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Cenozoic sediments in the foreland basin——Jiuquan Basin in west Hexi Corridor recorded tectonic uplift information of the Qilian Mountains. High resolution paleomagnetic dating of the Laojunmiao (LJM) section across the central LJM anticline in the southern Jiuquan Basin reveals ages of the Getanggou Member, Niugetao Member in the Shulehe Formation, the Yumen Conglomerate, Jiuquan Conglomerate and Gobi Formation at >13―8.3 Ma, 8.3―4.9 Ma, 3.66― 0.93 Ma, 0.84―0.14 Ma and 0.14―0 Ma, respectively. Sedimentary evolution study suggests that the Qilian Mountains should begin to rise gradually since ~8―6.6 Ma, accompanied by sedimentary environments changing from lacustrine mudstones-sandstones to alluvial conglom- erates. Rapid uplift of the Qilian Mountains began at ~3.66 Ma, followed by a series of stepwise or intermittent intensive uplifts at about <1.8―1.23 Ma, 0.93―0.84 Ma and 0.14 Ma, which finally resulted in the present high Qilian Mountains.
Cenozoic sediments in the foreland basin - Jiuquan Basin in west Hexi Corridor recorded tectonic uplift information of the Qilian Mountains. High resolution paleomagnetic dating of the Laojunmiao (LJM) section across the central LJM anticline in the southern Jiuquan Basin showing ages of the Getanggou Member , Niugetao Member in the Shulehe Formation, the Yumen Conglomerate, Jiuquan Conglomerate and Gobi Formation at> 13-8.3 Ma, 8.3-4.9 Ma, 3.66-0.93 Ma, 0.84-0.14 Ma and 0.14-0 Ma, respectively. Sedimentary evolution study suggests that the Qilian Mountains should begin to rise since ~ 8-6.6 Ma, accompanied by sedimentary environments changing from lacustrine mudstones-sandstones to alluvial conglom- erates. Rapid uplift of the Qilian Mountains began at ~ 3.66 Ma, followed by a series of stepwise or intermittent intensive uplifts at about <1.8-1.23 Ma, 0.93-0.84 Ma and 0.14 Ma, which finally resulted in the present high Qilian Mountains.