Morphotectonic processes and their outcomes at the Northern Apennine front in the Oltrepo Pavese area (Sheet 160 - Pavia CARG Project, South-western Lombardy, Italy)

The investigation of the landscape evolution of the transition zone between outcropping thrust-fold belts and their buried outermost fronts can be challenging to unravel, due to difficulties in homogenizing and correlating field and subsurface data. An attempt to clarify this complex relationship is being pursued in the central-western sector of Emilian Arc in the Northern Apennine (Italy), benefiting from the activities for the implementation of the “Foglio 160Pavia”, as part of the Italian CARG Project of geological mapping. The main purpose of this work is the comprehensive reconstruction of the landscape evolution, with particular emphasis on assessing the role of Plio-Pleistocene tectonic activity in shaping landforms, both in the outcropping sector of Northern Apennines front and in the buried outermost ones. The study area, located in the south-western Lombardy region (Oltrepo Pavese), features the units exposed in the Northern Apennines outcropping chain, which rapidly slopes below Quaternary deposits of the Po Plain covering the front of the belt and its foreland. The hill sector of the area includes a Paleocene to Pleistocene sedimentary succession, involved in the SW-NE oriented tectonic vergence of the Apennines tectonic units. A detailed 1:10.000 scaled original map of the hillslopes and a 3D model of the regional stratigraphic and tectonic surfaces of the sector of Po Plain facing the Northern Apennine margin are already available for the study area. Within this framework, we apply morphometric analysis to evaluate the influence of the tectonic structures of the Northern Apennine front, both outcropping in the hill sector and buried under the Po Plain deposits, and to understand the role of surface processes on the geomorphological evolution of this area. The combination between morphometric results and stratigraphic, structural, and geomorphological markers observed and collected from fieldwork or derived from a 3D subsurface model of the regional scale structures, provides valuable insights for interpreting the landscape evolution of this sector of the Northern Apennines and possible evidences of recent/ongoing tectonic activity.