Mars: Water-Rich Terrain (IMAGE) Johns Hopkins University Caption This three-dimensional image of a trough in the Nili Fossae region of Mars shows a type of minerals called phyllosilicates (in magenta and blue hues) concentrated on the slopes of mesas and along canyon walls. The abundance of phyllosilicates shows that water played a sizable role in changing the minerals of a variety of terrains in the planet's early history. Credit NASA/JPL/JHUAPL/University of Arizona/Brown University. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.