France steward of the world’s second largest maritime space is consolidating how seabed mineral resources are mapped, regulated and taxed across its exclusive economic zone (EEZ) and continental shelf. The official public portal quantifies the scale (about 10.76 million km² EEZ), the resources at stake (marine aggregates and potential deep‑sea metallic deposits), and the legal instruments guiding exploration and any prospective extraction on France’s MineralInfo portal.
Scale and resources across France’s EEZ and continental shelf
France’s overseas territories underpin an EEZ spanning roughly 10.76 million km² second globally which hosts both non‑metallic marine aggregates and potential metallic resources such as polymetallic sulphides, cobalt rich ferromanganese crusts and polymetallic nodules. The national portal details aggregate extraction zones in the Channel Atlantic façades, inventory work in French Guiana, and outlines an EXTRAPLAC process to secure additional continental‑shelf rights where the geological margin allows (MineralInfo).
Polymetallic nodules are manganese‑rich pebbles, typically 5–10 cm across, carpeting abyssal plains at 4 000–6 000 m depth. They accrete extremely slowly in concentric layers of manganese and iron with cobalt, nickel and copper around a nucleus such as a rock fragment or shark tooth (Ifremer explainer). These environments host a notable biodiversity: French researchers reported in 2016 that nodule‑bearing areas can be richer in species than surrounding abyssal zones, and surveys indicate that a very high share of species encountered often cited near 90% are new to science, underscoring the knowledge gaps and conservation stakes (Ifremer).
Marine aggregates vs potential metallic deposits
Marine aggregates (sands and gravels) are already produced under mining titles on the metropolitan façades. In 2015, production totalled around 2.94 million m³ (≈ 4.4 million tonnes), within total authorised volumes of about 15 million m³; production remained in the 2.7–3.7 million m³ range during 2014–2020 (MineralInfo data). By contrast, metallic resources in national waters are at inventory stage. Beyond the EEZ, France via Ifremer holds exploration contracts in the international seabed Area (see below), which authorise research and resource assessment but not exploitation (ISA exploration overview).
EXTRAPLAC claims and status
France continues to pursue continental‑shelf extensions beyond 200 nmi under Article 76 of the UN Convention on the Law of the Sea through its EXTRAPLAC programme, which has already secured several decisions adding to national sovereign rights over the seabed and subsoil. Public summaries note hundreds of thousands of square kilometres granted since 2015, with additional submissions in train (Ifremer – EXTRAPLAC support).
Domestic legal regime and maritime spatial planning
Prospecting, exploration and exploitation of non‑energy minerals in French marine areas are governed by the Code minier (Mining Code) and the Code de l’environnement, which require mining titles (e.g., prospecting authorisations, exploration permits, concessions) and full environmental impact assessments. Since 2019, decisions must be consistent with maritime spatial planning instruments the Documents stratégiques de façade (DSF) and with specific guidance for sustainable aggregate management (Document d’orientation général de gestion des granulats marins, DOGGM) (MineralInfo – governance).
A dedicated fiscal instrument strengthens environmental governance. Decree no. 2017‑32 of 12 January 2017 implements a levy for the exploitation of non‑energy seabed minerals on the continental shelf or within the EEZ, applicable to extractions from 1 January 2018. The decree specifies the base and coefficients used to calculate the amount due per substance, with proceeds intended to finance marine biodiversity programmes (Decree 2017‑32 on Légifrance) and (Article 2 – calculation).
Permitting and production: the marine‑aggregate baseline
Aggregate extraction is concentrated along the Channel Atlantic façades, where dredging titles are granted after impact studies and public inquiries. Annual production fluctuates with coastal and construction demand as well as environmental constraints. The national series shows volumes near 3.3–3.7 million m³ in 2017–2020, with site‑specific caps to manage seabed morphology, turbidity and benthic habitats; these constraints are embedded in licence conditions and spatial planning documents (MineralInfo – aggregates).
Monitoring relies on hydroacoustic surveys, dredge tracking and ecological indicators; cumulative effects are appraised through the DSF process. The DOGGM provides a methodology for defining compatible volumes and areas over multi‑year horizons, reinforcing predictability for operators while protecting sensitive habitats (MineralInfo – DOGGM/DSF).
International posture and ISA exploration contracts
Beyond national waters, the International Seabed Authority (ISA) allocates time bound exploration contracts. France (through Ifremer) holds:
- a polymetallic nodule contract in the Clarion Clipperton Zone (CCZ) of the North Pacific entitling up to 75 000 km² to be explored; and
- a polymetallic sulphides contract on the Mid‑Atlantic Ridge, signed on 18 November 2014 and running for 15 years in the first instance. ISA documentation confirms these entitlements and dates; Ifremer indicates the CCZ contract area is 75 000 km² (ISA – exploration areas), (ISA–Ifremer sulphides contract), and (Ifremer – mineral resources).
