北极海域铁锰结核和结壳的分布与成因

对公开发表的有关北极海域铁锰结核和结壳的分布区域、化学成分，矿物类型以及年代学等数据资料进行搜集整理后发现，目前已知的浅水铁锰样品主要分布在喀拉海和楚科奇海域内，而深水铁锰样品主要位于楚科奇海台、加拿大海盆、门捷列夫海岭和阿尔法海岭内。深水铁锰样品主要为水生成因，除Mn外，主要有用金属含量均远高于浅水样品，且多种金属与全球重要结核和结壳成矿带内的样品含量相当，展示出一定的资源潜力。深水铁锰样品生长时间长达1500万a，对应着中新世弗拉姆海峡开启，北冰洋开始与北大西洋进行深水交换时期。浅水铁锰样品主要为成岩成因，周边陆源非金属物质的供给量较大，资源潜力低。

OCCURRENCE AND GENESIS OF THE FERROMANGANESENODULES AND CRUSTS IN THE ARCTIC OCEAN

The distribution, chemistry, mineralogy and chronology of ferromanganese nodules and crusts in the Arctic Ocean are studied in this paper through a thorough review of published papers. There are two types of ferromanganese deposits in the Arctic. The shallow water type of ferromanganese deposits occur in the Kara Sea and Chukchi Sea, while the deep water type located in the Chukchi Plateau, Canada Basin, Mendeleev Ridge and Alpha Ridge. The deep water type is mainly formed by hydrogenetic precipitation. The contents of critical metals in the deep water ferromanganese deposits are much higher than those in the shallow water type except for Mn. The contents of critical metals are comparable with the ferromanganese deposits with great economic potential found in the other parts of world ocean. Therefore, the deep water ferromanganese deposits in the Arctic Ocean are regarded in this paper as a kind of potential resource for these metals. According to the dating data, the deep water ferromanganese deposits in the Arctic Ocean began to form in Miocene about 15 Ma, when the Fram Strait opened up and the deep water exchange initiated between the Arctic Ocean and North Atlantic Ocean. Shallow water ferromanganese deposits are formed by diagenetic process, the excessive supply of terrigenous nonmetallic materials accelerated its growth rate. Therefore, it has a lower potential to be a mineral resource.