【摘要】 务正道地区铝土矿是由风化作用形成的古风化壳沉积型铝土矿,成矿母岩主要来源于下伏中下志留统韩家店组碎屑岩。文章依据瓦厂坪矿床岩、矿石X衍射、电子探针分析成果,绘制Al2O3-SiO2-FeO三角图,并探讨了风化作用与铝土矿(岩)形成机理,认为风化作用是铝土矿形成的必要条件,母岩风化作用是(一个)Si不断的溶解迁移流失,Al和Ti相对残留、再迁移、沉积富集的过程,铝土矿形成受风化作用时期气候、地理环境等因素影响,矿床规模、矿石质量与风化时间、储藏条件、脱硅富铝作用密切有关。更多还原

【Abstract】 The bauxite deposit in Wuzhengdao area(including Wuchuan,Zheng’an and Daozhen) is sedimentary bauxite deposit of paleo-weathering crust which was formed by weathering.The ore-forming mother rocks are mainly originated from the clasolite of the Hanjiadian formation of underlying middle and lower Silurian system.Based on the findings of ore X-ray diffraction analysis and the electron probe microanalysis(EPMA) on ore bed rock and ore-rock in Wachangping,this paper draws up a triangular diagram of Al2O3-SiO2-FeO and elaborates on weathering and mineralization mechanism of bauxite.The main conclusions have been reached as followings: The essential condition of mineralization of bauxite is weathering.Weathering of mother rock is such a process that Si is continuously dissolved,transported and lost,while Al and Ti are relatively remained,remigrated,settled and enriched.The mineralization of bauxite is affected by factors such as climate and geographical environment during the weathering period.The scale of ore deposit and the quality of ore are closely tied to weathering duration,storage condition,and desilica-allitization.更多还原