Cobalt-rich crust obtains high contents of key elements from seawater: element absorption and distribution

Cobalt-rich crust is formed from precipitation of dissolved elements in low temperature seawater on the slope of seamounts.It is widely distributed on the slope of seamounts and undersea plateau in the oceans, with huge reserves.Ferromanganese crusts have high contents of Co, Ni, Pt, REE, Te, which reach 10⁵-10¹⁰ times of the seawater.They are important sources of new energy and high-tech elements in the future and have great potential economic value.The former researchers have focused on the association and enrichment mechanism of the elements in the cobalt-rich crust, with the help of step leaching, absorption experiment, modern ocean observation, water chemistry, high resolution of fine mineralogy.It reveals that cobalt-rich crusts are mainly composed of ferruginous vernadite and amorphous Iron hydroxide.In the process of marine chemistry near seamounts, ferrugvnous vernadite colloid and iron hydroxide colloid preferentially adsorb Co, Ni, Pt, REE and Cu, Pb, Te, REE, respectively.Surface oxidation/lattice replacement result in the continuous accumulation of Co, Pt, Ni, Ce in ferrugvnous Vernadite and Te, Ce in iron hydroxide.The extremely slow growth rate (1~10 mm/Ma), ultra-high porosity (60%) and large surface area (300 m²/g) of cobalt-rich crusts all promote the high enrichment of key elements in the crusts.The trace elements enrichment mechanism of the cobalt-rich crust is key to paleo-oceanography inversion.On the other way, the factors controlling the geochemical differences of cobalt-rich crust in the ocean need further study, understanding which will contribute to the exploration of cobalt-rich crust resources.