FROM "ISAURIA" TO LYDIA: REVISING THE EPICENTER OF THE 1213 PHILADELPHIA EARTHQUAKE

This note shows that one may relocate the epicenter of the 1213 earthquake, as based on one direct source edited by R. Roricht in Regesta Regni Hierosolymitani (1893). The source in question was acritically accepted in two Catalogues of historical seismology (Guidoboni & Comastri 2005 and Ambraseys 2009) and by an important article by Halfter (2009). It proved necessary to return to the original manuscript and use palaeography to clarify the place name on which previous interpretations were based. The destructive 1213 earthquake was first placed at Philadelphia in the region of "Isauria" (present-day southeast Turkey). Thanks to palaeographic analysis of that place name, the event is here interpreted as involving the area of Lydian Philadelphia, in western Turkey, an area well-known for earthquakes since ancient times. The note illustrates the process and importance of proper toponymy in historical seismology when it comes to pinpointing epicenters.