Six decades towards seabed mining

Materials World magazine
,
1 Dec 2016

As the MarMine Project completes its first exploratory expedition, Professors Kurt Aasly and Fredrik Søreide talk to Khai Trung Le about the potential and yet-unanswered challenges of seabed mining.

There are two places I can confidently say you and I have never been. The first is interstellar space. The second is a not much more realistically closer 6,000 metres under the sea. Yet, while the former is considered centre stage of a US$1 trillion mining industry that could begin as early as 2020 (see Materials World, October 2015, page 6), efforts in deep sea mining have floundered for the past two decades. However, following the successful first research expedition of the MarMine Project’s Polar King and the approach of Nautilus Minerals’ first deep sea gold and copper extraction attempt in 2019, a tidal shift may be approaching. 

The MarMine project, a collaboration between 15 predominantly Nordic institutes and offshore oil and gas interests including Statoil, Fugro and the Norwegian University of Science and Technology (NTNU), launched the three-week expedition of the Polar King research vessel to evaluate the mineral potential and wealth of geological formations along the Mohns Ridge area of the Norwegian Sea. This follows, among others, previous efforts from an NTNU and University of Bergen, Norway, collaboration mapping the potential of the Mid-Atlantic Ridge.

Professor Kurt Aasly, NTNU Department of Geology and Mineral Resources Engineering and MarMine project leader, said that Mohns Ridge had been chosen for its potential for seafloor massive sulphide (SMS) deposits, which have the potential for large quantities of base metals, following previous observation by the joint NTNU and Bergen research team. Professor Fredrik Søreide, NTNU Institute of Marine Technology, added, ‘One of the biggest advantages is that Mohns Ridge is in the Norwegian extended continental shelf, and not part of the international seabed. You come into the jurisdiction of the International Seabed Authority, and this is where many French, Russian, German and Chinese applications are.’

Søreide stated that China, Germany, South Korea and Canada among others have committed resources to exploring the potential of seabed mining, and researchers within the MarMine Project are now looking to recommend that Norway further explores deep sea mining, with Martin Ludvigsen, NTNU Professor of Marine Technology, stating that the country ‘should take greater advantage of these marine minerals in order not to be left behind. If we don’t, we could miss valuable possibilities and related industrial development.’ Aasly argues that Norway’s heritage in offshore oil and gas since the 1970s makes deep sea mining a natural fit for the country. ‘Utilising Norway’s proficiency in the new area of offshore mining may give Norway and Norwegian companies a great advantage, not only as a mining operator but also as a service supplier to offshore mining across the world.’ 

Onshore for 60 years

The potential for seabed mining was first recognised in the 1960s, first with the acknowledgement of potential mineral wealth to be found in nodules – rounded accretions of manganese and iron hydroxides on the seafloor – through to the confirmation of high-grade SMS deposits in the Manus Basin in Papua New Guinea by the Commonwealth Scientific and Industrial Research Organisation in 1991.

However, efforts to begin mining have failed to take off. Canadian underwater minerals exploration company, Nautilus Minerals, was due to begin copper extraction from a leased offshore site at 1,000 metre depths in Papua New Guinea in 2008 before they halted their plans as copper prices declined. In 2009, Maurice Tivey, Senior Geophysicist at the Woods Hole Oceanographic Institution, USA, remarked, ‘It seemed like Nautilus was in a real fast race to get the first mine on the seafloor. A lot of people thought it was too easy [and] I think a lot of us on the science side were actually relieved.’ Regardless, the most immediate hopes for first seabed mining continue to lie with Nautilus, which has since been scheduled to begin mining in offshore Papua New Guinea in 2013, 2017, and most recently announced a prospective start date at the end of Q1 2019 with the Solwara-1 Project – ‘if additional required funding is secured by June 2017’, according to the company’s November Toronto stock exchange announcement.

Although Norway’s offshore legacy is expected to provide technological advantages, Søreide noted that there are significant hurdles left to overcome. ‘The first main technical hurdle is making machines to crush, collect and pump material to the surface. Oil and gas rises to the surface by itself. Metals don’t. The second is depth. Some of these sites, especially nodules, are much deeper than conventional technology currently allows, which is around 3,000 metres. Some identified nodules of value are up to 5–6,000 metres, far deeper than oil and gas.’

Norway’s efforts are likely to remain a possibility only to be realised in the future, with Søreide, who has been exploring the potential of deep sea mining for almost 30 years, downplaying the likelihood of widespread mining within the next two decades. ‘During the 2016 Ocean Week conference in Trondheim, we asked representatives from all of the players working on the Mid-Atlantic Ridge whether we can start within the next 20 years? Everybody thought it would take more. If Nautilus becomes a success, it will begin much quicker. But we are still a few years away from that.’

The progress of deep sea mining technology has also stalled, which Søreide attributes to the lack of development within both public-funded and commercial interests. ‘The first commercially proven system is expected to be Nautilus. There was a boom in the 1960s, when everyone was exploring nodules, but nothing came about from it. But now we are in a second wave of interest, and with a maturing of technologies, from which companies like Nautilus are benefitting.’

An unknown element

Unsurprisingly, deep sea mining has come under regular opposition from environmental concerns, including the Deep Sea Mining Campaign, a collection of NGOs and university professors principally based around the Pacific Islands, Australia and New Zealand. These are centred on the lack of information on the environmental impact of mining, especially around hydrothermal vents, often regarded as the origin of life. These include impact on photosynthetic activity around reefs and sediment plumes exposing sealife to toxic metals.

However, Søreide noted that NTNU and Bergen were placing significant priority on investigating the potential impacts. ‘Our investigations are part of the EU MIDAS  Project, which conducts environmental assessment. NTNU is also part of the EU Blue Mining Initiative, which looks at technologies in exploration, and all of our projects have researchers from the Norwegian Institute for Water Research doing full environmental assessments over the sites we’re looking at for baseline studies.’

For now, Nautilus holds the key to the kingdom, while Aasly stated that the MarMine Project sets its sights on more realistic targets. ‘Our first cruise gave us a lot of good sample material and data. But it also raised a lot of new questions, and highlighted some areas where more effort is needed. Unfortunately we do not have immediate funding for a new cruise, but we are working on this.’