Studies are undertaken to characterize the uranium and thorium minerals of south-east Madagascar. Seven selected uranothorianite bearing pyroxenites samples from old abandoned uranium quarries in Tranomaro, south Ambo...Studies are undertaken to characterize the uranium and thorium minerals of south-east Madagascar. Seven selected uranothorianite bearing pyroxenites samples from old abandoned uranium quarries in Tranomaro, south Amboasary, Madagascar (46°28'00"E, 24°36'00"S) have been collected. To determine the mineral micro-structure, they were investigated for qualitative identification of crystalline compounds by using X-ray powder diffraction analytical method (XRD). Results showed that the uranium and thorium compounds, as minor elements, were present in various crystalline structures. Thorium, as thorianite, is present in a simple ThO2 cubic crystalline system, whereas the uranium component of the Tranomaro uranothorianite samples is oxide-based and is a mixture of complex oxidation states and crys-talline systems. Generally called uraninite, its oxide compounds are present in more than eight phases.展开更多
基金This paper was completed within the framework of a cooperation between the Institut National des Sciences et Techniques Nucléaires(Madagascar-INSTN)the Institute of Nuclear Waste and Disposal(INE)The German Academic Exchange Service(Deutscher Akade-mischer Austausch Dienst:DAAD)financed a fellowship.
文摘Studies are undertaken to characterize the uranium and thorium minerals of south-east Madagascar. Seven selected uranothorianite bearing pyroxenites samples from old abandoned uranium quarries in Tranomaro, south Amboasary, Madagascar (46°28'00"E, 24°36'00"S) have been collected. To determine the mineral micro-structure, they were investigated for qualitative identification of crystalline compounds by using X-ray powder diffraction analytical method (XRD). Results showed that the uranium and thorium compounds, as minor elements, were present in various crystalline structures. Thorium, as thorianite, is present in a simple ThO2 cubic crystalline system, whereas the uranium component of the Tranomaro uranothorianite samples is oxide-based and is a mixture of complex oxidation states and crys-talline systems. Generally called uraninite, its oxide compounds are present in more than eight phases.
