Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Folding Style in Metamorphic Rocks of Faryab Area(South-East of Sanandaj-Sirjan Zone)

Document Type : Original Research Paper

Authors
SH. Shafiei Bafti 1
S.A. Alavi 1
M. Mohajjel 2
1 University of Shahid Beheshti, Faculty of Earth Sciences, Department of Geology, Theran, Iran.
2 University of Tarbiat Moddares, Faculty of Basic Sciences, Department of Geology
10.22071/gsj.2008.58216
Abstract
     Faryab area at the southeastern part of the Sanandaj-Sirjan zone, containing the Paleozoic rocks in the internal part of Zagros Orogen, displays two folding episodes through a progressive deformation event. Axial planes of recumbent F1 folds dip moderately to the north and the axes also plunge moderately to NW - SW. F1 folds were generated in a flexural-flow condition in whole lithological units. Thrust faults were produced along the overturned limbs of the F1 folds. These thrusts are most abundant in the central domain, the north of Zartorosht Au-index. At the southern edge of the central domain, displacement of large slabs of calcschist with interbedded marble were produced by these thrust faults.
Overturned limbs were cut by ductile shear zones of thrusts and development of green-schist facies in these shear zones implying the medium dips for thrusting. F2 folds were developed by co-axially refolding of F1 that are well exposed in Pasefid, Zartorosht and Zehmakan anticlines. Structural data shows the variation of F2 axis between S45W - N80W directions. Interference patterns of Z on S, M on S and S on S indicate coaxial refolding F1 by F2 (Hook Type).
Keywords
Structural evolution
Deformation phases
Refolding
Deep structures
Faryab
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Scientific Quarterly Journal of Geosciences
Volume 16, Issue 64
Winter 2007
Pages 54-73