Determining long-term slip rates in the Northern Zagros Fold-and-Thrust Belt (Kurdistan Region of Iraq) from tectonic geomorphology, structural modeling and OSL-dating

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The Kurdistan Region of Iraq (KRI) hosts the northwestern segment of the Zagros Mountains fold-and-thrust belt, which formed from the convergence between the Eurasian and Arabian plates. GPS-data suggest current convergence velocities of c. 16 to 22 mm a-1 between these two plates, of which c. 10 mm a-1 are consumed in the Zagros Mountains alone. The Zagros Mountains in the KRI are by far the least investigated segment of the entire Zagros fold-and-thrust belt, yet they host numerous vestiges of tectonically induced landscape changes throughout the Quaternary, such as successive wind gaps and sets of river terraces affected by surface uplift around fault-related folds. The target area for our investigations is the Greater Zab River and its tributaries, which traverse the NW Zagros fold-thrust belt between the Main Zagros Thrust and its frontal foothills. We intend to constrain the rates of surface uplift along several fault-related structures by analyzing their geomorphological evolution and by dating uplifted depositional terraces with the optically stimulated luminescence method (OSL). In combination with geometrical models of the fault-related folds, we will convert surface uplift rates into horizontal fault-slip rates. This approach will yield long-term convergence rates that average across timescales of 10 to 100 kyr.