主要原因,而对冲式运动的标志是盆地北缘龙首山、合黎山的隆起。
Based on the basin-mountain structure and tectonic geomorphology, the author analyzes the tectonic and sedimentary records in the study area, and then discusses the coupling relationship between the Hexi Corridor and the Northern Qilian Mountains since the Cenozoic. The basins and mountains in the area were developed on the basis of quasi-plains before 38 Ma. The study area was in the state of squeezed depression for 38 ~ 17 Ma, and the basin expanded with the disintegration of level Ⅰ. Since 17 Ma, the southern margin of the basin has been continuously raised , The sedimentary center migrated to the north, forming Ⅱ, Ⅲ, Ⅳ level advancing northward from 4.96 to 3.66Ma, 0.93 to 0.84Ma and from the end of Mid-Pleistocene to late Pleistocene. There are three kinds of movement modes of basin-mountain structure, such as foreshortening, tilting and hedging. The foreshock is the main mode of basin-mountain evolution and occurs relatively earlier, and the latter two obviously move from 0.93 to 0.84Ma. The tilt-down movement is the main reason for the lateral uplift in the basin, and the sign of the hedge movement is the basin North margin of the first mountain, combined with the uplift of Mount Li.