5 April 2006
This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the margin of a lava flow on a plain northwest of Jovis Tholus, a volcanic construct located in the Tharsis region of Mars. To the north (top) of the lava flow, islands of a material that was once more laterally extensive are present, suggesting that at some time in the past, a great deal of this material was removed by erosion -- perhaps a catastrophic flood of water and debris. The lava flow at the south (bottom) came in later, long after the erosional events occurred.

Location near: 20.9°N, 118.9°W
Image width: ~3 km (~1.9 mi)
Illumination from: lower left
Season: Northern Winter