A new eruptive era/cycle on the Reykjanes Peninsula, SW Iceland; Understanding magma sources, magma supply, and societal consequences

The Reykjanes peninsula (RP) features seven volcanic lineaments that were active during three multi-centennial eruption periods over the last 4000-years, each of which was separated by a repose interval of ~800-years.

After 781-years of dormancy, the 2021 Geldingadalir eruption of the Fagradalsfjall volcanic lineament marks the onset of a new eruption period on the RP.

This was followed by two further eruptions at Fagradalsfjall and then by four eruptions at Sundhnúkur (Svartsengi volcanic lineament), totalling seven eruptions in the last three years.

This pattern of activity is likely to continue for decades and poses a considerable risk to population centres and critical infrastructure in this most densely populated region of Iceland.

To fully understand the nature of this prolific magma supply system and associated eruptions, we propose to produce time-resolved geochemical and isotope data from rocks and minerals to fully characterise temporal changes in magma supply, the growth and origin of magma storage reservoirs, and the build-up of the newly emerging lava fields on the RP.

By integrating field mapping, mineralogical, geochemical, and micro-beam isotopic data with seismic and remote sensing data, we will achieve an unprecedented level of detail that will allow us to model magmatic processes and assess the geological consequences of this latest eruptive period and the threats it poses to society.