Seafloor riches

The mining industry has belatedly realised there’s a mineral bonanza beneath the sea.  HUGH DE LACY explains.

Strange that it’s been so long coming, given that offshore oil exploration has been underway for 60 years, but the seafloor has suddenly become the new frontier for mineral mining and New Zealand is right at the heart of it.

The significance of offshore oil exploration to seafloor mining is that much of the former’s technology is applicable to the latter, the main difference being that collection of much of the mineral resource is arguably easier because it tends to sit on or near the seabed as much as under it.

Yet the generally recognised first offshore petroleum drilling rig began production in three metres of water in the Ship Shoal area of the Gulf of Mexico off the southeastern coast of Louisiana way back in October 1947.

By contrast, it wasn’t until November 2005 that Australia’s Nautilus Minerals claimed to have launched the world’s first drilling programme for seafloor massive sulphide (SMS) deposits in the Manus Basin off the coast of Papua-New Guinea.

The probable explanation for the slow application of seafloor exploration technology to minerals is the huge boom in demand for oil after World War II, nearly half a century after the Spindletop gusher in Beaumont, Texas, signalled in 1901 that oil was an abundant resource, and 30-odd years after Henry Ford’s Model T brought motoring to the masses in 1912.

No comparable explosion of demand occurred for minerals.

Also, throughout the 20th Century it continued to be more economic to mine for minerals on land, and only lately has it been realised that the low-hanging land-based mineral fruit has long since been plucked, and it’s time to look under the oceans that cover two-thirds of the planet.

Whatever the reason for the belated uptake, seafloor mining is beginning to take off, with New Zealand’s vast exclusive economic zone looking like becoming to mining what Texas was to oil.

The primary focus of the search by seafloor mineral explorers is the Kermadec Arc, which stretches 2500 kilometres from the Bay of Plenty almost to Tonga, and features a complex succession of “black smoker” volcanoes spewing out SMS deposits rich in zinc, gold and copper.

Aside from Nautilus, the other pioneering explorer has been Neptune Minerals which is based in Australia and was launched on the London Stock Exchange in 1999 specifically to seek SMS deposits in the South Pacific, and New Zealand waters in particular.

In the last couple of years Neptune has been granted three exploration licences by Crown Minerals under the 1964 Continental Shelf Act, covering the Colville Ridge, the Southern, Central and Northern Kermadec Ridges and the Havre Trough.

Nautilus too is expanding its focus from Papua-New Guinea to New Zealand, and has applied for prospecting licences covering 48,200 square kilometres of the Kermadec Arc.

While Neptune and Nautilus have been the first out of the blocks, they’re likely to be followed by a veritable rush of others in the wake of the closure in May this year of a United Nations deadline for countries to stake claims on the seabed up to 563 kilometres from their coasts.

This deadline was set in 1982 by the UN’s Convention on the Law of the Sea and, while it passed without much public fanfare, behind the scenes there was frenetic activity going on.

In what the UN has described as the last major redrawing of the world map, 48 countries – including New Zealand, which has potentially the most to gain – submitted claims, and dozens more made preliminary filings, under the Commission on the Limits of the Continental Shelf mechanism.

Those countries that didn’t meet the deadline have probably lost any chance of joining the bonanza.

The claimant countries won’t own the actual sea-floor beyond their 200-mile (322-kilometre) exclusive economic zones, and the seas above remain international waters, but they will have exclusive rights to the minerals.

In New Zealand’s case this has meant a 42 percent increase in its seafloor rights to a whopping 5.7 million square kilometres.

Inevitably the land-grab has pitched many countries into new rivalries, though New Zealand has avoided this by quickly reaching a tentative deal with Australia to its west, and by having virtually no contestants in the open sea in all other directions.

The Arctic Circle, to which Russia laid claim in 2001, is likely to become the focus for many Northern Hemisphere scrambles for mining rights, with Canada, Denmark, Norway and the United States also laying claims.

The Arctic scramble has not been repeated at New Zealand’s end of the world because the 1959 Antarctic Treaty banned mineral exploitation and suspended all sovereignty claims.

One such suspended claim is that of the United Kingdom which has not made a submission under the Continental Shelf mechanism but has reserved the right to do so should the Antarctic Treaty be modified in future.

The UK did, however, lay a claim to the continental shelf round the Falkland Islands over which it fought a colonial-style war with Argentina in 1982 – and predictably Argentina has already disputed it.

But that’s away round the other side of the planet in the South Atlantic, and is no cause for worry for New Zealand which can enjoy the luxury of contemplating its new-found potential riches at its leisure.

However, what has happened in New Zealand’s domain, probably as a result of Nautilus’ and Neptune’s endeavours rather than the UN deadline, has been a sudden upsurge in interest in exploration of the existing exclusive economic zone.

An expanding cluster of local and overseas companies has filed permits for an encyclopaedia of seafloor minerals ranging far beyond the standard gold, silver, copper and zinc.

Take the little Chatham Phosphate company for instance, which has filed to seek phosphorite nodules on the Chatham Rise between the South Island and the Chatham Islands.

Not only is the company hoping to replace the imports of agricultural phosphates which these days come mostly from Morocco, but it has also listed the following compendium of minerals (in alphabetical order) as being of interest: aggregate, aluminium, andesite, antimony, basalt, bentonite, clays of both high and low quality, copper, dacite, diatomite, dolomite, dunite, feldspar, gemstones, gold, granite, gravel, ignimbrite, ilmenite, iron, lead, limestone, marble, nickel, perlite, platinum group metals, pumice, quartz, rare earths, rhyolite, sand, serpentinite, silica, silica sand, silver, sulphur, talc, tantalum, titanium, tungsten, zeolite, zinc and zircon.

And if you noticed that diamonds are missing from that list, they too are covered by a prospecting licence issued two years ago to Australian company Bonaparte Diamond Mines, covering 3393 square kilometres of Golden Bay’s beaches and seafloor stretching all the way down to Kahurangi Point on the West Coast.

That the fabulous level of seafloor minerals controlled by New Zealand are for real was confirmed at last September’s Australasian Institute of Metallurgy and Mining conference in Wellington where Ray Wood of GNS Science and Ian Wright of the UK’s National Oceanography Centre described the value of the resources as being in the untold billions of dollars.

That message seems to have filtered through into the business community, and while the response may be little more than a dribble at the moment, look out for the rush that is bound to follow.