Shallow Structure and Recent Evolution of the Aegean Sea Deduced from the Seismic Reflection Analysis

Laure Martin, Jean Mascle

Together with the Tyrrhenian Sea, the Aegean Sea represents one of two marine basins still developing as a consequence of the subduction of the African lithosphere beneath Europe. Despite many geophysical similarities with the Tyrrhenian Sea, the Aegean displays a specific structural segmentation characterized by two distinct domains separated by the central Aegean.

To the north of the basin, the so-called North Aegean trough likely represents the western marine extension of the transtensive Anatolian transform fault zone. The northern margin of this area contains a series of disconnected, often thickly sedimented small basins that probably initiated during the late Miocene as a consequence of a dominantly north-south extension; typical uppermost Miocene (Messinian) formations can be observed on seismic grounds.

To the south, the Cretan Sea shows clear evidence of important distensive events occurring during two main episodes and following two main trends; a dominantly north-south-directed extension is responsible for most of the structural features detected along both the Cretan and southern Cyclades margins. This episode appears to have been active during latest Miocene, but seismic evidence of typical Messinian deposits is absent. During post-Miocene time, extension seems to have rotated toward a prevailing northeast-southwest direction and characterizes mostly the Peloponnesus margin. North-south extension is still active within the central Cretan Sea but appears restricted to the deepest areas. As a whole, the central Aegean is interpreted as a complex domain where a dominant transform r gime (to the north and east) and a prevailing extension (to the south and west) are interfering.

AAPG Search and Discovery Article #91032©1988 Mediterranean Basins Conference and Exhibition, Nice, France, 25-28 September 1988.