National Geographic News
An underwater robot samples a seafloor vent.

A black smoker of a seafloor massive sulphide system.

Image courtesy Nautilus Minerals

Meghan Miner

for National Geographic News

Published February 1, 2013

A mile beneath the ocean's waves waits a buried cache beyond any treasure hunter's wildest dreams: gold, copper, zinc, and other valuable minerals.

Scientists have known about the bounty for decades, but only recently has rising demand for such commodities sparked interest in actually surfacing it. The treasure doesn't lie in the holds of sunken ships, but in natural mineral deposits that a handful of companies are poised to begin mining sometime in the next one to five years.

The deposits aren't too hard to find—they're in seams spread along the seafloor, where natural hydrothermal vents eject rich concentrations of metals and minerals.

These underwater geysers spit out fluids with temperatures exceeding 600ºC. And when those fluids hit the icy seawater, minerals precipitate out, falling to the ocean floor.

The deposits can yield as much as ten times the desirable minerals as a seam that's mined on land.

While different vent systems contain varying concentrations of precious minerals, the deep sea contains enough mineable gold that there's nine pounds (four kilograms) of it for every person on Earth, according to the National Oceanic and Atmospheric Administration's (NOAA) National Ocean Service.

At today's gold prices, that's a volume worth more than $150 trillion.

Can an Industry Be Born?

But a fledgling deep-sea mining industry faces a host of challenges before it can claim the precious minerals, from the need for new mining technology and serious capital to the concerns of conservationists, fishers, and coastal residents.

The roadblocks are coming into view in the coastal waters of Papua New Guinea, where the seafloor contains copper, zinc, and gold deposits worth hundreds of millions of dollars and where one company, Nautilus Minerals, hopes to launch the world's first deep-sea mining operation.

Animation: How Robots Could Mine Seafloor

Source: Nautilus Minerals

Last year, the Papua New Guinean government granted the Canadian firm a 20-year license to mine a site 19 miles (30 kilometers) off their coast, in the Bismarck Sea in the southwestern Pacific Ocean. The company plans to mine the site, known as Solwara 1, by marrying existing technologies from the offshore oil and gas industry with new underwater robotic technologies to extract an estimated 1.3 million tons of minerals per year.

Samantha Smith, Nautilus's vice president for corporate social responsibility, says that ocean floor mining is safer, cleaner, and more environmentally friendly than its terrestrial counterpart.

"There are no mountains that need to be removed to get to the ore body," she says. "There's a potential to have a lot less waste ... No people need to be displaced. Shouldn't we as a society consider such an option?"

But mining a mile below the sea's surface, where pressure is 160 times greater than on land and where temperatures swing from below freezing to hundreds of degrees above boiling, is trickier and more expensive than mining on terra firma.

Nautilus says it will employ three remote-controlled construction tools that resemble giant underwater lawn mowers to cut the hard mineral ore from the seafloor and pump it a mile up to a surface vessel.

That vessel would be equipped with machinery that removes excess water and rock and returns it to the mining site via pipeline, an effort aimed at avoiding contaminating surface waters with residual mineral particles. The company would then ship the rock to a concentrator facility to remove the mineral from the ore.

An Unknown Impact

At least that's the plan.

But the ocean floor is still a mysterious place, seldom visited by humans, compounding the known difficulties of working at sea.

Scientists weren't even able to prove the existence of underwater hydrothermal vents until 1977.

That year, an expedition of geologists, geochemists, and geophysicists from the Woods Hole Oceanographic Institute, Oregon State University, the Massachusetts Institute of Technology, Stanford University, and the U.S. Geological Survey proved their existence in the Galápagos rift with cameras and a manned dive in the submersible Alvin.

The animal-rich landscape and huge temperature shifts came as a surprise.

"When the first people went down there, and saw these things, they had no idea," says Mike Coffin, a geophysicist and executive director of the Institute for Marine and Antarctic Studies at the University of Tasmania in Australia. "The submersible had windows that could melt at temperatures lower than what was coming out of the vent."

