GPS velocities of the Aegean region and Turkey with respect to Eurasia, from McClusky et al. (2000). Dark grey lines indicate boundaries between rigid lithospheric fragments. Areas where the motion between fragments is accommodated by regional deformation are shaded in light grey. The Aegean block, which comprises most of the Aegean Sea, the southern part of the Peloponnesus, Crete, and westernmost Turkey, moves as a rigid block. It is bordered by the Central Hellenic Shear Zone (CHSZ) to the northwest and by the Western Anatolian Shear Zone (WASZ) to the northeast. The Hellenic thrust belt marks the limits of the Aegean block to the southwest and to the southeast. Compared to the westward movement of Anatolia, the Aegean block has a more pronounced south-oriented velocity component.