Effect of coseismic and postseismic deformation on homogeneous and layered half-space and spherical analysis: Model simulation of the 2006 Java, Indonesia, tsunami earthquake

Abstract

Abstract We simulate surface displacements calculated on homogeneous and layered half-space and spherical models as applied to the coseismic and postseismic (afterslip and viscoelastic relaxation) of the 2006 Java tsunami earthquake. Our analysis of coseismic and afterslip deformation suggests that the homogeneous half-space model generates a much broader displacement effect than the layered half-space and spherical models. Also, though the result for surface displacements is similar for the layered half-space and spherical models, noticeable displacements still occurred on top of the coseismic fault patches. Our displacement result in afterslip modeling suggests that significant displacements occurred on top of the main afterslip fault patches, differing from the viscoelastic relaxation model, which has displacements in the front region of coseismic fault patches. We propose this characteristic as one of the important features differentiating a postseismic deformation signal from afterslip and viscoelastic relaxation detected by geodetic data.