Seismotectonic significance of the 2008-2010 Walloon Brabant seismic swarm
The small town of Court-Saint-Etienne in Walloon Brabant was struck by a low-magnitude (ML -0.7 to ML 3.2) earthquake sequence from 12 July 2008 until 18 January 2010. 239 events were recorded by the Belgian permanent seismic network that was improved by a local seismic network installed around Court-Saint-Etienne and Ottignies. The seismic sequence was reported regularly in the Belgian media during these 1.5 years as 60 of the 239 events were felt by the local population.
The small town of Court-Saint-Etienne in Walloon Brabant was struck by a low-magnitude (ML -0.7 to ML 3.2) earthquake sequence from 12 July 2008 until 18 January 2010. 239 events were recorded by the Belgian permanent seismic network that was improved by a local seismic network installed around Court-Saint-Etienne and Ottignies. The seismic sequence was reported regularly in the Belgian media during these 1.5 years as 60 of the 239 events were felt by the local population.
In collaboration with Anjana K. Shah (USGS), Dr. Koen Van Noten, Dr. Thomas Lecocq and Dr. Thierry Camelbeeck (ROB) found the causative source of these earthquakes using a multidisciplinary geological, seismological and geophysical approach. By relocating all individual earthquakes, Van Noten and colleagues demonstrated that the seismic activity of these earthquakes occurred along a single, vertical blind fault structure at a depth between 5 km and 7 km below the hamlet of Faux (see Figure)(Walloon Brabant Province. The fault developed in the ~500 million year old, clayey Mousty rock formation of the Brabant Massif.
In collaboration with Anjana K. Shah (USGS), Dr. Koen Van Noten, Dr. Thomas Lecocq and Dr. Thierry Camelbeeck (ROB) found the causative source of these earthquakes using a multidisciplinary geological, seismological and geophysical approach. By relocating all individual earthquakes, Van Noten and colleagues demonstrated that the seismic activity of these earthquakes occurred along a single, vertical blind fault structure at a depth between 5 km and 7 km below the hamlet of Faux (see Figure)(Walloon Brabant Province. The fault developed in the ~500 million year old, clayey Mousty rock formation of the Brabant Massif.
By analysing the variation of magnetic properties of the surrounding rock formations at depth, these authors moreover discovered that this fault is only present at depth and does not continue towards surface to have a surface expression. The results of this BELSPO MO-33-028 project published in Tectonophysics and the authors were congratulated by the journal editor because of the excellence and clear representation of their work.
By analysing the variation of magnetic properties of the surrounding rock formations at depth, these authors moreover discovered that this fault is only present at depth and does not continue towards surface to have a surface expression. The results of this BELSPO MO-33-028 project published in Tectonophysics and the authors were congratulated by the journal editor because of the excellence and clear representation of their work.
Paper on the Brabant Walloon seismic swarm:
Paper on the Brabant Walloon seismic swarm:
Van Noten, K., Lecocq, T., Shah, A. & Camelbeeck, T. 2015. Seismotectonic significance of the 2008-2010 Walloon Brabant seismic swarm in the Brabant Massif (Belgium). Tectonophysics, 656, 20-38. doi:10.1016/j.tecto.2015.05.026
Conference presentations on the Brabant Walloon seismic swarm
Conference presentations on the Brabant Walloon seismic swarm
- Van Noten, K. & Lecocq, T. 2016. Continuous H/V Spectral Ratio Analysis of Ambient Noise: a necessity to understand microzonation results obtained by mobile stations. Geophysical Research Abstracts 18, EGU2016-4609, session SM2.2/NH4.13, 17-22 April 2016, Vienna, Austria.
- Consentino, B.C., Van Noten, K., Sintubin, M. 2016. Macroseismic intensity assessment of the 2008-2010 Walloon Brabant Seismic Swarm (Belgium) by a griell procedure. 48th Congresso Brazileiro de Geologia, 9-13 October 2016, Porto Alegre, Brazil.
- Van Noten, K., Lecocq, T., Meyer, L., Molron, J. & Camelbeeck, T. 2015. Continuous H/V Spectral Ratio Analysis of Ambient Noise Recorded by Stationary Seismic Stations to Improve Microzonation Results Obtained by Mobile Stations. American Geophysical Union, AGU2015-NS41B-1936, 14-18 December 2015, San Francisco, USA.
- Van Noten, K., Lecocq, T., Molron, J., Camelbeeck, T. & Van Camp, M. 2015. Shear wave velocity estimation of cover sediments by seismic array measurements. Geophysical Research Abstracts 17, EGU2015-7445, session SM4.1, 12-17 April 2015, Vienna.
- Van Noten, K., Lecocq, T., Shah, A. & Camelbeeck, T. 2015. Seismotectonic significance of the 2008-2010 seismic swarm in the Brabant Massif (Belgium). Geophysical Research Abstracts 17, EGU2015-4229, session TS4.1/SM6.4, 12-17 April 2015.
- Van Noten, K., Lecocq, T., Shah, A. & Camelbeeck, T. 2015. Deducing the seismotectonic significance of the 2008-2010 seismic swarm in the Brabant Massif by aeromagnetic bandpass filtering (Belgium). Tectonic Studies Group AGM, Edinburgh, UK.
- Van Noten, K., Lecocq, T., Watlet, A., Camelbeeck, T., 2014. Modelling sediment thickness for site-effect characterisation using H/V spectral ratio analysis and electrical resistivity tomography. Geophysical Research Abstracts 16, EGU2014-13252, session SM2.3, 27 april - 2 May 2014.
- Van Noten, K., Lecocq, T. & Camelbeeck, T. 2013. Using H/V Spectral Ratio Analysis to Map Sediment Thickness and to Explain Macroseismic Intensity Variation of a Low-Magnitude Seismic Swarm in Central Belgium. American Geophysical Union, AGU2013-S53B-2406, 9-13 December 2013, San Francisco, USA.
- Van Noten, K., Lecocq, T., Vleminckx, B., Camelbeeck, T., 2013. Macroseismic investigation of the 2008-2010 low magnitude seismic swarm in the Brabant Massif, Belgium. The link between macroseismic intensity and geomorphology. Geophysical Research Abstracts 15, EGU2013-4923, session SM2.8, 7-12 april 2013, Vienna.
- Van Noten, K., Lecocq, T. & Camelbeeck, T. 2013. The tectonic significance of the 2008-2010 seismic swarm in the Brabant Massif, Belgium. DRT2013, 16-18 September 2013, Leuven, Belgium
- Van Noten, K., Lecocq, T, Verbeeck, K., Vanneste, K. & Camelbeeck, T. 2012. Modelling the palaeotopography of the Brabant Massif: a necessity to understand the site effects of the 2008-2011 seismic activity in the Brabant Walloon. 4th International Geologica Belgica Meeting, 11-14 September 2012, Brussels, Belgium