Aegean

Commentary

Exploration in the Aegean is confined to the mature Prinos area, which is now turning to CO2 storage, and the central and eastern Aegean is effectively closed to licensing by disputed Greek and Turkish claims. Turkey has not ratified UNCLOS and does not recognise Greek continental-shelf rights around the islands; in 2026 Ankara issued Navtex notices claiming coordination rights east of the 25th meridian and prepared a bill to formalise its maritime claims, and in October 2026 the two navies announced overlapping exercise areas in the Aegean. Greece's country view has improved, with Chevron and ExxonMobil taking deepwater blocks in 2025 and the government openly prioritising domestic production, but that activity lies south of Crete and the Peloponnese, so the country upside does not carry through. Outlook: Neutral.

Updated

October 8, 2026

Location

Description

The Aegean (USGS Province 4075) is an offshore province between mainland Greece and western Turkey, ranked 242nd of the world's provinces by the USGS on known petroleum volumes. It is a back-arc domain formed above the Hellenic subduction zone: extension driven by roll-back of the East Mediterranean slab began in the Middle Eocene, was widespread and arc-perpendicular in the Miocene, and since the Early Pliocene has been overprinted by strike-slip shearing linked to the westward propagation of the North Anatolian Fault, which forms the North Aegean Trough. The proven petroleum system lies in the north, in the Prinos–Kavala Basin off Thasos, a Middle Miocene rift on metamorphic Rhodope basement. Its fill comprises continental and marine pre-evaporitic clastics, a thick Upper Miocene evaporite sequence and Pliocene–Quaternary clastics. Organic-rich Miocene shales are the source, Upper Miocene turbiditic sandstones form the reservoirs, and traps are faulted rollover anticlines and pinch-outs sealed by the evaporites.

Summary

Home to Greece's only producing fields: Prinos, Prinos North and Epsilon, operated by Energean with a 100% interest, have produced about 130 MMBOE, and the nearby South Kavala gas field is depleted. Prinos production was suspended in May 2025 because of high operating costs and restarted in February 2026 on a leaner cost base. The concession is now being repurposed for carbon storage: HEREMA issued a 25-year CO2 storage permit in February 2026, the first in the Mediterranean, and the FEED contract for a first phase of 1 Mtpa was awarded in March 2026. Greece's new deepwater licensing, with Chevron and ExxonMobil, lies south of Crete and the Peloponnese, outside the province.