东太平洋海隆13°N附近沉积物中的热液活动记录

IOCAS-IR > 海洋环流与波动重点实验室

	东太平洋海隆13°N附近沉积物中的热液活动记录
其他题名	The hydrothermal activity records in sediments from East Pacific Rise 13°N
	李康
学位类型	博士
	2009-05-27
学位授予单位	中国科学院海洋研究所
学位授予地点	海洋研究所
关键词	沉积物岩芯元素存在形式热液活动记录东太平洋海隆13&Ordm n
摘要	本文以东太平洋海隆13ºN附近E53沉积物岩芯为研究对象，进行了矿物学、全岩化学分析及连续提取分析，探讨了沉积物中的热液活动记录及元素存在形式，并结合已有的测年数据，对研究区域的热液活动过程进行了初步讨论。 E53岩芯分为三层，上层为红褐色沉积层，中层为棕黄色沉积层，下层为灰绿色沉积层。沉积物岩芯的X射线衍射结果显示，E53岩芯上层非晶质的铁锰氧化物含量较高，中下段方解石含量较高。根据元素在岩芯全岩及各相态间的存在状况，将常量及微量元素分组讨论。Fe、Mn元素以铁锰氧化物相为最重要的赋存相，且与全岩样品一致，呈现随深度下降趋势。Al、Ti、Ba主要存在于残留相中；K、Na、Mg主要赋存相为碳酸盐相；Ca、Sr同样主要存在于碳酸盐相中。微量元素Mo、Co、V、Cu、Zn、Ni、Y和Pb元素主要存在于铁锰氧化物相，且含量均随深度增加而下降。Th、Sc、Li和Zr的主要存在于残留相中；Cd、U主要存在于碳酸盐相中。稀土元素存在形式有以下三个特点：1、主要存在于铁锰氧化物相中，并且呈现出随深度增加含量下降的趋势；2、次要存在形式为碳酸盐相，随深度增加含量上升并一度超过残留相中的含量；3、在有机结合相和残留相中含量很低，且变化幅度不大。根据本文讨论结果，结合前人年代数据，认为E53岩芯中记录的为程度逐步加强且在近期保持稳定的热液活动。
其他摘要	We have carried out XRD analyses, sequential extraction procedures and whole-rock analyses for the sediment samples obtained from E53 site near the East Pacific Rise 13º N. We discussed hydrothermal activity records in sediment core according to the mode of occurrence of elements and the process of hydrothermal activity in study area combining with dating data. The sediment core can be divided into three layers, with the upper layer brown, the middle layer yellow and the bottom layer sage green. The XRD results indicate that the primary mineral phase of E53 upper layer is amorphous Fe-oxyhydroxide and Mn-oxides and the main mineral phase of its bottom layer is calcite. According to elements in whole-rock and different phases, we divide major and trace elements into different groups. Fe and Mn mainly concentrate in the ferromanganese oxide phase，and their contents decrease according with whole-rock samples downcore. Al、Ti、Ba mainly concentrate in the residual phase and K、Na、Mg mainly concentrate in the carbonate phase. Ca、Sr also mainly concentrate in the carbonate phase, which have carbonate as their main modes of occurrence. When coming to trace elements, Mo、Co、V、Cu、Zn、Ni、Y、Pb mainly concentrate in ferromanganese oxide and decrease in contents with depth. Th、Sc、Li、Zr mainly concentrate in the residual phase; Cd、U mainly concentrate in the carbonate phase. There are following three characters in mode of occurrence of elements of rare earth elements (REE). Firstly, REEs mostly concentrate in the ferromanganese oxide phase and the contents decrease downcore. Secondly, the secondary modes of occurrence is the carbonate phase, the contents increase downcore and exceed the former at one time. Thirdly, contents are very low and vary little in the redisual phase and the bound to organic phase. Combining with former dating data, we could conclude that the records in E53 sediment core reflect a recent hydrothermal activity which were enhaced but stable recently.
页数	77
语种	中文
文献类型	学位论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/1377
专题	海洋环流与波动重点实验室
推荐引用方式 GB/T 7714	李康. 东太平洋海隆13°N附近沉积物中的热液活动记录[D]. 海洋研究所. 中国科学院海洋研究所,2009.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
10001_20062800681205（4917KB）			限制开放	--	浏览