Apennines subduction-related subsidence of Venice (Italy)

The foreland regional monocline related to the northern Apennines subduction can be followed from the Po Basin to the Friuli region, Italy, at least 240 km north-eastward. In seismic reflection profiles of the Po Basin and of the northern Adriatic Sea, the dip of the regional monocline gradually decreases from about 22° to close to 0°. Pleistocene sediments onlap and pinchout to the northeast. Venice is located on a segment of the active monocline dipping about 1.8° to the southwest. In sediments around the Venice area, the 1.43 Ma limit is in the 960–1500 m depth range, indicating a long term subsidence rate of about 0.7 –1.0 mm/yr. Therefore a significant part of the natural component of the town subsidence is related to the north-eastward retreat of the Adriatic subduction. The subduction related downflexure affects the whole of the Po Plain basin and part of the Southern Alps, where it opposes to the general uplift related to orogenesis.