EARTHQUAKE HAZARD MITIGATION IN CENTRAL AMERICA BY STUDIES OF SEISMIC SOURCE AND GROUND ACCELERATION

摘要

Central America is a region that has been prone to numerous destructive earthquakes, like the 1972 Managua earthquake, the 1976 Guatemala earthquake and the 1986 San Salvador earthquake among others. Thus, observations of complex faulting of Central American earthquakes have inspired us to investigate rupture processes of earthquakes in that region. E.g., the earthquakes, September 02, 1992, Mw=7. 6, Nicaragua, and the October 18, 1992, Mw=7.1, Colombia, events are notable examples. Thus we are studying source processess of major Central American earthquakes that have occurred during the time of the digital worldwide networks. In order to obtain rupture information we use data from both teleseismic as well as local/regional distances. The techniques we use at telsesimic distances include modelling of the source-time function by inversion of body waves as well as using a empiricial Green's function approach. From the obtained source time function of the 1992 Colombia earthquake we find that on one third of the fault the slip is 70% larger than the average.