Abstract:In this paper, inter-seismic creep velocity distribution is inversed, based on the InSAR-derived deformation field, using the SDM (steepest descent method) code. Then, the present-day strain state of the fault is discussed based on the inter-seismic creep velocity distribution and the local seismicity. The results show that, firstly, the mid-eastern segment of the Haiyuan fault zone is dominated by left lateral strike slip, and the maximum creep rates are 3.5 mm/a, 2.3 mm/a and 3.4 mm/a on depths of 18-24 km, 18-21 km and 15-21 km, respectively, from east to west direction. Secondly, the locking depth of the Maomaoshan fault is approximately 9 km, showing accumulating stress, and has the potential for strong earthquakes. Thirdly, the Laohushan fault shows aseismic slip in depth, showing less potential with strong earthquakes. Fourthly, the Haiyuan fault shows different movement characteristics on different segments. The eastern and western segments of the Haiyuan fault show obviously afterslip. However, the central segment of the Haiyuan fault shows slight afterslip reaching to 1.5 mm/a, and should be monitored in routine works.
SUN He,XU Jing,LIU Haoyuan . Depth Present-Day Movement in the Mid-Eastern Segment of the Haiyuan Fault Zone Based on InSAR[J]. jgg, 2017, 37(11): 1141-1145.