东北地区近期水平形变应变场研究

根据2011年和2013年东北地区GPS观测资料计算得到的地壳水平运动场和连续主应变场，研究了东北地区地壳运动特征和应变应力状态， 求解块体运动参数，计算东北主要断裂带的错动速率和断层应变应力状态，分析断裂带活动性。研究表明，2011～2013年期间，东北地区东部运动规律性相对较好，且东部运动场收敛于珲春-龙井一带，向东位移；中部和西部运动场一致性较弱，位移方向相对分散。主应变反映出，东北地区2011～2013年主压应力轴优势方向为NE55°。两个水平主应变轴都缩短的挤压区分布面积较小，两个主应变轴都伸长的拉张区次之，最小主应变轴缩短的区域和最大主应变轴伸长的区域所占比重最大。该时段Ms≥5.0地震集中在2013年，地震多发生在运动方向转折带附近及挤压-剪切活动区，最大的5.8级地震发生在不同运动区交界带和挤压作用相对强烈的构造带。

Research of the Recent Deformation\|strain Field in Northeast China

Based on the horizontal movement field and continuous principal strain field calculated from the GPS data of 2011 and 2013 in Northeast China, the crustal movement and strain\|stress state in Northeast China are researched. The offset rates of major fault zones in Northeast China and fault strain\|stress state are calculated by computation of the block motion parameters, and then the fault zone activities are researched. The results suggest that during the period of 2011-2013, the regularity of the East movement field of Northeast China is relatively good, and the East movement field converges along Hunchun\|Longjing zone with Eastward displacements. The consistency of the central and West movement field of Northeast China is relatively weak, and the displacement directions are relatively scattered. The main strain results reflect that the direction of the principal compressive strain axis of Northeast China during 2011-2013 is NE55°. The distribution area of the compressive region with both horizontal principal strain axes shortened is smallest, and the extension region with both principal strain axes stretched is the second smallest, and the region with the minimum principal strain axis shortened and the maximum principal strain axis stretched (shear activity area) is the largest proportion. Ms≥5.0 earthquakes during this period are concentrated in 2013, and most of the earthquakes occurred on the surrounding zone of movement direction transition and compressive\|shear area, and the biggest Ms 5.8 earthquake occurred on the transitional zone of different movement fields and tectonic belt with relatively strong compression action.