Paleostress Analysis in the shirshotor area (one of Northern Branches of Nehbandan fault)

Authors

1 Department of Geology, University of Birjand, Birjand, Iran

2 Department of Geology, Birjand University, Birjand, Iran

Abstract

The study area is located in the Sistan suture zone. The purpose of this study is to investigate of the variation maximum stress (σ1) along the history of the tectonic regime with the use of structural markers, including faults, foliated structure and veins in the study area. In order to investigate paleostress variations, have been used stress analysis methods on the fault data extracted from faults with using the relevant software. The results indicate has two stress trends during tectonic history based on the age of rock units. The initial direction of the stress is NW - SE that is acted since Cretaceous to the before Eocene, after that the direction of stress has been change toward NE- SW since Eocene to the present time, which is corresponding to current regime. Furthermore by combining the results obtained from stress analysis with the results obtained from the kinematic of veins and foliation show the variations of directional stress field is clock rotation.

Keywords


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