摘要
锆石从晶体中心至边缘的两种成分变化趋势与成因有内在联系。岩浆成因锆石从中心至边缘具有ZrO2含量及ZrO2／HfO2值下降，HfO2和（UO2＋ThO2）含量上升的特征，而变质成因错石则与此相反，本文论述了它们的成因及成因标型意义。
Studies have shown that there are many differences between magmatogenic and metamor-phogenic zircons in chemical composition from the core to the rim, The magmatogenic zircons, ex-hibit composition zonation of increasting HfO2, UO2+ThO2 content and decreasing ZrO2/HfO2 ra-tio and ZrO2 content from the inner to outer portion of each growth zoning or from the core to the edge of a crystal. The metamorphogenic zircons exhibit compositional variation trend opposite to that of magmatogenic zircons, tending to decrease in HfO2, UO2+ThO2 and increase in ZrO2/HfO2 ratio and ZrO, from core to the edge of a crystal. These chemical composition variation trends are considered to be eontrolled by the crystal-chemical features of ions themselves and the evolution trends of magmatism and metamorphism respectively, and can be used to identify the genesis of zircons.
出处
《矿物学报》
CAS
CSCD
北大核心
1995年第4期404-410,共7页
Acta Mineralogica Sinica
基金
国家自然科学基金
关键词
锆石
成因标型
岩浆作用
变质作用
zircon
origin discrimination
magmatism
metamorphism
