Document Type : Original Research Paper

Authors

1 Payam-e-Nour university of Sari, Sari, Iran

2 International Institute of Earthquake Engineering and Seismology, Tehran, Iran.

3 Paul Cezanne University, France

Abstract

      The present study covers the area between 500E to 510, 30`E of the Zagros Fold-and-Thrust Belt. The deformation pattern of west High Zagros Belt (HZB) has been considered to reflect a complete strain partitioning due to the Arabian oblique plate convergence and Central Iran. In this context the NW-SE trending Main Recent Fault (MRF) acts as rear boundary of the belt, kinematically taking up the strike-parallel component of oblique plate motion of Arabia, whereas the High Zagros Fault (HZF) with the same fault trend as MRF accommodates the orogen-normal shortening due to this movement. Using fault-slip inversion on fault planes mostly affecting the Bakhtiary conglomerate (Plio-Pleistocene in age) along the HZB, the deviatoric stress tensor and its shape factor (R) calculated at 29 stations. The geomorphic evidences and the fault kinematics show that the major parts of the HZF are consistent with strike-slip kinematics. This implies that the HZF also accommodates some part of strike-parallel component of oblique convergence collision.

Keywords

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