As countries scramble for minerals, the seabed beckons. Will mining it be a disaster? – visual explainer

Deep-sea mining has been proposed as a source of critical metals and minerals for decades, but mining companies now say the technology is almost ready to make this a reality.

Mining has not begun yet but 2025 is set to be a crucial year. The International Seabed Authority (ISA), the regulator, has a new leader promising an era of openness, with meetings planned in March and July to discuss the next steps.

Mining contractors are pushing for regulations to be agreed by the year’s end and one company hopes to apply to begin mining in 2026. Any country can apply for a mining contract in the name of the company it sponsors.

At the same time, a growing number of countries, companies and scientists are pushing for a moratorium on the activity.

With so much uncertainty around deep-sea mining, these maps and charts help explain what we know to date about the issue.

How does deep-sea mining work?

Deep-sea mining is a method where minerals and metals are extracted from the ocean floor. It involves a surface vessel at sea, which deploys underwater mining vehicles to the seafloor.

Illustrations are not to scale.

These remotely operated vehicles collect deposits such as polymetallic nodules, seafloor sulfides or cobalt-rich crusts.

One method involves sucking them up chutes to the ship, which will filter out the metals. Unused sediment would then be deposited back into the sea.

Another method would use “hovering” remotely operated vehicles to minimise the impact of sediment disturbance.

Other potential environmental impacts are vast – but there is a lot of uncertainty.

This is largely because research is only now being undertaken on the number of animals and organisms living in these inaccessible areas.

Academics estimate that there are thousands of species at risk in the CCZ alone – and new species are recorded every year.

The creatures that could be affected are still being discovered.

Whether these are clams, mussels or shrimp that thrive around hydrothermal vents, or crabs, corals, anemones or that live on the walls of seamounts, or sea stars and giant worms on the abyssal plains, these species are still being found, which increases the uncertainty over what would happen if they are removed from the ecosystem.

Research has found mining noise and lights could affect sealife, sediment deposits could bury and wipe out habitats, toxic elements could be released in the mining process, and mining nodules may even affect oxygen production processes that we know little about.

There are also concerns that, because these deep-sea communities change slowly, the impacts of any activity could reach long into the future.

Muriel Rabone, a deep-sea ecologist at the Natural History Museum, pointed to the specific risks involved in this ecosystem – especially when less than 1% of the seafloor has been fully explored. She said:

This is quite a remarkable high-diversity, low-abundance environment, and so many organisms that live here have interesting adaptations to deal with the deep sea. There is a vast reservoir of diversity for human society. For example, there are species that have antimicrobial adaptations, or sponges that work like fibreoptics. There is a crazy amount of knowledge that we could use, whether that's in industry, medicines or to tackle climate change.

Do we actually need these metals?

It is claimed by some that the current level of supply cannot match demand for critical minerals, which could hinder the transition to clean energy.

While technological innovations and societal attitudes make predictions difficult, the Energy Transition Commission (ETC) has modelled annual supply estimates running to 2030.

'Where are we going to put our values?'

The Deep-Ocean Stewardship Initiative (Dosi) project has argued for a "sufficient information requirement" to be surpassed for deep-sea mining, ensuring that it doesn't take place until enough is known about the likely effects to avoid unforeseen damage.

Experts say this information isn’t available. A report from 2022 said that nearly nine in 10 experts agreed that current scientific knowledge is too sparse to ensure the protection of the marine environment.

Dr David Santillo, a marine scientist with the Greenpeace Research Laboratories based at the University of Exeter, said:

“Uncertainty is high: that's almost an inevitability because we're talking about an environment that is so deep.

"So the debate comes down to, who do you give the benefit of the doubt to? Do you give it to the mining industry, and assume that deep-sea mining will be OK? Or do you say that too little is known and we shouldn’t pursue this? There’s a growing consensus of scientists and countries coming to the second conclusion. But then the next question is, could we ever get to a point where the science would tell us that it is possible to mine the seabed sustainably?”

There’s also an existential point here: this environment could be one of the origins of life on Earth. Are we going to impact that for car batteries and smartphones? Where are we going to put our values?

A growing number of businesses – including car manufacturers such as BMW, Rivian, Renault, Volvo and Volkswagen, and smartphone leaders Google and Samsung – support a moratorium on deep-sea mining. Countries including France, Greece, Canada and Mexico also support it.

As she assumed the role of Secretary-General of the ISA earlier this year, Leticia Carvalho said:

“The deep seabed is one of Earth’s least explored frontiers, yet its ecosystems are vital to the health of our ocean and the planet. Our mandate is both a privilege and a responsibility — to act in the interest of all humankind and future generations.”

There are concerns that – even without the information gaps being filled – countries and mining companies might start in the coming years.

The Metals Company, a leading deep-sea mining firm based in Canada, is aiming to submit its application to the ISA in July and hopes the agency will finish its mining code in the coming year.

This seems unlikely. Carvalho has said a lot of work needs to be done before the code is finalised and has spoken of “constructing a consensus” on what needs to be done in 2025.

In 2023, ISA’s council adopted a decision that underlines that commercial mining should not be carried out without regulations.

However, countries could act unilaterally, with some predicting that more countries will apply to the UN to extend their own continental shelf, giving them the right to exploit a larger area.

While Norway’s plans to exploit its own deep seabed are paused, the country’s prime minister made it clear that “preparatory work” would continue on regulations and environmental impact mitigations.

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Methodology

The mineral deposits map is sourced from the US Geological Survey.

The exclusive economic zones (EEZs) map is sourced from the Flanders Marine Institute.

Data on the number of exploration contracts sponsored by country is sourced from the International Seabed Authority (ISA).

The Clarion-Clipperton Zone map was sourced from Thomas Webber and the ISA.

The map of whale and dolphin sightings is sourced from the OBIS-SEAMAP project . The full source is Halpin, P.N., A.J. Read, E. Fujioka, B.D. Best, B. Donnelly, L.J. Hazen, C. Kot, K. Urian, E. LaBrecque, A. Dimatteo, J. Cleary, C. Good, L.B. Crowder, and K.D. Hyrenbach. The data is filtered to just show recorded sightings since 2000.