A database of damaging small-to-medium magnitude earthquakes

Abstract

Interest in small-to-medium magnitude earthquakes and their potential consequences has increased significantly in recent years, mostly due to the occurrence of some unusually damaging small events, the development of seismic risk assessment methodologies for existing building stock, and the recognition of the potential risk of induced seismicity. As part of a clear ongoing effort of the earthquake engineering community to develop knowledge on the risk posed by smaller events, aglobal database of earthquakes withmomentmagnitudes in the range from 4.0 to 5.5 for which damage and/or casualties have been reportedhas been compiledand is made publicly available. Thetwo main purposeswereto facilitate studies onthe potential for earthquakes in thismagnitude range to cause material damage and to carry out a statistical study to characterise the frequency with which earthquakes of this size cause damage and/or casualties(published separately). The present paper describes the data sources and processfollowedfor the compilation of the database, whileproviding critical discussions on the challenges encounteredand decisions made, which are of relevance for itsinterpretation and use.The geographic, temporal and magnitude distributions of the 1,958 earthquakesthat make up the databaseare presented alongside thegeneral statistics on damage and casualties, noting that these stem from a variety of sources of differing reliability.Despite its inherent limitations, we believe it is an important contributionto the understanding of the extent of the consequences that may arise from earthquakes in the magnitude range of study.