Flexural behavior of the continental lithosphere in Italy - Constraints imposed by gravity and deflection data

This paper presents a simple model that describes the geometry of subducted continental lithosphere as the result of flexural loading of a thin elastic sheet. The method involves a procedure for systematically matching the plate flexure and gravity data to the best-fitting two-dimensional flexural geometry obtained by a thin elastic sheet of specified elastic strength. It is shown that the model can explain both the deflection of the lithosphere and the gravity anomalies observed along four profiles across the Apennine convergent system in Italy. The results of calculations suggest that in subduction systems, like the Apennines, that are characterized by backarc extension, forces acting on subducted lithosphere at depth can be expressed at the surface in the geometry of the foredeep basin that forms adjacent to the subduction zone.