Full-wave Moment Tensor and Tomographic Inversions Based on 3D Strain Green Tensor
Final rept. 28 Feb 2008-31 Dec 2009
SCIENCE APPLICATIONS INTERNATIONAL CORP (SAIC) ARLINGTON VA
Pagination or Media Count:
We developed a unified source moment tensor and tomographic inverse method based on finite difference simulations of wave propagation at local to teleseismic distances. The new method accounts for complex wave propagation in three-dimensional 3D earth, linearizes the inverse problem by iteratively updating the earth model, and provides an accurate way to integrate body- and surface-wave observations. The finite-difference methods developed to date make it possible to construct hierarchical FD-SGT databases efficiently and with great flexibility. The spherical finite-difference method is well suited for regional and global wave propagation, while the finite-difference method with boundary conforming grids that follow topography provides higher accuracy at local and near regional scales. The self-consistent FD-SGT databases constructed from finite-difference simulations of wave propagation in full-wave tomographic models can be used to determine the moment tensors within minutes after a seismic event, making it possible for real time monitoring using 3D models.
- Theoretical Mathematics