中文摘要：

针对我国锡多金属矿床的定年问题,建立一种采用同位素稀释热电离质谱（ID-TIMS）法进行锡石U-Pb同位素定年的方法,并与激光烧蚀电感耦合等离子体质谱（LA-ICP-MS）法进行对比验证.由于采用化学处理技术分别纯化了U和Pb,减少了普通铅的影响,大大提高了分析测定精度.将该方法应用于某地区石英-锡石-黑钨矿脉的锡石样品分析,获得了精确的U-Pb年龄值.

英文摘要：

Focusing on the problem of the dating of tin polymetallic deposits in China, the authors established a new method for U-Pb isotope dating of cassiterite with isotope dilution-thermal ionization mass spectrometry （ID-TIMS）, and made comparison with laser ablation inductively coupled plasma mass spectrometry. Because U and Pb are purified separately by the new experimental pretreatment technology, the influence of the common lead is reduced, and the analytical precision is greatly improved. This method was applied to the cassiterite samples from a quartz-cassiterite-wolframite vein in a certain area, with a precise U-Pb isotopic age obtained.