Camelbeeck, Thierry ; Knuts, Elisabeth ; Alexandre, Pierre ; Lecocq, Thomas ; Van Noten, Koen

published in Journal of Seismology (2021)

Abstract: We present a comprehensive study of the 23 February 1828 earthquake that caused severe damage in the central part of the present Belgian territory. We synthesised and critically reassessed the information provided by contemporaneous scientific studies and newspapers of the Low Countries. In addition, a systematic survey of official, private, and religious historical sources was undertaken to improve our knowledge of the earthquake effects in the most affected region. In total, we collected information for 185 localities in the present territory of Belgium, France, Germany, The Netherlands, Grand Duchy of Luxembourg, and southern England. The complex spatial repartition of earthquake testimony locations is related to the population density, the types of historical sources, and the regional geological context. Our 1828 earthquake intensity analysis demonstrates that the shaking strength diminished more slowly along the WSW-ENE strike in this part of the Brabant Massif compared to the surrounding Rhenish Massif and Paris Basin. Moreover, the northward increasing thickness of sediments on top of the Brabant Massif controlled the observed strong intensity attenuation. Using the intensity dataset, we located the earthquake at 50.70° N and 5.12° E, with uncertainty around 10 km. The magnitude is estimated as MW = 5.1 ± 0.3 and the average focal depth optimising the location inversion is 10 km with a possible range between 3 and 15 km. Our study illustrates the benefit of historical seismicity studies on the knowledge of the impact of rare destructive earthquakes in stable continental regions like Western Europe.

Keyword(s): Historical seismicity ; Nineteenth century ; Intensity analysis ; Damage
DOI: 10.1007/s10950-020-09977-6
Funding: BELSPO/MO/33/010; ROB supplementary researchers