Collaborative Research: Investigating Initiation and History of the Aleutian Arc and Composition and Significance of North Pacific Seafloor via Dredge Samples from the R/V Sonne

俯冲作用是一个基本的构造过程，它决定了地球的物理和化学演化，并具有许多重要的潜在人类影响，包括地震和火山灾害，以及矿产资源，这些都是俯冲岩浆作用的常见产物。因此，与俯冲有关的过程是地球科学中广泛关注和广泛研究的主题。尽管对阿拉斯加-阿留申俯冲系统进行了近一个世纪的研究，但仍有几个关键问题没有得到解答，包括俯冲带是如何以及何时形成的，以及俯冲的太平洋板块在多大程度上促进了阿拉斯加-阿留申火山下岩浆的形成。这个项目将允许来自南卡罗来纳大学和威斯康星大学麦迪逊分校的一组美国科学家精确地确定阿留申弧形成的时间，并描述进入和从这个活跃的火山弧喷发出来的产品。这是一项来自德国、俄罗斯和美国的研究生、本科生、博士后和研究人员的合作努力。该项目的所有数据将向公众开放。该项目有两个广泛相关的主题：1)限制俯冲开始的时间和阿留申弧的早期演化；2)表征阿留申弧和堪查加弧的俯冲输入，并将其与控制弧岩浆形成的过程联系起来。作为德国-俄罗斯BERING项目的一部分，来自德国R/V Sonne的SO249远征队的样品分析将提供阿留申弧形成时间和早期弧产物的地球化学限制。该项目还将获取靠近阿留申弧西部的北太平洋海底样本的地球化学数据，包括皇帝海山北部东部和西部的地点。该研究将有助于更好地理解俯冲输入与火山输出之间的地球化学联系，并将为阿留申群岛和堪察加半岛的弧岩浆成因提供新的约束条件和显著改进模型。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。

Subduction is a fundamental tectonic process that shapes the Earth's physical and chemical evolution and has many important potential human impacts, including seismic and volcanic hazards, as well as mineral resources, which are common products of subduction magmatism. As a result, subduction-related processes are the subject of broad public interest and widespread investigation in the geosciences. Despite almost a century of research on the Alaska-Aleutian subduction system, several key questions remain unanswered including how and when the subduction zone was formed and to what extent the subducting Pacific plate contributes to the creation of magma generated beneath Alaska-Aleutian volcanoes. This project will allow a group of U.S. scientists from the University of South Carolina and the University of Wisconsin-Madison to precisely determine the timing of Aleutian arc formation and to characterize the products that are entering and have erupted from this active volcanic arc. This is a collaborative effort involving graduate and undergraduate students, post-docs, and researchers from Germany, Russia and the United States. All data from this project will be made available to the public. The project has two broadly related themes: 1) Constraining the timing of subduction initiation and early evolution of the Aleutian arc, and 2) Characterizing subduction inputs to both the Aleutian and Kamchatka arcs and relating them to the processes controlling arc magma formation. Analyses of samples from Expedition SO249 of the German R/V Sonne as part of the German-Russian BERING project will provide constraints on the timing of Aleutian arc formation and the geochemistry of the early arc products. The project will also obtain geochemical data for north Pacific seafloor samples adjacent to the western Aleutian arc, including sites both east and west of the northern Emperor seamounts. This study will help better understand geochemical linkages between subduction input and volcanic output, and will provide new constraints and significantly improve models of arc magma genesis for the Aleutians and Kamchatka.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.