CURRENT STABILITY MODELLING OF AN INCIPIENT SAN ANDRES GIANT LANDSLIDE ON EL HIERRO ISLAND, CANARIES, SPAIN - FIRST ATTEMPT USING LIMITED INPUT DATA

This paper presents first results from stability modelling of a deep-seated San Andres Landslide located on the El Hierro Island, Canaries. It combines information from own surficial field surveys, geotechnical testing, literature and analogies from other parts of the island and Canary Islands in general. Despite using limited data a slope profile for modelling has been defined and several models have been calculated. These include variations in the rock properties, influence of seismic loading and differences in sea level. This first attempt shows that San Andres Landslide is currently stable however; it might be reactivated as a result of an earthquake with minimum VII intensity. Even in seismically calm periods a creep might be induced by the unconsolidated sea sediments located at the toe of the landslide. However, more detailed information about the internal structure of the landslide and rock properties is needed for thorough conclusions.