Revisiting Late Quaternary Slip-rate along the Maqu Segment of the Eastern Kunlun Fault, Northeast Tibet  

作　　者：LI Jian ZHANG Yueqiao LI Hailong XIONG Jinhong LI Jianhua WU Tairan 

机构地区：[1]Institute of Geomechanics, Chinese Academy of Geological Sciences [2]School of Earth and Space Sciences, Peking University [3]School of Earth Sciences and Engineering, Nanjing University

出　　处：《Acta Geologica Sinica(English Edition)》2016年第2期486-502,共17页地质学报（英文版）

基　　金：support of the Natural Science Foundation of China(41472178);the China Geological Survey projects(1212011120167,12120114002211)

摘　　要：The Late Quaternary slip rate along the Maqu segment of the eastern Kunlun Fault was estimated using a combination of high-resolution remote sensing imagery interpretation, field observations and differential Global Positioning System（GPS） measurements of offset river terraces, and 14 C dating of snail shells collected from offset risers. The results show that the left-slip rate along the segment is 3–5 mm/a, and that the vertical slip rate is 0.3–0.5 mm/a. Both the horizontal and vertical slips on the segment remain consistent over a distance of ~100 km. It means that no slip gradient as previously suggested occurred along the Maqu segment, and which thus might behave as an independent seismogenic fault. Judging from multiple relationships among young terrace offsets, we infer that co-seismic surface rupture produced by a characteristic earthquake with a magnitude of Ms7.0–7.5 on the Maqu fault could generate a horizontal slip of 4.5–5 m and a vertical slip of 0.45–0.5 m, with a corresponding ratio（Dh/Dv） of about 9. Two surface rupture events must have occurred over the past 3300 years, the latest one possibly between 1485 cal BP and 1730 cal BP.The Late Quaternary slip rate along the Maqu segment of the eastern Kunlun Fault was estimated using a combination of high-resolution remote sensing imagery interpretation, field observations and differential Global Positioning System（GPS） measurements of offset river terraces, and 14 C dating of snail shells collected from offset risers. The results show that the left-slip rate along the segment is 3–5 mm/a, and that the vertical slip rate is 0.3–0.5 mm/a. Both the horizontal and vertical slips on the segment remain consistent over a distance of ~100 km. It means that no slip gradient as previously suggested occurred along the Maqu segment, and which thus might behave as an independent seismogenic fault. Judging from multiple relationships among young terrace offsets, we infer that co-seismic surface rupture produced by a characteristic earthquake with a magnitude of Ms7.0–7.5 on the Maqu fault could generate a horizontal slip of 4.5–5 m and a vertical slip of 0.45–0.5 m, with a corresponding ratio（Dh/Dv） of about 9. Two surface rupture events must have occurred over the past 3300 years, the latest one possibly between 1485 cal BP and 1730 cal BP.

关 键 词：eastern Kunlun fault Maqu fault Late Quaternary slip-rate offset terraces paleo-seismicity 

分 类 号：P315.2[天文地球—地震学] P534.63[天文地球—固体地球物理学]