A comparison of geodetic and finite strain pattern in the Aegean, geodynamic implications

A comparison of the active strain pattern of the Aegean constrained by global positioning system measurements, and the Oligo-Miocene finite strain field shows some striking similarities in terms of direction and rates of extension. The geometry of extension at crustal scale is also very similar with north-dipping normal faults connecting near the brittle-ductile transition to shallow north-dipping shear zones. This pattern of extension is not significantly modified by the recent extrusion of the motion of Anatolia and Aegea. The persistence over more than 25 Myr of the same pattern of extension suggests that the cause for extension resides within the Aegean lithosphere. Gravitational collapse allowed by extensional boundary conditions after 30 Ma (slab retreat) is the primary cause for post-orogenic extension in the Aegean and Western Anatolia. (C) 2001 Elsevier Science B.V. All rights reserved.