The Mineral Wealth
of the Bismarck Sea; The Oceans; Scientific American Presents; by Binns, Dekker; 6 Page(s)
Last November the government of Papua New Guinea granted a private company permission to prospect for minerals on the floor of the adjacent Bismarck Sea. Other mineral deposits on the bottom of the ocean had drawn attention during the 1960s and 1970s, when people talked about mining zinc-rich oozes two kilometers (1.2 miles) down on the bed of the Red Sea or of harvesting nodules with nickel and copper from five-kilometer-deep abyssal plains in various parts of the world. In more recent years, some have considered mining volcanic seamounts encrusted with oxides thought to contain cobalt and platinum. Yet none of those submarine deposits proved sufficiently valuable to make their extraction worthwhile. So why have the deposits under the Bismarck Sea sparked commercial interest now?
The difference is that the newly found sources of ore on the seabed are massive sulfides, dense minerals rich in copper, zinc, silver and gold. To prospectors, massive sulfides are a familiar prize, because these minerals are often mined on land for their metals. Unlike other deep-sea deposits previously considered for mining, the massive sulfides of the Bismarck Sea occur at relatively shallow depths (less than two kilometers). They also lie in calm waters within an archipelago of Papua New Guinea, which thus owns the right to mine them under international law. These attributes, along with the richness of the deposits, make them much more attractive than any deep-sea mineral prospect ever before contemplated.