Three-dimensional view of the west Ceti Mensa

Three-dimensional view of the west Ceti Mensa area looking toward the southeast. These rock layers formed as wind-blown sand that became trapped in shallow, ephemeral lakes. If present, past life on Mars living in these lakes or in water underground may have been incorporated into these layers as the wind-blown sand accumulated. Any such evidence of past life may now be preserved as fossils within the layers.

A new set of high-resolution geologic maps reveal complex geologic processes that suggest a dynamic, wet environment once existed on early Mars, according to the USGS.