分离的大陆板块边缘镁铁-超镁铁岩系Th/Hf-Ta/Hf判别

Th/Hf-Ta/Hf IDENTIFICATION OF MAFIC AND ULTRAMAFIC ROCKSERIES IN THE MARGIN OF SEPARATED CONTINENTAL PLATE

本文在论述了 Th/ Hf— Ta/ Hf关系判别岩浆岩源区大地构造环境机理的基础上 ,根据世界上典型大地构造环境区岩浆岩系的 Th、Ta、Hf特征 ,提出了分离的大陆板块边缘镁铁 -超镁铁岩的 Th/ Hf— Ta/ Hf判别标志 :Th/ Ta=1.8～ 4 .0 ,Ta/ Hf>0 .

This paper proposes the mechanism identifing tectonic setting of source region ofigneous rocks by Th/Hf and Ta/Hf ratins.Based on the characteristics of Th, Ta and Hf ofigneous rock series in typic tectonic setting,we propose the identification Index of mafic andultramafic roek series in the margin of separated continental plate by Th/Hf and Ta/Hf:Th /Ta=1.8-4.0,Ta/Hf>0.1.