Petrofabric and finite strain analyses of deformed Samen granitoid

Document Type : علمی -پژوهشی

Abstract

Structural and micro-structural studies on Samen deformed granitoid revealed both brittle and ductile deformation in this granitoid. Joints and dextral faults are the most important of brittle structures that developed in the different scales. Field studies and micro-structural observation show development of penetrative stretching lineation related to the quartz and feldspar minerals elongation in the Samen granitoid. This lineation shows a textures same as striated gneiss fabric. Petrofabric elements such as; quartz bands and lamellas, symmetric and asymmetrical quartz and feldspar lenses, sigma type porphyroclasts, C-S shear bands and evidences of dynamic recristalisation are the most important features in the Samen granitoid. All the shear sense indicators show a dextral sense of shear in the area. Finite strain analyses on the quartz grain markers show the amounts of tectonic strain as: 2.35

Keywords

References

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