Petrofabric analysis of the Chaharsoton-Deshwan fault area, northwest Salmas

Author

Department of Geology, Khoy Branch, Islamic Azad University, Khoy, Iran

Abstract

The Chaharston-Deshwan fault area is located to the northwest of the city of Salmas in the Sanandaj–Sirjan zone.The area consist highly deformed rocks which have been emerge clearly in a dextral shear zone. Mesoscopic and microscopic scale analysis carried out for determining the deformation history of the area. Thus tectonics structures and microstructures measured and analyzed based on field study and statistical method. Then fitting structural models were offered for each of them. According to the results, it can be concluded that four different deformation phases were efficacious in formation of the analyzed structures.The most important deformation mechanism including: foliation, S-C fabrics, mineral fish, Z drag folds, mantled porphyroclasts throughout the field area indicate dextral deformation. The most reliable shear sense markers in high grade shear zones are shear bands, mineral fish, mantled porphyroclasts, sigmoid and asymmetric bounding. This shear sense indicators indicate that the Chaharsoton-Deshwan area deformed via dextral transpression tectonic regime.

Keywords

References

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Advanced Applied Geology
Volume 11, Issue 3
October 2021
Pages 514-535

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