The Transfer of Strike-Slip Partitioned Motion of Oblique Convergence Across the Zagros Fold-and-Thrust Belt

Authemayou, C.; Bellier, O.; Chardon, D.; Malekzade, Z.; Abassi, M.; Shabanian, E.

The Transfer of Strike-Slip Partitioned Motion of Oblique Convergence Across the Zagros Fold-and-Thrust Belt

Document Type : Seismology and Engineering Seismology

Authors

C. Authemayou ¹

O. Bellier ²

D. Chardon ¹

Z. Malekzade ³

M. Abassi ³

E. Shabanian ³

¹ Centre Européen de Recherche et d'Enseignement de Géosciences de l'Environnement (UMR CNRS 6635), Université Aix-Marseille 3

² Université Aix-Marseille III

³ IIEES

Abstract

Oblique plate convergence in collision zones may lead to complex regional strain partitioning because inherited crustal faults have various orientations with respect to the orogenic belt and the convergence vector. Combined field structural and geomorphic investigations and SPOT image analysis document the kinematic framework enhancing transfer of strike-slip partitioned right-lateral motion from along the backstop to the interior of the Zagros foldand-thrust belt in a context of active, high-angle right-oblique plate convergence. Transfer occurs by slip on the N-trending right-lateral Kazerun fault system that connects to the termination of the Main Recent Fault, a major NW-trending dextral fault partitioning oblique convergence at the rear of the belt. The Kazerun Fault system consists in three N-trending fault zones ended by bent, orogen-parallel splay thrust faults allowing slip from along the Main Recent Fault to become distributed by transfer to longitudinal thrust faults and folds.

Keywords

Zagros

Strike-slip Fault

Kazerun Fault System

Segmentation

Fault Kinematics