In Marwth Vallis, OMEGA maps the water-rich minerals

In this HRSC 3D perspective view of the Marwth Vallis area (shades of grey), OMEGA has mapped the water-rich minerals (blue). No hydrated minerals or sediments have been detected, either in the channel or in its opening. However, the outflow was so violent as to erode and expose ancient hydrated clay-rich minerals, tracing an early era when water was present.