变质岩等时线定年

Isochron dating of metamorphic rocks

放射性同位素地质年代学是研究地球科学历史的关键钥匙,对于准确厘定地质事件的绝对时间和不同事件之间的联系有着重要意义。其中等时线定年法有着高精度、高准确性的优点,在国际上被广泛应用于变质相关事件的定年,获得其他定年方法所不能替代的年龄信息。变质岩中常用的等时线定年体系主要有Rb-Sr、Sm-Nd、Lu-Hf、Ar-Ar以及Pb-Pb体系,文章主要介绍各等时线体系定年原理,回顾同位素分析技术发展,总结影响等时线定年准确度和精度的因素,展望今后变质岩等时线年代学发展的趋势和突破点。

Radioisotope geochronology is a key to study the history of earth science.It is of great significance for accurately determining the absolute time of geological events and the relationship between different events.Among them,the metamorphic rock isochron dating method has the advantages of high precision and high accuracy.It is widely used in the international dating of metamorphic related events to obtain age information that other dating methods cannot replace.The isochron dating method is widely applied in metamorphic rocks,mainly including Rb-Sr,Sm-Nd,Lu-Hf,Ar-Ar,and Pb-Pb systems.This article describes the dating principles of each radiometric system and reviews recent advances in relevant systems.We summarize the factors that affect the accuracy and precision of isochron dating and illustrate the future trends and potential breakthrough points of isochron dating methods in the future.