Collaborative Research: Building an International Component in the Aleutian-Alaska Primary Site through US Participation in Research Cruises of the German R/V Sonne

一个构造板块在另一个板块之下的俯冲是一个基本的地质过程，它对人类有许多重要的潜在影响，包括地震和火山爆发。俯冲作用在地球表面的形成中也起着关键作用，在大陆的形成中尤为重要。该项目将允许来自南卡罗来纳大学和威斯康辛大学的一组美国科学家参加德国研究船Sonne的两次研究巡航。“Sonne”号科考船将于2016年6月至7月在阿拉斯加-阿留申俯冲系统和邻近的白令海地区海底采集岩石样本。这个地区有许多地震和火山爆发，但对其早期地质历史和演变知之甚少。在这些科学巡航中收集的样本将用于了解阿留申岛弧和邻近的白令海地区在过去5000万年中的演变。研究生和本科生将参加游船活动，获得重要的航海经验。所有巡航后的数据将向公众开放。本项目主要研究三个科学主题：(1)阿留申岛弧的起源和早期发展；(2)阿留申岛弧西部活火山活动的发生和组成；(3)弧输入-北太平洋岩石圈的年龄和组成。疏浚和随后的地球化学和地质年代学研究将针对阿留申弧前的海底峡谷和其他暴露的基底结构。来自这些特征的样本将为阿留申弧形成的时间和运动学提供约束。疏浚工作还将针对阿留申群岛西部海底的火山锥和北太平洋板块下行的断裂带。这些特征的样本将用于表征阿留申弧俯冲洋壳的输入，以及它们与沿走向地球化学区域模式的关系。这些样品还将用于提高对高钙碱性西阿留申海底火山岩的认识，并从所有阿留申-阿拉斯加火山活动和全球弧火山活动来源的地球化学成分的角度来看，它们的意义。

Subduction of one tectonic plate beneath another is a fundamental geologic process, which has many important potential human impacts, including earthquakes and volcanic eruptions. Subduction also plays a key role in shaping Earth's surface, and has been particularly important in the formation of continents. This project will allow a group of U.S. scientists from the University of South Carolina and the University of Wisconsin to participate in two research cruises of the German Research Vessel Sonne. The expedition of the Research Vessel Sonne will collect rock samples from the seafloor in the Alaska-Aleutian subduction system and adjacent Bering Sea region in June-July 2016. This area has many earthquakes and volcanic eruptions, but little is known about its early geologic history and evolution. Samples collected during these scientific cruises will be used to understand the evolution of the Aleutian Island arc and adjacent Bering Sea region over the past 50 million years. Graduate and undergraduate students will participate on the cruises and gain important sea-going experience. All post-cruise data will be made available to the public.This project focuses on three scientific themes: (1) inception and early development of the Aleutian Island arc, (2) occurrence and composition of active volcanism in the western Aleutian arc, and (3) arc inputs - the age and composition of North Pacific Oceanic lithosphere. Dredging and subsequent geochemical and geochronologic studies will target submarine canyons and other exposed basement structures in the Aleutian forearc. Samples from these features will provide constraints on the timing and kinematics of Aleutian arc formation. Dredging will also target volcanic cones of the western Aleutian seafloor and fracture zones on the down-going north Pacific Plate. Samples from these features will be used to characterize inputs from subducted oceanic crust in the Aleutian arc and their relationship to regional patterns in along-strike geochemistry. These samples will also be used to provide improved understanding of the highly calc-alkaline western Aleutian seafloor volcanic rocks and their significance from the standpoint of geochemical source components for all Aleutian-Alaska volcanism, and for the source of arc volcanism globally.