An Earthquake Catalog for the Northern Rhine Area, Central Europe (1975-2002)

Abstract

On 14 March 1951 an earthquake of local magnitude 5.1 (Hinzen and Oemisch, 2001) with a hypocenter near the town of Euskirchen, Germany caused injuries and property damage estimated at several million Deutsche Mark (DM). In the nearby town of Arloff, eight schoolchildren were injured by falling roof tiles and chimney parts ( Kolner Stadtanzeiger , 1951). Since no local seismic monitoring was available in this area, a seismic station (BNS) to monitor seismic activity in the northern Rhine area was promptly established by the University of Cologne (Ahorner, 1997). In the mid-1970's, the single-station BNS was upgraded to a network for routine surveillance of seismicity in the Northern Rhine Area (NRA). The current Bensberg network (BENS) consists of twenty short-period seismic stations as shown in Figure 1 (not all station codes are annotated). The Northern Rhine Area is part of the European rift system, which developed in the middle to late Eocene. The rift system extends over 1,100 km starting at the Rhone Valley and the Upper Rhine graben (URG) to the south, extending to the Middle Rhine Area and Lower Rhine embayment (LRE) to the northwest, and continuing to the North Sea (Figure 1) (Ziegler, 1982; Meyer, 1988; Geluk et al. , 1994; Ziegler, 1994). The URG, the Hessiangraben, and the LRE form a triple junction in the Frankfurt/Main area. The Hessian graben displays little neotectonic activity (De Crook, 1993). The active seismic zone along the Rhine River with the URG, the Middle Rhine Area, and the LRE, extending to the Belgian earthquake zone, is the most important earthquake zone of middle Europe north of the Alps. The NRA, which includes the Lower Rhine embayment (Figure 1) and the Roer Valley graben, displays low to moderate seismicity, typical for an intraplate earthquake zone. In the LRE, …