Collaborative Research: Structure and Composition of Oceanic Lithosphere and the Lithosphere/Asthenosphere Boundary

岩石圈是地球的岩石外壳。岩石圈“板块”带着大陆在地球上漂移，大地震和火山爆发发生在板块相互作用的地方。因此，了解岩石圈对我们了解地球如何运作至关重要。海洋岩石圈覆盖了地球的70%，是我们了解全球地球动力学和板块构造的核心，但我们对其特征（包括组成和厚度）以及控制它们的因素的了解很少。地球的地震和电学性质的变化是成分变化的指示。这个项目的目的是使用最新的地震和电磁方法来解决关于位于太平洋盆地下面的岩石圈的两个基本问题：什么因素控制岩石圈的地震结构，以及什么定义了岩石圈的基底？这项工作的更广泛的影响包括提高对影响火山爆发、大地震和海啸的岩石圈组成等因素的理解，这些因素威胁着阿拉斯加、太平洋西北部和环太平洋其他地区的人口稠密地区。

TThe lithosphere is the Earth's rocky outer shell. Lithospheric 'plates' drift over the Earth, carrying the continents, and large earthquakes and volcanic eruptions occur where the plates interact. Hence, understanding the lithosphere is central to our understanding of how the Earth works. The oceanic lithosphere, which covers some 70% of the Earth, is central to our understanding of global geodynamics and plate tectonics, but our understanding of its character (including composition and thickness) and the factors that control them is poor. Variations of seismic and electrical properties of the Earth are indicators of compositional variations. The aim of this project is to use the most up-to-date seismic and electromagnetic methods to address two fundamental questions about the lithosphere that lies beneath the Pacific basin: What factors control the seismic structure of the lithosphere, and what defines the base of the lithosphere? The broader impacts of this work include improved understanding of factors such as the composition of the lithosphere that affect volcanic eruptions, great earthquakes and tsunamis that threaten heavily populated areas in Alaska, the Pacific Northwest, and elsewhere around the Pacific Rim.