摘要
La,Nb ,Zr是一组耐熔强亲岩浆元素 ,其相互之间的比值关系恢复深部作用的地球化学过程。玄武岩类特别是原始玄武岩浆形成的岩石的La/Zr及Nb/Zr比值 ,能较好地反映其源区的La,Nb ,Zr之间的分异特征 ,在一般情况下这一特征与某种确定的大地构造环境有密切关系 ,可用来判别玄武岩类形成的大地构造环境及其源区分异特征。本文根据世界上典型大地构造环境区玄武岩类的La,Nb ,Zr数据 ,划分玄武岩形成的大地构造位置 ,提出了La/Zr-Nb/Zr双对数图及判别方法。
La、Nb、Zr are refractory strong magmatophile elements, during magmatic action, the ratios of La、Nb、Zr could restore processes of mantle partial, magmatic fractional crystallization,mantle fractional and so on. The La/Zr and Nb/Zr ratios of basalts,especially primary one, reflect the differentiation of La、Nb、Zr of its source region.In general,there is a close relationship between these characteristics and tectonic setting, Based on the ratios among La,Nb,Zr of basalts formed from typical tectonic setting of the world ,we propose a new tectonic identification scheme of basalts on the La/Zr and Nb/Zr double logarithmic plot.
出处
《华东地质学院学报》
CAS
2003年第4期343-348,共6页
Journal of East China Geological Institute
基金
四川省地学核技术重点实验室开放基金资助项目 (DH99- 0 1 )
