By: Floro Mercene
Tennis-ball sized nodules are formed over millions of years and present on much of the world’s seabeds. The nodules contain primarily manganese, but also nickel, cobalt and copper, which makes them economically promising. Many thousands of square kilometers of the deep-sea floor are covered by these metal-bearing nodules. They are found in significant abundances in four regions of the ocean.
The world’s largest manganese nodule region is an area of 9 million square kilometers, approximately the size of Europe, Clarion-Clipperton Zone (CCZ) located in the Pacific, extending from the west coast of Mexico to Hawaii. The nodules are not evenly distributed over this area. The total mass of manganese nodules here is calculated to be around 21 billion tons. The Peru Basin lies about 3000 kilometers off the Peruvian coast. It is about half as large as the Clarion-Clipperton Zone. Penrhyn Basin is the third most important manganese nodule area in the Pacific, located near the Cook Islands, a few thousand kilometers east of Australia. So far only a single large area of manganese nodules has been discovered in the Indian Ocean, an area comparable to that of the Penrhyn Basin. It is located in the central Indian Ocean.
Humans began to mine the ocean floor for diamonds, gold, silver, metal ores like manganese nodules and gravel mines in the 1950s. Mining of manganese nodules began in the 1960s.
Together with cobalt crusts, manganese nodules are considered to be the most important deposits of metals and other mineral resources in the sea today. These nodules, contain mainly manganese, as their name suggests, but also iron, nickel, copper, titanium and cobalt. Although many countries and companies are already intensively investigating their distribution, it is not certain whether the manganese nodules will ever be mined. After all, at least for the intermediate future, there are enough metals available on land.
(To be continued)
