Long-term behaviour of the late Quaternary normal faults in the Straits of Messina area (Calabrian arc): structural and morphological constraints

The Calabrian arc is located in the peri-Tyrrhenian orogenic belt of southern Italy and is characterised by intense post-collision dynamics. This consists of rapid regional uplifting combined with active normal faulting affecting the Tyrrhenian side of Calabria and the Ionian coast of Sicily (the Siculo-Calabrian rift zone). The effects of the two combined processes are well exposed in the Straits of Messina area that represent a major transfer zone located between two opposing sets of normal faults characterising the southern Calabria and the northeastern Sicily branches of the rift. In the Straits of Messina region, the distribution and elevation of the upper Quaternary marine terraces suggest a southward propagation of the normal fault belt, from Calabria to Sicily. It occurred at about 125 ka, after a long period of tectonic quiescence and was triggered by huge elastic releases in southern Calabria. The longterm behaviour recorded on the distinct fault segments of the rift is to relate to the presence of a crustal barrier that influenced both the geometry and the fault propagation along the rift zone. (C) 2002 Elsevier Science Ltd and INQUA. All rights reserved.