Slip Rate of Yema River–Daxue Mountain Fault since the Late Pleistocene and Its Implications on the Deformation of the Northeastern Margin of the Tibetan Plateau  

作　　者：LUO Hao HE Wengui YUAN Daoyang SHAO Yanxiu 

机构地区：[1]Key Laboratory of Active Tectonics and Volcano,Institute of Geology,China Earthquake Administration [2]Lanzhou Institute of Seismology,China Earthquake Administration [3]Lanzhou National Geophysical Observatory

出　　处：《Acta Geologica Sinica(English Edition)》2015年第2期561-574,共14页地质学报（英文版）

基　　金：the Special Fund for China Earthquake Research (Grant No.201408023);National Natural Science Foundation of China (Grant No.40872132,41030317);Chinese Academy of Sciences Key Project (XDB03020201)

摘　　要：The slip rate of Yema River-Daxue Mountain fault in the western segment of Qilian Mountains was determined by the dated offset of river risers or gullies. Results indicate that the left-lateral fault slip rate is 2.82± 0.20 mm/a at Dazangdele site, 2.00 ± 0.24 mm/a at Shibandun site, and 0.50± 0.36 and 2.80±0.33 mm/a at two sites in Zhazihu. The ideal average slip rate of the whole fault is 2.81 ± 0.32 mm/a. The lower slip rate confirms part of the displacement of Altyn Tagh fault was transformed into an uplifting of the strap mountains in the western segment of Qilian Mountains, whereas another part transformed into sinistral displacement of Haiyuan fault. This study illustrates that the slip of large strike-slip faults in the northeastern margin of the plateau transforms into crust thickening at the tip of the fault without large-scale propagation to the outer parts of the plateau.The slip rate of Yema River-Daxue Mountain fault in the western segment of Qilian Mountains was determined by the dated offset of river risers or gullies. Results indicate that the left-lateral fault slip rate is 2.82± 0.20 mm/a at Dazangdele site, 2.00 ± 0.24 mm/a at Shibandun site, and 0.50± 0.36 and 2.80±0.33 mm/a at two sites in Zhazihu. The ideal average slip rate of the whole fault is 2.81 ± 0.32 mm/a. The lower slip rate confirms part of the displacement of Altyn Tagh fault was transformed into an uplifting of the strap mountains in the western segment of Qilian Mountains, whereas another part transformed into sinistral displacement of Haiyuan fault. This study illustrates that the slip of large strike-slip faults in the northeastern margin of the plateau transforms into crust thickening at the tip of the fault without large-scale propagation to the outer parts of the plateau.

关 键 词：Slip rate strike-slip fault Yema River-Daxue Mountain fault Altyn Tagh fault Qilian ranges 

分 类 号：P542[天文地球—构造地质学]