Li-F花岗岩液态分离的同位素地球化学标志  

GEOCHEMICAL INDICATORS OF ISOTOPES IN Li-F GRANIT LIQUID SEGREGATION

作　　者：王联魁[1] 王慧芬[1] 黄智龙[2] 

机构地区：[1]中国科学院广州地球化学研究所,广州510640 [2]中国科学院地球化学研究所,贵阳550002

出　　处：《地质与勘探》2002年第5期38-43,共6页Geology and Exploration

摘　　要：Li-F花岗岩液态分离包括不混溶为主和气液分馏为主两种液态分离作用。Li -F花岗岩不混溶为主液态分离的同位素标志是 :在复式Li-F花岗岩体中 ,随由早至晚阶段Li-F花岗岩侵入变化 ,岩石中δ18O、ISr有先降低后突然升高的变化趋势 ;在典型Li-F花岗岩体中 ,由下部岩相成分相当翁岗岩 (钠长花岗岩 )向上至顶部岩相成分相当香花岭岩 (云英岩、似伟晶岩 )的全岩和石英δ18O突然升高。Li-F花岗岩气液分馏为主液态分离的同位素标志是 :典型Li-F花岗岩体的中、深部岩相向上至浅部岩相 ,岩石有δ18O降低和δD升高的变化趋势。Two kinds of liquid segregation in Li-F granites can be recognised. One is mainly governed by liquid immiscibility and the other by vapour-liquid fractional distillation. The isotopic geochemical indicators of the former are as follow: from early to late stage of the composite Li-F granite mass, δ 18 O and I Sr decrease firstly and then they suddenly increase. And in a typical Li-F granite, from lower rock facies (albite granite), which corresponds to ongonite in composition to the top rock facies(greisen and pegmatoid stockscheider), which corresponds to Xianghualingite in composition, the δ 18 O suddenly increase. The isotopic geochemical indicators of the latter are as follow: from deeper to shallower facies of a typical Li-F granite body, the δ 18 O decrease and δD increase.

关 键 词：Li-F花岗岩 液态不混溶 气液分馏 同位素地球化学 氧同位素 氢同位素 

分 类 号：P588.21[天文地球—岩石学] P597.2[天文地球—地质学]