辽西义县旋回火山岩的稀土元素特征
Rare earth element characteristics of volcanic rocks from Yixian formation of Western Liaoning
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摘要: 义县火山旋回可分为4个亚旋回。从早期至晚期,义县旋回火山岩逐渐由基性向中基性、中性和酸性演化。义县旋回火山岩稀土总量较高,稀土分布模式呈右倾型,轻稀土分馏作用高于重稀土的分馏作用,为轻稀土富集型,总体显示弱负铕异常、弱的正铈异常。稀土元素具有陆内火山岩的基本特征。成因分析表明:义县旋回火山岩的形成,受地幔热流和壳幔物质的再循环制约,火山岩的成因以部分熔融为主。Abstract: Volcanic rocks of mesozoic were widely distributed in Western Liaoning province.Yixian volcanic Cycle of early Cretaceous is divided into four subcycles.From early to late, the magma of Yixian volcanic cycle evolved gradually from basic, inter mediate-basic and intermediate to acidic.The ∑REE of volcanic rocks of Yixian volcanic cycle is high and rich in LREE.The spider patterns are the right-incline and there is a slight low Eunegative abnormality and low Ce postive abnormality.REE characteristics show that volcanic rocks of Yixian volcanic cycle were generated in responsing to lithosphere extension in the continent intraplate orogenic belt.The lithogenesis take partial melting as a major part.
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Key words:
- Yixian volcanic cycle /
- volcanic rocks /
- rare earth elements /
- partial melting
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曹丛周.辽西地区侏罗纪火山岩特征[J].中国地质科学院沈阳地质矿产研究所所刊,1982,(3):47-54.
王国帧.辽西中生代火山岩岩石化学特征及生成构造环境的分析[J].辽宁区域地质,1980,(2):1-12.
张招崇,李兆鼐,王富宝,等.辽西义县盆地火山岩的基本特征及其成因探讨[J].现代地质,1994,8(4):441-451.
郭洪中,张招祟.辽宁西部中生代火山岩的基本特征[J].岩石矿物学杂志,1992,(3):193-204.
陈义贤,陈文寄,等.辽西及邻区中生代火山岩-年代学、地球化学和构造背景[M].北京:地震出版社,1997.
李伍平,李献华,路凤香,等.辽西早白垩世义县组火山岩的地质特征及其构造背景[J],岩石学报,2002,18(2):193-204.
张立东,郭胜哲,张长捷,等.辽宁西部义县组湖相枕状熔岩的发现及其意义[J].地球学报,2002,6:491-494.
陈德潜,陈刚.使用稀土元素地球化学[M].北京:冶金工业出版社,1990.
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