This thesis investigates earthquake ground motion in Belgium, with the objective of improving seismic hazard assessment in a low-to-moderate seismicity region. The work is based on three main contributions: the development of a high-quality ground-motion database (BELSHAKE), the analysis of high-frequency attenuation using the kappa parameter, and the evaluation of ground-motion models (GMMs).
The BELSHAKE database provides a systematically processed and quality-controlled dataset of weak to moderate earthquake recordings, enabling consistent analysis of ground-motion characteristics. Using this dataset, high-frequency attenuation is quantified through, leading to the estimation of site-specific and regional attenuation parameter, and revealing spatial variability linked to Belgian crustal structure.
Finally, a wide range of GMMs is evaluated against the BELSHAKE data using multiple statistical measures. The results highlight the importance of regional calibration, as many models developed in high-seismicity regions tend to overestimate ground motions for small events. A subset of models is identified that best represents observed ground motion in Belgium.
Together, these contributions provide a consistent framework and essential input for improving seismic hazard assessment and reducing uncertainty in Belgium.
Membres du jury :
- Dr. Kris Vanneste (Royal Observatory of Belgium) - Promoteur
- Prof. João Saraiva Esteves Pacheco de Almeida (UCLouvain) - Promoteur
- Prof. Paul Fisette (UCLouvain)- Président
- Prof. Hadrien Rattez (UCLouvain) - Secrétaire
- Dr. Thierry Camelbeeck (Royal Observatory of Belgium)
- Dr. Paola Traversa (Electricite de France - EDF)
- Dr. Helen Crowley (Global Earthquake Model – GEM)
- Prof. Hervé Degée (Hasselt university)
Microsoft Teams meeting: https://teams.microsoft.com/meet/341264796579066?p=jiC54lnYicPw6sNw03
Meeting ID: 341 264 796 579 066
Passcode: kt9JY3MS
