基于石榴石的变质岩年代学

程昊, 徐乃潇

Garnet Geochronology of Metamorphic Rocks

Hao Cheng, Naixiao Xu

图3 榴辉岩中石榴石核部与边部的Lu-Hf等时线呈现明显差异 （a）Trescolmen榴辉岩的全岩—石榴石Lu-Hf等时线， 其中插图为Fe元素成分，据参考文献[62]修改；(b) 大别千斤榴辉岩的石榴石和全岩Lu-Hf等时线图，内部插图显示分离出的2类石榴石具有明显不同的光学特征，据参考文献［63］修改

Fig.3 Garnet cores and rims from eclogites are distinguishable from Lu-Hf isochrons (a) Isochron plots illustrating the different ages obtained for two garnet generations present in an eclogite from Trescolmen, the element map for Fe is also shown，modified after reference[62]; (b) Lu-Hf isochron plot for garnet fraction, bulk rock powder separates of the Qianjin eclogite from the Dabie orogen. Inset photomicrograph shows the separated garnet porphyroblasts with distinct optical contrasts，modified after reference[63]