And, in contrast to the desert-like landscape that the scientists expected, it turns out that hydrothermal vents are home to lots of life: snails the size of tennis balls, seven-foot-long (two-meter-long) tubeworms, purple octopi, and all-white crabs and skates.

It turns out that, far from the sun's life-giving light, the same minerals now eyed by the mining industry support lively communities.

Now some researchers fear that deep-sea mining could jeopardize those communities by altering their habitats before the systems have been fully explored and explained.

"We're still just grappling with this reality of commercialization of the deep sea," says Cindy Van Dover, director of Duke University's Marine Lab. "And scrambling to figure out what we need to know."

Van Dover was aboard the first manned biological exploration of the hydrothermal vents in 1982 and was the only woman to pilot the submersible Alvin. Despite the strides that have been made in understanding the deep sea, she says, it's still a young science.

When it comes to the impacts of mining on any deep-sea life, "there's a particular type of research that needs to be done," she says. "We haven't yet studied the ecosystem services and functions of the deep sea to understand what we'd lose.

"We don't yet know what we need to know," Van Dover says.

Conservationists also say they want to know more about the vent ecosystems and how they will be mined.

"The whole world is new to the concept of deep-sea mining," says Helen Rosenbaum, coordinator of the Deep Sea Mining Campaign, a small activist group in Australia that campaigns against mining the Solwara 1 site.

"This is going to be the world's first exploitation of these kinds of deep resources. The impacts are not known, and we need to apply precautionary principles," she says. "If we knew what the impacts were going to be, we could engage in a broad-based debate."

Rosenbaum says some communities in Papua New Guinea are raising concerns about the sustainability of local livelihoods in the face of mining and say they aren't receiving the information they need.

The Deep Sea Mining Campaign is especially concerned about the impacts of toxic heavy metals from the mining activities on local communities and fish. The group claims that the Environmental Impact Statement for the Solwara 1 mine hasn't effectively modeled the chemistry of the metals that would be stirred up by the mining process or the ocean currents that could transport them closer to land.

"The Solwara 1 project is scheduled to be a three-year project," Rosenbaum says. "The mining company thinks they'll be out of there before there are problems with heavy metal uptake. We might not see the effects for several years."

A report released in November 2012 by the Deep Sea Mining Campaign ties exploratory pre-mining activities and equipment testing by Nautilus to "cloudy water, dead tuna, and a lack of response of sharks to the age-old tradition of shark calling."

Shark calling is a religious ritual in which Papau New Guineans lure sharks from the deep and catch them by hand.

Another concern for Deep Sea Mining Campaign: Papua New Guinea's government has a 30 percent equity share in the minerals as part of a seabed lease agreement with Nautilus.

The company and government are currently involved in a lawsuit over these finances, but the Deep Sea Mining Campaign says government investment could compromise its regulatory efforts.

Mining for Dollars

Nautilus' Smith insists that the company has taken a careful and transparent approach. "The biggest challenge the company faces," she says, "is funding."

Fluctuations in commodity pricing, the high cost of working underwater, and financial disagreements with the Papua New Guinean government have been setbacks for Nautilus.

Last November, the company announced that it had suspended construction of its mining equipment in order to preserve its financial position. Smith says that Nautilus is still committed to finding a solution for its work in Papua New Guinea, and that the company could still extract minerals as early as 2014.

Other companies around the world are also exploring the possibility of mining throughout the South Pacific.

The International Seabed Authority, which regulates use of the seafloor in international waters in accordance with the United National Convention on the Law of the Sea, has granted 12 exploratory permits to various governments—including India, France, Japan, Russia, China, Korea, and Germany—in roughly the last decade.

And as long as the promise of riches await, more firms and governments will be looking to join the fray.

