Noble, Rare-Earth, and Nonferrous Metals in Ferromanganese Crusts from Submarine Volcanoes of the Sea of Japan

摘要

Ferromanganese crusts from 1 mm to 20 cm thick were recovered in the course of dredging the slopes of submarine volcanoes in the Sea of Japan in the first expeditions carried out by the Department of Marine Expeditions of the Il'ichev Pacific Oceanological Institute. Judging by the content of main ore elements, these crusts differ from crusts of the northwestern Pacific in a high Mn content and an anomalously low Fe content. The Mn content in them varies within 20-40%, and the Fe content varies from 1 to 8%. No clear regularity between the Fe and Mn contents has been revealed. It is worth noting that crusts with higher Mn content are characteristic of the Central Basin.