Horizontal surface velocity and strain patterns near thrust and normal faults during the earthquake cycle: The importance of viscoelastic relaxation in the lower crust and implications for interpreting geodetic data

摘要: In recent years, more and space-geodetic data on the surface deformation associated with earthquakes intracontinental normal thrust faults have become available. However, numerical models investigating coseismic postseismic near such in a general way, i.e., not focused particular earthquake, are still sparse. Here we use three-dimensional finite element that account for gravity, far-field (“regional”) extension/shortening relaxation viscoelastic lower crust to quantify caused by an Mw ~7 earthquake dip-slip fault. The is characterized horizontal shortening footwall of fault extension hanging wall fault—consistent elastic dislocation models, geological field observations, GPS from Italy Taiwan. During phase, domains extensional contractional strain exist next each other both types. spatiotemporal evolution these as well velocities rates strongly depend viscosity crust. For viscosities 1018–1020 Pa s, signal detectible 20–50 years after earthquake. If containing used derive regional rates, stations may show too high or low even apparently wrong tectonic regime. By quantifying through space time, our help interpret identify most suitable locations stations.