EOR: Reactive Melt Migration in the Lower Oceanic Crust in IODP Hole U1309D at the Atlantis Core Complex, 30°N, Mid-Atlantic Ridge

该项目的研究人员在海洋钻探计划的支持下，计划调查岩浆渗透和熔体迁移引起的反应流在多大程度上改变了大西洋中脊下地壳的地球化学和岩石学特征。这项地球化学研究将集中在大西洋中脊亚特兰蒂斯海洋核杂岩的样品上，这些样品是在IODP探险304和305中回收的，地震折射数据表明，在浅层深处，地幔速度为8公里/秒。这个项目是一个国际合作项目，有德国和法国的研究人员参与。所提出的项目的智力价值在于，通过对这一海洋地壳非常新鲜的样品进行精确的主、微量元素和同位素分析，可以更好地约束一个重要的地壳形成过程。研究计划包括一个综合的地球化学方法，该方法将提供从岩心部分回收的矿物的详细特征，这些岩心部分主要由浅层的北辉长岩、中层的橄榄岩辉长岩和较深层的富含橄榄石的橄榄岩组成。研究结果将有助于揭示岩浆渗透和熔体迁移过程中海洋地壳发生的地球化学和岩石学变化。不同的合作者将努力整合他们的结果，以更好地了解这200多米侵入段的下地壳熔体侵位、渗透和相互作用。就更广泛的影响而言，该项目将通过引进德国马克斯普朗克研究所最先进的ICP-MS分析技术，为夏威夷大学和美国的研究和教育基础设施做出贡献，该技术由该提案的博士后实习生Matthias Willbold博士开发。这项研究还将促进夏威夷大学和国际实验室之间的国际伙伴关系。研究结果将在科学文献中公布，也可通过IODP系统的外展计划和通识教育网站获得。最后，该项目将支持两名新的nsf支持的研究人员的早期职业发展。

This investigators of this project, supported by the Ocean Drilling Program, plan to investigate the extent by which reactive flow caused by magma infiltration and melt migration alters the geochemical and petrologic characteristics of the lower crust underneath the Mid Atlantic Ridge. This geochemical study will focus on samples from the Atlantis Oceanic Core Complex on the Mid-Atlantic Ridge that were recovered in IODP expeditions 304 and 305, and where seismic refraction data indicate mantle velocities of 8 km/s at shallow depth. This project is an international collaboration involving researchers from Germany and France. The intellectual merit of the project proposed is to better constrain an important crust formation process by obtaining precise major, trace element and isotopic analyses of very fresh samples of this oceanic crust. The research plan include an integrated geochemical approach that will deliver detailed characterization of minerals recovered from core sections that are dominated by noritic gabbros at shallower levels, olivine-gabbros at mid levels and olivine-rich troctolites at deeper levels of the crust. The results will shed light into the geochemical and petrologic modifications that occur in the oceanic crust during magma infiltration and melt migration. The various collaborators will work at integrating their results to better understand lower crustal melt emplacement, infiltration, and interaction in this 200+ meter intrusive interval. In terms of broader impacts, the project will contribute to enhancing infrastructure for research and education at the University of Hawaii and the United States by introducing a state-of-the-art ICP-MS analytical technique developed at Max Planck Institute in Germany by the post-doctoral trainee on this proposal, Dr. Matthias Willbold. This study will also promote an international partnership between the University of Hawaii and international laboratories. Results will be disseminated in the scientific literature and will also be accessible through the IODP system of outreach programs and general education websites. Finally, the project will support the early-career development of two new NSF-supported investigators.