Basalt-hosted microbial communities in the subsurface of the young volcanic island of Surtsey, Iceland.

The young oceanic island produced by Surtsey volcano in 1963–1967 on the offshore Icelandic volcanic rift zone offers a unique opportunity to study the subsurface biosphere in newly formed oceanic crust and its associated hydrothermal-seawater system. Here we present new insights into the abundance, distribution and diversity of microorganisms in the subsurface of Surtsey 50 years after eruptions terminated. Results of this microbial survey, including basaltic tuff drill cores and associated fluids acquired at successive depths as well as surface fumes, are investigated based on 16S rRNA gene amplicon sequencing.