The Structural and Sedimentological Evolution of the Prinos Basin, Greece

Stuart David Harker and Adrian J. Burrows
PGS Reservoir Ltd, Aberdeen, United Kingdom

The Prinos Basin is a NE-SW trending rift basin (30 x 15km) between the mainland and Thassos Island in the northern Aegean Sea. The Prinos oilfield is located on a gravity-slide anticline in the north-central part of the basin. The basin formed following the mylonitization of the Symlovon-Kavala coastal batholith in early Miocene. It resulted from extension perpendicular to NE-directed compression in western Greece. Metamorphic and igneous rocks, with a strong NNE structural grain, outcrop around the basin,.
A sequence stratigraphic approach has identified six unconformity bounded sequences for which new nomenclature is introduced. The basin is 6km deep and the earliest fill (Peramos Group) is followed by southerly progradation of three Miocene “Gilbert type” deltas of the Ammodhis Group. These are thickest in the north where they reduced the rectangular basin form to a square. Deep marine sediments of the Rachoni and Prinos groups followed, onlapping the delta margin to the north and the uplifted South Kavala Ridge to the south. They include both source rocks and reservoir intervals. There was isolation of the basin from oceanic circulation in the late Miocene and the Messinian Kavala Evaporite Group forms an effective top-seal overstepping earlier sequences.
Mio-Pliocene gravity sliding into the basin created detached folding. Movement was slow, and basement controlled faults caused the slides to “pile up” in local compressional ridges. The final sequence is a southwesterly prograding Pliocene deltaic succession across the entire basin. This Nestos Group marks the return to oceanic circulation.

AAPG Search and Discovery Article #90072 © 2007 AAPG and AAPG European Region Conference, Athens, Greece