For the pre-modern monitoring period, before 1975, the Earthquake Catalogue of Switzerland (ECOS, 2009) lists a total of 40 earthquakes in a distance range of 10 km of the Malménergie Naturelle project site. Eleven of these earthquakes had intensities of V (indicating slight damage) or larger. The strongest events reached magnitudes of 5.2Mw (1846, Mathod-Yverdon-les-Bains), 4.7Mw (1898, St. Croix-Yverdon) and 5.0Mw (1929, Bioley-Magnoux). Please note that the locations of these events were estimated from historical sources and not derived from instrumental seismic recordings. Therefore, their location uncertainties may reach several 10s of kilometers.
Between January 1975 (start of modern national seismic network) and December 2021, 22 earthquakes have been detected by the SED in the same region. Their magnitudes range from 0.9ML to 2.7ML, with eight earthquakes reaching magnitudes above 2.0ML. Vertically, the earthquakes are distributed over the entire earth’s crust. None of these earthquakes are located within a 2 km distance of the Malménergie Naturelle project site. The estimated completeness magnitude of the earthquake catalog for the modern monitoring period before installing the new network is 1.6ML in the area of interest, and smaller earthquakes may have been missed.