Hazards in El Salvador from earthquake-induced landslides

This report addresses the landslide situation in El Salvador, but because of limitations in available literature, is restricted to earthquake-induced landslides. The importance of earthquake-induced landslides to El Salvador was made clear by the 1986 San Salvador earthquake, which triggered several hundred landslides that killed at least 200 people. Nine other cases of earthquake-induced landslides are documented in El Salvador in the last approximately 130 years. Earthquakes that cause landslides in El Salvador include both subduction-zone events and upper-crustal events. Earthquake-caused landslides are commonly limited to a narrow zone coincident with the main volcanic chain, coastal mountains, and interior valley physiographic provinces. Widespread throughout this area is poorly consolidated volcanic tuff, a major contributing factor in the landslides caused by the 1986 San Salvador earthquake, and probably is a major contributor to the overall abundance of landslides in the region.