Details of the abstract
| Title of paper | Time-dependent adaptive mesh refinement for 3D forward modelling of transient electromagnetic fields in volcanic environments including topography |
| List of authors | Schneider, C., Spitzer, K., Hort, M. |
| Affiliation(s) | TU Bergakademie Freiberg, TU Bergakademie Freiberg, Universität Hamburg |
| Summary | Numerical forward modelling of transient electromagnetic (TEM) fields in topographically demanding terrain is a rather challenging task but inevitable to identify reasonable measurement configurations and to correctly interpret acquired field data when investigating mountainous regions. Since the propagating electromagnetic fields change with time and space, an adaptively refined grid would ideally be time-dependent, too. Generating large unstructured tetrahedral grids tailored manually to each specific time-step is, however, very time consuming. Moreover, the system matrix also changes with time causing additional numerical work in the solution process. We tackle both problems by using a very efficient Krylov-subspace method which projects the system matrix onto a low-dimensional space and, therefore, enables us to evaluate the solution for any given time. Additionally, we propose an adaptive approach including hanging edges within our modelling domain. With this, an initial mesh is refined according to the requirements of the propagating electromagnetic field. The development is driven by the application of TEM at volcanic sites. There is an enormous volcanological interest in magmatic pathways and hydrothermal systems within volcanic structures aiming to understand processes occurring prior to a volcanic eruption. Therefore, we apply our TEM simulation routine to a model of Stromboli volcano, Italy, created from a digital elevation model (DEM). |
| Session Keyword | 2.0 Theory, Modelling and Inversion |
| File upload |
2.0_time-dependent_adaptive_m_spitzer.pdf
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