Evidence for geologically recent explosive volcanism in Elysium Planitia, Mars

Volcanic activity on Mars peaked during the Noachian and Hesperian periods but has continued since then in isolated locales. Elysium Planitia hosts numerous young, fissure-fed flood lavas with ages ranging from approximately 500 to 2.5 million years (Ma). We present evidence for what may be youngest volcanic deposit yet documented Mars: a low albedo, high thermal inertia, high-calcium pyroxene-rich distributed symmetrically around segment of Cerberus Fossae fissure system Planitia. This is similar features interpreted as pyroclastic deposits Moon Mercury. However, unlike previously lava flows Planitia, this feature morphologically consistent deposit, mantling surrounding thickness order tens cm over most volume 1.1-2.8E7 cubic meters. Thickness estimates are tephra fall Earth. Stratigraphic relationships indicate relative age younger than plains Zunil impact crater (~0.1-1 Ma), counting suggesting an absolute model 53 210 ka. young implies that if origin region not extinct still volcanically active today. interpretation identification seismicity by Interior Exploration using Seismic Investigations, Geodesy, Heat Transport (InSight) lander, additional implications astrobiology source transient atmospheric methane.