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）知识分子的优点：这项工作旨在了解拟议的热点起源的火山海洋岛附近的浅海地板的起源。 这项工作对于我们对羽状地球动力学的理解至关重要，羽流与岩石圈的相互作用以及羽状火山的起源至关重要。 研究目标是夏威夷膨胀，是这些地区最广泛研究的。该工作使用橄榄岩岛上Kaua'i岛的详细的地球化学分析（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变薄模型。 化学数据将用于鉴定来自太平洋岩石圈和地幔羽流的橄榄岩的特征。如果在Kaua`I上发现了与羽流有关的橄榄石和原位太平洋岩石圈组成，就像它们在O'Ahu一样，这证明了大规模侵蚀和通过下游夏威夷岛下游的太平洋岩石圈替换。 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. 由此产生的工作将为木圈上方的岩石圈提供新的，前所未有的4维（时空）视图。Broader的影响：这项研究直接补充了其他NSF资助的项目，其目的是图像夏威夷Swell的根源，并通过研究夏威夷岛上的二级火山岛的起源来形象。 结果将以全国专业会议的出版物和演讲形式传播。该研究支持佛罗里达州立大学的一名早期职业科学家，并将涉及本科地球科学专业的专业，参与与本研究的主要研究目标直接相关的项目。 这项研究还将通过国家高磁场实验室（NHMFL）的NSF资助的REU计划参与和培训本科科学专业的专业，并将通过NHMFL的持续外展计划参与并培训中学生在地球科学中进行研究。 年度NHMFL开放日将发生额外的公共外展活动。