Separating natural and anthropogenic vertical movements in fast subsiding areas: the Po plain (N. Italy) case

The geological and the anthropogenic components of vertical movement act on different time scales (millions to thousands years and hundreds to tens of years respectively). This peculiarity has been used in order to separate t he factors controlling sea-level changes in the Po plain area. The componen t due to long term geological processes is calculated from stratigraphic da ta (commercial wells and seismic lines). Adding to this long term component the contribution of Pleistocene deglaciation obtained from analytical mode ls, an estimate of the total natural component of vertical velocities is ob tained. The validity of these values is confirmed by comparison with veloci ties obtained from archaeological data and detailed palynological and paleo ntological analyses. The anthropogenic components can be inferred by compar ison between the total natural vertical velocities we calculate and vertica l velocities obtained from other data sets. Two applications are proposed u sing tide gauge records and geodetic data respectively.