First Comprehensive Sampling of the Shona and Discovery Seamount Chains, South Atlantic - Plume Versus Shallow Sources

对南大西洋绍纳海山链和发现海山链的首次全面采样 - 羽流与浅源

• 批准号: 0738437
• 负责人: Cornelia Class
• 金额: $ 26.99万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0738437&HistoricalAwards=false
• 关键词: First; Comprehensive; Sampling; Shona; Discovery

ABSTRACT - 07518437 (Class)Intellectual Merit: This research is part of a larger international collaboration to examine geological and geophysical phenomena of the seafloor and the phenomena beneath it in the South Atlantic in the area of the Shona and Discovery hotspots. Although the existence of Shona and Discovery mantle plumes has been suggested based solely on geochemical signatures measured in Mid-Ocean Ridge basalts, the verification of one or more mantle plumes has yet to be made. The presence of these are important because they form the basis of models of continental alkaline magmatism such as the South African diamond-bearing kimberlites and for the recycling and dispersal of subcontinental lithospheric mantle. Research will focus on the analysis of samples from dredged from the German Polarstern cruise to the Shona Ridge - Agulhas Ridge - Cape Rise and Discovery Seamount areas in the South Atlantic. The funded work will entail analyses of seafloor volcanic rocks for Sr-Nd-Hf-Pb isotopic compositions. These data will be integrated with major and trace element data and geophysical data from a multidisciplinary, international team of investigators. The integrated data set will be used to determine the existence of a long-lived Shona plume or, alternatively, a continental origin for the Shona and Discovery bathymetric anomalies. Broader impacts: Impacts of this work include international cross-disciplinary collaboration with Germany, The Netherlands, and South Africa. It will support a female career researcher and help train a graduate student from the University of Cape Town who will be trained in analytical methods and conduction of independent research. Funding also will help provide essential equipment to the isotope lab at Lamont Doherty Earth Observatory.

摘要-07518437(等级)智力价值：这项研究是一个更大的国际合作的一部分，该合作旨在研究南大西洋肖纳和发现号热点地区的海底地质和地球物理现象及其下面的现象。尽管仅根据在大洋中脊玄武岩中测量到的地球化学特征就提出了Shona和Discovery地幔热柱的存在，但还没有对一个或多个地幔热柱进行验证。它们的存在是重要的，因为它们构成了大陆碱性岩浆作用模式的基础，如南非含钻石金伯利岩，以及次大陆岩石圈地幔的循环和扩散。研究将侧重于分析从德国Polarstein邮轮到南大西洋Shona Ridge-Agulhas Ridge-好望角隆起和Discovery海山地区的疏浚样本。所资助的工作将需要对海底火山岩进行锶-钕-氢-铅同位素组成的分析。这些数据将与一个多学科的国际调查小组提供的主要和微量元素数据以及地球物理数据相结合。综合数据集将被用来确定是否存在长寿的肖纳烟柱，或者，作为替代，确定肖纳和发现号水深异常的大陆起源。更广泛的影响：这项工作的影响包括与德国、荷兰和南非的国际跨学科合作。它将支持一名女性职业研究人员，并帮助培训开普敦大学的一名研究生，他们将接受分析方法和进行独立研究的培训。资金还将帮助为拉蒙特·多尔蒂地球天文台的同位素实验室提供必要的设备。