Seismic waveform tomography on continental scales based on the spectral-element and adjoint methods
Final Report Abstract
Our work demonstrates the feasibility of 3-D full wave-form inversion on continental scales. The approach uses (1) a spectral-element solver that combines accuracy, speed and algorithmic simplicity; (2) a long-wavelength equivalent crustal model for computational efficiency; (3) an integration scheme for the regular and adjoint wavefields; (4) a rapidly converging conjugate-gradient algorithm based on the the adjoint approach. Our tomographic results of Australasian region agree with earlier seismic studies on heterogeneity length scales greater than 500 km. The long- and short-wavelength structures can be interpreted geodynamically in terms of regional tectonic processes within the lithosphere (i.e. cratonic structures), and mantle flow in the upper mantle with an emphasis on channelised flow in a shallow asthenosphere. Future work should focus on upper mantle imaging in other regions, and on the explicit linking of the tomographic structure to geodynamic flow models.
Publications
- 2009. Full waveform inversion for structural and source parameters PhD Thesis, LMU Munich
Andreas Fichtner
- 2009; Full waveform tomography for upper-mantle structure in the Australasian region using adjoint methods; Geophysical Journal International, 179, 1703-1725
Andreas Fichtner, Brian L. N. Kennett, Heiner Igel, Hans-Peter Bunge
- 2009; Simulation and inversion of seismic wave propagation on continental scales based on a spectral-element method; Journal of Numerical Analysis, Industrial and Applied Mathematics, 4, 11-22
Andreas Fichtner, Heiner Igel, Hans-Peter Bunge, Brian L. N. Kennett
- 2010; Advances in modelling and inversion of seismic waveforms in High Performance Computing in Science and Engineering , 3, 293-306. Spinger-Verlag, Berlin Heidelberg
Verena Hermann, Nguyen Dinh Pham, Andreas Fichtner, Simon Kremers, Hans-Peter Bunge, Heiner Igel
- 2010; Full waveform tomography for radially anisotropic structure: New insights into present and past states of the Australasian upper mantle; Earth and Planetary Science Letters, 290, 270-280
Andreas Fichtner, Brian L. N. Kennett, Heiner Igel, Hans-Peter Bunge
- 2011; Developments in full seismic waveform tomography on continental scales; Mitteilungen der Deutschen Geophysikalischen Gesellschaft, 1/2011, 15-23
Andreas Fichtner, Paul Kaeufl, Brian L. N. Kennett, Jeannot Trampert, Heiner Igel, Hans-Peter Bunge