Structural evidences and shear sense indicators at Qerkh Yashar region, northwest of Khoy

Authors

1 Geology Department, Faculty of Sciences, Urmia University

2 Associate Professor Tectonics, Department of Geology, Khoy Branch, Islamic Azad University, Khoy, Iran

Abstract

The Qerkh Yashar region in the northwestern Khoy is placed 140km away from Urmia. One of the distinctive features of this area is its setting in the brittle-ductile shear zone. Existence of faults, folds, veins and boudinage and also mylonitic rocks at the study area, illustrate on its location at brittle-ductile zone. On the other hand, the presence of different types of mylonitic rocks in the research area, which have various structural fabrics, indicate its setting in the brittle-ductile zone. In this research, within the sampling of field works, microscopic structures have also been used to determine the shear direction. The trend of structures is NW-SE and contains: C, S, and C' fabrics, mica fish structure, disharmonic folds, mantled porphyroclasts of δ-σ type and folded boudinage as shear sense indicators that exhibit the right lateral slip at the deformed area. The trend of the structures in the studied area is NW-SE and the kinematic indicators include: (C, S, C`) type fabrics, mica structures, asymmetric folds, mantled porphyroclasts of the type (𝜹, 𝝈) and folded boudinages, which in most of the metamorphosed areas show a dextral slip direction. The results show that the shear zone of NW of Khoy, has been formed within the dextral transpression tectonic zone.

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References

 
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Advanced Applied Geology
Volume 14, Issue 3
In progress
October 2024
Pages 671-678

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