摘要
利用电子显微术,研究太平洋中部多金属结核中的锰矿物。主要锰矿物为水羟锰矿和钡镁锰矿,它们显示不同的电子衍射花样特征和形貌特征。钡镁锰矿根据形态特征分为三个相:纤维状、片状和板条状。水羟锰矿和钡镁锰矿都是自生矿物,水羟锰矿主要是通过微生物氧化直接从溶液中沉淀生成。而钡镁锰矿则是在没有微生物参加下由溶液中分离出来的。两种矿物之间有着密切的生长关系。
The mineral samples were collected in the Northern Equatorial Pacific Ocean. They are composed of multi-metallic nodules and micro-nodules. The electron microscopic study, mainly selected area electron diffraction, was applied to the specimen for precise identification of Mn minerals.The Mn minerals of the multi-metallic nodules are microcrystals usually in the form of multi-phase intergrowths of Mn oxides. In order to precisely identify the structure and components of the minerals, electron microscopy, including the diffraction contrast image, selected area electron diffraction and energy dispersive X-ray analysis, was applied to the nodules. On the basis of the results of laboratory studies, especially those of the characteristics of the electron diffraction patterns, the principal Mn minerals were determined as vernadite and todorokite. Todorokite may be fibrous, lamellar or elongated lamellar.While vernadite was precipitated directly as an authigenic mineral from the relevant solution by the oxidation of Mn^(2+) to Mn^(4+) through the catalysis of micro-organisms, todorokite was separated from the solution chemically without the help of microbe. Some lamellar todorokite is morphologically and structurally similar to part of the related characteristics of vernadite and hence these two minerals were genetically closely related.Fine mixtures of vernadite and cryptomelane were observed in the sample.
出处
《地质学报》
EI
CAS
CSCD
北大核心
1992年第3期219-226,共8页
Acta Geologica Sinica
关键词
太平洋
多金属
结核
锰矿
电镜
electronmicroscope, multi-metallic nodules, vernadite, todorokite
