水库渗漏水中氢氧化铁的矿化特征

Mineralization of Iron Hydroxide in Sediments of Seeping Water from Fushui Reservoir

对富水水库大坝渗漏水和析出物进行了分析和研究。析出物的主要成分为Fe2 O3 ,并含少量Al2 O3 和SiO2 。铁质析出物的XRD、IR、SEM和TEM分析表明 ,氢氧化铁的结晶程度较低 ,主要结晶相为针铁矿 ,其次为少量伊利石、蒙脱石和石英。电子显微分析观察到在非晶质氢氧化铁凝胶团和亚微米级微粒聚集体中存在特殊的显微管状和螺旋状针铁矿 ,显示出明显的生物矿化特征。

In this paper, the seeping water and the sediments of the dam base in Fushui Reservoir, whose surrounding strata are mainly Silurian shale, were analyzed and investigated. The sediments are rich in Fe 2O 3 together with small amount of Al 2O 3 and SiO 2. IR, XRD, SEM and TEM analyses show that crystalline minerals in the iron hydroxide sediments are mainly weakly-crystallized goethite with small amounts of illite and montmorillonite. There are some microtubular and spiral goethites scattered among the iron hydroxide colloidal cloud and submicrometer-size colloidal particles. The microtubular walls are found under TEM composed of nano-crystallines of goethite, and microspiral minerals are shown to have a resemblance to Gallionella bacteria in both morphology and size. It is obvious that they are closely related to microorganism mineralization.