CAREER: Heavy Noble Gases in the Azores Archipelago

职业：亚速尔群岛的重惰性气体

• 批准号: 2145663
• 负责人: Rita Parai
• 金额: $ 72.09万
• 依托单位: Washington University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2145663&HistoricalAwards=false
• 关键词: CAREER; Heavy; Noble; Gases; Azores

The terrestrial atmosphere and ocean are unique among Solar System bodies. The heavy noble gases (neon, argon, krypton and xenon) trace where volatiles elements and compounds like carbon, nitrogen and water originated and how their budgets have been distributed between the deep Earth and surface reservoirs over time. Measurements of heavy noble gases in volcanic samples from localities influenced by mantle plumes have yielded new insights into volatile origins and transport, but precise data have come from unusual samples, rather than typical subaerially-erupted ocean island basalts. This integrated research and educational work will harness new technical capabilities to measure heavy noble gases in subaerially-erupted ocean island basalts from the Azores archipelago; this will shed light on how the mantle plume sampled at the Azores acquired and lost volatiles over Earth history and advance the field towards a better understanding of mantle plume volatile signatures. A modern curriculum that presents different isotope systems used to study the geochemistry of the mantle within a uniform framework will be developed and disseminated to broaden the pool of undergraduates who pursue advanced study of the geochemistry of the deep Earth. The heavy noble gases (neon, argon, krypton and xenon) provide unique and powerful insights into volatile accretion, early mantle differentiation, and volatile transport between the interior and surface reservoirs. However, heavy noble gases are difficult to measure in most ocean island basalts due to sample degassing and atmospheric contamination. New analytical techniques have enabled the measurement of heavy noble gas compositions resolved from the atmospheric composition in olivines from ocean islands. This project will sample well-studied sites in the Azores archipelago to obtain large quantities of fresh material for high-precision analysis of helium, neon, argon, krypton and xenon abundances and isotopic ratios. New data will be used to probe mantle volatile origins, test for heterogeneous signatures of volatile loss among mantle plumes, and investigate the efficiency of atmospheric volatile transport into the mantle in the deep past. This project will develop and test a new introductory curriculum for mantle radiogenic isotope geochemistry including noble gases, presented within a unifying framework. Work to disseminate the curriculum to teachers through a workshop and online portals and facilitate its integration into courses will increase and broaden the pool of undergraduates who pursue advanced study of mantle geochemistry, including the noble gases.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.

地球大气层和海洋在太阳系天体中是独一无二的。重惰性气体（氖、氩、氪和氙）追踪挥发性元素和化合物（如碳、氮和水）的来源，以及它们的收支如何随着时间的推移在地球深部和地表储层之间分配。对受地幔柱影响的火山样品中重惰性气体的测量，使人们对挥发性物质的起源和运输有了新的认识，但精确的数据来自不寻常的样品，而不是典型的海底喷发的洋岛玄武岩。这项综合研究和教育工作将利用新的技术能力来测量亚速尔群岛海底喷发的洋岛玄武岩中的重惰性气体;这将揭示亚速尔群岛地幔柱采样如何在地球历史上获得和失去挥发物，并推动该领域更好地了解地幔柱挥发物特征。将编制和传播一套现代课程，介绍在统一框架内研究地幔地球化学所用的不同同位素系统，以扩大对地球深部地球化学进行深入研究的本科生队伍。重惰性气体（氖，氩，氪和氙）提供了独特的和强大的洞察挥发性吸积，早期地幔分化，内部和表面水库之间的挥发性运输。然而，由于样品脱气和大气污染，大多数洋岛玄武岩中的重惰性气体难以测量。新的分析技术使得能够测量从海洋岛屿橄榄石的大气成分中分离出来的重惰性气体成分。该项目将在亚速尔群岛经过充分研究的地点进行取样，以获取大量新鲜材料，用于对氦、氖、氩、氪和氙的丰度和同位素比率进行高精度分析。新的数据将用于探测地幔挥发物的来源，测试地幔柱之间挥发物损失的非均匀特征，并调查过去深部大气挥发物向地幔输送的效率。该项目将制定和测试一个新的地幔放射成因同位素地球化学入门课程，包括惰性气体，在一个统一的框架内提出。通过研讨会和在线门户网站向教师传播课程并促进其融入课程的工作将增加和扩大对地幔地球化学（包括惰性气体）进行高级研究的本科生的人数。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。