Transpression in Khoy area

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

     Evidence of both ductile and brittle deformation is present in this region. Outcrops of ductile shear zones show strikes (NW-SE) similar to ophiolitic outcrops, and major brittle structures. Study of shear senses in outcrops and thin sections show dextral strike-slip
movement with some reverse component in ductile shear zones. Comparison between the kinematic analysis of shear senses and syn-deformational meso-scale folds with N-S axes, show a strain partitioning during ductile deformation. In outcrops of pillow lava, there are two sets of faults, which were created in a single deformation phase. These two sets of faults have similar NW-SE to N-S strikes but have two different mechanisms: strike-slip and reverse. These mechanisms show strain partitioning during brittle deformation as well. Comparison of kinematic analysis in ductile shear zones and brittle structures indicate that these deformations were created in a single deformational event but in different (physical) conditions. Strain partitioning in brittle and ductile deformation and tectonic setting of region indicates a dextral transpression zone in tectonites of Khowy area