西藏革吉地区古近纪碱性火山岩的发现及其地质特征

Early Tertiary Alkaline Volcanic Rocks and Their Geochemical Features in Gê'gyai, Tibet

西藏革吉地区发现的古近纪碱性火山岩为不整合于郎山组之上的一套火山盆地型偏碱性中酸性火山岩及火山碎屑岩,具高硅、富碱高钾、轻稀土富集、铕弱亏损的特点,形成于板内环境。

Early Tertiary alkaline volcanic rocks in Gê'gyai, T ib et consist of Si-rich and K-richalkaline lava and pyroclastic rocks characterize d by enrichment in LREE and slight depletion in Eu.They overplay upon the Langsh an Formation and were formed in an intraplate environment.