Earthquake Transients and Mechanics of Active Deformation: Case Studies from Pakistan and Italy.

The understanding of the dynamics of the lithosphere and dominant physical processes during the earthquake cycle is important to estimate the seismic hazard of a given region. In the present study, we rely on seismology to image the geometry of both lithosphere and seismogenic faults and on geodesy to quantify the surface deformation and then we model the time-dependent dynamics of the coupled lithosphere-fault system. In the first part of the work, we study two earthquake transients, in which, one lasts for a few years following the 2005 Mw 7.6 Kashmir’s earthquake and the second exhibits deformation for a couple of weeks before the 2009 Mw 6.3 L’ Aquila earthquake in the central Apennines, and model the long term inter-seismic deformation across the Idrija fault in the Dinarides (Western Slovenia). In this part of work, we report on the dominant physical process during different phases of the earthquake cycle, namely the postseismic and preseismic phases. In the second part of the work, we investigate the temporal change of stress state over the Dinarides and Eastern Alps through the coseismic stress changes induced by earthquakes in this region, together with the related post-seismic and interseismic changes due to relaxation processes and interseismic loading. In the last part of the work, we study the dynamics of a dense lithosphere over a weak asthenosphere beneath the Adria plate and model the present day crustal deformation in the peri-Adriatic region including the Apennines, the Alps, and the Dinarides. The implications of these investigations stand in the understanding of how deformation at the plate boundary scale is transferred to active faults accounting also for transients in the system.

The understanding of the dynamics of the lithosphere and dominant physical processes during the earthquake cycle is important to estimate the seismic hazard of a given region. In the present study, we rely on seismology to image the geometry of both lithosphere and seismogenic faults and on geodesy to quantify the surface deformation and then we model the time-dependent dynamics of the coupled lithosphere-fault system. In the first part of the work, we study two earthquake transients, in which, one lasts for a few years following the 2005 Mw 7.6 Kashmir’s earthquake and the second exhibits deformation for a couple of weeks before the 2009 Mw 6.3 L’ Aquila earthquake in the central Apennines, and model the long term inter-seismic deformation across the Idrija fault in the Dinarides (Western Slovenia). In this part of work, we report on the dominant physical process during different phases of the earthquake cycle, namely the postseismic and preseismic phases. In the second part of the work, we investigate the temporal change of stress state over the Dinarides and Eastern Alps through the coseismic stress changes induced by earthquakes in this region, together with the related post-seismic and interseismic changes due to relaxation processes and interseismic loading. In the last part of the work, we study the dynamics of a dense lithosphere over a weak asthenosphere beneath the Adria plate and model the present day crustal deformation in the peri-Adriatic region including the Apennines, the Alps and the Dinarides. The implications of these investigations stand in the understanding of how deformation at the plate boundary scale is transferred to active faults accounting also for transients in the system.