The macroseismic field of the Roermond earthquake of April 13, 1992, has been compared with those of large historical earthquakes (ML ≥ 5.5) in the Lower Rhine Embayment and its vicinity: those of Düren (1755 ,1756), Tollhausen (1878), North-Brabant(1932)

Abstract

The macroseismic field of the Roermond earthquake of April 13, 1992, has been compared with those of large historical earthquakes (ML ≥ 5.5) in the Lower Rhine Embayment and its vicinity: those of Düren (1755 ,1756), Tollhausen (1878), North-Brabant(1932) and Euskirchen (1951). The historical earthquakes were reconstructed and analysed mainly on the basis of contemporary historical documents. All investigated earthquakes caused at least moderate damage in their epicentral regions. While the earthquakes of Düren (1756) and Tollhausen (1878) reached the epicentral intensity VIII, the others produced only epicentral intensities between VII and VII-VIII. The mean value of the absorption coefficient α =0.002 ± 0.001 km-1 was calculated from the intensity attenuation curves. The macroseismic focal depths of the Tollhausen (1878), North-Brabant(1932) and Euskirchen (1951) earthquakes range from 9 to 8 km, whereas the Düren (1755,1756) and Roermond (1992) earthquakes occurred at a depth range from 14 to 18 km. The strongest event in historical time was the Düren (1756) earthquake. Its macroseismically determined local magnitude ML = 6.1 was slightly larger than the local magnitude of the Roermond earthquake ML = 5.9.