IRES: TRACK 1: RUI: COLLABORATIVE RESEARCH: THE PERMO-TRIASSIC CHOIYOI SILICIC LARGE IGNEOUS PROVINCE: REGIONAL VOLCANIC FRAMEWORK AND POTENTIAL IMPACT ON GLOBAL CLIMATE

火山活动在全球气候变化和物种大灭绝事件中的作用在地质学和生物学中都是一个有争议的话题。在晚泥盆世（~364 Ma）、中二叠世（259 Ma）、晚二叠世（248 Ma）和晚三叠世（~206 Ma）的大火成岩省与大灭绝事件之间建立了明确的时间联系。这些大型火山活动被怀疑是造成全球变暖和海洋缺氧的原因，原因是温室气体的大量排放。相反，硅质大火成岩省和由此产生的酸雨、臭氧消耗、硫酸盐气溶胶和海洋铁施肥在大规模灭绝事件中的作用尚未得到评估。阿根廷-智利的二叠-三叠纪Choiyoi群是一个主要的高纬度硅质大火成岩省，其走向长度为2000公里，体积相当于125个黄石火山同时喷发。Choiyoi岩浆活动与几个主要的早二叠纪气候事件重叠，包括Olsen？s灭绝（~272 Ma）和Kamura冷却事件（~262 Ma）。这项国际学生研究经验（IRES）提案提供了一种创新的沉浸式体验，旨在吸引三组美国本科生和研究生在三年内进行假设驱动的实地密集研究项目，调查硅大火成岩省（SLIPS）与全球气候变化之间的联系。该项目将通过评估硅火山作用在气候变化中的潜在作用来推进科学发展，促进美国和阿根廷研究团队之间的国际合作，通过有意指导三组研究生和本科生来促进教育，并通过纳入来自STEM领域代表性不足群体的学生来增加地球科学的多样性。圣地亚哥州立大学的地球科学系和威斯康星大学欧克莱尔分校的地质系都致力于扩大地球科学领域的多样性，并积极从代表性不足的群体中招募学生进入STEM领域。要准确重建Choiyoi岩浆活动及其与气候变化的关系，需要整合岩浆省内几个重点地区的地层、构造、地质年代学、岩石学、同位素、地球化学和热年代学数据。在项目的三年时间里，将依次对岩浆省的南部、中部和北部三个重点区域进行研究。每个重点区域有五个重点，包括1)地层学/火山相；2)岩石学，包括矿物化学和流体包裹体分析；3) U/Pb锆石年代学及Hf分析；4)主要元素、微量元素和稀土元素地球化学；5)构造分析，包括热年代学。安第斯山脉中南部是研究这一系统的理想的自然实验室，因为1)暴露和可达性；2)建立地质格架；3)有高素质的导师；4)使用美国和阿根廷的分析设施；5)合作pi在区域地质学和学生体验活动中的经验。本研究评估了硅质大型火成岩复合体的时空演化与全球气候变化之间的潜在关系，并为学生提供了一个理想的机会，让他们参与假设驱动的科学研究。该项目涉及三组五(5)名学生，在由美国和阿根廷导师组成的高素质团队的指导下，在安第斯山脉中南部进行假设驱动的实地深入研究。学生研究人员将在由2-3名学生研究人员和1-2名导师组成的综合团队中进行实地考察，团队的组成定期轮换。学生合作者（3名硕士，9名学士）将参与威斯康星大学奥克莱尔分校、SDSU、亚利桑那大学和科罗拉多大学博尔德分校的实地和实验室分析的各个方面，包括地层学研究、火山学、地质年代学、地球化学和同位素分析。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。

The role of volcanism in global climate change and mass extinction events is a controversial topic in geology and biology. A clear temporal linkage has been established between basaltic large igneous provinces and mass extinction events in the Late Devonian (~364 Ma), Middle Permian (259 Ma), Late Permian (248 Ma) and Late Triassic (~206 Ma). These large volcanic events are suspected to cause global warming and marine anoxia due to high levels of greenhouse gas emissions. Conversely, the role of silicic large igneous provinces and resultant acid rain, ozone depletion, sulphate aerosols and ocean Fe fertilization in mass extinction events has not been assessed. The Permo-Triassic Choiyoi Group of Argentina-Chile is a major high-latitude silicic large igneous province that has a strike length of 2000 km and a volume equivalent to 125 Yellowstone calderas erupting essentially simultaneously. Choiyoi magmatism overlaps with several major early Permian climatic events including Olsen?s extinction (~272 Ma) and the Kamura cooling event (~262 Ma). This International Research Experiences for Students (IRES) proposal offers an innovative immersion experience designed to engage three cohorts of U.S. undergraduate and graduate students over three years in a hypothesis-driven, field-intensive research project investigating the linkage between silicic large igneous provinces (SLIPS) and global climatic change. This project will advance science by providing an assessment of the potential role of silicic volcanism in climate change, foster international collaboration between U.S. and Argentinian research teams, promote education through the intentional mentoring of three cohorts of graduate and undergraduate students and increase diversity in the geosciences by inclusion of students from groups underrepresented in STEM fields. Both the Department of Geosciences at SDSU and in the Department of Geology at UW-Eau Claire are committed to expanding diversity within the geosciences and are actively recruiting students from underrepresented groups into STEM fields.An accurate reconstruction of Choiyoi magmatic activity and its relation to climatic change requires an integration of stratigraphic, structural, geochronologic, petrologic, isotopic, geochemical, and thermochronologic data from several focus areas within the magmatic province. Three focus areas will be targeted within the southern, central and northern portions of the magmatic province that will be addressed sequentially over the three year duration of the project. There are five major emphases within each focus area, including 1) stratigraphy/volcanic facies; 2) petrology, including mineral chemistry and fluid inclusion analysis; 3) U/Pb zircon geochronology and Hf analyses; 4) major, trace and REE geochemistry; 5) structural analysis, including thermochronology. The south-central Andes are an ideal natural laboratory to study this system due to 1) exposure and accessibility; 2) established geologic framework; 3) availability of highly-qualified mentors; 4) access to analytical facilities in U.S. and Argentina; and, 5) experience of co-PIs in both regional geology and student experiential activities. This investigation evaluates the potential relationship between the spatial and temporal evolution of a silicic large igneous complex and global climatic change and provides an ideal opportunity to engage students in hypothesis-driven scientific research. This project involve three cohorts of five (5) students conducting hypothesis-driven, field intensive research in the south-central Andes under the mentorship of a highly qualified team of U.S. and Argentinian mentors. Student researchers will conduct fieldwork within integrated teams consisting of 2-3 student researchers and 1-2 mentors, with the composition of the teams rotating on a regular basis Student collaborators (3 M.Sc., 9 B.Sc.) will be involved in all aspects of field and laboratory analyses, including stratigraphic studies, volcanology, geochronology, geochemistry, and isotopic analyses at UW-Eau Claire, SDSU, U. Arizona and U. Colorado-Boulder.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.