CAREER: Tracking mantle carbon through the life cycle of Large Igneous Provinces

纵观地球历史，被称为大火成岩省（LIPs）的巨大火山爆发与大规模灭绝和气候变暖事件相吻合。追踪这些火山喷发释放的二氧化碳是解决岩浆活动与观测到的气候变化之间联系的关键。然而，由于CO2往往会从岩浆中泄漏出来，因此测量过去喷发的CO2具有挑战性。该职业奖将使用从三个可能记录过去二氧化碳浓度的LIP中精心挑选的样本来调查不同的LIP来源。这项工作的目标是澄清如何，何时以及为什么一些LIP爆发会对地球上的气候和生命造成重大破坏，而其他人则不会。新方法将追踪地球深处的二氧化碳，为过去气候的估计提供信息，并有助于预测未来的气候变化。该项目在本科课程中使用同伴指导，将研究，公众参与和教学结合起来。这项工作还支持研究生和本科生在一个公共机构与不同的学生群体的培训。该项目的一部分包括与一位电影制片人合作，通过一部新的纪录片和在纽约虚拟火山观测站的宣传，传达过去气候中断的教训。这部电影和宣传活动将使每年夏天成千上万的游客获得探索火山的体验。 本研究的两个主要科学目标是在LIP岩浆中找到最真实的岩浆CO2记录，并控制不同的地幔来源，以了解LIP生命周期中地幔碳的释放。因此，该项目设计了一系列自然实验，对比：1）不同类型的熔体包裹体挥发性和微量元素记录，以及2）来自海洋和大陆LIP的样本，这些样本挖掘了不同的和不断发展的地幔来源。这些自然实验将揭示玄武岩岩浆中CO2的各种岩石学档案的优点和缺点，包括一系列熔融包裹体宿主晶体和原始CO2的地球化学代理。结果将被用来测试的假设，这是不断发展的地幔水库在LIP熔融，而不是沉积围岩，因为通常假设，确定气候变暖和碳循环中断的严重性和速度，以应对岩浆活动。如果成功，该项目将阐明地幔中知之甚少的储层的挥发性系统学，包括大陆地幔岩石圈，地幔柱中的再循环物质，高3 He/4 He原始地幔-该奖项反映了NSF的法定使命，并被认为值得通过以下方式予以支持：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。

Throughout Earth’s history, enormous volcanic eruptions known as Large Igneous Provinces (LIPs) coincide with mass extinction and climate warming events. Tracking CO2 release from these eruptions is key to resolving links between magmatism and observed climatic changes. However, because CO2 tends to leak out of magmas, measuring CO2 from past eruptions is challenging. This CAREER award will investigate distinct LIP sources using carefully selected samples from three LIPs that may record past CO2 concentrations. The goal of this work is to clarify how, when, and why some LIP eruptions cause major disruptions in climate and life on Earth but others do not. New approaches will track CO2 deeper in the Earth, inform estimates of past climate, and help to project future climate change. The project uses peer mentoring in undergraduate course to integrate research, public engagement and teaching. The work also supports graduate and undergraduate student training at a public institution with a diverse student population. Part of the project includes collaboration with a film-maker to convey lessons from past climate disruptions through a new documentary and outreach at the New York Virtual Volcano Observatory. The film and outreach will make the experience of exploring a volcano accessible to thousands of visitors each summer. The two primary scientific objectives of this work are to find the most faithful records of magmatic CO2 in LIP magmas, and to control for different mantle sources to understand mantle carbon release through the life cycle of LIPs. Accordingly, this project frames a series of natural experiments that contrast: 1) different types of melt inclusion volatile and trace element records, and 2) samples from oceanic and continental LIPs that tap distinct and evolving mantle sources. These natural experiments will reveal the strengths and weaknesses of various petrologic archives of CO2 in basaltic magmas, including a range of melt inclusion host crystals and geochemical proxies for original CO2. The results will be used to test the hypothesis that it is the evolving mantle reservoirs tapped during LIP melting—rather than sedimentary country rocks as is commonly assumed—that determine the severity and pace of climatic warming and carbon cycle disruption in response to magmatism. If successful, this project will elucidate the volatile systematics of poorly understood reservoirs in the mantle including the continental mantle lithosphere, recycled material in plumes, and high 3He/4He primordial mantle—in the process demonstrating how the origins of LIPs in the mantle can set the blueprint for surface CO2 release and climate change.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.