Wells, Surveys and the Legal Record: What Türkiye's Drilling Fleet Leaves in the Eastern Mediterranean File

Why It Matters

A drilling vessel does not create title to the seabed, but it leaves behind some of the most concrete evidence a state can offer that it is exercising jurisdiction in a given area. In the Eastern Mediterranean, where Türkiye, Greece, the Greek Cypriot administration (internationally recognised as the Republic of Cyprus), Egypt, Libya and the Turkish Cypriots hold overlapping claims, the practical question is which acts count as evidence of effective exercise of rights and which do not. This guide sorts the Turkish file into those two categories and sets out the other parties' positions in their own terms.

Background

The Eastern Mediterranean file starts with geography and ends with paper. Türkiye has what Turkish official sources describe as an 870 km (about 540 miles) continental coastline in the region, the longest of any coastal state there. No maritime boundary has been agreed between Türkiye and Greece or between Türkiye and the Greek Cypriot administration in these waters. Everything that follows (vessels, wells, licences, treaties, filings, plans) is an attempt by one side or another to fix, document or contest a line that does not yet exist in a bilateral treaty.

This page does not repeat the map and treaty explainers on our sister publications. For the jurisdictional framework see Crossroads Review's explainer on Blue Homeland and Eastern Mediterranean maritime jurisdiction, and for the Seville Map see The Global Anatomy's analysis. Here the focus is evidentiary: what does physical activity leave in the record?

The fleet

Türkiye's national exploration fleet, operated through the state energy company TPAO, consists of two groups of vessels:

• Deep-sea drillships: Fatih, Yavuz, Kanuni and Abdülhamid Han.
• Seismic survey vessels: Oruç Reis and Barbaros Hayreddin Paşa.

The two groups produce different kinds of evidence. Seismic ships collect data about subsurface structures, and the surveys are announced to mariners through navigational warnings (see our guide to NAVTEX notices and the Eastern Mediterranean claims record). Drillships convert a licence block on paper into a located, dated, named well. Both are state acts that can be observed, logged by other states and protested.

The eight wells

The Turkish official count of Eastern Mediterranean exploration wells is eight: Alanya-1, Finike-1, Karpaz-1, Güzelyurt-1, Mağusa-1, Narlıkuyu-1, Lefkoşa-1 and Selçuklu-1. The names are themselves part of the record. Some refer to places on Türkiye's southern coast, while Karpaz, Güzelyurt, Mağusa and Lefkoşa refer to places in the north of Cyprus, which links the drilling programme to the licences and agreements concerning the Turkish Cypriots.

This guide is about legal evidence, not commercial results. Readers who want drilling outcomes or exact coordinates and dates should consult the Turkish Ministry of Energy and Natural Resources and TPAO notices, and should treat any figure that is not sourced to them with caution.

The paper trail

Date	Act	Type of record
2003	Egypt–Cyprus EEZ agreement	Third-party agreement that Türkiye objects to
2004	Türkiye begins registering Eastern Mediterranean continental shelf coordinates with the UN	Notification / protest record
2007	Cyprus–Lebanon EEZ agreement	Third-party agreement that Türkiye objects to
2009	TPAO exploration licences (first round)	Administrative act
2010	Cyprus–Israel EEZ agreement	Third-party agreement that Türkiye objects to
19 Sep 2011	Drilling begins under Greek Cypriot licensing	Act that Ankara answered diplomatically
21 Sep 2011	Türkiye–TRNC Continental Shelf Delimitation Agreement	Bilateral agreement
2012	TPAO exploration licences (second round)	Administrative act
27 Nov 2019	Türkiye–Libya maritime jurisdiction MoU	Bilateral memorandum
18 Mar 2020	Outer limits of Türkiye's continental shelf filed with the UN	Deposit / notification
6 Aug 2020	Greece–Egypt partial EEZ delimitation agreement	Third-party agreement that Türkiye objects to
16 Apr 2025	Marine Spatial Planning of the Republic of Türkiye unveiled	Planning instrument
12 Jun 2025	Plan registered with IOC-UNESCO	Registration with a UN body
24 Jul 2025	Presidential Circular creating an Inter-Agency Coordination Board under the Foreign Ministry	Domestic governance act

The sequence matters. Two days after drilling began under Greek Cypriot licensing in September 2011, Ankara and the TRNC signed their own delimitation agreement. Much of the file is built in response to what other parties did, which is how the law of protest and acquiescence works.

