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

Mining companies are poised to mine the deep sea – but opposition is growing. What is the environmental cost, and are these metals actually needed?

## 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.

## 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.

## Likely exploration areas

There are plenty of critical mineral deposits. They broadly fit into three categories:

- **crusts**, where cobalt-rich deposits are fixed to underwater ridges and seamounts;
- **hydrothermal vents**, where hot, metal-rich fluids discharge and accumulate to form deposits;
- **nodules**, where unattached potato-sized polymetallic deposits are scattered across the seabed at depths of 4,000 to 6,000 metres.



## Where are we going to put our values?

The Deep-Ocean Stewardship Initiative (Dosi) project has  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  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 :

> “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.

## Methodology

The mineral deposits map is sourced from .

The exclusive economic zones (EEZs) map is sourced from .

Data on the number of exploration contracts sponsored by country is sourced from .

The Clarion-Clipperton Zone map was sourced from .

The map of whale and dolphin sightings is sourced from the . 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.
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