锆石中磷的分带趋势、成因及地质意义  

THE PHOSPHORUS ZONATION OF MAGMATOGENIC AND METAMORPHOGENIC ZIRCONS AND THEIR GENESIS AND SIGNIFICANCE IN ORIGIN INTERPRETATION

作　　者：鲍学昭[1] 吴昌华[1] 陆松年[1] 钟长汀[1] 陈志宏[1] 段续川[1] 

机构地区：[1]地矿部天津地质矿产研究所

出　　处：《地质找矿论丛》1996年第1期59-66,共8页Contributions to Geology and Mineral Resources Research

基　　金：国家自然科学基金

摘　　要：本文用电子探针对岩浆和变质重结晶锆石进行了成份分带的研究，结果表明，变质重结晶锆石具有从晶体中心至边缘Ｐ２Ｏ５含量增大的特点，可作为它们的成因标型特征，岩浆锆石则Ｐ２Ｏ５含量变化不稳定，本文论述了它们的成因。The chemical composition, especially the P2O5 zonation of zircons has been studied by electron probe and scan electron microscope photograph, which shows that the metamorphogenic zircons exhibit rounded growth zoning and compositional zonation of increasing P2O5 content, ZrO2/HfO2 ratio and decreasing HfO2 content gradually from core to rim of a crystal, which are considered to be controlled by the temperature and chemical composition variation.trend of their Parent rocks during the metamorphism and can be used to decipher the origin of zircons and their mother rocks. On the other hand, the magmatogenic zircons exhibit euhbedral growth zoning and compositional zonation of decreasing ZrO2/HfO2 ratin and increasing HfO2 content gradually from core to rim of a crystal. This is considered to be controlled by the chemical compositinn and temperature variation trend of magma in it's evolution. But the variation trend of P2O5 content from core to edge of magmatogenic zircons is unstable, which is considered to be affected by the unstable P2O5 content in magma owing to the digestion of P2O5 from surrounding rock and xenolish.

关 键 词：锆石 磷 分带趋势 成因 地质意义 

分 类 号：P578.941[天文地球—矿物学]