RUI: Investigating the relationship between magmatic processes and copper mineralization at the Lights Creek Stock.

随着世界在未来几十年向绿色能源过渡，对金属的需求将不断增加。这是能源转型中最容易被忽视的问题之一。所有的金属都来自矿物，随着大型矿床的枯竭，小型矿床将变得更具经济可行性。这个项目将调查在加利福尼亚北部形成一个小的深部岩体的过程和它的伴生铜矿床的形成之间的关系。Lights Creek Stock的三个小型氧化铁-铜-金（IOCG）矿床正在被评估为未来的铜来源。当地下水和岩浆流体沿着裂缝改变现有岩石时，就形成了IOCG矿床。流体改变了岩石中的矿物质，并沿着裂缝沉积了新的铜矿物。这可以产生一个铜矿物的浓度，可能成为经济开采。了解岩浆过程如何影响铜矿的形成，可以为在其他地方寻找类似矿床提供信息。这项工作将由三名研究生，最多十二名本科生独立研究人员进行，并将包括三个班级项目。“真正的”研究经验（即当教师也不知道答案时）对于帮助STEM学生感觉自己是真正的科学家，增加他们作为科学家的自信和身份非常重要。该项目将支持三个班级的学生在课堂上进行真正的研究项目，极大地增加了学生在科罗拉多州立大学奇科分校地质学项目中的研究机会，因为只有不到一半的本科生通常会与一名教师一起进行独立研究。这些课堂项目的研究结果将与独立研究人员的研究结果相结合，以扩大对Lights Creek种群形成的理解。这项工作的目的是研究在Lights Creek Stock （LCS）中岩浆过程与铜矿化之间的时间和地球化学关系，LCS是内华达山脉北部的花岗岩类侵入岩，拥有三个IOCG（氧化铁铜金）铜矿床。拟议的工作将验证两个假设：1)LCS是通过数百万年的多次岩浆脉冲形成的；(2) LCS含矿的Superior、Moonlight和Engels IOCG矿床具有地球化学相关性，是LCS晚期岩浆流体与大气流体相互作用形成的。2021年的迪克西大火强烈烧毁了这个植被茂密的地区，揭示了新的露头，并允许比以前更详细的实地调查。详细的现场描述和花岗岩类岩石的样本收集将有助于通过岩石学、地球化学和地质年代学分析对LCS形成的历史模型进行重新评估。LCS内的垂直变化将通过类似的岩心样本分析来评估，这些岩心样本是由初级岩石学课程的学生在三个基于课程的本科研究经验（CUREs）中进行的。这些垂直和横向数据将被整合，以产生LCS的岩石成因模型（假设1）。在岩石学、地球化学和蚀变年代学的支持下，通过对几个岩心进行详细的岩心测井，分别作为质谱项目分析Superior和Engels IOCG矿床的岩石成因（假设2）。IOCG和LCS岩石成因模型的整合将产生一个更大的图像模型，将IOCG矿床与LCS的岩浆历史联系起来，然后可以在整个内华达山脉北部和世界各地的类似地区进行扩展。这项工作还将培养多达12名本科生和3名研究生，学习火成岩岩石学和经济地质学的研究方法，并让学生参与三个学期的真实研究体验。研究表明，参加研究经历可以提高学生在STEM领域的认同感、自我效能感和持久性。治疗增加了更广泛和更多样化的学生获得研究经验的机会，因此被归类为高影响力的教学实践。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。

As the world transitions to green energy over the next few decades, there will be an increasing demand for metals. This is one of the most overlooked issues in the energy transition. All metals come from minerals, and smaller ore deposits will become more economically viable as the larger ones are depleted. This project will investigate the relationships between the processes that formed a small pluton in northern California and the formation of its associated copper ore deposits. The three small iron oxide-copper-gold (IOCG) deposits of the Lights Creek Stock are being assessed as a future source of copper. IOCG deposits form when groundwater and magmatic fluids alter existing rocks along fractures. The fluids change the minerals in the rocks and deposit new copper minerals along the fractures. This can create a concentration of copper minerals which may become economic to mine. An understanding of how magmatic processes affect copper mineral formation can provide information about where to search for similar deposits elsewhere. This work will be carried out by three graduate students, up to twelve undergraduate independent researchers, and will also encompass three class projects. “Real” research experiences (i.e. when the instructor also doesn’t know the answer) have been shown to be very important in helping STEM students to feel like the real scientists they are, increasing their self-confidence and identity as scientists. This project will support three classes of students to carry out a real research project in the classroom, dramatically increasing student exposure to research in CSU-Chico’s geology program, as less than half of undergraduate students typically carry out independent research with a faculty member. The findings of these class projects will be integrated with the findings of the independent researchers to broaden understanding of the formation of the Lights Creek Stock.The goal of this work is to investigate the temporal and geochemical relationship between magmatic processes and copper mineralization within the Lights Creek Stock (LCS), a granitoid intrusion in the northern Sierra Nevada that hosts three IOCG (iron oxide copper gold) copper deposits. Proposed work will test two hypotheses: 1) LCS was emplaced through multiple pulses of magma over several million years; and 2) the LCS-hosted Superior, Moonlight and Engels IOCG deposits are geochemically related to one another, and were formed from the reaction between late-stage hydromagmatic fluids from the LCS and meteoric fluids. The Dixie Fire in 2021 intensely burned this densely vegetated area, revealing new outcrops and allowing for more detailed fieldwork than has previously been possible. Detailed field descriptions and sample collection of the granitoid rocks will aid reevaluation of a historic model for LCS formation through petrographic, geochemical and geochronological analysis of the lateral variation within the stock. Vertical variation within the LCS will be assessed through similar analyses of drillcore samples during three course-based undergraduate research experiences (CUREs) undertaken by students in a Junior-level petrology class. These vertical and lateral data will be integrated to produce a model for petrogenesis of the LCS (Hypothesis 1). The petrogenesis of the Superior and Engels IOCG deposits will be analyzed individually as MS projects through detailed core logging of several cores, supported by petrography, geochemistry and alteration geochronology (Hypothesis 2). The integration of the IOCG and LCS petrogenetic models will produce a bigger picture model to relate the IOCG deposits to the magmatic history of the LCS, which can then be scaled up throughout the northern Sierra Nevada and analogous regions throughout the world. This work will also train up to twelve undergraduate and three graduate students in research methods in igneous petrology and economic geology, as well as engaging three semesters of students in authentic research experiences. Research has shown that taking part in a research experience increases a student’s STEM identity, self-efficacy, and persistence in the field. CUREs increase access to research experiences to a broader and more diverse range of students, so are classed as a high-impact pedagogical practice.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.