Abstract:Based on GPS ground-to-earth observation velocity field data of the continental tectonic environment monitoring network of China mainland in the Bohai rim region from 2009 to 2014, we use the global rotation and linear strain models for calculation. The area is divided into five sub-blocks, and we obtain the strain field of 0.5°×0.5° of the research area relative to the Eurasian plate. The spatial variation of the deformation velocity field and the strain field are analyzed. It is found that the Bohai rim region presents a two-way trend expansion movement of 0.25×10-9/a NW-SE 111.3°. The strain details of each sub-block are provided: the Taihang block is NW-SE 116.3°, and the Shanxi block is the weak expansion movement of NW-SE 130°. The weak compression movement is NW-SE 144.3°, NE-SW 39.5° and NW-SE 155.6° in the Jiaoliao, Jilu, and Yinshan-Yanshan blocks respectively. The magnitude of the expansion motion of the Taihang block is larger than that of the other secondary blocks. Although the deformation of each sub-block in the Bohai rim region is spatially different, the direction of the main compressive strain axis of the Bohai rim region is basically NEE-SWW, the strain axis is basically NNW-SSE, and the main compressive strain axis direction is NE 47.70°~8974°, which is generally consistent with the dominant direction of the principal compressive strain axis of the region obtained by geophysical methods, indicating that the current crustal movement in the Bohai sea region is relatively stable.
ZHAO Xukun,ZHANG Jun,LEI Qiankun et al. Analysis of the Current Tectonic Movement Deformation Characteristics in the Bohai Rim Region and Adjacent Areas[J]. jgg, 2019, 39(11): 1101-1105.