The Geography of the World's Largest Deep-Sea Mining Rush

The Clarion-Clipperton Zone (CCZ) is the most intensively targeted area for deep-sea mining on Earth. Stretching approximately 4.5 million km² across the central Pacific Ocean between Hawaii and Mexico — an area larger than the contiguous United States — it holds the world's largest known deposit of polymetallic nodules. Understanding the CCZ is essential for anyone tracking deep-sea mining policy, biodiversity loss, or the geopolitics of the clean energy transition.

Where Is the Clarion-Clipperton Zone?

The CCZ lies between roughly 7° and 15° North latitude, bounded to the northwest by the Clarion Fracture Zone and to the southeast by the Clipperton Fracture Zone — the geological fault lines that give the region its name. It sits entirely in international waters, placing it under the jurisdiction of the International Seabed Authority (ISA) rather than any single state.

Water depths range from 4,000 to 5,500 metres. At these depths, the seafloor is cold (around 1–2°C), pitch-dark, and subject to pressures exceeding 400 atmospheres. Currents are sluggish, sedimentation rates are extremely slow, and biological processes that would take weeks at the surface can take thousands of years.

What Makes the CCZ So Valuable?

The nodule fields of the CCZ contain extraordinary concentrations of strategically critical metals:

• Manganese — used in steel alloys and battery cathodes
• Nickel — essential for lithium-ion battery chemistries (NMC, NCA)
• Copper — the backbone of electrification infrastructure
• Cobalt — a critical component in high-energy battery cells

The United States Geological Survey estimates that the CCZ alone holds more nickel and cobalt than all known terrestrial reserves combined. Some industry assessments value the nodule resource at several trillion US dollars, though extraction costs, environmental regulations, and technology readiness make commercial viability highly uncertain.

Who Holds Contracts in the CCZ?

As of 2026, the ISA has issued 17 exploration contracts in the CCZ — more than half of all active seabed exploration contracts globally. Contractors include:

• The Metals Company (Canada/Nauru, Tonga, Kiribati) — the most commercially advanced nodule mining project
• NORI (Nauru Ocean Resources Inc.) — targeting the NORI-D block in the eastern CCZ
• State entities from China, South Korea, Japan, France, Germany, Belgium, and the United Kingdom
• GSR (Global Sea Mineral Resources) — backed by Belgian dredging company DEME

Each contract covers an exploration area of up to 75,000 km², divided into two portions (one relinquished after eight years) to prevent monopolisation.

The Biodiversity Crisis Hidden on the Seafloor

The CCZ is not a mineral deposit floating in empty water. It is a functioning ecosystem — and one of surprising richness, given its remoteness and depth.

Research expeditions, including the ABYSSLINE project and surveys by the Natural History Museum London, have documented over 5,000 species in the CCZ, with estimates suggesting more than half are new to science. Key ecological communities include:

Nodule-associated fauna: Sponges, xenophyophores (giant single-celled organisms), holothurians (sea cucumbers), brittle stars, and polychaete worms colonise the nodule surfaces. These nodules are the only hard substrate available on the otherwise soft sediment plains — making them habitat, not just resource.

Sediment infauna: Foraminifera, nematodes, and other meiofauna are extraordinarily diverse in CCZ sediments. Their populations and recovery rates following disturbance are poorly understood.

Megafauna: Fish, crustaceans, and octopuses use the CCZ floor. Populations are sparse but ecologically connected across vast distances.

The IUCN has assessed the CCZ as one of the highest-priority areas for pre-mining biodiversity baseline research, noting that the knowledge gaps are so severe that impacts cannot currently be meaningfully predicted.

Mining's Impact on CCZ Ecosystems

Nodule mining involves collector vehicles crawling the seafloor and vacuuming up the top 10–15 cm of sediment along with the nodules. This process:

1. Physically destroys all nodule-associated fauna in the collection path

2. Generates a sediment plume — a cloud of disturbed particles that can travel hundreds of kilometres, smothering filter feeders and reducing light penetration

3. Creates a discharge plume — water pumped back to the seafloor after nodule separation on the surface vessel, laden with fine sediment and altered chemistry

4. Prevents recovery: Nodules grow at 1–10 mm per million years. The substrate destroyed in a single mining pass will not recover on any human timescale.

The 1989 DISCOL experiment (a deliberate sediment disturbance in the Peru Basin) is still being monitored today. After 26 years, fauna diversity and biomass had not recovered to pre-disturbance levels.

Areas of Particular Environmental Interest (APEIs)

In recognition of biodiversity risk, the ISA established nine Areas of Particular Environmental Interest in the CCZ — areas set aside from mining contracts to serve as environmental refugia and comparison reference points. Each APEI covers approximately 160,000 km².

However, independent scientific assessments have raised serious concerns:

• APEIs were designed without adequate biodiversity data and may not be representative of CCZ habitat types
• Some APEIs are located in areas with lower nodule density (biasing them away from the most ecologically rich zones)
• Their boundaries cannot be revised without renegotiating existing contracts

The ISA has acknowledged these limitations and committed to a review, but the timeline remains unclear.

The Moratorium Debate

As of 2026, several member states have called for a precautionary pause or moratorium on CCZ exploitation contracts until environmental standards are strengthened:

• France, Germany, Chile, New Zealand, Palau, Fiji, and Samoa have formally supported a moratorium or precautionary pause
• Pacific Island nations most directly threatened by climate change — and some of the same nations sponsoring mining contracts — are divided on the issue
• The ISA's Mining Code, which would set the rules for any exploitation, remains unfinished

No exploitation contract has been issued. The CCZ is currently in an exploration-only phase.

Tracking the CCZ in Real Time

Abyssal Claims maps all 17 CCZ exploration contracts alongside hydrothermal vent fields, OBIS biodiversity data, and APEI boundaries. Filter by contractor, contract date, or resource type to understand which areas are under pressure and how they overlap with documented ecological communities.