1763 Komárom earthquake

Earthquake affecting Hungary 1763 Komárom earthquake yes 1763 06 28 05:28 Hungary 6.2 to 6.5 w y 15.0 km 47.73 N 18.15 E type:event_region:IN-HP inline,title Kingdom of Hungary IX 83 The 1763 Komárom earthquake occurred on 28 June between 5 and 6 in the morning, in or near the town of Komárom in Komárom County in the Kingdom of Hungary, close to the current border with Slovakia. The earthquake has been estimated at 6.2 to 6.5 on the moment magnitude scale (w). Background The Komárom earthquake was an intraplate earthquake in the Pannonian Basin associated with the Rába-Hurbanovo tectonic zone, which separates the Internal Western Carpathians and the Central Western Carpathians crustal blocks. This zone was formed during the Cretaceous as a fold and thrust belt, which was later reactivated as a backthrust or a strike-slip zone during the Paleogene to Early Miocene. It was further reactivated as a normal fault during the development of the Danube basin as part of the overall Pannonian Basin. Earthquakes in the region are caused by deformation resulting from the movement of the Adriatic plate relative to the Eurasian plate. Earthquakes were observed in the Komárom area in 1754, 1757 and 1759. By 1758, the perceived earthquake risk was high enough that a church ceremony was held in an attempt to ward off a major earthquake. Large parts of Hungary are covered by a layer of Holocene fluvial sediments, with an elevated ground water level. This makes many areas vulnerable to soil liquefaction during earthquake shaking. Earthquake The magnitude of the earthquake has been estimated from the intensities based on contemporary reports, ranging from 5.7 w (SHEEC) catalogue,AHEAD European Archive of Historical EArthquake Data 28 June 1763, 04:30 Komárno https://www.emidius.eu/AHEAD/event/17630628_0430_000 26 July 2025 to 6.5 w. The focal depth has also been estimated from intensity distributions, varying from 7.6 km to 15 km. The 1763 earthquake accounts for about 80% of all the seismic moment released in the Komárom area since 1599. Due to the lack of seismologic instruments in 1763, the mechanism of and depth of the earthquake are not known with any certainty, though most earthquakes in the region occur in the upper 20 km of crust. It was the largest event known from the Pannonian Basin in the last thousand years. There was a strong foreshock about 15 minutes before the mainshock. Many aftershocks were recorded after the event. Recent probabilistic analyses have applied structural fragility functions to the 1763 Komárom earthquake in order to refine its magnitude estimate. Morais and colleagues (2017) developed analytical fragility functions by modelling a typical one‑storey commoners' house archetype—representative of the adobe masonry dwellings in Komárom—using dynamic structural analysis in OpenSees (a software framework for earthquake simulation) and 30 site‑specific ground‑motion records for the region. Combining these functions with contemporary damage reports (which record that some 91 % of the town's 1169 houses were affected, including 279 total collapses and 353 partial collapses) and central European attenuation relations, the study obtained preliminary magnitude estimates of Mw 6.20–6.97 for an epicentral distance of 10 km and Mw 6.44–7.08 for 12 km. When uncertainties in damage‑state counts, material properties and choice of attenuation model were fully incorporated, the posterior mean magnitude was calculated at about 6.4 with a standard deviation of about 0.6. The maximum estimated intensity is IX on the European Macroseismic Scale (EMS-98) for Komárom. An intensity of VIII has been estimated for Madar and Perbete, VII–VIII for Komáromszentpéter and Hidaskürt and VII for Izsa, Győr and Érsekújvár. Based on contemporary reports soil liquefaction effects were observed over an area of about 400 km2. Impact right|290px|thumb|Detail of contemporary painting of damage to Komárom Damage in Komárom was extensive, with 279 houses completely collapsing out of the 1169 houses in the city. A further 353 houses suffered partial collapse, 213 required major repairs and 219 needed only minor repairs. Multistory buildings were particularly badly affected. The houses in the city were described as strongly-built before the earthquake due to the possibility of coming under siege. Contemporary reports note that seven churches collapsed and that the newly constructed Jesuit church and college were heavily damaged, including the collapse of two towers onto a neighboring school, which killed several people. Győr suffered widespread damage, with no buildings in the central part of the city escaping some effects of the earthquake. As with Komárom, the larger the building, the greater the damage. Both the Episcopal Palace and the Carmellite church were severely damaged. The earthquake killed 63 people in Komárom and 102 people were wounded. 85 deaths have been mentioned in another source and estimates of the total death toll reach 200–300. Four deaths were also reported from Gjőr. See also 1956 Budapest earthquake Geology of the Western Carpathians List of historical earthquakes References 30em Isoseismal map and tectonical position of the Komárom earthquake of 1763 Péter Varga Gy. Szeidovitz Rudolf Gutdeutsch Acta Geodaetica et Geophysica Hungarica March 2001 36 1 97–108 10.1556/AGeod.36.2001.1.8 140629684 https://www.researchgate.net/publication/250007875 2016-01-06 Varga P. Győri E. Timár G. 2021 The Most Devastating Earthquake in the Pannonian Basin: 28 June 1763 Komárom Seismological Research Letters 92 2A 1168–1180 Strain Rates, Seismic Activity And Its Temporal Variations Within The Pannonian Basin 2004 Acta Geodaetica et Geophysica Hungarica Péter Varga Zoltan Bus Márta Kiszely https://www.researchgate.net/publication/267253334 39 2-3 327-337 Geodetic and Geophysical Research Institute, Seismological Observatory 2016-01-06 Abhandlungen der Geologischen Bundesanstalt Historical Earthquakes in Central Europe Wien August 1992 48 33–50 http://www.zobodat.at/stable/pdf/AbhGeolBA_48_0033-0050.pdf Ute Eisinger Rudolf Gutdeutsch Christa Hammerl 0378-0864 3-900312-83-4 Morais E. Vigh L G. Krähling J. Preliminary estimation of the probable magnitude of Komárom 1763 earthquake using fragility functions 16th World Conference on Earthquake Engineering (16WCEE) Santiago, Chile 9–13 January 2017 No. 4454 https://wcee.nicee.org/wcee/article/4454.pdf National Geophysical Data Center / World Data Service (NGDC/WDS): Significant Earthquake Database. 1972 NOAA National Centers for Environmental Information 10.7289/V5TD9V7K https://www.ngdc.noaa.gov/hazel/view/hazards/earthquake/event-more-info/1372 2022-04-15 National Geophysical Data Center Plašienka D. 2018 Continuity and Episodicity in the Early Alpine Tectonic Evolution of the Western Carpathians: How Large-Scale Processes Are Expressed by the Orogenic Architecture and Rock Record Data Tectonics 37 7 2029–2079 10.1029/2017TC004779 free Zsíros T. 2008 Report on the earthquake of June 28, 1763. – Komárom https://www.emidius.eu/AHEAD/event/17630628_0430_000 Győri E. Tóth L. Mónus P. 2015 Secondary effects generated by earthquakes: liquefaction occurrences in and around Hungary Acta Geodaetica et Geophysica 50 79–95 10.1007/s40328-014-0079-z Category:1760s earthquakes Category:1763 disasters Category:18th century in Hungary Category:1763 in the Habsburg monarchy Category:Earthquakes in Europe Category:Natural disasters in Hungary Category:Geology of Hungary