黄大松;张霄宇;张国堙;陶春辉;李怀明;

• 1:浙江大学地球科学学院
• 2:国家海洋局第二海洋研究所海底科学重点实验室

摘要(Abstract)：

为了深入了解西南印度洋中脊调查区表层沉积物的物质来源和沉积环境,对大洋第30航次在该区域获取的21个表层沉积物样品进行了物相鉴定和主量元素、微量元素及稀土元素含量测试,分析结果显示,样品可分为Si质沉积物和Ca质沉积物两类,其中Si质沉积物富含Si、Mg、Fe、Al,稀土元素含量特征、轻重稀土元素分馏特征,以及稀土元素的北美页岩归一化曲线均表明沉积物保留了N-MORB的特征,主要为基性岩、超基性岩的风化产物;而Ca质沉积物富Ca、LOI、Sr,稀土元素以及微量元素之间的分配均指示沉积物物源为生源主导;所有站位均显示了两类沉积物不同程度的混杂,表明物质来源具有一定的多样性,调查区总体为稳定的偏氧化环境。

关键词(KeyWords)： 西南印度洋中脊;沉积物;地球化学;物质来源;沉积环境

Abstract:

Keywords:

基金项目(Foundation): 国际海底资源调查与开发“十二五”重大项目(DY125-11-R-05);; 浙江省教育厅项目(Y201430393)

作者(Author): 黄大松;张霄宇;张国堙;陶春辉;李怀明;

Email:

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