Ferruginous Microspherules in Bauxite at Maochang, Guizhou Province, China: Products of Microbe-Pyrite Interaction?  

作　　者：ZHOU Yuefei WANG Rucheng LU Jianjun LI Yiliang 

机构地区：[1]State Key Laboratory for Mineral Deposits Research, Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu 210093, China [2]Astrobiology Group, Center for Environmental Biotechnology, 10515 Research Drive Suite 300, Knoxville, TN 37932 USA

出　　处：《Acta Geologica Sinica(English Edition)》2006年第4期604-609,共6页地质学报（英文版）

摘　　要：The Maochang bauxite in Guizhou Province is one of the important aluminum ore deposits in southwestern China. Ferruginous spherules, measuring about a few microns across, were found in the transitional layer of the deposit. The EDS and XRD results show that the microspherules are composed mostly of iron （hydr）oxide minerals （goethite） with only weak presence of aluminum and silicon. Occasionally, some pyrite micrograins with dissolved surface are found associated with goethite within the spherules. It is thus suggested that microspherules are linked to pyrite oxidization. It is also thought that microbial activities contribute not only to pyrite oxidization, but also to ball-like assemblage of the iron （hydr）oxides. The mechanism of the formation of ferruginous microspherules is also believed to be important in studying geomicrobiology of bauxite.The Maochang bauxite in Guizhou Province is one of the important aluminum ore deposits in southwestern China. Ferruginous spherules, measuring about a few microns across, were found in the transitional layer of the deposit. The EDS and XRD results show that the microspherules are composed mostly of iron （hydr）oxide minerals （goethite） with only weak presence of aluminum and silicon. Occasionally, some pyrite micrograins with dissolved surface are found associated with goethite within the spherules. It is thus suggested that microspherules are linked to pyrite oxidization. It is also thought that microbial activities contribute not only to pyrite oxidization, but also to ball-like assemblage of the iron （hydr）oxides. The mechanism of the formation of ferruginous microspherules is also believed to be important in studying geomicrobiology of bauxite.

关 键 词：BAUXITE ferruginous microspherules microbe-pyrite interaction Maochang GUIZHOU 

分 类 号：P578.292[天文地球—矿物学]