CAREER: Rheology of Materials of Earth's Mantle: High-end Computational/Visualization Research and Education

该提案旨在系统地应用计算机和材料科学的思想和技术来解决地球材料基本问题的理论研究中的挑战性问题。其中一个问题是了解地幔组成材料在地球物理相关压力和温度条件下的流变特性，而这些条件仍然是实验无法达到的。流变学是一个关键因素，它对地震观测和其他来源所暗示的复杂地幔动力学有很大影响。大规模原子模拟将结合第一原理量子力学 (QM)、经典分子动力学 (MD) 和混合 QM/MD 方法在大规模并行机器上进行。 这些模拟将预测主要硅酸盐和氧化物地幔矿物的几个关键的流变学相关特性和过程，包括点缺陷、位错和相关的长程机械现象，以及多晶矿物在各向异性应力下的变形。由此产生的大量多元数据集将在沉浸式交互式环境中可视化，以深入了解矿物的复杂机械行为。 上述跨学科研究活动将融入教学/学习/培训活动。其中包括培训具有计算和地球材料科学专业知识的新一代学生（通过计算机和地球科学双学位研究生课程），开发基于访问网格的远程教学/学习环境（包括路易斯安那州的少数族裔机构），并为代表性不足的群体组织计算科学研讨会和狂欢节会议，这些研讨会此前已在路易斯安那州立大学（LSU）组织过。 这些活动的成功实施将吸引学生和教师的广泛实质性参与，其中包括那些来自代表性不足群体的学生和教师，参与地球物理学和信息技术领域的研究和教育。 该项目将利用路易斯安那州立大学最近收购的世界一流的 1024 处理器 Linux 集群、Immersadesk 虚拟现实和 Access Grid 设施。 --

This proposal aims to systematically apply ideas and techniques of computer and materials sciences to challenging problems in the theoretical investigation of fundamental issues of Earth materials. One such issue is to understand the rheological properties of the component materials of Earth's mantle at geophysically relevant pressure and temperature conditions that are still experimentally inaccessible. Rheology is a key factor, which has strong influence on the complicated mantle dynamics implied by seismological observations and other sources. Large-scale atomistic simulations will be performed on massively parallel machines using a combination of first-principles quantum mechanical (QM), classical molecular dynamics (MD) and hybrid QM/MD approaches. The simulations will predict several crucial rheology-related properties and processes in major silicate and oxide mantle minerals, including point defects, dislocations and associated long-range mechanical phenomena, and deformation of polycrystalline minerals under anisotropic stresses. The resulting massive multivariate datasets will be visualized in an immersive and interactive environment to gain insight into complex mechanical behavior of minerals. The aforementioned interdisciplinary research activities will be integrated into teaching/learning/training activities. They include training a new generation of students with expertise in computational and Earth materials sciences (through a dual-degree graduate program in computer and geosciences), developing an Access Grid-based remote teaching/learning environment (encompassing minority institutions in Louisiana) and organizing computational science workshop for underrepresented groups and Mardi Gras conference that have previously been organized at Louisiana State University (LSU). The successful execution of these activities will have broad substantive involvement of students and faculty including those from underrepresented groups in research and education at the interface of geopysics and information technology. The project will exploit the world-class 1024-processor Linux cluster, Immersadesk virtual reality, and Access Grid facilities recently acquired by LSU. --