Abstract
Seismic modelling is a useful tool for better understanding seismic behaviour in complex rock structures, but it is also a key aspect of full waveform inversion, which is a powerful technique for imaging the structure of the earth's subsurface. The great advantage of finite element methods over other wave modelling methods, like the popular finite difference method, is that it accurately captures the effect of complex topographies, such as mountainous areas and rough seabeds, without refining the grid resolution. Even so, these methods require a huge amount of computational power and making them more efficient is of great value in many industrial applications.
Topics addressed in this dissertation include: new and sharper bounds for the penalty term and time step size of the Discontinuous Galerkin method, new and significantly more efficient mass-lumped tetrahedral elements, new and efficient quadrature rules for evaluating the stiffness matrix of these mass-lumped elements, stability properties of a basic local time-stepping algorithm, and a dispersion analysis and comparison of multiple finite element methods.
Overall, the finite element methods and algorithms presented in this dissertation allow for a much faster modelling of seismic waves. This is especially true for the new mass-lumped finite elements, which in some cases result in a speed of a factor 10 compared to other finite element methods. These improvements make the use of finite element methods much more attractive for geophysical applications or other industrial applications that involve solving wave propagation problems.
| Language | English |
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| Supervisors/Advisors |
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| Award date | 21 Sep 2018 |
| Place of Publication | Enschede |
| Publisher | |
| Print ISBNs | 978-90-365-4613-3 |
| Electronic ISBNs | 978-90-365-4613-3 |
| DOIs | |
| Publication status | Published - 2018 |
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Keywords
- Finite Element Method
- Wave Equation
- Seismic Modelling
Cite this
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Finite Element Methods for Seismic Modelling. / Geevers, Sjoerd .
Enschede : University of Twente, 2018. 178 p.Research output: Thesis › PhD Thesis - Research UT, graduation UT › Academic
TY - THES
T1 - Finite Element Methods for Seismic Modelling
AU - Geevers, Sjoerd
PY - 2018
Y1 - 2018
N2 - In this dissertation, new and more efficient finite element methods for modelling seismic wave propagation are presented and analysed. Seismic modelling is a useful tool for better understanding seismic behaviour in complex rock structures, but it is also a key aspect of full waveform inversion, which is a powerful technique for imaging the structure of the earth's subsurface. The great advantage of finite element methods over other wave modelling methods, like the popular finite difference method, is that it accurately captures the effect of complex topographies, such as mountainous areas and rough seabeds, without refining the grid resolution. Even so, these methods require a huge amount of computational power and making them more efficient is of great value in many industrial applications.Topics addressed in this dissertation include: new and sharper bounds for the penalty term and time step size of the Discontinuous Galerkin method, new and significantly more efficient mass-lumped tetrahedral elements, new and efficient quadrature rules for evaluating the stiffness matrix of these mass-lumped elements, stability properties of a basic local time-stepping algorithm, and a dispersion analysis and comparison of multiple finite element methods.Overall, the finite element methods and algorithms presented in this dissertation allow for a much faster modelling of seismic waves. This is especially true for the new mass-lumped finite elements, which in some cases result in a speed of a factor 10 compared to other finite element methods. These improvements make the use of finite element methods much more attractive for geophysical applications or other industrial applications that involve solving wave propagation problems.
AB - In this dissertation, new and more efficient finite element methods for modelling seismic wave propagation are presented and analysed. Seismic modelling is a useful tool for better understanding seismic behaviour in complex rock structures, but it is also a key aspect of full waveform inversion, which is a powerful technique for imaging the structure of the earth's subsurface. The great advantage of finite element methods over other wave modelling methods, like the popular finite difference method, is that it accurately captures the effect of complex topographies, such as mountainous areas and rough seabeds, without refining the grid resolution. Even so, these methods require a huge amount of computational power and making them more efficient is of great value in many industrial applications.Topics addressed in this dissertation include: new and sharper bounds for the penalty term and time step size of the Discontinuous Galerkin method, new and significantly more efficient mass-lumped tetrahedral elements, new and efficient quadrature rules for evaluating the stiffness matrix of these mass-lumped elements, stability properties of a basic local time-stepping algorithm, and a dispersion analysis and comparison of multiple finite element methods.Overall, the finite element methods and algorithms presented in this dissertation allow for a much faster modelling of seismic waves. This is especially true for the new mass-lumped finite elements, which in some cases result in a speed of a factor 10 compared to other finite element methods. These improvements make the use of finite element methods much more attractive for geophysical applications or other industrial applications that involve solving wave propagation problems.
KW - Finite Element Method
KW - Wave Equation
KW - Seismic Modelling
U2 - 10.3990/1.9789036546133
DO - 10.3990/1.9789036546133
M3 - PhD Thesis - Research UT, graduation UT
SN - 978-90-365-4613-3
PB - University of Twente
CY - Enschede
ER -