摘要
Combined deformation of sediments and regional information, it can be deduced that an existed thrust, Qaibeiyuan-Qinghai Nanshan northwest dipping thrust was reactivated along the region of the southward range-front of modern Qinghai Nanshan by Late Cenozoic right-lateral movement of Wenquan fault. The mountains range is thus a tectonic ramp that thrusted southward over the hemas-microsoft-com:office:smarttags" />Gonghe Basin. The movement of Qinghai Nanshan changed the geomorphology of the basin and the sediments in the southward range-front were tilted to southwest. After the unconformity, the Qinghai Nanshan has served as a watershed boundary and then became a new provenance of the Lake Qinghai and Gonghe Basin.