Collaborative Research: Magnetic Ocean Crust: High-Fidelity Geomagnetic Field Recorder and Sensitive Indicator of Magmatic, Tectonic, and Alteration Processes

智力优势：这项研究使用经典的、最先进的和新的技术来研究大洋钻探计划钻芯中的氧化铁矿物的磁性、岩石学和地球化学特征，以确定海底磁异常的性质和成因。它还将确定哪些矿物是地球地磁场的忠实记录者，以及这些矿物在地壳的什么深度发生和/或改变。研究还考察了矿物成分、粒度和蚀变状态对海底火山岩磁信号的影响。测量的特性将被用来了解洋壳的岩浆、构造和蚀变历史，以及地球地磁场强度和方向的变化。将分析穿透几乎整个洋壳部分的岩芯，并使用自然和感应剩余磁化以及磁滞特性、磁化率、力矩和在高、低和室温下的力分布来确定磁性。铁氧化物的组成、氧化状态和矿物特性将通过反射光学显微镜、电子探针和扫描电子显微镜来确定。古强度将使用Thellier类型的方法，以及最近公布的修改和两种新的勘探方法来估计。更广泛的影响：这项工作的更广泛的影响包括开发古地磁研究的新方法；机构之间的合作，其中一个机构处于EPSCoR状态；以及科学和工程学中代表不足的少数人对PI的支持。这项工作还支持本科生的培训，并通过大学开放参观活动进行公众宣传。

Intellectual Merit: This research uses classical, state-of-the-art, and new techniques to investigate the magnetic, petrologic, and geochemical characteristics of iron oxide minerals from Ocean Drilling Program drill cores to determine the nature and genesis of seafloor magnetic anomalies. It will also determine which minerals are faithful recorders of Earth's geomagnetic field and at what depths in the crust they minerals occur and/or alter. The research also examines the impact of mineral composition, grain size, and alteration state on the magnetic signal of seafloor volcanic rocks. The measured properties will be used to understand the magmatic, tectonic, and alteration history of the ocean crust, as well as changes in Earth's geomagnetic field strength and direction. Cores that penetrate nearly an entire section of ocean crust will be analyzed and magnetic properties will be determined using natural and induced remnence magnetizations, as well as hysteresis properties; susceptibilities; moments; and FORC distributions at high, low, and room temperatures. Composition, oxidation state, and mineral characteristics of the iron oxides will be determined from reflected light microscopy, electron microprobe, and scanning electron microscopy. Paleointensities will be estimated using Thellier-type methods, along with recently published modifications and two new exploratory methods. Broader Impacts: Broader impacts of the work include development of new methods for paleomagnetic studies; collaboration between institutions, one of which is in an EPSCoR state; and support of a PI from a minority under-represented in science and engineering. The work also supports undergraduate training and has a component of public outreach through a university Open House.