The 2014–2015 Holuhraun Lava Flow-Field in Iceland as a Planetary Analog for Young Volcanic Terrains in Elysium Planitia, Mars

Understanding volcanic processes is essential for unraveling Mars’ geological history and 23 evolution. The recent volcanism in Elysium Planitia is of special interest because (a) the pristine 24 morphology of these lavas provides insight into emplacement processes that is lost elsewhere, (b) 25 an improved understanding of eruptions in this region may help understand seismic data, which 26 indicate that magma may still reside underneath this region, and (c) properly interpreting the 27 suggestions of interactions between volcanic and aqueous processes in Elysium Planitia may have 28 important astrobiological implications. The 2014–2015 Holuhraun eruption in the Icelandic 29 Highland provides a unique opportunity to study a large-volume fissure-fed eruption with lava– 30 water interaction as a terrestrial analog to the volcanic terrains of Elysium Planitia on Mars. Here, 31 we detail the key similarities between the Holuhraun region and Elysium Planitia, including their 2 32 geological settings and lava morphologies. In particular, both include a variety of “transitional” 33 lava types, detailed investigations of which provide valuable insights into the dynamics and 34 evolution of large fissure-fed eruptions on Earth and Mars. Consequently, Mars analog research in 35 young volcanic terrains in Iceland can provide extremely valuable information to inform the study 36 of martian volcano–tectonic activity and its implications for the planet’s geological evolution, past 37 habitability, and present-day processes.