Early Pleistocene to late Holocene activity of the Magnola fault (Fucino fault system, central Italy)

The Magnola Mounts (the Abruzzi, central Italy) are bound towards the Fucino Plain by a steep fault slope that is marked at its base by a continuous rock fault scarp (a "nastro", in Italian). In the Apennines, this particular feature is often interpreted a priori as evidence of Holocene tectonic activity, although sometimes climate-related exhumation processes or gravity-driven phenomena can generate such geomorphic markers. To unravel this possibility, we searched for field geological indications, and here report on our findings of both long-term and short-term evidence concerning the activity of the Quaternary Magnola fault. Paleoseismological analysis carried out across the talus resting against the rock fault plane revealed evidence of repeated surface rupture events from, and during, the Holocene, to historic times. Following a comparison of the ages of these events with those already known for the Fucino Basin faults, we argue that the Magnola fault acts as the north-western-most strand of the Fucino fault system, which is, in turn, the structure that was responsible for the devastating 1915, M_W 7, earthquake, as for other earthquakes in the past.