Far-field Coseismic Surface Displacement Caused by the Mw9.0 Tohoku Earthquake

Based on 3-day IGS and CGPS observations before and after the great Mw9.0 Tohoku earthquake,we presented the coseismic deformation field composed of 77 sites for China and surrounding area.The results show that significant displacements is detected in a wide area ranging from the Korean peninsula to the north and northeast of China.Almost all sites move forward to the epicenter.The horizontal displacement is up to 1-3 cm in the northeast of China,3-8 mm in the north China,and 2 cm in the Korean peninsula.The vertical coseismic offsets of CGPS stations in China are uplift,but the magnitudes are very small.The up-down alternate phenomenon of far and near field coseismic vertical displacement reflects its undulating characteristics.In consideration of the earthquake relevance in the identical tectonic system,we should pay close attention to the activities of the Tan-lu fault belts which across the region of eastern China with the advantages provided by the intensive cover of CGPS.