Structural analysis of asymmetrical sheath folds of Kowlikosh shear zone, southwest of Iran Sarkarinejad, K. & Azizi, A

Category Tectonic & Seismotectonic
Group GSI.IR
Location 20th symposium on geosciences
Holding Date 16 April 2008

     Kowlikosh shear zone is part of the Sanandaj-Sirjan paired metamorphic belt. This zone consists of metamorphic rocks such as slate,phyllonite ,muscovite schist ,marble .This belt is strongly folded and thrusted most of asymmetrical folds are related to thrusts and compressional duplex structures. The fold axes show trends of W-E or. and they may show types-3 interference pattern, and effected by noncoaxial progressive inhomogeneous simple shear.
Forier series analysis reveals that these folds are highly and slightly asymmetrical and they have undergone three stages of deformation. They are as follow:
A) The first generation of folding (Dl) has affected area in the late Triassic.
B) Shearing and thrusting during the Alpine orogenic movement (D2) has lead to formation of type-3 interference patterns.
C) Formation of S-, Z-and M-folds within limbs and hinges of drag folds are related to flexural slip movements of later Tertiary orogenic phase (D3).
Department of geology, university of Shiraz

tags: FARS