老挝波罗芬高原铝土矿地质特征与成矿规律

Geological characteristics and mineralization regularity of bauxite in Boloven Plateau Laos

老挝南部占巴赛省波罗芬高原分布大面积玄武岩,红土化作用强烈。通过野外地质调查、浅井施工,结合样品化学分析、X射线衍射、X射线荧光、等离子质谱等分析方法,对老挝波罗芬高原的铝土矿地质特征与成矿规律进行研究。研究结果表明:老挝波罗芬高原存在丰富的铝土矿,该铝土矿是由玄武岩风化而成,分布于整个波罗芬高原及周边地区,Al2O3含量为30%～50%,Fe2O3含量为25%～40%,铝硅比为5～20,具有中铝、高铁、低硅与高铝硅比,分布范围广,资源量巨大,覆盖浅,地势平缓等特点,适合于大型机械化露天开采,是一个红土型风化壳型三水铝土矿巨型矿带。

There is a large-area basalt in the Boloven Plateau Champasak Province, South Laos and intense laterization. Through the methods of field geologic research, exploring shaft, sample chemical analysis, X-ray diffraction, X-ray fluorescence, inductively coupled plasma-mass spectrum （ICP-MS） and so on, the geological characteristic and mineralization regularity of the bauxite were studied. The results show that there is abundant lateritic gibbsite, which is weathered from basalt and distributed in the whole Boloven Plateau and neighbor. A1203 content is 30%-50%, Fe203 content is 25%-40%, and the ratio oral to Si is 5-20. It has a characteristic of middle Al, high Fe, low Si, high ratio of Al to Si, wide extension, large reserves, little overlay, fiat terrain and so on. It is a huge lateritic bauxite deposit and is fit for large-scale mechanized opencast working.