Subscribe free to our newsletters via your
. Earth Science News .

Subscribe free to our newsletters via your

Deep Ocean Mining In Prospect

The oil and gas industry went offshore in a major way in the mid-1940s. Today, about one-third of the world's oil comes from under the sea. There are producing wells in 1,500 meters of water off the coast of Brazil, and there is drilling some 2,500 meters down in the Gulf of Mexico.
by Staff Writers
St Louis MO (SPX) Feb 19, 2006
A Canadian geologist predicts the world is on the brink of a new era of deep-ocean mining of mineral deposits. Steven Scott, with the University of Toronto, said advances in marine geology and deep-ocean technology have combined to make possible going more than two kilometers (about 6,000 feet) underwater for gold and other minerals, and two start-up marine-mining companies - Nautilus Minerals and Neptune Minerals - are actively exploring deep seafloor deposits.

Neptune is assessing deposits to which it holds the rights in territorial waters north of New Zealand's North Island. Nautilus and its joint-venture partner, Placer Dome - a Canadian gold-mining company - are collecting samples from a deposit to which Nautilus holds the rights in the Bismarck Sea off the eastern coast of Papua New Guinea.

Speaking at the American Association for the Advancement of Science annual meeting, Scott said the big question for the companies is the economic potential of undersea deposits of polymetallic sulfides, sulfur-rich seafloor ore bodies produced worldwide in underwater volcanic regions by structures called black smokers.

Black smokers form when seawater seeps into the porous sea bottom, is heated and re-emerges through vents carrying dissolved minerals. When hot water hits cold seafloor water, the minerals precipitate, creating the chimney-like towers. Over time, the towers collapse and accumulate to form ore deposits, some of which are rich in gold, silver, copper, lead and zinc.

Scott was the first mining geologist to explore black smokers. In 1982 he joined members of the Scripps Institute of Oceanography and the Woods Hole Oceanographic Institution in the submersible Alvin to explore newly discovered black smokers 2,000 meters below the waves in the Gulf of California off the coast of Mexico. He said that after more than two decades of promoting the possibility of mining the deposits created by black smokers, the present ventures represent a move that has required mining companies to cross a watery psychological barrier.

"Twenty years ago," he said, "most mining companies didn't want to hear about this possibility. They thought it was too difficult, but now some are seeing that it's a lot easier to go down through a couple of thousand meters of water than through a couple of thousand meters of rock."

Scott said that at present, the deepest undersea mines - diamond mines off the coast of southern Africa - are under just a few hundred meters of water, but the offshore oil and natural gas industry has developed technologies that can extend that range significantly.

The oil and gas industry went offshore in a major way in the mid-1940s. Today, about one-third of the world's oil comes from under the sea. There are producing wells in 1,500 meters of water off the coast of Brazil, and there is drilling some 2,500 meters down in the Gulf of Mexico.

The key challenge is developing technology to extract mineral ore from the depths. Scott said he envisions the use of "deep sea versions of robotic coal mining machines," which pipe ore up to mining ships, or semi-submersible platforms such as those used by the offshore oil industry. He said deep-sea robotics is a mature industry, driven in large part by the needs of offshore oil exploration and recovery.

Deep-sea mining technology was given a major kick-start by the approximately $650 million spent internationally in an aborted effort to develop sea floor manganese nodule mining technology in the 1970s and '80s. Manganese nodules, often rich in nickel and copper, are formed by the slow precipitation of the minerals from seawater. The nodules cover vast areas of the deep ocean floor known as the abyssal plains.

Scott said he initially was drawn to black smokers as a way of understanding the formation of polymetallic sulfide deposits on dry land, such as those mined at the Kidd Creek copper and zinc mine in northern Ontario, and in many other countries in the world, including the United States.

