High-resolution reconstruction of folding history in the central Syrian Arc fold system reveals episodic shortening

Abstract Intraplate shortening of the northern African passive margins has been widely observed, but the history of shortening and thus the underlying processes that led to their reactivation are still poorly understood. Situated at the northeastern African margin, the 1000-km-long Syrian Arc fold system preserves a classic example of such inversion that formed during the closure of the Tethys Ocean. Here, we present new structural and temporal constraints on the evolution of the Hatira monocline, which is situated at the central part of the arc. Our results suggest that intraplate folding was accommodated by a long-term slow background shortening acting since ca. 90 Ma, punctuated by one major folding pulse (ca. 79 Ma to ca. 77 Ma) and two additional relatively subdued pulses (ca. 67 Ma to ca. 65 Ma and ca. 57 Ma to ca. 54 Ma). This intraplate shortening might have been driven by the processes acting along the Africa-Eurasia subduction front (e.g., the secession of a double subduction zone) and/or the dynamic processes acting along the down-going subducting slab (e.g., slab buckling). Our results highlight the need for a new generation of high-temporal resolution plate kinematic models and detailed geodynamical numerical simulations that will link the observed intraplate deformation history with the processes acting along the confining plate boundaries.