南海的铁锰结核

Fe-Mn NODULES IN THE SOUTH CHINA SEA

本文从铁锰结核的形态、产状和分布、结构和构造及物质组成等,探讨南海铁锰结核成因问题。初步认为:铁锰结核的沉积环境是下陆坡和深海盆区,主要物质来源是外洋海水和深海区海底火山物质,且以胶体化学成因为主。最后提出铁锰结核的远景评价及古今对比问题。

The present study deals with Fe-Mn nodules in the aspects of form, occurence, distribution, configuration, structure, composition and origin. With different forms of the nuclear materials, the nodules are shown in a variety of forms which can be summed up into 6 categories. While classification according to s racial morphological parameters divides them mostly into the r-group nodules with rough surface and the buried type that buries in sediments. The nodules are usually concentrated at the lower edge of a gentle continental slope, or in brown clay and siliceous ooze in the deep sea basin. They have girdle texture of rough laminated structure, colloid form girdle texture and crypto-laminated crustal texture. Generally, a nodule consists of 2 parts, namely, crust and nucleus. Crustal minerals are 10A manganite, 7A manganite and 8MnO2; and in the nucleus, dolomite, pyrite and argillaceous detritus containing foraminifera are commonly seen. Chemical components of the nodules are mainly Mn, Fe, Cu, Co, Ni, V and Ti; among them, Fe accounts for a high proportion; the ratio of Mn:Fe is usually less the 1; contents of Co, Cu, Ni and Ti are relatively stable, which (except that of Ti) are equivalent to those in the world oceans.Fe-Mn nodules are mainly of colloform chemical origin and deposited in deep sea basin environments, with chief material sources of volcanic matter from seawater of oceans and from sea floor of the deep sea basin. In the region, conditions are favourable for generating and concentrating Fe-Mn nodules. A preliminary study on their concentration, prospects and comparison to old deposits has been made.