These contracts authorise research only. Recent scientific work including experiments and long term monitoring in the CCZ shows that disturbance from prototype collectors can reshape meiofaunal communities and that recovery trajectories are uncertain, decades after tests (Ifremer research on CCZ impacts) and (deep‑sea disturbance synthesis). Ifremer’s public explainer emphasises that biodiversity and ecosystem functioning in these habitats remain insufficiently known to predict cumulative effects confidently (Ifremer explainer).
France’s stance in 2025 and implications for EU policy
France has coupled domestic governance with a precautionary international position. At the UN Ocean Conference hosted in Nice in June 2025, the Presidency reiterated support for protecting the deep sea on the high seas from mining, calling for precaution and stronger scientific baselines before any exploitation regime proceeds (Élysée statement, 9 June 2025). This built on France’s earlier calls since 2022 for a ban or moratorium and efforts to expand a coalition of like‑minded states at the ISA (French MFA – ISA Council).
EU Parliament debates and policy signals
The European Parliament has repeatedly urged a moratorium on deep‑sea mining in areas beyond national jurisdiction, most explicitly in its 6 October 2022 resolution on ocean governance, which “reiterates” the call and presses the Commission and Member States to act accordingly (European Parliament resolution, 6 Oct 2022). A 2023 parliamentary question and answer summarised that Parliament had made this call three times, with the most recent without conditions (EP Q&A, 17 Apr 2023). The Commission’s 2022 Joint Communication on International Ocean Governance likewise set a precautionary course, signalling support to prohibit deep‑sea mining until scientific gaps are closed and the marine environment can be effectively protected (EPRS brief on IOG, 4 Nov 2022), a framing echoed in civil‑society syntheses of Member State positions (Seas At Risk report, 2024).
French Polynesia: autonomy, moratorium and science needs
French Polynesia, whose EEZ overlays large swathes of nodule provinces and cobalt‑rich crust prospects, has asserted a precautionary stance at the local level. The Assembly adopted a moratorium on deep‑sea mining in December 2022; in 2025 the Presidency reaffirmed that position, emphasising ecological risk, cultural values and the need for baseline science (Presidency of French Polynesia, 21 Feb 2025). Public remarks by President Moetai Brotherson in April 2025 reiterated opposition to mining, while noting the institutional complexity whereby France retains competence over “strategic materials” (press interview, 1 Apr 2025). This layered governance underscores why French scientific inputs many led by Ifremer in Polynesian waters are central to future choices.
Box Cobalt‑rich crusts on the Tuamotu Plateau (French Polynesia)
Cobalt‑rich ferromanganese crusts accrete on hard‑rock seamounts and plateaux swept by currents over millions of years, forming pavements that can be centimetres to decimetres thick. Ifremer cruises have documented such crusts across the Tuamotu Plateau since the late 1980s, including sampling during the NODCO‑D campaign in March 1987 (Ifremer – Tuamotu crusts geochemistry) and subsequent syntheses on deposit diversity along Polynesian seamounts (Ifremer – geological environments). Early geochemical work highlighted platinum‑group elements alongside cobalt and nickel in selected samples (Ifremer – Pt group elements in Tuamotu crusts), establishing a scientific baseline for today’s environmental and resource assessments.
Outlook: science thresholds and decision points
Three interlocking conditions will shape any transition from exploration to exploitation:
1) Baseline science and monitoring. Robust inventories of benthic biodiversity, connectivity and ecosystem functions are prerequisite to evaluating irreversible harm. The nodule provinces are species rich yet low‑density, with many species undescribed; Ifremer notes frequent discovery of taxa new to science and stresses the need to resolve plume dynamics and far-field impacts before scaling any activity (Ifremer).
2) Technology maturity and environmental performance. Collector systems, lift technologies and at sea processing must demonstrate predictable, verifiable impact envelopes. Evidence from industrial test campaigns points to heterogeneous footprint and slow recovery, counselling caution when extrapolating from small scale trials to industrial operations (Ifremer – CCZ trial assessment).
3) Governance, fiscal tools and social licence. France’s levy on non‑energy seabed minerals and the embedding of mining titles within the DSF/DOGGM framework set a clear domestic compliance baseline (Decree 2017‑32). Internationally, France’s advocacy for a ban or pause—paired with holding ISA exploration contracts—positions Paris to demand stringent rules, full‑cost environmental accounting and equitable benefit‑sharing if exploitation were ever considered.
Takeaway. France’s approach pairs active mapping and stringent permits at home with a precautionary stance abroad. Given ecological uncertainties and contested cost‑benefit claims, any move from exploration to extraction will depend on stronger science, proven low‑impact technology and clear multilateral rules.
