Almost one third of the population of Ecuador is concentrated in two cities(Guayaquil and Quito), which unfortunately are located within regions of moderate to high seismic hazard. In the last century, several strong earthquakes have cause more than 10,000 fatalities, and an economic loss of approximately 2 billion USD. In particular, the earthquake sequence of March 1947 involved three events of magnitude above Mw 6.0 located in the Northern part of the country, and macroseismic intensities of IX were registered.