Morphotectonic evolution of eastern Sardinia: relations between inland and the continental margin

The tectonic structure of Sardinia is linked to the geodynamic evolution of the western Mediterranean during the Alpine phase. In particular, the eastern continental margin is the result of the opening of the Tyrrhenian basin which is still evolving. The Pliocenic and Quaternary distensive phase lead an uplift in Sardinia whose effects are manifested in the geomorphological setting. Morphotectonic analysis were used to characterize paleo and active geomorphological processes in Ogliastra area. Palaeo-erosive surfaces, volcanic mesas, Steep slopes, involute hydrographic basins, widespread landslides shaped the inland, while the submerged continental margin in affected by engraved active canyons and landslide.

To analyze the continental area large scale geological, geomorphological, geostructural, morphostratigraphic surveys integrated by PS-INSAR, Uncrewed aerial vehicle, LiDAR Remote sensing data were used.

Seismic sparker, sub-bottom profiler chirp, multibeam, side scan sonar made it possible to analyze the evolution of the submerged area.

In particular, fluvial captures, river terraces, engraved valleys, waterfalls and heterogeneous water drainage characterize the streams setting. Coastal Quaternary volcanism present relief inversion plateaus. The slope area affected by different kind of landslide conferring at the Ogliastra the main geomorphogical hazard of Sardinia. Widespread Deep seated gravitational slope deformation both active and quiescent are preset in different structural and tectonic setting. Paleo erosive surface since the Carboniferous are found located at different elevation.

The eastern continental margin of Sardinia is made up of a north-south oriented host and grabben system linked to the open Tyrrhenian basin. The continental shelf is very narrow and indented by several narrows and straight submarine canyons. Head retreat processes of the canyons are evident, that have notably affected the continental shelf. The continental slope is made up of intraslope basins and seamounts oriented N-S whose slopes are affected by active and paleo landslides, slumps and erosional incisions.

Multi-source and multi-scale data showed the role of the uplift rebound in the landscape evolution.

High resolution morphotectonic map were reconstructed, highlighted and integrated all different morphologies and process.