Mineral and chemical compositions of authigenic carbonates from the northern Deryugin Basin, Sea of Okhotsk

Mineral and chemical compositions of authigenic carbonates are studied by several methods in a sediment core collected in the axial zone of the Deryugin riftogenic basin. Manganese carbonates (kutnahorite, rhodochrosite) associated with manganiferous calcite, manganiferous pyrite, and nontronite are firstly identified in the Sea of Okhotsk. Manganese carbonates in Holocene diatomaceous ooze were presumably formed due to diagenetic transformation of sedimentary manganese hydroxides, organic matter, and biogenic silica, while those found in the underlying turbidites precipitated owing to the intermittent influx of endogenic fluids migrating along sand interbeds.