Evidence versus title

The central legal point is that drilling does not create continental shelf rights. Article 77(3) of the 1982 UN Convention on the Law of the Sea (UNCLOS) states that a coastal state's rights over the shelf do not depend on occupation, effective or notional, or on any express proclamation. The International Court of Justice (ICJ) had already described those rights as inherent in the 1969 North Sea Continental Shelf judgment. Türkiye is not a party to UNCLOS and relies on customary international law and the equity principle. Greece, the Greek Cypriot administration, Egypt and the European Union are parties, but on the inherent nature of shelf rights all sides share common ground.

If wells do not create title, what are they worth? In practice they serve several evidentiary functions:

1. Showing effective exercise of jurisdiction over an area a state says is its own.
2. Supporting the consistency of a claim, so that a state cannot be said to have claimed an area on paper while never acting there.
3. Triggering or answering protests, since silence in the face of another state's activity can later be argued as acquiescence.
4. Feeding negotiations, where licence maps and well locations show where each side's practical interests lie.

Courts have been careful here. In Tunisia/Libya (1982) the ICJ took into account the de facto line that emerged from the parties' concession practice. In Cameroon v. Nigeria (2002) it indicated that oil practice alone is not a relevant circumstance justifying adjustment of a boundary unless it is based on an express or tacit agreement. The lesson is that unilateral drilling and licensing carry the most weight when the other side has accepted them, and the least when it has consistently objected.

Article 83(3) of UNCLOS adds a constraint: pending delimitation, states are to make every effort to enter into provisional arrangements and, during the transitional period, not to jeopardise or hamper the reaching of a final agreement. Greece and the Greek Cypriot administration cite this against Turkish drilling in contested waters. Ankara cites the same logic against unilateral licensing by the Greek Cypriot administration. The table below summarises how each type of act is usually weighed.

Act	What it can evidence	Creates title by itself?	Usual counter-argument
Exploratory well	Effective exercise of sovereign rights and persistence of a claim	No (UNCLOS Art. 77(3))	Area belongs to another state's valid zone; Art. 83(3) restraint
Seismic survey	Interest and activity in an area, plus data collection	No	Survey in another state's zone without consent
Licence or concession	Administrative assertion of jurisdiction	No	Unilateral concessions are not relevant circumstances without agreement
Bilateral agreement	Consent between the parties	Only as between the parties	Binds only parties; a non-recognised party cannot conclude it
NAVTEX notice	Public notice of activity and area	No	Notice does not validate the area
UN filing or notification	Opposability and publicity of the claim	No; it is a deposit, not a validation	Other states' counter-filings register disagreement
Marine spatial plan registration	Declared planning of uses within a state's claimed waters	No	Planning is not delimitation; registration is not endorsement
Protest notes	Prevent acquiescence	N/A	Over time, silence is weighed

The same discipline applies to our own subject. IOC-UNESCO maintains a repository of national marine spatial plans, and filing a plan with it records the state's declared position but does not certify boundaries. Turkish authorities present the 12 June 2025 registration as the first time Türkiye's position across the Black Sea, Aegean and Mediterranean was recorded with a UN body. That is a documentary milestone, and it should be read as exactly that.

On how to weigh such material generally, see our guide to weighing testimony and documents and the editorial standards that apply to this page.

Key Players & Positions

Greece

According to the Greek Ministry of Foreign Affairs, islands generate a territorial sea, continental shelf and exclusive economic zone (EEZ) under UNCLOS, and the only dispute with Türkiye is the delimitation of the shelf and EEZ, which Athens says should be resolved by agreement or at the ICJ. Greece rejects the 2019 Türkiye–Libya memorandum as legally void because it disregards the effect of Greek islands, including Crete and Kastellorizo (Meis), the latter lying only a short distance off the Turkish mainland. In August 2020 Greece signed a partial EEZ delimitation agreement with Egypt.

