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:

DOI:

参考文献(References)：

• [1]Tao C,Lin J,Guo S,et al.First active hydrothermal vents on an ultraslow-spreading center:Southwest Indian Ridge[J].Geology,2012,40(1):47-50.
• [2]王振波,武光海,韩沉花.西南印度洋脊49.6°E热液区热液产物和玄武岩地球化学特征[J].海洋学研究,2014,32(1):64-73.
• [3]韩宗珠,张贺,范德江,等.西南印度洋中脊50°E基性超基性岩石地球化学特征及其成因初探[J].中国海洋大学学报:自然科学版,2012,42(9):69-76.
• [4]陈圆圆,于炳松,苏新,等.西南印度洋中脊钙质沉积物地球化学及矿物学特征[J].地质科技情报,2013,32(1):107-113.
• [5]Dick H J B,Lin J,Schouten H.An ultraslow-spreading class of ocean ridge[J].Nature,2003,426:405-412.
• [6]Tao C H,Li H M,Huang W,et al.Mineralogical and geochemical features of sulfide chimneys from the 49°39′E hydrothermal field on the Southwest Indian Ridge and their geological inferences[J].Chinese Science Bulletin,2011,56(26):2828-2838.
• [7]Yasukawa K,Liu H,Fujinaga K,et al.Geochemistry and mineralogy of REY-rich mud in the eastern Indian Ocean[J].Journal of Asian Earth Sciences,2014,93:25-36.
• [8]Sun S S,McDonough W F.Chemical and isotopic systematics of oceanic basalts:implications for mantle composition and processes[J].Geological Society,London,Special Publications,1989,42(1):313-345.
• [9]黎彤.大洋地壳和大陆地壳的元素丰度[J].大地构造与成矿学,1984,8(1):19-27.
• [10]曹红,曹志敏.西南印度洋中脊海底热液活动[J].海洋地质与第四纪地质,2011,31(1):67-75.
• [11]Fujimoto H,Cannat M,Fujioka K,et al.First submersible investigations of mid-ocean ridges in the Indian Ocean[J].InterRidge News,1999,8(1):22-24.
• [12]Hatch J R,Leventhal J S.Relationship between inferred redox potential of the depositional environment and geochemistry of the Upper Pennsylvanian(Missourian)Stark Shale Member of the Dennis Limestone,Wabaunsee County,Kansas,USA[J].Chemical Geology,1992,99(1):65-82.
• [13]Jones B,Manning D A C.Comparison of geochemical indices used for the interpretation of palaeoredox conditions in ancient mudstones[J].Chemical Geology,1994,111(1):111-129.
• [14]王淑芳,董大忠,王玉满,等.四川盆地南部志留系龙马溪组富有机质页岩沉积环境的元素地球化学判别指标[J].海相油气地质,2014,19(3):27-34.
• [15]Hu Y,Feng D,Peckmann J,et al.New insights into cerium anomalies and mechanisms of trace metal enrichment in authigenic carbonate from hydrocarbon seeps[J].Chemical Geology,2014,381:55-66.
• [16]Feng D,Chen D,Peckmann J,et al.Authigenic carbonates from methane seeps of the northern Congo fan:Microbial formation mechanism[J].Marine and Petroleum Geology,2010,27(4):748-756.
• [17]Fitzgerald C E,Gillis K M.Hydrothermal manganese oxide deposits from Baby Bare seamount in the Northeast Pacific Ocean[J].Marine Geology,2006,225(1):145-156.
• [18]Hein J R,Mizell K,Koschinsky A,et al.Deep-ocean mineral deposits as a source of critical metals for high-and green-technology applications:Comparison with land-based resources[J].Ore Geology Reviews,2013,51(2):1-14.
• [19]Zhou H,Dick H J B.Thin crust as evidence for depleted mantle supporting the Marion Rise[J].Nature,2013,494:195-200.
• [20]张涛,林间,高金耀.90 Ma以来热点与西南印度洋中脊的交互作用:海台与板内海山的形成[J].中国科学:D辑,2011,41(6):760-772.