Geoinformatics Phase II Project

• Title: Community Computational Platforms for Developing Three-Dimensional Models of Earth Structure, Phase II (EAR-1349180)
• Project Dates: August 15, 2014 and ends July 31, 2016
• Award Number: EAR-1349180
• PI: Thomas H. Jordan
• Co-PIs: Yifeng Cui, Po Chen, John Shaw, Jeroen Tromp

Overview:

A key problem of geoinformatics is the systematic integration of seismological and geological information into unified structural representations (USRs). The goal of this project is to develop the cyberinfrastructure needed to manage a "USR lifecycle" that can progressively and efficiently refine 3D Earth models. The lifecycle is initiated by the integration of several components into a starting model; the starting model is refined by full-3D tomographic inversion of seismic waveform data; the refined model is validated for its proposed applications and then disseminated to user communities. This new model becomes the main component of the starting model for the next lifecycle. In Phase I, we are developing three high-performance computational systems, a UCVM platform for synthesizing, comparing, and delivering Earth models and two platforms for full-3D tomography, based on the SPECFEM3D and AWP-ODC codes for anelastic wave propagation. These codes are being optimized on CPU-GPU supercomputers and used to derive new global and regional models. Our global focus is on the 3D mantle structure needed to understand geodynamics. Our regional focus is on California USRs needed for physics-based seismic hazard analysis. This proposal requests funding for Phase II, a 16-month project that has four goals: (1) Accelerate the USR lifecycle by improving the interoperability and I/O capabilities of the computational platforms. (2) Increase the scale of full-3D tomographic inversions by optimizing simulation software on heterogeneous CPU-GPU systems and by creating scientific workflows to automate full 3D tomography. (3) Deliver improved global and regional USRs by adding additional complexity to the model parameterizations (e.g., anisotropy, attenuation, small-scale stochastic heterogeneities) and by simplifying community access to these complex USRs. (4) Establish quantitative methods for evaluating USRs against standardized sets of observations. We specify milestones marking progress towards each objective; in particular, we will move the global and regional USRs developed in Phase I through another complete lifecycle by the end of this 16-month project, thereby demonstrating acceleration of the lifecycle.

Intellectual Merit :

The intellectual merit of the proposed work derives from (a) the generality of the USRs we shall construct, which are capable of representing a broad spectrum of heterogeneity controlled by a variety of geological processes, from the global scale of mantle dynamics to the small-scale, near-surface structure of sedimentary basins; (b) the power of our data assimilation approach, which employs the most advanced forms of full-3D tomography; and (c) the creation of a scientific workflow for progressive model refinement, which structures the USR lifecycle and accelerates this lifecycle through the efficient use of high-performance computing.

Broader Impacts :

The broader impacts of this project derive from its potential to provide new information to a very wide range of user communities, from basic researchers who are investigating the fundamental problems of lithospheric tectonics and mantle dynamics, to applied scientists and engineers who are trying to improve the utility of physics-based seismic forecasting and hazard analysis. Regional USRs with lateral dimensions of hundreds of kilometers will be used to simulate earthquakes, predict strong ground motions, and provide a physical basis for seismic hazard analysis. Regional USRs with lateral dimensions of thousands of kilometers will constrain the plate-tectonic processes of lithospheric creation, deformation, magmatism, and destruction. Global USRs will image the convective structure of the entire mantle and map its relationship to crustal tectonics and the geodynamo. Global and regional models will also improve imaging of seismic sources, including earthquakes and nuclear explosions. Our education and outreach plan is centered on using challenging scientific problems of compelling societal importance to engage and train a diverse STEM workforce, beginning at the undergraduate level and continuing through the post-doc level. Our objectives are to build interdisciplinary collaborations that can apply petascale technology to the most difficult problems of solid-Earth science and cross-train diverse groups of undergraduate interns and early-career scientists in geoscience and computer science.