Spatial probability distribution of future volcanic eruptions at El Hierro Island (Canary Islands, Spain)

• Susceptibility is based on the spatial statistical analysis of past structural data.
• Volcanic structures are converted in weighted PDFs and combined in a Poisson Process.
• A back analysis procedure is used to assign the best weight to each of the PDFs.
• The major probabilities of future eruptions follow the distal parts of S and W rifts.
• Our method is exportable to other volcanoes or to other kinds of hazardous phenomena.

The 2011 submarine eruption that took place in the proximity of El Hierro Island (Canary Islands, Spain) has raised the need to identify the most likely future emission zones even on volcanoes characterized by low frequency activity. Here, we propose a probabilistic method to build the susceptibility map of El Hierro, i.e. the spatial distribution of vent opening for future eruptions, based on the probabilistic analysis of volcano-structural data of the Island collected through new fieldwork measurements, bathymetric information, as well as analysis of geological maps, orthophotos and aerial photographs. These data have been divided into different datasets and converted into separate and weighted probability density functions, which were included in a non-homogeneous Poisson process to produce the volcanic susceptibility map. The most likely area to host new eruptions in El Hierro is in the south-western part of the West rift. High probability locations are also found in the Northeast and South rifts, and along the submarine parts of the rifts. This map represents the first effort to deal with the volcanic hazard at El Hierro and can be a support tool for decision makers in land planning, emergency measures and civil defense actions.