[S04-3] Historical and macroseismic studies of earthquakes III

[S04-3-01] A STRUCTURED AND HIERARCHICAL DATABASE OF MEXICAN HISTORICAL EARTHQUAKES: 1469 TO 1912

^○Gerardo Suarez¹, Carlos Chico², Daniel Ruiz² (1.INSTITUTO DE GEOFISICA, UNAM, 2.FACULTAD DE INGENIERIA, UNAM)

invited

A structured and hierarchical database of historical earthquakes in Mexico during the last 450 years was designed and developed. The macroseismic data were located using the official Mexican almanac and to all identified locations a value of intensity on the Modified Mercalli Intensity (MMI) value was assigned. In total, 328 earthquakes were identified from 1469 to 1912. The earthquakes were classified according to their tectonic origin. The database may be queried by date, date range, seismic region or locality. Specific queries may also be made for buildings reportedly damage or associated phenomena to earthquake. The full verbatim macroseismic information may also be accessed from the database so the user can make their decision regarding the interpretation. When sufficient data were available, the epicenter and magnitude of the earthquakes was estimated following the inversion method of macroseismic data points proposed by Bakun and Wentworth (1997). For this purpose, attenuation curves of attenuation versus moment magnitude were constructed for three general categories of earthquakes in Mexico: subduction zone, in-slab earthquakes in the subducted Cocos plate and crustal earthquakes. As a first example, the resulting catalog has been used to study the seismicity of the Trans Mexican Volcanic Belt (TMVB). This region is where the largest concentration of the population of Mexico lives. As a result, several crustal earthquakes on the TMVB were identified, which were previously unknown. The database is open and available to any interested user at http://sismoshistoricos.org/.