CAREER: Petrogenesis of Hawaiian lavas, Constraints from metal stable isotopes

这个职业项目将专注于了解夏威夷喷发的岩浆的来源。夏威夷火山活动经常被用作岩浆作用的最佳例子，岩浆作用是由地幔热柱从地球内部深处上升形成的。地幔热柱假说为许多板内火山活动提供了优雅的解释，例如夏威夷，它在地球历史上塑造地球表面及其生物圈方面发挥了重要作用。然而，地幔热柱的许多方面，甚至它们的存在，仍然存在着激烈的争论。在这项研究中，研究人员着手使用几种最先进的地球化学和同位素示踪剂来了解夏威夷火山活动的演化，以及它对地幔热柱假说的影响。在这些建议的示踪剂中，他将对一组夏威夷样品进行几种新型金属稳定同位素示踪剂的系统分析。PI还计划开展一个以分析地球化学为重点的冬季教育项目，该项目将利用系内的地球化学分析实验室来培训本科生掌握尖端的地球化学分析技术。这个冬季项目是以研究为导向的，要求参与的学生在他们的教师指导下使用可用的分析设备完成一个研究项目。PI建议对来自六个夏威夷火山的经过充分研究的熔岩进行广泛的金属稳定同位素调查，包括镁、钙、铬、钛和铁。它们覆盖了夏威夷的整个成分和同位素范围，占全球洋岛玄武岩中发现的很大一部分。新的金属稳定同位素数据，以及已公布的关于同一熔岩的地球化学数据，将使PI能够更好地理解(1)夏威夷岩柱的地球化学结构，(2)夏威夷熔岩的岩石成因，以及(3)它们对岩柱假说的影响。PI正在积极招募学生参加冬季研究项目，方法多种多样。UTK多样化的学生群体确保了很大比例的参与学生将来自代表性不足的群体。建议的研究和教育活动是协同的，因为PI计划(1)将建议研究的一部分用作冬季计划的学生项目，(2)招募通过该冬季计划培训的合格和有积极性的学生从事他建议的研究。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This CAREER project will focus on understanding the source of the magmas that erupt in Hawaii. Hawaiian volcanism is often used as the best example of magmatism formed by the rise of a mantle plume from deep in the Earth's interior. The mantle plume hypothesis provides an elegant interpretation for many intra-plate volcanism, such as Hawaii, which has been important in shaping the Earth’s surface and its biosphere through Earth's history. However, many aspects of mantle plumes, and even their existence, remain highly debated. In this study, the investigator sets out to use several state-of-the-art geochemical and isotopic tracers to understand the evolution of Hawaiian volcanism, and its implications for the mantle plume hypothesis. Among those proposed tracers, he will conduct the systematic analysis of several novel metal stable isotope tracers on for a set of Hawaiian samples. The PI also plans a winter education program focusing on analytical geochemistry, which will leverage the geochemical analytical labs inside the department to train undergraduate students with the cutting-edge geochemical analytical techniques. This winter program is research oriented and requires the participating students to complete a research project using the available analytical facilities under the supervision of their faculty mentors.The PI proposes an extensive metal stable isotope investigation, including Mg, Ca, Cr, Ti, and Fe, on well-studied lavas from six Hawaiian volcanoes. They cover the whole compositional and isotopic ranges in Hawaii, which represent a large portion of those found in global ocean island basalts. The new metal stable isotope data, together with the published geochemical data on the same lavas, will allow the PI to better understand (1) the geochemical structure of the Hawaiian plume, (2) the petrogenesis of Hawaiian lavas, and (3) their implications to the plume hypothesis. The PI is actively recruiting students into a winter research program using a variety of approaches. The diverse student body at UTK ensures that a large proportion of the participating students will be from underrepresented groups. The proposed research and education activities are synergistic, because the PI plans to (1) use part of the proposed research as student projects of the winter program, and (2) recruit qualified and motivated students trained through this winter program to work on his proposed research.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.