"It's economics that drive things," says the University of Tasmania's Coffin. "Tech boundaries are being pushed, and science just comes along behind it and tries to understand what the consequences are. Ideally, it should be the other way around."

Adam Sherritt
Adam Sherritt

What I love is how everyone on here is probably sitting in a relatively newly built home in the comfort of climate control.  Writing on a computer which has the same minerals in it that this company is trying to extract while texting on a phone with the same.  I could go on and on.  People want a modern life without any of the side effects.  Don't get me wrong,  I live and grew up on the ocean.  Its part of me.  But I also understand human nature and how our desire for comfort trumps our desire for an untouched landscape.  We have a mentality that we are above nature on the food chain that goes back millennia.  We believe God gave us this earth for our benefit.  The world is not a single organism that only works properly when all parts are working as nature intended.  There is us and then there is the world.  We need to change our mentality and then and only then can we change the destruction to the only planet we have.  Personally I think we will realize that too late.  But find comfort in this, you'll be dead by that time.  Just like "the bankers" of Wall street really didn't care if the system collapsed because hey, in the end "I'll be gone."

jetty venkatesh
jetty venkatesh

You can extract the valuables but you don't have any right to destroy the nature.

So stop doing that.

Lane Harbour
Lane Harbour

This brings new meaning to Wallerstein's World Systems Theory and the core's exploitative relationship with the periphery. I can't say that I'm surprised, but I am disappointed. 

Georgia Green
Georgia Green

It's sad that we have to destroy all this natural beauty all for what a few measly diamonds. We need to leave at least one of a natural environments to be explored and properly discovered and not mined for our own greed.

Rebeca Ware
Rebeca Ware

The company says it will have trouble operating because PNG government gets 30%. Oh gee, is this too much to ask? This country and its people will suffer the long term effects for the rest of their lives and their future generations, just so some greedy folks can take it now. How can this developing country even expect to develop rules and regulations for this type of mining operation or prepare for the impacts if "the company" wont even give them 30%. Seems typical take from the needy and give to the greedy. Check out what the Nickel company is doing in the same area.

C. Cyr
C. Cyr

Oh great, it's not enough for us to screw up the Earth's land & air, now we've got to exploit the ocean too in the name of greed for precious metals, etc. If the ocean dies eventually everything will die as it is the beginning of the food chain (i.e. algae & plankton). It's high time the human race realizes that this planet's biosphere is more important than we are as it can always evolve another sentient species. We need the planet, but the planet does not need us.

Rodman Papros
Rodman Papros

ocean floor–the safest place to do something fishy

Albert Batista
Albert Batista

Tragic news! Once all the mining platforms are out there, where is all their additional pollution going? Goodbye Barriers and Reefs!

Ken Truitt
Ken Truitt

Each mining operation should be required to simultaneously conduct some kind of study to promote the environment and add to our understanding of this unique region.  They will add to science just by doing what they're doing, but additionally they should be required to do some kind of studies, both on the extent of their impact on the environment but also just simple science of the region (deep sea).

Richard Alexander
Richard Alexander

Is it necessary to mine active vents? I understand that inactive vents exist, in which all those life forms have died out. 

I'm excited by the prospect of deep sea mining, but I also want to see nature protected and preserved, particularly the rare, poorly-understood and beautiful deep sea life. I hope that commercial entities could fund scientific expeditions, as happens in other parts of the world.

Frank Johnson
Frank Johnson

I sincerely hope this does not happen. 

These deep sea vents are where the earliest life forms were formed.

Who knows how long it will take before people on the surface start noticing the die offs or better yet, how long it will take before someone who has a megaphone can get their voice heard by the rest of the world.

Corporations want to mine these thermal vents not just because of the value of the concentrated minerals but because there are no laws or regulations yet governing the protection and well being of the seafloor fauna and its environment. It becomes even more lucrative because it's difficult for the public and environmentalists to ascertain or prove what is going on a mile below the ocean. Regular people do not exactly have the means to rent a submarine to take down to do any inspections.

