对白云鄂博矿床U-Pb同位素年代学工作的几点思考

本文主要根据笔者的研究成果,结合近年来文献报道的资料,对白云鄂博矿床U-Pb同位素年代学工作中存在的一些问题,主要是U-Pb同位素定年矿物和定年方法的选择等问题进行讨论,并对U-Pb同位素定年技术在白云鄂博矿床地质研究中的应用潜力进行探讨。笔者的研究成果表明,白云鄂博矿床中适用于U-Pb同位素年龄测定的不同矿物和不同的U-Pb同位素定年技术方法各有不同的特点及局限性。在实际工作中,根据具体的年代学工作要求及从具体样品中分选得到的U-Pb同位素定年矿物的种类及其数量多少、粒度大小、年龄范围、U-Pb含量、测年精度要求等因素,灵活地选择测年矿物及测年方法,加强对定年矿物的成因矿物学研究,结合具体的地质背景对U-Pb同位素定年结果进行合理的地质解释,对于获得比较理想的成果是非常重要的。

Several Thoughts About U-Pb Isotope Geochronology of the Bayan Obo Ore Deposit

The problems of minerals for dating and methods of U-Pb dating about U-Pb isotope geochronology of the Bayan Obo ore deposit are discussed based maily on our studies, combined with references recently reported. The potential prospects of U-Pb dating are studied for applying in geological research of the Bayan Obo ore deposit. The researches show that the different minerals for dating and different methods of U-Pb dating have different characteristics and limitations. It is very important to select minerals for dating and methods of U-Pb dating according to the mineral content, grain size, age range, U-Pb content and dating precision requirement of the samples to get relatively ideal results.