File:260188-JezeroCraterRegion-NiliFossae-Trough.jpg
http://www.nasa.gov/mission_pages/MRO/multimedia/trough-20080716.html
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.