Apatite fission track dating data of 9 samples selected from Pulu range in the northern regions of west Kunlun mountain were obtained. The results recorded that rapid uplift occurred in 8-9Ma B.P. in this region. The FT ages range from 20Ma to 4.5Ma
so we infer that the deposited age (3.5-1.6Ma) of Xiyu conglomerate is uncertainly corresponding to the time of rapid uplift of west Kunlun moutain.