Some of the valleys in the Elysium quadrangle seem to start from grabens.
 Granicus Vallis and Tinjar Vallis begin at a graben that lies just to the west of Elysium Mons.
 Certain observations suggest that they may have been the location of lahars (mudflows).
 The graben may have formed because of volcanic dikes.
 Heat from the dikes would have melted a great deal of ice.
 Two valley systems, the Hephaestus Fossae and Hebrus Valles, have sections that join and branch at high angles.

The Athabasca Valles are perhaps the youngest outflow channel system on Mars.
They lie 620 miles southeast of the large volcano Elysium Mons.
Athabasca was formed by water that burst out of the Cerberus Fossae, a set of cracks or fissures in the ground.
The Cerberus Fossae most likely were formed from the stress on the crust caused by the weight of both Elysium Mons and the Tharsis volcanoes.
Current evidence suggests that Cerberus floods probably erupted in several stages.
 Near the start of these channels (at one of the Cerberus Fossae), the system is called the Athabasca Valles; to the south and east it is called Marte Vallis.
Flow rates in Marte Vallis have been estimated at around 100 times that of the Mississippi River.
Eventually, the system just seems to fade out in the plains of Amazonis Planitia.
Some of the valleys in the Elysium quadrangle seem to start from grabens.  Granicus Vallis and Tinjar Vallis begin at a graben that lies just to the west of Elysium Mons.  Certain observations suggest that they may have been the location of lahars (mudflows).  The graben may have formed because of volcanic dikes.  Heat from the dikes would have melted a great deal of ice.  Two valley systems, the Hephaestus Fossae and Hebrus Valles, have sections that join and branch at high angles.
The Athabasca Valles are perhaps the youngest outflow channel system on Mars. They lie 620 miles southeast of the large volcano Elysium Mons. Athabasca was formed by water that burst out of the Cerberus Fossae, a set of cracks or fissures in the ground. The Cerberus Fossae most likely were formed from the stress on the crust caused by the weight of both Elysium Mons and the Tharsis volcanoes. Current evidence suggests that Cerberus floods probably erupted in several stages.  Near the start of these channels (at one of the Cerberus Fossae), the system is called the Athabasca Valles; to the south and east it is called Marte Vallis. Flow rates in Marte Vallis have been estimated at around 100 times that of the Mississippi River. Eventually, the system just seems to fade out in the plains of Amazonis Planitia.
Elysium quadrangle