Geodynamics of the Americas

北美西部和南美是山脉、地震和火山聚集的地区，这些地区是由直接发生在近海的板块构造过程造成的。在这里，海洋板块下沉到大陆下方的地球上，这一过程被称为俯冲。我的研究旨在了解俯冲、地球内部动力学和地球表面观测到的地质之间的关系。拟议的研究侧重于南北美洲西部地质的两个方面：(1)造山——我和我的学生想了解美国西部的拉拉米德造山运动（超过5000万年前）和南美洲现代安第斯山脉中部的发展。我们将建立计算机模型来研究地壳变形和俯冲力之间的联系。我们感兴趣的是测试是否需要一个不寻常的俯冲环境来产生Laramide变形，以及山带中的小规模过程（如地表侵蚀）是否会影响其大规模演化。(2)俯冲动力学——地幔（地壳以下区域）的俯冲和流动直接影响地球的温度结构，从而控制变形和火山活动。利用最先进的计算机程序，我的研究小组将开发3D模型，以了解俯冲带的地幔流动和大陆温度，重点关注与复杂板块几何形状和海洋板块中空洞存在相关的3D效果。计算机模型使我们深入了解了影响北美和南美西部地质演化的因素。它们还提供了有关地球内部温度和应力的信息，这些信息对于评估地震危险、火山活动、碳氢化合物潜力和地热能非常重要。

Western North and South America are regions with mountains, earthquakes, and volcanoes that result from plate tectonic processes occurring immediately offshore. Here, oceanic plates descend into the Earth below the continent, a process known as subduction. My research aims to understand the relationship between subduction, the dynamics of the Earth's interior and the geology that is observed at the Earth's surface. The proposed research focuses on two aspects of the geology of western North and South America:(1) Mountain-building - my students and I would like to understand the development of the Laramide Orogeny (over 50 million years ago) in the western United States and the modern Central Andes of South America. We will build computer models to study links between crustal deformation and subduction forces. We are interested in testing whether an unusual subduction environment was needed to produce Laramide deformation and if small-scale processes in a mountain belt (such as surface erosion) affect its large-scale evolution.(2) Subduction dynamics - subduction and flow of the mantle (the region below the Earth's crust) directly affect the temperature structure of the Earth, which then controls deformation and volcanism. Using state-of-the-art computer programs, my research group will develop 3D models to understand mantle flow and continental temperatures at subduction zones, focusing 3D effects associated with complex plate geometries and the presence of a hole in the oceanic plate.The computer models yield insight into the factors that have shaped the geological evolution of western North and South America. They also provide information about temperatures and stresses within the Earth, which are important for the assessment of seismic hazard, volcanism, hydrocarbon potential and geothermal energy.