The Alpine evolution of Thessaly (NW Greece) and Late Tertiary Aegean kinematics

Abstract

The Aegean region is one ofthe most studied regions currently undergoing post-orogenic extension. Numerous kinematic and dynamic models have been proposed to account for its active tectonics. Most recent studies have demonstrated that, since the onset ofextension in the early Miocene, there has been a major reorganisation ofthe regional kinematics in the last 5 Ma. Hence, the mechanisms and models which account for active deformation may not necessarily be extrapolated backwards in time. To date little is known about either the Tertiary kinematic evolution ofthe Aegean or the exact kinematic configuration before and after the post 5 Ma reorganisation. This thesis reconstructs the Alpine kinematic evolution oftheNW Aegean and then uses this information to place constraints on possible models for the Alpine tectonic development of the Aegean area. Initially, this thesis concentrates on the structural and metamorphic evolution ofthe Thessaly region of northern Greece which is situated near the northwest margin ofthe area ofAegean extension. A field study was carried out to determine lithological subdivisions, and their kinematic and metamorphic history in the Thessaly region. The size ofthe area selected lies between the scale of previous local studies and regional studies of Aegean tectonics. The location ofthe studied area, which lies between the well-studied areas ofthe Cycladic islands and Mt Olympos, means that the data presented and models formulated in the course ofthis study provide a crucial geographical and structural link in an Aegean-wide synthesis. Most importantly, it also provides a comprehensive set ofkinematic constraints on regional dynamic models for the tectonic evolution ofthe Aegean area.