101 ANNIVERSARY OF BREŽICE EARTHQUAKE

Abstract

Extensive historical and seismological studies, that were made on 101st anniversary of Brežice earthquake, have brought a number of new findings. The earthquake on 29 January 1917 near Brežice occurred at 9:22 local time. The earthquake caused the strongest effects in four localities: Brežice, Krška vas, Šentlenart and Zakot, where the intensity was VIII EMS-98. Original documents on damage (today kept in Archives of Slovenia in Ljubljana) enabled us to have a detailed insight into the situation in the most damaged area, as well as to make a statistics of damage according to the European Macroseismic Scale. Considering the macroseismic data, the epicentre of the earthquake was 1 km SW of Brežice. Its macroseismic magnitude was 5.0. Two people died and several people were injured. Several houndred buildings were damaged. According to the intensity, Brežice earthquake was the strongest earthquake in 20th century with its focus in Slovenia. The Friuli earthquake (6 May 1976) had higher intensities in Slovenia, but its focus was in Italy. The earthquake on 12 April 1998 in Upper Soča Valley had higher magnitude, but did not produce as high intensities as Brežice earthquake. The main outcome of this study is that we used the cadastral plans and land plot records of the land cadastre and combined them with data from the documents on damage in order to visualise the spatial distribution of the damaged buildings. This is the first such visualisation of damage for a Slovenian earthquake.