铅同位素“双稀释剂”同位素定年法计算方法研究

Research on the Calculating Ways of “Double-Spike” Isotopic Dating Method of Lead Isotope

铅同位素研究已广泛应用于模式定年、成矿物质来源示踪和化探找矿评价等许多领域[1～ 6 ] 。铅同位素“双稀释剂”同位素定年法是当前应用较广的一种铅同位素定年方法。双同位素稀释法的目的在于校正质量鉴别效应 ,提高测定精度。由于实验条件和分析技术的改善和提高 ,使铅同位素“双稀释剂”测定精度和准确度大大提高 ,从而铅同位素“双稀释剂”同位素定年法也将得到更为广泛的应用。本文主要是研究该法的计算 ,分析样品中元素量的计算 ,并结合几种岩石年龄方法 (Pb Pb等时线法、不一致线模式计算法、三阶段模式计算等 )的计算 ,归纳总结出计算样品中元素量和岩石形成年龄的方法。

WT5BZ]Research on lead isotope has been widely applied in many field, such as model dating, ore forming mass source tracing and geochemical explorative prospecting estimate[1-5]. “Double spike” isotopic dating method of lead isotope is one of the dating ways of lead isotope, its aim is to correct mass differentiation effect and enhance the precision of measure. Because experimental condition and analytic technique have been improved, “double spike” isotopic dating method of lead isotope and analyses calculation of element contents. Combinds with several calculating ways of forming ages of rocks (Pb Pb isochron way, inconsistent line model calculating way and three stage model calculating way), a way to calculate element content of samples and forming ages of rocks was summarized. [WT5HZ]