Elysium Quadrangle - Vallis in The Elysium Quadrangle

Vallis in The Elysium Quadrangle

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 valleys, Hephaestus Fossae and Hebrus Valles, have sections that join and branch at high angles.

Perhaps the youngest outflow channel on Mars is Athabasca Valles. It lies 620 miles southeast of the large volcano Elysium Mons. Athabasca was formed by water that burst out of Cerberus Fossae, a set of cracks or fissures in the ground. Cerberus Fossae most likely was formed from the stress on the crust caused by the weight of both Elysium Mons and Tharsis volcanoes. Current evidence suggests that Cerberus floods probably erupted in several stages. Near the start of these channels (Cerberus Fossae), the system is called 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.

• Athabasca Valles Streamlined Form, as seen by HiRISE. Click on image to see layers.

• Stura Vallis, as seen by HiRISE. Scale bar is 500 meters long.

• Lethe Vallis, as seen by HiRISE. Flow was from southwest to northeast. Wider part of Lethe Vallis had less erosive power, so mesas are left behind from pre-existing material. Scale bar is 500 meters long.

• Patapsco Vallis, as seen by HiRISE. Scale bar is 1000 meters long.

• Rahway Valles, as seen by HiRISE. Scale bar is 500 meters long.

• Ituxi Vallis, as seen by THEMIS. Ituxi Vallis is a lava channel that lies east of Elysium Mons.