Community Computational Platforms for Developing Three-Dimensional Models of Earth Structure

用于开发地球结构三维模型的社区计算平台

• 批准号: 1226343
• 负责人: Thomas Jordan
• 金额: $ 155万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1226343&HistoricalAwards=false
• 关键词: Community; Computational; Platforms; Developing; Three

Precise information about the structure of the solid Earth comes from seismograms recordedat the surface of a highly heterogeneous lithosphere. Full-3D tomography based on adjoint andscattering-integral methods can assimilate this information into three-dimensional models of elastic andanelastic structure. These methods fully account for the physics of wave excitation, propagation, andinteraction by numerically solving the inhomogeneous equations of motion for a heterogeneous anelasticsolid. Full-3D tomography using adjoint and scattering-integral methods requires the execution ofcomplex computational procedures that challenge the most advanced high-performance computing(HPC) systems. Current research is petascale; future research will require exascale capabilities. This project will establish an interoperable set of community computational platforms?verticallyintegrated systems of hardware, software, and wetware that will allow a significant community ofinvestigators to employ the techniques of full-3D tomography to refine Earth structures. Two tomographicplatforms will be built on highly scalable codes for solving the forward problem: the AWP-ODC 4th-order,staggered-grid, finite-difference code, which has been widely used for regional earthquake simulation andphysics-based seismic hazard analysis, and the SPECFEM3D spectral element code, which is capable of modeling wave propagation through aspherical structures of essentially arbitrary complexity on scales ranging from local to global. A third platform, based on the Unified Community Velocity Model (UCVM) software developed by the Southern California Earthquake Center (SCEC), will provide a common framework for comparing and synthesizing Earth models and delivering model products to a wide community of geoscientists. These platforms will be deployed at the NCAR-Wyoming Supercomputing Center (NWSC).

有关固体地球结构的精确信息来自高度异质岩石圈表面记录的地震图。基于伴随和散射积分方法的全 3D 断层扫描可以将这些信息吸收到弹性和非弹性结构的三维模型中。这些方法通过数值求解异质非弹性固体的非齐次运动方程，充分解释了波激发、传播和相互作用的物理原理。使用伴随和散射积分方法的全 3D 断层扫描需要执行复杂的计算程序，这对最先进的高性能计算 (HPC) 系统提出了挑战。目前的研究规模为千万亿级；未来的研究将需要百亿亿次计算能力。该项目将建立一套可互操作的社区计算平台——硬件、软件和湿件的垂直集成系统，使大量研究人员能够利用全 3D 断层扫描技术来完善地球结构。两个层析成像平台将建立在高度可扩展的代码上来解决正演问题：AWP-ODC四阶交错网格有限差分代码，已广泛用于区域地震模拟和基于物理的地震危险性分析，以及SPECFEM3D 谱元代码，能够在从局部到全局的尺度上对波通过本质上任意复杂度的非球面结构的传播进行建模。 第三个平台基于南加州地震中心 (SCEC) 开发的统一社区速度模型 (UCVM) 软件，将提供一个通用框架，用于比较和综合地球模型，并向广泛的地球科学家社区提供模型产品。这些平台将部署在 NCAR-怀俄明州超级计算中心 (NWSC)。