Present vertical movements in Central and Northern Italy from GPS data: Possible role of natural and anthropogenic causes

• GPS observation is used to determine the present vertical kinematics in the Central and Northern Italian peninsula.
• A comparison between the present GPS vertical field and the long-term vertical motion estimated from geophysical and geological observation.
• Discussion on how the GPS vertical velocity field may be related with tectonic processes, ground settlement and anthropic activities.

Insights into the present vertical kinematic pattern in Central and Northern Italy are gained by the analysis of GPS data acquired by a network of 262 permanent stations, working over various time intervals since 2001. Uplift is observed in the Alps (up to 5 mm/yr) and Apennines (1–2 mm/yr), whereas subsidence is recognized in the southern Venetian Plain (2–4 mm/yr) and the eastern Po Valley, where the highest rates are observed (up to 9 mm/yr between Reggio Emilia and Rimini). On the other hand, the western part of the Po Valley presents very low vertical rates. The boundary between subsiding and not subsiding Po Valley nearly corresponds to the Giudicarie tectonic discontinuity. It is argued that the different kinematic patterns of the eastern and western Padanian sectors may also be related to the underthrusting of the eastern domain beneath the western one. Some considerations are then reported on how the various causes of vertical movements (tectonic and sedimentological processes) may contribute to the observed kinematics.