Minerals from the ocean

Abstract

Mineral resources are present offshore either as bedrock or superficial Bedrock deposits include petroleum, coal, sulphur, evaporites, and metals. Many of these deposits can be exploited in shallow water using currently-available technology including drilling platforms, solution extraction, and underground mining from onshore installations which extend offshore. Genetically, there are two kinds of superficial deposits; those which formed on the continent but which were subsequently submerged by the post-glacial rise in sea level (lateritic deposits and some types of placer deposits), and those which have formed under submarine conditions at the present time or in the recent past. Deposits of this second group include construction materials, some placer deposits, phosphorites, and glauconite, all of which are found primarily on the shelf and upper slope; and deposits of the deeper oceans, including deep-sea oozes, manganese nodules, and metalliferous muds and brines. Dredging techniques are used for exploiting superficial deposits in shallow waters; various types of dredges are being tested, or are planned for the deeper-water deposits. Although it is probable that many offshore mineral deposits will not be exploited in the near future, they nevertheless constitute long-term resources of considerable importance.