Modern movement and deformation in the South China Sea shown by GPS measurements and numerical simulation

摘要

To better understand the crustal deformation of the South China Sea Basin,we produce a mechanically consistent 2-dimensional model for observing regional velocity field in the South China Sea (SCS).We studied the dominating regional tectonic stress field by geodetic measurements and finite element analysis,the spatial variations of velocity field and strain field,and relative movements among different blocks,using a 2-dimensional model describing crustal deformation of the South China Sea Basin.Strain results show that the SCS is extending at present.The western part of SCS is opening gradually in NW-SE direction from its northern margin to the south,but the eastern part of SCS is opening gradually from its central part to the north and south.In addition,we analyzed the plate kinematics to the deformation of the SCS,using a two-dimensional finite element model.Our simulations results are well explained by available geodetic data.The movement of SCS is resulted from interactions among Indian Plate,Pacific Plate,Philippine Sea Plate,and Eurasian Plate.