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: 1129280
• 负责人: Michael Bizimis
• 金额: $ 12.06万
• 依托单位: University South Carolina Research Foundation
• 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=1129280&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.

该资助项目提供了第一组对大洋地幔 H2O 含量的测量，涉及学术机构和一家私营公司之间的合作，该公司拥有测量火成矿物中 H2O 的独特能力（高分辨率 FTIR）。 这项工作的重要性在于，地幔H2O含量的微小差异会对地幔流变学和地震结构产生深远的影响，这两者都会影响岩浆的生成和地壳运动，并对我们对地质灾害的理解和预测产生影响。 由于地幔无法直接进入，研究人员采用了一种巧妙的方法，测量来自夏威夷火山喷发和岩浆向上迁移过程中被撕裂的地幔岩石碎片（即捕虏体）的矿物质中的 H2O。 利用表明矿物形成深度的矿物对的成分关系，可以确定要研究的各种捕虏体的起源深度。 利用这些，可以通过傅里叶变换红外 (FTIR) 光谱检查矿物的 H2O 含量。 将分析沿着夏威夷岛链分布超过 300 公里的捕虏体，以及深达 100 公里的地幔深度。这项工作的更广泛影响是强大且多方面的。 该项目的一个主要影响是提供了更好地解释洋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。 它也是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参与一线研究。教师的研究将构成课堂和 K-12 教学材料的基础。劳动力培训将通过研究生和本科生参与最先进的地球化学分析技术来进行。 该计划指出，该研究生来自科学领域代表性不足的群体。