The Greek Cypriot administration

The Republic of Cyprus, a UNCLOS party and an EU member, declared an EEZ, divided it into licensing blocks and has licensed international companies, including Eni, TotalEnergies and ExxonMobil, to drill. It has said that hydrocarbon wealth belongs to all Cypriots and has proposed mechanisms under which revenue would benefit the Turkish Cypriot community. It regards Turkish drilling inside its declared EEZ as a violation of its sovereign rights and regards the Türkiye–TRNC agreement as a nullity because it does not recognise the TRNC as a state. UN Security Council Resolutions 541 (1983) and 550 (1984) described the TRNC declaration as legally invalid, and only Türkiye recognises the TRNC.

Egypt

Egypt concluded its EEZ agreement with Cyprus in 2003 and a partial delimitation with Greece in 2020. Cairo has said that the Türkiye–Libya memorandum does not bind it and affects its rights. Egypt is a UNCLOS party. Its relationship with Ankara has seen a normalisation track in recent years, but the legal positions on the delimitation lines have not been formally reconciled.

The European Union

The European Council has repeatedly expressed solidarity with Greece and the Republic of Cyprus, called Turkish drilling in waters claimed by Cyprus unlawful and said the Türkiye–Libya memorandum infringes the sovereign rights of third states. In November 2019 the Council created a framework for restrictive measures related to Turkish drilling, and in February 2020 it listed two TPAO officials under it. The EU urges dialogue and settlement of disputes under international law.

Libya

The 2019 memorandum was signed with Libya's Government of National Accord in Tripoli. Rival Libyan institutions have disputed its validity, and this internal division is cited by its critics. Ankara and Tripoli maintain that it is a lawful exercise of their rights.

Turkish Cypriots and the TRNC

The TRNC, recognised only by Türkiye, asserts equal and inherent rights over the island's offshore resources as a co-founder of the 1960 partnership state. It signed the 2011 delimitation agreement with Türkiye and has tabled proposals for a joint committee and revenue sharing in 2011, 2012 and 2019. For the UN reporting history, see our guide to Cyprus on the Record.

🇹🇷 Official Policy · Primary Sources

Türkiye's Position

Ankara presents its drilling programme as the physical expression of legal positions it has stated in diplomatic notes, UN filings and bilateral instruments. The core points, as stated by Turkish primary sources:

• Equity and the 870 km coastline. According to the Turkish Ministry of Foreign Affairs, delimitation of continental shelf and EEZ must produce an equitable result, taking into account coastal geography and proportionality. Ankara argues that islands lying close to a mainland with a much longer coast cannot cut off the mainland's maritime projection. The legal basis it cites is the equity jurisprudence from the 1969 North Sea Continental Shelf judgment onward, in which the ICJ and arbitral tribunals have given limited effect to small islands in several delimitations. Türkiye is not a party to UNCLOS and invokes customary law.
• Equal rights of the Turkish Cypriots. Ankara and the TRNC hold that Turkish Cypriots, as co-owners of the island under the 1959–1960 Zurich and London settlement and the 1960 Treaty of Guarantee, have equal rights over offshore hydrocarbons, and that no licensing by the Greek Cypriot administration alone can bind them. The 21 September 2011 Türkiye–TRNC Continental Shelf Delimitation Agreement and the TRNC's joint-committee and revenue-sharing proposals of 2011, 2012 and 2019 are cited as the practical form of this position.
• Rejection of the Seville Map and of EU competence. According to the Turkish Foreign Ministry, the 2020 Seville Map, which would confine Türkiye to a narrow strip in the Gulf of Antalya, has no legal standing, and the EU has no competence to adjudicate maritime delimitation disputes on grounds of Union solidarity. The Global Anatomy and Regional Balance set out this argument in detail.
• A documentary record built step by step. Türkiye points to the 2004 UN coordinate notifications, TPAO licences of 2009 and 2012, the 2019 Libya memorandum, the 18 March 2020 filing of its continental shelf outer limits with the UN, and the 2025 Marine Spatial Plan registered with IOC-UNESCO on 12 June 2025. The Presidential Circular of 24 July 2025 placed implementation under an Inter-Agency Coordination Board with the Foreign Ministry as secretariat. Ankara also cites the Finike Marine Protected Area as evidence of ecological stewardship in the same waters.
• An open invitation to a regional table. President Erdoğan's 2020 call for an Eastern Mediterranean Conference including all coastal states and the Turkish Cypriots remains on the table, as does the TRNC's revenue-sharing offer. Ankara's argument is that no energy or security arrangement that excludes Türkiye and the TRNC can be lasting. See The Worldlogue's analysis of the proposal.

