Constraints on the Hawaiian Swell and Plume-lithosphere Interaction from Kaua`i Mantle Xenoliths

可爱岛地幔包体对夏威夷涌浪和地幔柱-岩石圈相互作用的限制

• 批准号: 0852488
• 负责人: Michael Bizimis
• 金额: $ 12.31万
• 依托单位: University South Carolina Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-06 至 2010-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0852488&HistoricalAwards=false
• 关键词: Constraints; Hawaiian; Swell; Plume; lithosphere

ABSTRACT: 0622827 (Bizimis)Intellectual merit: This work seeks to understand the origin of the shallow ocean floor around volcanic ocean islands of proposed hotspot origin. The work is crucial to our understanding of plume geodynamics, how plumes interact with the lithosphere, and the origin of plume volcanism. The Hawaiian swell, the most extensively studied of these regions, is the research target. The work tests two different geophysical lithosphere thinning models using detailed geochemical analyses (Hf-Os-Nd-Sr-Pb isotopes, trace and major element concentrations) of peridotite xenoliths from the island of Kaua`i. Chemical data will be used to identify the signatures of peridotites from the Pacific lithosphere and from the mantle plume. If peridotites with both plume-related and in situ Pacific lithosphere compositions are found at Kaua`i, as they are in O`ahu, this is evidence for large-scale erosion and replacement of the Pacific lithosphere by the plume downstream from its present center under the island of Hawai'i. Rare garnet pyroxenite xenoliths from Ka`ula island, and garnet pyroxenites with "majorite" precursors from Salt Lake Crater, O`ahu, which represent some of the deepest samples from the oceanic mantle will also be analyzed to try and identify different proposed origins of the pyroxenites, and identify them as either recycled oceanic crust or high pressure cumulates. The resulting work will provided a new and unprecedented, 4-dimensional (space and time) view of the lithosphere above a plume.Broader impacts: This research directly complements other ongoing NSF-funded projects, whose objective is to image the root of the Hawaiian swell and determine the origin of the secondary volcanism around the Hawaiian Islands through the study of lavas. Results will be disseminated in the form of publications and presentations at national professional meetings. The research supports an early career scientist in at Florida State University and will involve undergraduate Earth Sciences majors in projects directly related to the main research objectives of this study. This research will also involve and train undergraduate science majors through a NSF-funded REU program at the National High Magnetic Field Lab (NHMFL), and will involve and expose middle school students to research in earth sciences through ongoing outreach programs at the NHMFL. Additional public outreach will occur at the annual NHMFL Open House.

摘要：0622827 (Bizimis)智力价值：这项工作旨在了解拟议热点起源的火山岛周围浅海海底的起源。 这项工作对于我们理解羽流地球动力学、羽流如何与岩石圈相互作用以及羽流火山活动的起源至关重要。 夏威夷海浪是这些地区中研究最广泛的，也是研究目标。这项工作使用可爱岛橄榄岩捕虏体的详细地球化学分析（Hf-Os-Nd-Sr-Pb 同位素、痕量和主要元素浓度）测试了两种不同的地球物理岩石圈减薄模型。 化学数据将用于识别太平洋岩石圈和地幔柱中橄榄岩的特征。如果像在瓦胡岛一样，在考爱岛发现了具有与羽流相关的橄榄岩和原位太平洋岩石圈成分的橄榄岩，那么这就是太平洋岩石圈被目前中心下游的羽流大规模侵蚀和取代的证据夏威夷岛下方。 来自卡乌拉岛的稀有石榴石辉石岩捕虏体，以及来自欧胡岛盐湖陨石坑的具有“长辉石”前体的石榴石辉石岩，它们代表了大洋地幔的一些最深样本，也将进行分析，以尝试确定不同的拟议起源。辉石岩，并将它们识别为回收的洋壳或高压累积物。 由此产生的工作将为羽流上方的岩石圈提供一个新的、前所未有的 4 维（空间和时间）视图。更广泛的影响：这项研究直接补充了其他正在进行的 NSF 资助的项目，其目标是对夏威夷的根部进行成像通过研究熔岩，膨胀并确定夏威夷群岛周围次生火山活动的起源。 结果将以出版物和在国家专业会议上演讲的形式传播。该研究支持佛罗里达州立大学的一名早期职业科学家，并将让地球科学专业的本科生参与与本研究的主要研究目标直接相关的项目。 这项研究还将通过 NSF 资助的国家强磁场实验室 (NHMFL) 的 REU 项目吸引和培训本科生科学专业，并将通过 NHMFL 正在进行的外展项目让中学生接触地球科学研究。 年度 NHMFL 开放日将进行额外的公众宣传活动。