An Attempt to Determine the Magnitudes and Epicenters of Significant Historical Earthquakes in the Pannonian Basin

Abstract

This study aims to determine the epicenters and magnitudes of pre-instrumental historical earthquakes in the Pannonian basin based on contemporary sources and the literature that recorded the effects, damage, and accompanying events. A local intensity value for a given place was estimated only if it could be determined based on contemporary data. Using intensity data from different locations, the position of the hypocenter and magnitude of the historic earthquakes were calculated using an empirical equation. The epicenter positions were compared with the spatial distribution of liquefaction phenomena, foreshocks, and aftershocks, for which data were available. Finally, the set of historical Mw≥5.5 events is supplemented with locations of instrumentally measured earthquakes of similar sizes, and the relationship between the location of the resulting seismic events and the main tectonic structures of the Pannonian basin is investigated. Our investigation suggests that the location of the earthquake epicenters is not linked to known major tectonic structures and that the earthquake activity in the Pannonian basin may be higher than previously thought.