"We wanted to know whether marine geology held clues for the occurrence of these terrestrial deposits - and it does," Scott said, adding that one of his postdoctoral students has returned from a vessel drilling Nautilus claims off the Papua New Guinea coast. She is exploring the role that bacteria play in creating these mineral deposits.

"Getting samples from the interior of these deposits is rare," Scott said. "What we're interested in from the perspective of pure science is what microorganisms are in these deposits and what they're doing. Are they in fact causing mineralization?"

Regarding environmental impact, Scott said he thinks deep undersea mining could be less damaging than terrestrial mining. "The ocean mining companies are going to have environmental problems like there are with any industrial process," he said. "There's understandably going to be legitimate concern from many in the public."

Seafloor mining avoids many of the problems associated with terrestrial mining, however, Scott continued. There is no acid mine drainage, because acids are neutralized by the alkaline seawater. Because sulfide deposits sit on the sea floor, they require no excavation or waste-rock piles, and no permanent structures would be left behind. The mining also would not touch active black smokers, regions known to support a rich diversity of submarine life.

Scott said although he sees their economic potential, he also supports protecting black smokers. He has advocated establishment of the world's first deep-ocean park, the Endeavour segment of black smokers along the Pacific submarine Juan de Fuca Ridge, off Canada's west coast.

Related Links
Nautilus Minerals
Neptune Minerals

  • Ancient Climate Studies Suggest Earth On Fast Track To Global Warming
  • NJIT Solar Physicists Report Paradox: Less Sunlight, But Temps Rise
  • Antarctic Snow Inaccurate Temperature Archive
  • Plant Enzyme Efficiency May Hold Key To Global Warming

  • Cornell To Create Plan To Manage Mass Casualties In Disasters
  • Experiment To Test Crisis Planning
  • US Hands Over Kashmir Relief Equipment To Pakistan
  • Damning Report Says Katrina Response A 'National Failure'

  • ALOS Captures First Image of Fujiyama
  • Southern Greenland Glaciers Dumping Ice Faster
  • NASA Satellite Technology Helps Fight Invasive Plant Species
  • NASA, UNH Scientists Uncover Lost Maya Ruins From Space

  • No Change In India Energy Policy
  • Brazil Seeks To Bolster Ethanol Sector
  • Scepticism Over Bush's Call For Dramatic Cut In Mideast Oil Imports
  • Russia Muzzles Experts Critical Of Oil Pipeline To Asia

  • New Influenza Vaccine Takes Weeks To Mass Produce
  • Bird Flu Hits Western Europe
  • 1,500 Cholera Cases In Flood-Hit Mozambique
  • Bird Flue Hits Africa

  • Search For Alien Life Challenges Current Concepts
  • Next Good Dinosaur News Likely To Come From Small Packages
  • Phytoplankton Bounce Back From Abrupt Climate Change
  • Sex, Cleaner Of Genomes

  • Study Finds No Safe Level For Ozone
  • A Microbial Biotechnology Prescription For Global Environmental Health
  • Chirac Lifts Warship Hurdle Ahead Of Asian Tour
  • France Under Pressure To Bring Home Asbestos Warship

  • Snows Of Kilimanjaro Disappearing, Glacial Ice Loss Increasing
  • Rewriting Glacial History In Pacific North America
  • Most Of Arctic's Near-Surface Permafrost May Thaw By 2100
  • New Technique Shows Glacial Pace Of Erosion Was Not So Slow

  • The CONTENTS herein, unless otherwise known TO be PUBLIC domain, are Copyright 1995-2005 - SpaceDaily. AFP AND UPI Wire Stories are copyright Agence France-Presse AND United Press International. ESA Portal Reports are copyright European SPACE Agency. ALL NASA sourced material IS PUBLIC domain. Additional copyrights may apply IN whole OR part TO other bona fide parties. Advertising does NOT imply endorsement, agreement OR approval OF ANY opinions, statements OR information provided BY SpaceDaily ON ANY web page published OR hosted BY SpaceDaily. Privacy STATEMENT