Submarine landslide catalogue onshore/offshore harmonization; Spain as a case study

This paper presents a Geographic Information System catalogue of the submarine landslides of the Spanish continental margin and describes the problems associated with harmonizing the catalogue with its onshore homologue. The data model structure is described to explain how to apply the rules and specifications following the Infrastructure for Spatial Information in Europe (INSPIRE). Because of the singularities of the marine environment compared with those of land, integrating the submarine landslide catalogues into INSPIRE specifications requires the following procedures: (1) simplification of the list of values of state of activity into three categories: active, dormant and relict; and (2) inclusion of debris avalanches and turbidites as new typologies of landslides. This paper discusses the problems associated with harmonizing different data types and units from different sources, such as the thickness (metres and seismic two travel time) or the age of the event, and a numeric code for the geological timescale is proposed to harmonize these data. We establish whether an item is required based on the reliability of the landslide event, which is categorized by three levels (high-middle-low) depending on the precision of the data source, methodology used and quality of the publication where the data are obtained.