Numerical simulation of Holocene depositional wedge in the southern Po Plain-northern Adriatic Sea (Italy)

摘要

In the last 10 kyr BP, a coastal depositional wedge formed along the southern Po Plain margin. Shoreline regression accelerated abruptly in the Iron Age, and especially in the last 2 kyr, due to the increased woodland removal on the Apennines. The deposition of the Holocene sedimentary wedge is simulated here, along four coast-tranversal transects, using a finite-element two-dimension mathematical model. The model was constrained using the present topographic surface, the maximum flooding line of the Holocene transgression, architecture and texture of depositional wedge, the location of coastlines, aeolian dunes and ancient offshore delta-sand. The sediment volume required to calibrate the simulations along the sections ranges from about 165,000-870,000 m~3 m~(-1); the maximum tectonic subsidence varies from 0.1 to 0.7mm yr~(-1). The minimum sand amount required by the model to stop the accelerated erosion of the Cervia beach is about five times the one employed in recent (April 2002) recovery works.