摘要
天山地区新元古代—早寒武世玄武质熔岩包括拉斑玄武质和碱性玄武质两个主要岩浆系列,前者是早期(早南华世贝义西组、早震旦世扎摩克提组)喷发的火山岩系的主要组成,后者是晚期(早震旦世苏盖特布拉克组、晚震旦世水泉组、早寒武世西山布拉克组)喷发的火山岩系的主要组成。稀土、微量元素和Sr、Nd同位素特征揭示,这些火山岩均形成于大陆裂谷环境,其源区可能是源于一种似洋岛玄武岩源的软流圈地幔源,并且在岩浆上侵喷发过程中发生了岩石圈的混染。
The Neoproterozoic-Early Cambrian basic lava in Tianshan and its adjacent areas consists of two magma series, namely, tholeiitic and alkaline basaltic magma series. The tholeiitic magma series is the major component part of the early volcanic rocks （Early Nanhua Beiyixi Formation and Early Sinian Zamoketi Formation）, the alkaline basaltic magma series is the main component part of the late volcanic rocks （Early Sinian Sugaitibulake Formation, Neosinian Suiquan Formation and Early Cambrian Xishanbulake Formation）. REE, trace ele- ments and Nd, Sr isotopic compositions reveal that the volcanic rocks were formed in a continental-rift environ- ment, and their source resembled an asthenospheric mantle of ocean-island basalt and was contaminated by geosphere during the upward migration and eruption of the magma.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2006年第5期412-422,共11页
Acta Petrologica et Mineralogica
基金
国家自然科学基金资助项目(40472044)
中国地质调查局综合研究项目(200313000063
1212010611804
200313000028)
关键词
新元古代-早寒武世
火山岩
地球化学
岩石成因
天山
Neoproterozoic-Early Cambrian
volcanic rock, geochemistry, petrogenesis, Tianshan Mountains
