Mining at the bottom of the sea: Opportunities and uncertainties

At the beginning of July, the International Seabed Administration (ISA) received a dossier from China asking for permission to exploit the seabed sulphide mines in the international waters of southwestern Indian Ocean.

The race to control the vast mineral resources in the ocean is once again heated .

Treasure under the sea

For researchers, the black chimney is one of the most exciting geological phenomena on the ocean floor. In essence, this is a form of hydrothermal vents (cracks in the earth's crust, creating an eruptive water stream heated by geothermal). Seawater penetrates through porous rock layers, encountering hot lava flows of underground volcanoes, boiled to over 4000 degrees C, then pushed back, bringing a lot of precious minerals in soluble form. When it comes to the cold water above, these minerals precipitate, forming dark columns of water, which can be as high as 60 meters, at first glance like a giant column of smoke. Black chimneys are usually made of sulphide-rich water.

Besides, another term is used for white chimneys to indicate hydrothermal vents containing lighter colored minerals such as barium, calcium and silicon. Over time, minerals settle down, forming ore sieves. That is where one can find most of the raw materials needed for industries. A preliminary study showed that only coastal waters of Papua New Guinea, New Zealand, Indonesia and Japan had nearly 200 black chimneys. Many of them have reserves of 5-10 million tons of ore, enough to attract mining companies.

Ships serving Nautilus seabed exploration and mining.

Race in the 'underworld'

Twenty years ago, even the most imaginative people dared not think of mining at depths of more than 2,000 meters below sea level. But with the current technological achievements, it is entirely feasible. In fact, the oil and gas industry has been able to drill 1,500 meters deep on the Brazilian continental shelf and is deploying deep drills up to 2,500 meters in the Gulf of Mexico. Modern equipment used in oil and gas exploration and exploitation will be an important premise to deploy mining projects. In addition, the perfection of the satellite navigation system also contributes to simplifying the location of black chimneys and white chimneys.

The first comprehensive project to search for undersea mineral resources is hosted by Nautilus, a Canadian-based company. Nautilus is negotiating to gain commercial exploitation rights for a nearly 60km ² seabed area located at a depth of 1,600m off Papua New Guinea. If conditions permit, the project will commence operations in 2011. Exploration drilling results show that the area has a large amount of mineral reserves, especially gold and copper, estimated to reach total value. At least 1 billion dollars at current prices. Another interesting fact is that the ratio of copper in ore here is 8-10%, while on the ground mines, this figure only averages 0.59%. Thus, for every ton of copper collected from the seabed, the volume of matter that the operator must handle is 40% lower.

The most successful business in the search for profits from the seabed is probably De Beers, which is holding 40% of the world diamond market. As one of the pioneers in shifting from mining onshore to ocean bottom exploitation, De Beers is also the first company to develop a technology suitable for digging and collecting. Collect diamond ores at a depth of 150m below the water surface. The De Beers project deployed in the porous sediments off Namibia for a staggering effect: diamond production by 47 operators is equivalent to the output of a mine using 3,300 employees. on land. In 2006, only in this seabed, the company obtained 1,018 million carats of rough diamonds with a total value of $ 350 million.

The huge demand of hot-growing industries such as China and India has pushed mineral prices continuously to new heights. At the beginning of the project off Papua New Guinea, Nautilus said it would earn interest as long as the copper price was above $ 1.5 a pound. Meanwhile, copper prices are now at $ 3.2 per pound and promise to continue to rise as demand is still very high, while ground mines have been exhausted.

A black chimney at the bottom of the sea

This is also the general situation of many other minerals such as gold, silver, nickel . It is easy to understand why mining companies are so enthusiastic in implementing seabed exploration projects. In this context, Chinese records sent to ISA are especially noted. This is the first application for permission to exploit seabed minerals in international waters (projects such as De Beers or Nautilus are carried out in waters under the sovereignty of nations, given by the country itself. permission based on mutual benefit sharing agreement. China's success (in the case of its approved records) could usher in a new era in the race to control mineral resources in the ocean, by the way, many hydrothermal vents has been identified in international waters.

Environmental worries

Another reason that public opinion, especially environmental organizations interested in Chinese records is because it was made at the right time when the historic oil spill in the Gulf of Mexico was at its worst. Many environmental activists are concerned that undersea mining could also lead to a similar disaster, especially when its impact on the sustainability of the seabed and ecosystems stratum The situation around the mining area has not been fully studied.

Representatives of mining companies claim that undersea mining is less harmful to the environment than onshore mining. Deploying an offshore fishing site does not have to relieve the population, nor does it affect the landscape. Due to the characteristics of the ore mined from the seabed, the amount of chemicals required in the treatment process will be less. The risk of acid pollution is almost unlikely because acid will be neutralized in alkaline seawater.

However, these views do not make organizations feel at ease. The first concern is dust clouds that form and expand along the ocean currents when the seabed sediment is scratched. Mining companies affirmed their technology to ensure this problem does not occur. But according to environmentalists, a number of survey activities in the past have caused bottom-level organisms around hydrothermal vents to lose their habitat. Among these, there are many strange life forms that are not available anywhere else on earth. Researchers are concerned that undiscovered undersea mining may cause many species to disappear before being known.

Source: AP, Independent, Spiegel