Chemical Composition and Genesis of Ferromanganese Crusts from the Sonne Ridge (Kuril Basin, Sea of Okhotsk)

Abstract

Abstract —The paper presents results of a comprehensive study of ferromanganese crusts from a submarine volcano on the Sonne Ridge, which was discovered during the 178th cruise of the RV Sonne (2004) investigating the northern slope of the Kuril basin in the framework of the KOMEX program. Results of study of the structures, textures, and mineral and elemental compositions of the crusts suggest their hydrogenous origin. The contents of major, trace, and rare-earth elements and Y (REY) in four mineral phases of ferromanganese crusts of the Sea of Okhotsk have been determined by phase analysis for the first time. The REY patterns of the manganese and ferrous in-situ phases confirms the hydrogenous genesis and indicates no hydrothermal influence.