Basic Characteristics of Metamorphism of Xinyu Type Iron Ore Field in Jiangxi Province
详细信息
- 责任者：Wang Xiaoying (Ganxi Brigade of Geological Survey ; Jiangxi Bureau of Geology and Mineral Resources ; Nanchang 330030 ; China) ; Zhou Jianting
- 刊名：Resources Survey & Environment
- 出版年：2013
- 卷期：34(3)
- 页码：p.159-164
- issnNo：ISSN1671-4814
- isbnNo：CN32-1640/N
摘要
The Xinyu type ferrosilicine diagenetic metamorphic iron deposit in Jiangxi Province is distributed at the the north margin of Caledonian orogenic belt and in the overthrust metamorphic belt at the southeast margin of Yangtze continental block. This paper studies the characteristics of metamorphism of the iron deposit that have been few dealed with in the previous prospecting, and introduces the deformation features of iron-bearing formation, features of metamorphic rocks of iron-bearing members, interrelation between deformation and metamorphism of the iron-bearing formation and the formation process of iron deposit. It is considered that the primary iron-bearing strata mainly originated from the ancient continental block formed in Jinning period, the flysch sedimentary formation of the rift trough at the active continental margin and submarine volcanic activities also provided part of iron-bearing materials. The iron minerals in the primary iron-bearing members present a phase sequence as specularite-magnetite-siderite-pyrite from below with the variation of rock types, indicating a control by pH and Eh conditions at different water depths during sedimentation caused by variation from oxidation to reducing environment. The iron-bearing members experienced regional metamorphism causing to show four stages of deformation with different intensities and scales, and to produce multiperiodic superimposed folds accompanied by metamorphism, the greenschist facies metamorphism resulted from the low-temperature dynamic metamorphic deformation is most closely related with the iron ore desormation.