1976/05/01 by S V Margolis, Stanley V. Margolis, R G Burns +1
Earth and Planetary Sciences · #Geochemistry and Elemental Analysis
paper · doi:10.1146/annurev.ea.04.050176.001305
Since their first recovery from the ocean floor in the 1 870s during the cruises of the H.M.S. Challenger (Murray & Renard 1 891 ), manganese nodules have been found to cover vast portions of the bottoms of the Pacific, Atlantic, and Indian oceans. Despite an enormous amount of research during the ensuing 100 years, the genesis of these deposits remains an enigma. For decades deep-sea manganese nodules were only a scientific curiosity, but economic and political attention has recently been focused on them. In the northeastern equatorial Pacific (Figure I) they have been shown to exhibit copper and nickel concentrations of around 3 wt% and seafloor surface coverages with potential for mineral resource exploitation (Ham mond 1974a,b). In response to this economic impetus, the international scientific community has launched major research programs during the last three years. Many of the tech nological leaders, including the -United States, Germany, Japan, France, New Zealand, and the USSR, have conducted one or more major scientific cruises to the central Pacific to map the distribution of nodules in relation to seafloor geological features and to recover nodule samples for analysis. In the United States, the princi pal scientific effort on manganese nodules has been the work of the Manganese Nodule Project, funded by the Seabed Assessment Program of the International Decade of Oceanographic Exploration Division (IDOE) of the National Science Foundation (NSF). This project focuses on ferromanganese deposits that are or may be considered potential mineral resources, that is, that contain sufficiently high