The tectonic regimes along the convergent border of the Aegean Arc from the late Miocene to the present : Southern Peloponnesus as an example

ABSTRACT

Field analysis of fault kinematics demonstrates changes in the tectonic regime on the Aegean Arc border. During the Pliocene-Early Pleistocene extensional tectonics were active; extension trended radial retreat of a high angle-dipping slab which decreased the magnitude of the push on the Aegean lithosphere. During the Mid-Late Pleistocene compression has been active in the lowlands and extension in the highlands of the arc border, the extensional directions being orthogonal to the compressional directions and parallel to the arc border. It is suggested that this has resulted from a push of a low angle-dipping slab on the Aegean lithosphere. These stress patterns are interpreted at a large wavelenght as a result of a balance between the boundary forces acting along the arc border and the body forces due to the thickening of the crust. Rotations of the paleostress directions due to rigid rotations of the material and perturbations of the stress trajectories are also considered in analysis the paleostress maps of the Aegean