【摘要】 粤北大宝山酸性矿山废水(AMD)中形成了呈独特梯田状构造的沉积物,其中的次生矿物可以吸持AMD中的重金属离子,对减少矿山环境的重金属污染有重要意义。本文采集了大宝山AMD中呈梯田状构造中的沉积物,利用多种手段分析了其主要矿物组成以及主要次生矿物的表面形貌特征,探究梯田状沉积物的成因。结果表明,梯田状沉积物的次生矿物以针铁矿、施威特曼石、黄钾铁矾为主,含少量石膏、斜方钙沸石等。针铁矿呈针状、球刺状集合体;施威特曼石呈海胆状、鳞片状,粒度为微米级,海胆状施威特曼石与球刺状针铁矿共生;黄钾铁矾呈不规则的球粒状、片状,与施威特曼石共生。研究表明微生物作用可能是形成铁质梯田状构造的关键因素。更多还原

【Abstract】 Sediment terraces were formed in acid mine drainage( AMD) of the Dabaoshan deposit at north Guangdong province. Secondary minerals in such sediments can absorb heavy metal in AMD and it is of great significance in reducing mine environmental pollution. In this paper,sediment terraces of the Dabaoshan AMD were collected,mineral composition and surface morphology of main secondary minerals were analyzed by using XRF,XRD,SEM-EDS and FTIR,and the origin of terraces was investigated. The results show that the secondary minerals of sediment terraces are mainly goethite,schwertmannite,jarosite,with minor gypsum,gismondine etc. Goethite occurs as needle-like,spiny aggregate. Schwertmannite is urchin-like or scale-like of micron meter scale. The urchin-like schwertmannite is associated with spiny goethite. Jarosite is in irregularly spherical or flaky,associated with schwertmannite. The key factors for the formation of iron terraces may be microbial actions.更多还原