Document Type : Original Research Paper
1 M.Sc., Department of Geology, TarbiatModares University, Tehran, Iran
2 Professor, Department of Geology, TarbiatModares University, Tehran, Iran
3 Associate Professor, School of Geology, Tehran University, Tehran, Iran
In this paper, the structural evolution of Bamu fault zone located in the Zagros folded belt zone is presented as an example of northeast-trending fault zone in the Zagros, using the kinematic and dynamic analysis of accompanied structures. Based on structural and paleostress analyzes two phases of shortening were determined as NE and NNE. In order to define the chronology of the deformation stages in the region, the relationship between fault structures and folds in the folded rock formations has been utilized. The result showed that the first compression stress trend in the area was NE that caused formation of the Bamu transverse Fault with left-lateral strike-slip mechanism and its accompanied structures. Since this stage of deformation has affected the Oligocene- early Miocene formations, more likely occurred at this time. During the next phase the shortening direction, due to change in the collision zone direction of the Arabian-central Iran in the Miocene-Pliocene, has changed to NNE which causes development of younger structures in the form of folding and reverse faulting in the fault zone. This shows that the NE-trending fault zones, like other major NW-faults, in Zagros affected by the change in the convergence of Zagros collision.