Essentially, we are trusting these selfish profit-minded corporations to police themselves.- like they did with the our banks.

Like the "Wild West", the motto is "Just do it" and apologize later --and only if caught red-handed--meaning  the damages are discovered and can be traced back and directly attributed to the mining.

Corporations know no one is looking and even if  they are caught, it's still safe because no one's name or family are on the line since everyone hides behind a corporation.

This is very similar to what we saw with the collapse of the Wall Street banks. No one personally was arrested. The corporations get a slap on the wrist and then just pay a fine--which they easily can afford--and continue on.

There is already devastating pollution occurring on the land  in Papua New Guinea by giant mining corporations. Hoodwinked  by their own greedy leaders  whom were blinded by sincere ignorance and conscientious stupidity, the villagers have no audible voice. 

 What is out of sight is out of mind. The ocean's depths will provide a veil as the mines wreak havoc thousands of feet below. 

More whales and dolphins will start to mysteriously beach themselves and die and we will all believe the "scientists" when they say they "died of natural causes", as we continue to follow up on what the Kardashians are wearing. By then, it will be too late.

Robert Lee
Robert Lee

someday they might dig a china syndrome's tunnel  

allegre sleep
allegre sleep

self defeating.. if they mine that gold, the price will plummet.. it's hardly worth 150 trillion.

Val Livada
Val Livada

In the late 1970s the world went into a tizzy because Howard Hughes build a ship that was supposed to mine the vast manganese nodules deposits on the ocean floor.  The subsequent Law of the Sea conferences droned on for ever, ultimately resulting in the Treaty that guaranteed sovereignty over tracts of the ocean floor. 

It turned out that the US still hasn't signed that Treaty, nobody mined the manganese and Hughes' ship was a CIA ploy to recover a sunken Russian nuclear sub. deja vu all over again without the spies 

Daniel Knight
Daniel Knight

 @Georgia GreenIt's sad that people like you have to making begging the question fallacies with their comments, actually, why do you do that? Who said any natural beauty was being destroyed? And why don't you think imbecile: how much natural human beauty and man made would there be if morons like you were always whining and complaining mindlessly when any tree is cut down or a rock picked up? Get a life and think. Stop being simpleton leech. You're using a computer aren't you, to post your self centered hypocritical comments? You're like the idiots who say we're overpopulating, well then go kill yourself first and stop implying others should. Murder your own baby, not mine.

Daniel Knight
Daniel Knight

@Georgia Green It's sad that people like you have to making begging the question fallacies with their comments, actually, why do you do that? Who said any natural beauty was being destroyed? And why don't you think imbecile: how much natural human beauty and man made would there be if morons like you were always whining and complaining mindlessly when any tree is cut down or a rock picked up? Get a life and think. Stop being simpelton leech. You're using a computer aren't you, to post your self centered hypocritical comments? You're like the idiots who say we're overpopulating, well then go kill yourself first and stop implying others should. Murder your own baby, not mine.

Daniel Knight
Daniel Knight

@Georgia Green It's sad that people like you have to making begging the question fallacies with their comments, actually, why do you do that? Who said any natural beauty was being destroyed? And why don't you think imbecile: how much natural human beauty and man made would there be if morons like you were always whining and complaining mindlessly when any tree is cut down or a rock picked up? Get a life and think. Stop being simple.

Jeffrey Smith
Jeffrey Smith

They should limit mining to areas where the sea floor is spreading. This way they can mine the minerals that have already moved away from the active vent and not disturb this very fragile ecosystem. There could be a minimum distance from an active vent that they must maintain. It should be relatively easy and non-controversial to establish this distance by determined how far from an active vent these unique organisms are found.

Ed Wapole
Ed Wapole

@Craig Dillon Don't worry, the greedy liberals sucking on the .gov teat will get their "fair share".  The UN's Law of the Sea Treaty will tax the heck out of these mining companies.


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