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

这个CAREER项目将侧重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来作为岩浆活动的最好例子，岩浆活动是由地球内部深处的地幔柱上升而形成的。地幔柱假说为许多板块内火山活动提供了一种优雅的解释，比如夏威夷火山活动，它在整个地球历史上对塑造地球表面及其生物圈起着重要作用。然而，地幔柱的许多方面，甚至它们的存在，仍然存在高度争议。在这项研究中，研究者开始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变，以及它对地幔柱假说的影响。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夏季教育项目，以补充内华达大学拉斯维加斯分校（UNLV）地球科学系现有的强大的面向实地的研究和教育活动。这个暑期项目将利用系内的地球化学分析实验室来培养具有尖端地球化学分析技术的本科生。这个暑期项目以研究为导向，要求参与的学生在导师的指导下，利用现有的分析设施完成一个研究项目。PI计划对夏威夷六座火山的熔岩进行广泛的金属稳定同位素研究，包括Mg、Ca、Cr、Ti和Fe。它们覆盖了夏威夷的整个成分和同位素范围，代表了全球海洋岛屿玄武岩中发现的大部分。新的金属稳定同位素数据，连同已发表的同一熔岩的地球化学数据，将使PI能够更好地理解(1)夏威夷熔岩的地球化学结构，(2)夏威夷熔岩的岩石成因，以及(3)它们对羽流假说的影响。PI正在积极招募学生参加暑期研究项目，方法多种多样。UNLV多样化的学生群体确保了大部分参与的学生将来自代表性不足的群体。拟议的研究和教育活动是协同的，因为PI计划(1)使用拟议研究的一部分作为暑期计划的学生项目，(2)招募通过暑期计划训练的合格和积极的学生来从事他拟议的研究。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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 throught 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 summer education program focusing on analytical geochemistry, which complements the existing strong field-oriented research and education activities in the Geoscience Department at the University of Nevada Las Vegas (UNLV). This summer program will leverage the geochemical analytical labs inside the department to train undergraduate students with the cutting-edge geochemical analytical techniques. This summer 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 the summer research program using a variety of approaches. The diverse student body at UNLV 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 summer program, and (2) recruit qualified and motivated students trained through this summer 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.