Structural properties and tectonic signi ficance of a shear zone discovered within the Tauride orogen near Alanya, SW Turkey

A major shear zone, referred to as the Ye？il？z Shear Zone, was discovered in the lower Mahmutlar Nappe of the Alanya Nappe Complex in Alanya region. The nappe shows early transposed folds with axial metamorphic foliation and upright open folds formed during emplacement. The NW-trending shear zone is around 2 km wide and mappable over a length segment of 10 km. The shear zone consists of the metamorphic rocks of the host nappe, but with the phyllite mylonitized by vertical shear foliation and the quartzite and marble dispersed as lenticular bodies. These brittle rock bodies show broken upright folds similar as in the nappe, and also the phyllite shear lenses bear relics of the nappe metamorphic foliation. Analysis of kinematic indices in the shear zone points to a dextral transcurrent deformation. The emplacement of Mahmutlar Nappe caused mild metamorphism of the upper part of underlying nappe and also affected it with the development of the shear zone that extended downwards. The nappe underwent no further translational movement during and after the shear zone formation, which suggests that the ductile transcurrent deformation probably accommodated a residual shortening induced by the emplacement of the next, younger nappe of the Alanya Nappe Complex