Technology to mine deep seabed similar enough to offshore oil development to not present technical barrier
One reason massive-sulphide formations beguile miners is that the metals they contain—notably copper, gold, zinc and silver—are highly concentrated. Another is that they are often big, 200 metres wide and long, tens of metres thick, and may contain several million tonnes of ore. All lie on the surface of the seabed, and many are only 1-2km below water level. At that depth technology developed for the offshore oil industry can nowadays be employed for mining. In particular, the deep-water pumps and suction pipes developed to bring subsea oil up to the surface can be used in the riser pipes needed to bring minerals (mixed with water) up from a massive-sulphide mine. The oil industry has also developed remotely-operated vehicles to make trenches for seabed pipelines, which can be adapted for cutting ore, even though it may lie much deeper, at, say, 1.5km down. In general the technology in the machines needed to carry out deep-water mining is no longer exotic. Woods Hole Oceanographic Institution has a vehicle that can reach depths of 11km.
The technology for deep-sea mining is already widely available, consisting of mining support platform or vessel; a launch and recovery system; a crawler with a mining head, centrifugal pump and vertical transport system; and electrical, control, instrumentation and visualization systems. Companies such as Lockheed Martin, Soil Machine Dynamics, IHC Mining and Bauer or Nautilus Minerals are developing vehicles for deep-sea mining, pledging they are in the position to readily develop techniques to operate down to 5,000 metre depth.