摘要
利用电感耦合等离子体原子发射光谱仪(ICP-AES)和重量法,对麦哲伦海山链西北端M海山9个站位、17个富钴结壳样品的主要元素和稀土元素进行了分析,分析结果显示,该海山富钴结壳是水成成因的,且多数富钴结壳在生长过程中没有受到磷酸盐化作用的影响。推广富钴结壳Co地层学年代计算公式的应用范围,并基于此建立了研究区富钴结壳的年代学框架。研究区富钴结壳的Co地层学年代计算公式的计算结果显示,中新世以来的地质时代是M海山富钴结壳的主成矿期,并且大约在15Ma发生了一次磷酸盐化事件,推测当时导致磷酸盐化发生的最低含氧带(OMZ)的深度下降到相当于现今2 000～2 700m水深之间。
17 Co-rich ferromanganese crusts from 9 sites at the Seamount M in the northwest of Magellan Seamounts were investigated geochemically with inductively coupled plasma atomic emission spectroscopy （ICP AES） and weight method. Geochemical composition of those samples suggests that those Co-rich Fe- Mn crusts are hydrogenetic in origin and most of them were not phosphatized during formation. This paper extends the usage of Co chronology to bulk samples. The ages dated by the Co chronology suggest that those Co-rich Fe-Mn crusts mainly formed since Miocene, and one of them were phosphatized around 15 Ma when the oxygen minimum zone （OMZ）, where the Co rich Fe Mn crust formed, immerged to the present water depth of 2 000-2 700 m.
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
2011年第6期65-74,共10页
Marine Geology & Quaternary Geology
基金
海洋公益性行业科研专项(201005003)
科技部国际科技合作重大项目(2006DFB21620)
国家自然科学基金项目(40806027)
国际海底区域研究开发“十一五”课题(DYXM-115-01-2-1)
国家海洋局第一海洋研究所基本科研业务费专项资金项目(2008T03,GY02-2009G23)
“泰山学者”建设工程专项经费
关键词
富钴结壳
矿床成因
成矿时代
麦哲伦海山群
Co-rich ferromanganese crust metallogeny ore-forming epoch Magellan Seamounts
