Rootless cones on Mars indicating the presence of shallow equatorial ground ice in recent times

High resolution Mars Orbiter Camera (MOC) images have revealed the existenc e of clusters of small cones in the Cerberus plains, Marte Valles, and Amaz onis Planitia, Mars. These cones are similar in both morphology and planar dimensions to the larger of Icelandic rootless cones, which form due to exp losive interactions between surficial lavas and near-surface groundwater. I mpact crater size-frequency relationships indicate that surfaces upon which the cones sit are no older than 10 Ma. If martian cones form in the same m anner as terrestrial rootless cones, then equatorial ground ice or ground w ater must have been present near the surface in geologically recent times.