Geomorphological and Morphometric Analyses of the Catanzaro Trough (Central Calabrian Arc, Southern Italy): Seismotectonic Implications

Abstract

In this work, we investigated the landscape response to the recent activity of the faults affecting the Catanzaro Trough, a seismically active structural basin that developed transversally to the Calabrian Arc (Southern Italy) during the Neogene-Quaternary. We carried out a geomorphological and morphometric study of the drainage networks and basins intercepted by the Quaternary faults that were previously mapped through remote and field analyses. The study confirms the occurrence north of the Catanzaro Trough of a WNW-ESE-oriented left-lateral strike-slip fault system (here named the South Sila Piccola Fault System), which accommodates the differential SE-ward migration of the upper crustal sectors of the Calabrian Arc, and of a south-dipping WNW-ESE-oriented oblique fault system (the Lamezia-Catanzaro Fault System), characterized by a predominant normal component of movement. The latter delimits the Catanzaro Trough and accommodates the transition from a strike-slip regime to an extensional regime in the south. Inside the Catanzaro Trough, we detected for the first time a NNE-SSW-trending, WNW-dipping fault system (here named the Caraffa Fault System). This system contributes to accommodate the extension that occurs orthogonally to the southern sector of the Calabrian Arc. The geomorphological and morphometric analysis revealed the recent activity of these fault systems. In particular, the activity of the Caraffa Fault System is evidenced by the differential uplift and tilting of discrete areas inside the basin. Given its location, geometry, and kinematics, the Caraffa Fault System could be responsible for the occurrence of large historical earthquakes.