Geodynamic constraints of the peri-Tyrrhenian orogen (Tyrrhenian Sea-Apennines) from lineament swarm analysis

""\\"Regional geodynamics is responsible of a series of effects. that notably include tectonics and seismicity. They in turn control. the morphology of the surface of the planet. The regional. dimension of the peri-Tyrrhenian orogen reveals that its. evolution is deeply involved in a lithospheric scale dynamics. As. a result, we expect different observable and\\\\\\\/or measurable effects. at the various scales from the outcrop evidences to the subcontinental. deformation corridors. Effects at the various scales. not necessarily are directly related, and their relations should be. carefully understood taking into account both their geometry and. spatial distribution. A classical example is represented by an en. echelon system. Each single fracture is the effect of a local. extension, yet their spatial distribution shows that these local. stresses are the effect of a larger scale shear zone with a different. orientation.. Remotely sensed images proved the existence on the Earth. surface of linear features with dimensions spanning over three. order of magnitude: from hundreds of meters to thousand of. kilometers. Such features are referred to image lineaments and. are generally related to alignment of morphological features in. continental environment such as onshore crests, ridges, valleys. and troughs. In the oceans lineaments relate to the scars. associated to the seafloor spreading and fracture zones. Synthetic. scale images of tectonically active regions revealed the existence. of groups of regional scale lineaments on the earth surface. appearing as image textural anisotropies. They clusters around. preferential orientations to form lineament domains. These. domains occupies well defined areas to form lineament swarms.. Lineament domain analysis on regional scale images of the. Earth surface proved a useful tool to investigate regions. characterized by active tectonics (Wise et al., 1985; Funiciello et. al., 1977; Cianfarra & Salvini, 2008).. Both the Tyrrhenian Sea and the Apennines are geodynamic. blocks within the collisional puzzle between Africa and Europe. in the Central Mediterranean area.. In this work we explore the possible relations between these. two blocks by lineaments analysis. The found lineament domains. were interpreted as reflecting the structural grain of these two. geodynamic regions. Lineament detection was done by using. original automatic methods. Domains were identified by. statistical analysis. This work analyses lineaments detectable by. simulating different directions of lighting condition on the. DEMs. This allowed to properly evaluate the influence of the. light condition changes in the lineaments produced by. morphological features. The comparison among the analyses. showed that the different lighting conditions induce rotations of. few degrees of the mean azimuth of each lineament domain. This. rotation relate to the result of two contrasting effects: tectonics,. that tends to enhance linear morphologies, and erosion that. progressively smoothes them. Lineament domains characterised. by small rotations relate to morphologies where the tectonic. processes prevail on the erosional ones. Lineament domains. therefore have rotations inversely proportional to their tectonic. activity.\\"""