CAREER: Using Upper Mantle Circulation Models to Evaluate the Role of the Asthenosphere: Tectosphere Contrast and Subduction Dynamics for Global Plate Tectonics

利用上地幔环流模型评估软流圈的作用：构造圈对比和全球板块构造的俯冲动力学研究重点是具有真实板块边界的全球数值对流模型、流变学和热化学对比以及改进的地震学约束。地幔内部的力分配影响着板块内和板块边界的地震构造，通过力学模拟研究地幔系统是理解板块运动和地质记录构造事件的关键。工作分为两个研究项目，这两个项目相互关联，具有很强的教育成分。项目一使用循环计算对地震学数据进行反演，以评估岩石蠕变行为的观测结果和实验室结果所需的粘度变化范围（粘性层析成像）。项目二将断层边缘纳入全球模型（板、龙骨和板块）。板块驱动和控制板块的速度，因此需要将板块边界更现实地纳入全球模型。它评估了板块和海沟运动相对于构造圈的程度：软流圈对比控制全球动力学，如位势场和地震耦合。研究和教育工作的统一主题是利用地震学和矿物物理学衍生的全球流动模型和结构。目的是建立一种新的地幔环流模型，阐明软流圈在塑造板块构造和组织深部地球结构中的作用。本计划的教学工作主要集中在一门新的数值方法课程的教材和两个用于探索地幔流和层析成像的固体地球软件模块，这两个模块都是公开开发和免费共享的。其目标是通过实验改进研究工具来学习。这些工具是可定制的，因此它们对一般的本科和研究生课程都很有用。努力加强学生解决相互关联的问题所需的定量技能；适用于研究生解决地幔动力学中的突出问题，以及在行星环境挑战中需要做出明智选择的非专业人员。在传统的科学传播手段受到过度限制的领域，这项工作有助于更透明地展示学科研究成果。通过提供定量分析方面的基础训练和新地震和地球动力学模型共享的实例，跨学科约束的稳健性更容易评估。如果我们要加速在板块构造学和地球科学的复杂问题上取得进展，这是至关重要的。

Using upper mantle circulation models to evaluate the role of the asthenosphere:tectosphere contrast and subduction dynamics for global plate tectonicsResearch focuses on global, numerical convection models with realistic plate boundaries, rheological and thermo-chemical contrasts, and improved constraints from seismology. The force partitioning in the mantle affects intraplate and plate boundary seismo-tectonics, and studying the mantle system by mechanical modeling holds the key to understanding plate motions and geologically recorded tectonic events. Efforts are divided into two research projects which are interrelated and have strong educational components. Project one uses circulation computations for an inversion of seismology data to evaluate the range of viscosity variations that are required by observables and laboratory results on the creep behavior of rocks (viscous tomography). Project two incorporates faulted margins into a global model (slabs, keels, and plates). Slabs drive and control the speed of the plates, and a more realistic inclusion of plate boundaries into global models is needed. It is evaluated to what degree slabs and trench motions vs. the tectosphere: asthenosphere contrast control global dynamics such as geopotential fields and seismic coupling. The unifying theme of research and educational efforts is the use of global flow models and structure derived from seismology and mineral physics. The goal is to arrive at a new kind of mantle circulation model that elucidates the roles of the asthenosphere in shaping plate tectonics and organizing deep Earth structure. The educational efforts in this project focus on course material for a new numerical methods class and two solid earth software modules for exploring mantle flow and tomography, both openly developed and freely shared. The goal is to allow learning through experimentation with modified research tools. Those tools are customizable so that they are useful for both general undergrad and graduate classes. Efforts strengthen the quantitative skills of students needed to tackle interconnected problems; useful for grad students to solve outstanding questions in mantle dynamics, and for non-specialists who need to make informed choices during planetary environmental challenges. Work contributes to a more transparent representation of disciplinary research results where traditional means of scientific communication are becoming unduly limiting. By providing both fundamental training in quantitative analysis and examples for novel seismological and geodynamical model sharing, the robustness of extra-disciplinary constraints are easier to evaluate. This is crucial if we are to accelerate progress on complex problems in plate tectonics and earth science in general.