Proceedings of the 12th International INQUA meeting on paleoseismology, active tectonic and archaeoseismology

336 PATA Days 2024 Slip rate across the SARF This study employed the folded 50-meters marine terrace (Tyrrhenian) along with the fault geometry to estimate a preliminary slip rate for the Late Pleistocene (Fig. 5) Field cross-sections along the southern segment reveal a continuous transition from Pliocene to Lower Quaternary deposits, with no significant unconformity. This suggests the initiation of SARF folding during the Quaternary period. Furthermore, observations across the three segments suggest non-synchronous folding onset activity with a northward progression of younger deformation. The northern younger segment, with minimal erosion affecting the fold, were used to assess cumulative late Quaternary activity. Fig. 4: An image depicting extrados normal faulting affecting recent red soil deposits (possibly Upper Holocene) on the SARF main anticline. Fig. 5: Topographic profile showing the uplift of the Tyrrhenian 50 m terrace above the SARF (Local. Fig. 1b) The folding onset is assumed to be 125 kyrs ago, corresponding to the age 50-meter marine terrace definitively involved in the folding (Fig. 5). The longitudinal topographic profile of this terrace directly reflects the fold geometry and can be considered a stratigraphic marker. This terrace is uplifted to 135 meters at the hinge of the SARF anticline (Fig. 5). Assuming a pure dip-slip along the fault. The total uplift of 85 meters has been taken as the vertical slip (VS) driven by the activity of the SARF. The calculation led to a net slip rate (SR) between 0.7 and 0.9 mm/yr for the last 125 kyrs. This result is consistent with the slip rates obtained along the El Asnam fault (M. Meghraoui et al., 1988).