Chevron Expands Greek Offshore Push With Block 10 Bid as Türkiye Deal Runs in Parallel

Bosphorus News Energy Desk

Chevron has filed an official request to acquire a 70 percent stake in Block 10, an offshore hydrocarbon exploration license in the Kyparissia Gulf in the southern Ionian Sea, Greece's Ministry of Environment and Energy said on 28 May.

The block is currently held by HELLENiQ ENERGY. Chevron and HELLENiQ ENERGY also asked the Hellenic Hydrocarbons and Energy Resources Management Company, known as EDEYEP, to transfer the operator role from HELLENiQ ENERGY to Chevron.

If approved, Chevron will hold 70 percent of the license and become operator, while HELLENiQ ENERGY will retain 30 percent.

The timing matters. The ministry said the first and second research phases have been completed. The next decision concerns entry into the third and final phase, which involves an exploratory drilling operation.

EDEYEP is also assessing a request for an 18-month extension of the second research phase. That would give the incoming Chevron-HELLENiQ ENERGY consortium more time to assess existing 2D and 3D seismic data, along with data from nearby concession areas, before moving toward a drilling decision.

Greek Environment and Energy Minister Stavros Papastavrou presented Chevron's move as a vote of confidence in Greece's offshore energy strategy.

"Greece is steadily strengthening its position on the energy map of the Eastern Mediterranean," Papastavrou said. He also described the exploration and use of Greece's undersea resources as "a national affair" requiring institutional credibility.

The Fifth Greek Offshore Position in Three Months

The Block 10 application follows a larger February package, when Chevron and HELLENiQ ENERGY signed lease agreements with the Hellenic Republic for four offshore exploration areas south of Crete and the Peloponnese: South Crete 1, South Crete 2, South of Peloponnese and Block A2.

Those four areas cover roughly 47,000 square kilometres of deepwater terrain, with some zones exceeding 1,500 metres in depth. Chevron holds a 70 percent operating stake in each, while HELLENiQ ENERGY holds 30 percent.

Block 10 would become Chevron's fifth Greek offshore position in three months. It would also extend the company's Greek footprint from the Cretan and Peloponnesian blocks into the southern Ionian Sea.

The ministry's announcement placed Block 10 inside the same wider buildout, noting that Chevron and HELLENiQ ENERGY had already signed lease contracts with the Hellenic Republic for four new offshore areas south of Crete and the Peloponnese.

Türkiye Deal Runs in Parallel

Chevron's Greek expansion is moving alongside a separate framework with Türkiye.

On 5 February 2026, Chevron signed a memorandum of understanding with Turkish Petroleum Corporation, known as TPAO, covering possible joint exploration and production activities inside Türkiye and in third countries. The signing took place in Istanbul in the presence of Energy Minister Alparslan Bayraktar.

Bayraktar said after the ceremony that cooperation with Chevron could eventually support TPAO's target of reaching one million barrels per day in production.

The Chevron-TPAO memorandum does not authorize drilling and does not commit either side to a specific investment. It creates a framework to evaluate possible joint opportunities onshore and offshore, both in Türkiye and internationally.

That distinction is central to the story. Chevron is seeking defined equity and operating control in Greek offshore acreage. Its Türkiye track remains a framework for possible future cooperation. The two files are not legally or commercially equivalent.

One Company, Two Rival Energy Geographies

Chevron's regional portfolio now stretches across a wide arc. The company has producing gas fields offshore Israel, the Aphrodite gas field offshore Cyprus, exploration positions in Egypt, Libya's S4 onshore block, offshore licenses in Greece and a framework agreement with Türkiye.

That geography places Chevron close to several of the Eastern Mediterranean's unresolved political and maritime questions.

Türkiye and Greece maintain sharply different interpretations of maritime jurisdiction across parts of the Aegean and Eastern Mediterranean. Ankara also rejects the Republic of Cyprus' unilateral offshore licensing and says Turkish Cypriot rights must be included in any energy development around the island.

Block 10, located in the Kyparissia Gulf in the southern Ionian Sea, lies further west and outside the core Eastern Mediterranean dispute zones. The Cretan and Peloponnesian blocks, however, sit closer to the wider legal and strategic debate over maritime delimitation between Türkiye and Greece.

Chevron has not publicly addressed the jurisdictional dimension of its Greek offshore portfolio.

For Chevron, the logic is not to wait for the region's disputes to be resolved. The company is taking concrete positions where licenses, partners and drilling timetables are clearer, while keeping channels open elsewhere.

ExxonMobil is moving through a similar map. The company leads Block 2 in the northwestern Ionian Sea with Energean and HELLENiQ ENERGY, with a drilling rig expected in early 2027. ExxonMobil also signed its own memorandum with TPAO in January 2026 for possible Black Sea and Mediterranean exploration.

Chevron's Block 10 bid puts the contrast in sharper view. Greece and Türkiye continue to argue over maritime jurisdiction, Cyprus and the legal geography of the Eastern Mediterranean, but the large U.S. energy companies are not waiting for those disputes to be settled. In Greece, Chevron is seeking equity, operatorship and a possible route toward exploratory drilling in a named offshore block. In Türkiye, it has kept a non-binding channel open with TPAO. ExxonMobil shows a similar pattern. Türkiye is not outside the conversation, but it remains behind Greece in turning high-level energy diplomacy with U.S. majors into licensed acreage, committed capital and drilling decisions.