Rift and supradetachment basins during extension: insight from the Tyrrhenian rift

The style of extensional basins provides key insights into the magnitude of extension and their kinematic evolution. The newly documented Stilo rift (off Calabria, Italy) features a Serravallian–Tortonian rift basin bounded by a high-angle normal fault and a Messinian adjacent supradetachment basin bounded by a low-angle normal fault. We propose a kinematic model suggesting the abandonment of the high-angle normal fault and the beginning of low-angle normal fault activity, followed by a rapid increase in extension. The triggering mechanism of the low-angle normal faults can be attributed to rapid rollback of the subducting plate and/or to isostatic crustal uplift. Supplementary material: The seismic dataset and methods of interpretation are available at http://www.geolsoc.org.uk/SUP18794.