Two light earthquakes with equal local magnitudes of ML 4.3 occurred in 2011 in the northern Rhine area, Germany. They were recorded with 40 stations, including 20 strong‐motion free‐field stations. Some of these, particularly those in the city of Cologne, have the same epicentral distance from both earthquake sources. These data are ideal for using the ratios of ground‐motion parameters (peak ground acceleration, peak response amplitude, and corresponding frequencies) from the two earthquakes measured with identical stations and thus provide site‐effect independent distance relations. The two source locations in the Rhenish shield and in the Lower Rhine embayment show different decays of the ground‐motion amplitudes with respect to distance. The records from four stations in Cologne Cathedral illustrate the differences in structural response despite the similar size earthquakes.

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