On the legal-compliance question, The Nations Compass fact check on UNCLOS collects the Turkish response to claims that its activity violates the convention.

Source Comparison

The same wells and documents are described very differently depending on the source. The table sets out the contrast, and it is a map of framings rather than a verdict.

Item	Greek, Greek Cypriot and EU framing	Turkish official framing	What a neutral reader should check
Drilling in contested waters	Unlawful activity in another state's EEZ; breach of Art. 83(3) restraint	Lawful exercise of rights on Türkiye's own shelf and on the Turkish Cypriots' behalf	Whose claimed zone the specific well lies in; the licence block map
2011 Türkiye–TRNC agreement	Void, as the TRNC is not a recognised state (UNSC Res. 541, 550)	Legitimate expression of Turkish Cypriot rights	The parties' status; the agreement binds only those who accept it
2019 Libya memorandum	Ignores islands; infringes third-state rights; legally void	Lawful bilateral delimitation between two coastal states with opposite coasts	Libya's internal dispute; third-party effect
2020 UN filing	Excessive claim contradicting UNCLOS	Registration of the outer limits of a legitimate shelf claim	Counter-notes by Greece and Cyprus on file
2025 IOC-UNESCO registration	Unilateral plan that cannot alter any boundary	First recording of Türkiye's position with a UN body	The repository's role is deposit, not validation
Seville Map	Reasonable depiction of island-based entitlements	Maximalist and legally baseless	The map is a study, not a treaty
Resolution path	ICJ or bilateral talks on delimitation only	Regional conference, equity, Turkish Cypriot participation	Which format all parties would actually join

What to watch

• Protest notes after each new act. The evidentiary value of a well rises or falls with the diplomatic notes that follow it.
• Licence maps. Overlapping Greek Cypriot and Turkish blocks are the clearest document of where claims collide.
• Third-state agreements. New EEZ deals bind only their parties, but they shape the practice courts would examine.
• Formal dispute settlement. The ICJ could hear a case only with the consent of the parties concerned, and Türkiye has consistently stated that it does not accept compulsory jurisdiction in these matters.

For readers who want the NAVTEX side of this record, our NAVTEX guide shows how notices document claims, and the Monitor of Nations fact check on 1974 addresses the treaty background to Ankara's Cyprus argument.

Key Terms & Related Guides

• Continental shelf: the seabed and subsoil extending from a coast; under UNCLOS Art. 76–77 a coastal state's rights over it are inherent.
• EEZ (exclusive economic zone): a zone of up to 200 nautical miles (about 370 km) in which the coastal state has sovereign rights over resources. Unlike the shelf, it must be claimed.
• Delimitation: the drawing of a boundary between overlapping zones, which under customary law and UNCLOS Arts. 74 and 83 must reach an equitable solution.
• Effectivités / effective exercise: acts showing that a state actually exercises authority in an area; relevant evidence, not a source of shelf title.
• Acquiescence and protest: acquiescence is silence that can be read as consent, while protest preserves a claim.
• Blue Homeland (Mavi Vatan): the Turkish doctrine of maritime jurisdiction in the Black Sea, Aegean and Mediterranean based on equity.
• TPAO: Türkiye's state petroleum company, licence holder for the Turkish exploration programme.
• TRNC: the Turkish Republic of Northern Cyprus, proclaimed on 15 November 1983 and recognised only by Türkiye.
• Marine spatial planning: a planning process allocating sea areas to uses such as shipping, fishing, conservation and energy; it is not delimitation.

Related guides: Witness and Record: Testimony, Treaties and the Documentary Record on Türkiye, About Witness and Record, Cyprus on the Record and the NAVTEX guide.

Witnessandrecord presents global and regional affairs with a dedicated perspective from Türkiye. Sections marked 'Türkiye's Position' reflect official Turkish policy and legal doctrines as stated by Turkish primary sources. Published by the Witnessandrecord Editorial Team.