Paleostress Analysis in the Shahabad Wedge Shaped Shear Zone- E Iran, to Comparison the Patterns of Deformation in Quaternary and Recent


Department of Geology, University of Birjand, Iran


The Shahabad shear zone is situated in the north east of Birjand, that is a wedge shaped shear zone. Comparison arrangement of stress axes in the Quaternary from using analysis of fault slip and young structures was demonstrated quaternary structures as Shahabad anticline, Marak anticline. The Mohammed Soltan tension fractures and deformation bands it could be useful in the local stress determination due to the minimal number of phases which effect on the young structures. The stress patterns are varied in different parts of the Shahabad shear zone because of the wedge shape of this zone. The regional tectonic stress due to the Central Iran-Afghanestan plates N-NE convergence is a main stress and in the quaternary and the present unchanged also the effect of deformation of that convergence obvious as locally with the formation of Shahabad seismic folds and slip along the Kuch and Shahabad right lateral faults.


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