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September 23, 2013

Deep-sea mining

BY: Nicolas Fournier



It is often said that we know more about our moon than the ocean’s depths. Though this is an exaggeration, the truth is that science is only starting to understand the complex physical, chemical and biological process ruling the underwater world.

For several years research projects in the Pacific Ocean have been studying seabed minerals, including manganese, copper, nickel, zinc or cobalt. The first polymetallic nodules were discovered at the end of the 19th century, but at that time it was not economically profitable to exploit them. Unfortunately times have changed and as terrestrial mines become depleted, and demand continues to grow (e.g. for electrical devices and electronics such as smartphones) prices rise and the quest for new sources of supply has now turned towards the seabed.  

Deep-sea mining is extremely harmful to marine habitats as it literally tears up the seafloor and vacuums up large amounts of sediments and rocks, to extract the minerals from, and then returns the debris back into the sea. Not only does it shatter the habitats, but the fine sediment spreads to surrounding waters, smothering large areas and impacting the wider marine food chain.

This type of mining is the equivalent of open-cut mining on land, and it inevitably alters the fragile equilibrium of deep-sea ecosystems. What’s worse is that some of the places rich in mineral deposits – like hydrothermal vents, fracture zones or seamounts – happen to be the biodiversity “hot-spots” of the abyss, which are protected by international conventions!

Oceana is concerned that the European Union, in an effort to recover from the economic crisis, has announced its intention to develop marine mineral resources as a priority focus area of its Blue Growth Strategy. As you can imagine, we are opposing this decision. It is unacceptable that policy makers once again are blinded by short term interests that will do more harm than good in the long run.