韩宗珠,刘涵,李敏,孙晓霞,来志庆,边宇,林学辉

• 1:中国海洋大学海洋地球科学学院
• 2:中国海洋大学海底科学与探测技术教育部重点实验室
• 3:中国地质调查局青岛海洋地质研究所

摘要(Abstract)：

本文对东太平洋海隆赤道地区北部和南部的9件玄武岩样品进行了详细的岩相学和主量、微量元素及Sr-Nd-Pb同位素分析研究,结果表明:MgO含量为7.32%~10.22%,Na_2O为3.03%~3.59%,K_2O为0.23%~0.57%,CaO为10.96%~12.39%,Al_2O_3为11.40%~13.76%,该区玄武岩均属于亚碱性玄武岩,具有MORB型的稀土及微量元素特点,原始岩浆均经历了橄榄石和斜长石的分离结晶。轻重稀土元素含量均较低,LREE/HREE比值为0.61~0.97,(La/Yb)N比值为0.72~1.76,(La/Sm)N比值为0.60~1.30,(Gd/Yb)N为0.99~1.16。Sr-Nd-Pb同位素特征更接近NMORB,其中,87Sr/86Sr和143 Nd/144 Nd比值更接近DM源区,而Pb的三种同位素比值要明显高于DM源区,更为接近EM源区。研究表明岩浆起源于尖晶石橄榄岩区,来源于较为亏损的地幔,NEPR玄武岩可能混有HIMU源区,SEPR玄武岩除了混合有HIMU成分外,可能还有少量的EMⅡ成分。

关键词(KeyWords)： 东太平洋海隆;玄武岩;岩浆作用;结晶分异作用

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目(41376053);; 中国海洋大学国家大学生创新训练项目(201210423030)资助~~

作者(Author): 韩宗珠,刘涵,李敏,孙晓霞,来志庆,边宇,林学辉

DOI: 10.16441/j.cnki.hdxb.20160253

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