Structural and geomorphological constraints on active normal faulting and landscape evolution in Calabria, Italy

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Calabria is one of the fastest-uplifting and most seismically active regions in the Mediterranean, yet the time-averaged ( c. 10 6 years) rates of normal faulting remain poorly constrained. Here, we use digital elevation model analysis, geological cross-sections and a compilation of published data to quantify systematically along-strike the fault throws and time-averaged throw rates of the Serre, Cittanova, Armo, East Crati and West Crati faults. We show that regional uplift has uplifted both their hanging-wall and footwall blocks by c. 200–400 m, and the Aspromonte massif by up to c. 1150–1300 m. We find that these faults have throws between c. 640 and 1430 m, and throw rates between c. 0.6 and 1.4 mm a −1 . Their footwall ranges have variable proportions of inherited relief, up to c. 300–800 m. The channels draining these ranges reflect the active normal faulting and relief in their steepness indices, becoming c. 5–8 m 0.9 steeper for each 0.1 mm a −1 throw rate increment and each 100 m relief increase. Finally, the presence of knickpoints suggests that these channels are transiently responding to changes in relative base-level, which could be due to fault linkage or regional strain rate increases for the southern Calabrian faults, and to regional uplift acceleration in the case of the Crati faults. Supplementary material: Topographic profiles of the marine terraces and long profiles of rivers are available at https://doi.org/10.6084/m9.figshare.c.3689464