The underwater volcano of El Hierro : a natural laboratory.

Two years after the eruption of the submarine volcano south of the island of El Hierro, in the Canary Islands , it remains under surveillance.

Traces of submarine eruption in Las Calmas Sea south of La Restingua / El Hierro on 16.11.2011 - Photo Guardia Civil / INVOLCAN

Under the Vulcano 2013 project, a new bathymetry was performed , as well as studies on the evolution of the physico -chemical properties in the area of ​​primary and secondary cones of the underwater volcano Las Calmas.

 New 3D bathymetry of the underwater volcano of El Hierro - doc . Projecto Vulcano / IEO 2013


     Study area in 2013 south of El Hierro, in the sea of ​​Las Calmas - doc . Projecto Vulcano / IEO

 A description by Francisco José López Rodríguez / IEO :
" Records show a steep deep zone , characterized by an abundance of bulk materials , presumably detached from upper zones  (abundant sand, gravel and volcanic bombs .) The intermediate zone is steeper and consolidated, covered by crevices, shelter for the decapod. The top is characterized by its particular coloring : the black lava is stained by orange- brown areas, and other whitish or yellowish (emission of sulfur and iron salts ) . "

The research vessel Alvariño Angeles , from the IEO - Spanish Oceanographic Institute - recently placed a probe to analysis of the water column underlying.

                       Preparing of the water control buoy (linked to satellites) by IEO teams

 
Echogram of the EK60 probe above a secondary cone, which reveals the presence of a plume of emission from the basement - doc . Projecto Vulcano / IEO

Although emissions of lava has stopped , the volcano still strongly degassed. CO₂ is emitted by four of its cones , which generate anomalies in the environment. Measurements of temperature, salinity, pH, total inorganic carbon, dissolved oxygen, or concentration of iron in the reduced state were performed.

In comparison with non- affected areas ( reference stations ), and taking into account the changes in the parameters of temperature and pH associated with predicted climate change ( increase in average ocean temperature of 0.6°C and pH decrease of 0.1 units , because of the excess CO₂ in the atmosphere and its absorption by the ocean ) , the area of ​​underwater volcano has an average elevation of 1.5°C and abnormal pH of 0.2 units ... these features will make the underwater volcano of El Hierro a natural laboratory to study some of the main processes related to global warming and ocean acidification .

Sources :

- Campana Vulcano 1013 : las emisiones de material del volcan submarino - link.

- IEO -El volcan submarino de El Hierro continua emitiendo CO₂ por cuatro de sus nueve conos - link
- NPG - The submarine volcano eruption at the island of El Hierro: physical-chemical perturbation and biological response - by E. Fraile-Nuez, M. González-Dávila, J. M. Santana-Casiano, J. Arístegui, I. J. Alonso-González, S. Hernández-León