Collaborative research: Water stratigraphy of the oceanic lithosphere using mantle xenoliths from Hawaii

合作研究：利用夏威夷地幔捕虏体进行海洋岩石圈水地层学

• 批准号: 1129072
• 负责人: Anne Peslier
• 金额: $ 4.78万
• 依托单位: Jacobs Technology Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1129072&HistoricalAwards=false
• 关键词: Collaborative; research; Water; stratigraphy; oceanic

The funded project provides the first set of measurements of the H2O content of the oceanic mantle and involves collaboration between an academic institution and a private sector firm that has a unique capability to measure H2O in igneous minerals (high-resolution FTIR). The importance of this work lies in the fact that small differences in mantle H2O content can have profound effects on mantle rheology and seismic structure, both of which can impact magma generation and crustal movement and have implications for our understanding and prediction of geohazards. Because the mantle is not directly accessible, the investigators implemented a clever approach in which H2O will be measured in minerals coming from pieces of mantle rock (i.e., xenoliths) that were ripped up during the eruption and upward migration of magma of Hawaiian volcanoes. Using compositional relations of mineral pairs that indicate the depth at which the minerals formed, the depth of origin of the various xenoliths that are to be studied can be determined. Using these, the H2O content of the minerals will be examined by Fourier Transform Infra Red (FTIR) spectroscopy. Xenoliths distributed over 300 km along the Hawaiian Island chain and mantle depths to up to 100 km will be analyzed. Broader impacts of the work are robust and multifaceted. A major impact of the project is the provision of essential data that is needed to better interpret the seismic structure of the ocean crust, which will impact our ability to better model the source areas of geohazards like volcanoes and subduction zone earthquakes. The work also supports collaboration between a public university in an EPSCoR state and private industry. It also has a significant component of in-service teacher training where high school teachers in South Carolina work in the laboratory of the lead PI during the summer, getting a chance to engage in frontline research with academic scientist. The teacher?s research will form the basis for classroom and K-12 instructional materials. Workforce training will be carried through the involvement of graduate and undergraduate students in state-of-the-art geochemical analytical techniques. The Program notes that the graduate student is from a group under-represented in the science.

该资助项目提供了海洋地幔H2O含量的第一套测量结果，并涉及一个学术机构和一个私营部门公司之间的合作，该公司具有测量火成岩矿物中H2O的独特能力（高分辨率FTIR）。 这项工作的重要性在于，地幔H2O含量的微小差异可以对地幔流变学和地震结构产生深远的影响，这两者都可以影响岩浆生成和地壳运动，并对我们的认识和预测地质灾害具有意义。 由于地幔不能直接进入，研究人员实施了一种聪明的方法，其中H2O将在来自地幔岩石碎片的矿物中测量（即，捕虏体），这些捕虏体是在夏威夷火山爆发和岩浆向上迁移过程中被撕裂的。 利用指示矿物形成深度的矿物对的成分关系，可以确定待研究的各种捕虏体的起源深度。 使用这些，矿物的H2O含量将通过傅立叶变换红外（FTIR）光谱进行检查。 将分析沿夏威夷岛链沿着300公里以上分布的捕虏体和深达100公里的地幔。这项工作的广泛影响是强有力和多方面的。 该项目的主要影响是提供了更好地解释海洋地壳地震结构所需的基本数据，这将影响我们更好地模拟火山和俯冲带地震等地质灾害源区的能力。 这项工作还支持EPSCoR州的公立大学与私营企业之间的合作。 它也有在职教师培训的重要组成部分，南卡罗来纳州的高中教师在夏季在首席PI的实验室工作，有机会与学术科学家一起从事一线研究。老师？的研究将成为课堂和K-12教学材料的基础。将通过让研究生和本科生参与最先进的地球化学分析技术来进行劳动力培训。 该计划指出，研究生是从一组代表性不足的科学。