000005444 001__ 5444
000005444 005__ 20210928200251.0
000005444 037__ $$aCTALK-2021-0077
000005444 100__ $$aCamelbeeck, Thierry
000005444 245__ $$aA new Hainaut coal area earthquake intensity attenuation model using 19th - 20th century shallow seismicity data
000005444 260__ $$c2021
000005444 269__ $$c2021-09-17
000005444 520__ $$aIn the Carboniferous coal area of the Hainaut province in Belgium, a century of shallow seismic activity occurred from the end of the 19th century until the late 20th century. This seismicity is the second largest source of seismic hazard in NW Europe. In this sequence, five seismic events (Mw~4.0), that occurred on 3 June 1911, 3 April 1949, 15 December 1965, 16 January 1966, and 28 March 1967, locally caused moderate damage to buildings to maximum intensity VII on the EMS-98 scale. For decades, the natural causality of this seismicity and its potential link with coal extraction is disputed due to uncertainties in earthquake location and depth. To tackle this discussion in the near future, we reviewed a century of intensity data collected by official macroseismic surveys held by the Royal Observatory of Belgium, press reports, and contemporary scientific studies.  In this contribution, we present methodological advances on how we updated the magnitude, epicentral intensity and location, and depth of 123 Hainaut seismic events only using macroseismic data. We discuss the impact and damage of this unique seismicity on the building infrastructure and people. Our study highlights the capability of shallow (< ~6km), small-magnitude earthquakes to generate damage. The intensity dataset shows that inside the Carboniferous coal basin (that extends from Mons to Liège) intensity attenuates much faster than in the surrounding Paleozoic Brabant and Ardenne basements due to unique characteristics of the coal basin. Using the improved intensity dataset, we modelled a new Hainaut intensity attenuation law and created relationships linking magnitude, epicentral intensity and focal depth. The new attenuation model suggests that current (international) hazard maps overestimated ground motion levels in the Hainaut area due to the use of inadequate ground motion prediction equations. Hence, the model should be used to evaluate the potential impact of current and future, e.g. geothermal energy, projects in the Hainaut area and other regions with a similar geological configuration. 
000005444 594__ $$aNO
000005444 6531_ $$aMacroseismology
000005444 6531_ $$aHistorical seismology
000005444 6531_ $$aIntensity
000005444 700__ $$aVan Noten, Koen
000005444 700__ $$aHendrickx, Marc
000005444 700__ $$aLecocq, Thomas
000005444 773__ $$t7th Geologica Belgica International Conference, Tervuren, Belgium
000005444 8560_ $$fkoen.vannoten@observatoire.be
000005444 906__ $$aContributed
000005444 980__ $$aCTALKCONT