Towards Forward and Inverse Earthquake Modeling on Petascale Computers

Abstract

We will discuss the work of the Quake Project on large-scale forward and inverse earthquake modeling. After some initial comments on forward modeling, we will focus on the inverse problem of estimating the earth model from observations of ground motion of past earthquakes. We will discuss such compounding issues as extreme large scale, ill-posedness, discontinuous solutions, multigrid optimization preconditioners, nonlinear convergence difficulties, and multiple local minima, as well as techniques for addressing them on multi-thousand processor terascale supercomputers. We will end with a discussion of some outstanding challenges and the prospects for earthquake inversion to frequencies of engineering interest on petascale-class computers.