CSEDI Collaborative Research: Joint seismic, geodynamic, and mineral physics investigation of mantle plumes

CSEDI 合作研究：地幔柱的地震、地球动力学和矿物物理联合调查

• 批准号: 0855487
• 负责人: Peter van Keken
• 金额: $ 29.49万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-15 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0855487&HistoricalAwards=false
• 关键词: CSEDI; Collaborative; Research; Joint; seismic

The concepts of hotspots and plumes have taken a central place in global geophysical and geochemical research. A common theory to explain the persistent excess volcanism at locations such as Hawaii, Iceland and Yellowstone is that they are supported by columnar upwelling of hot mantle rock called mantle plumes. Yet, these plumes have remained elusive in seismological images of the mantle. While a variety of seismological studies suggest the presence of hot anomalies below hotspot regions, a detection of a narrow whole-mantle plume has yet to be widely accepted.By combining multidisciplinary expertise, we wish to provide fundamental and quantitative tests of the plume hypothesis. We will establish answers to the following basic questions that address the physics of plume formation, morphology and longevity in Earth and the seismological resolution of plume signatures in seismic data: What are the possible plume structures given geophysical constraints? What is the expected plume signature in tomographic images? Do deep mantle plumes impart observable wave perturbations?We address these questions using a combined geodynamical, mineral physics, and seismological analysis. The proposing team forms an international collaboration between Jeroen Ritsema and Peter van Keken at Michigan, Derek Schutt at Colorado State, and Saskia Goes at London's Imperial College. We will develop new experience on establishing the structure of plumes and how they are mapped in seismological data sets. This will allow us to determine the optimal data sets and seismic techniques for mapping plumes in the mantle and to understand whether and where mantle plumes can be imaged. The grant will support the interdisciplinary education of three female graduate students and will foster an international collaboration between scientists from the US and the UK. Our Yellowstone studies may prove helpful in forthcoming EarthScope data analysis and the design of a Flexible Array deployment aimed at the Yellowstone hotspot.

热点和羽流的概念在全球地球物理和地球化学研究中占据了中心地位。解释夏威夷、冰岛和黄石公园等地持续存在的过量火山活动的一个常见理论是，它们是由称为地幔柱的热地幔岩石的柱状上涌支撑的。然而，这些羽流在地幔的地震图像中仍然难以捉摸。虽然各种地震学研究表明热点区域下方存在热异常，但狭窄的全地幔羽流的检测尚未被广泛接受。通过结合多学科专业知识，我们希望为羽流假说提供基础和定量检验。我们将为以下基本问题找到答案，这些问题涉及地球中羽流形成、形态和寿命的物理学以及地震数据中羽流特征的地震学分辨率：在给定地球物理约束的情况下，可能的羽流结构是什么？断层扫描图像中预期的羽流特征是什么？ 深部地幔柱是否会产生可观测到的波扰动？我们通过综合地球动力学、矿物物理学和地震学分析来解决这些问题。该提案团队由密歇根大学的 Jeroen Ritsema 和 Peter van Keken、科罗拉多州立大学的 Derek Schutt 以及伦敦帝国理工学院的 Saskia Goes 组成了国际合作团队。 我们将在建立羽流结构以及如何将其映射到地震数据集中积累新的经验。这将使我们能够确定绘制地幔羽流图的最佳数据集和地震技术，并了解是否以及在何处可以对地幔羽流进行成像。该赠款将支持三名女研究生的跨学科教育，并将促进美国和英国科学家之间的国际合作。我们的黄石研究可能有助于即将进行的 EarthScope 数据分析和针对黄石热点的灵活阵列部署设计。