SI2-SSI: A Sustainable Community Software Framework for Petascale Earthquake Modeling

University Of Southern California, Los Angeles CA

Investigators

Abstract

Earthquakes have major economic and societal consequences as can be seen from the aftermath of the recent large earthquakes in Japan, Chile, and New Zealand. This multidisciplinary project, which includes both geoscientists, computer scientists, and structural engineers, integrates high-level and middle-level scientific software elements developed by the Southern California Earthquake Center (SCEC) into a software environment for integrated seismic modeling that can be used for seismic hazard analysis. The framework includes integration of community velocity models, codes for dynamic and pseudo-dynamic rupture generation, deterministic and stochastic earthquake engines, and the applications necessary to employ forward simulations in two types of inverse problems: seismic source imaging and full 3D tomography. Modifications to already existing software packages slated to be significantly enhanced in the course of the workflow will allow simulations to be run on petascale machines and allow the better managing of scientific workflows. The work also focuses on software lifecycle issues such as model formation, verification, prediction, and validation and support the use of petascale computers by earthquake scientists. The goal of the project is to facilitate the incorporation of better theory and data into computationally intensive modeling of earthquake processes. Software will be designed to interface smoothly with OpenSHA, as well as OpenSEES, PEER, and NEES. Project partners will also develop and test two computational platforms, one that will have a user-friendly interface for calculating seismographs and the other will generate large suites of simulations for a layered earthquake hazard model. Models will be validated against datasets for 13 well-recorded historic California earthquakes of magnitude 6.0 or higher. The initial API will take advantage of the asynchronous IO features of Fortran 2003 with plans for adding C/C++ and Python interfaces. All codes developed will be open-source and publicly available and software distribution will be accompanied by sample input datasets and example forecast results. Broader impacts include the development of a new generation of time-dependent earthquake forecasts to produce ground-shake hazard maps, partnership with a federal agency and the private sector. It also includes a component of student and postdoctoral training and outreach to user communities. Undergraduate interns, many of whom have historically been from groups under-represented in STEM fields, will be trained in use of the software during an 8-week summer training course.